Aims. The ongoing COVID-19 pandemic has disrupted and delayed medical and surgical examinations where attendance is required in person. Our article aims to outline the validity of online assessment, the range of benefits to both candidate and assessor, and the challenges to its implementation. In addition, we propose pragmatic suggestions for its introduction into medical assessment. Methods. We reviewed the literature concerning the present status of online medical and surgical assessment to establish the perceived benefits, limitations, and potential problems with this method of assessment. Results. Global experience with online, remote virtual examination has been largely successful with many benefits conferred to the trainee, and both an economic and logistical advantage conferred to the assessor or organization. Advances in online examination software and remote proctoring are overcoming practical caveats including candidate authentication, cheating prevention, cybersecurity, and IT failure. Conclusion. Virtual assessment provides benefits to both trainee and assessor in medical and surgical examinations and may also result in cost savings. Virtual assessment is likely to be increasingly used in the post-COVID world and we present recommendations for the continued adoption of virtual examination. It is, however, currently unable to completely replace clinical assessment of trainees. Cite this article: Bone Jt Open 2021;2(2):111–118

Aims. The purpose of our study was to determine which groups of orthopaedic providers favour virtual care, and analyze overall orthopaedic provider perceptions of virtual care. We hypothesize that providers with less clinical experience will favour virtual care, and that orthopaedic providers overall will show increased preference for virtual care during the COVID-19 pandemic and decreased preference during non-pandemic circumstances. Methods. An orthopaedic research consortium at an academic medical system developed a survey examining provider perspectives regarding orthopaedic virtual care. Survey items were scored on a 1 to 5 Likert scale (1 = “strongly disagree”, 5 = “strongly agree”) and compared using nonparametric Mann-Whitney U test. Results. Providers with less experience were more likely to recommend virtual care for follow-up visits (3.61 on the Likert scale (SD 0.95) vs 2.90 (SD 1.23); p = 0.006) and feel that virtual care was essential to patient wellbeing (3.98 (SD 0.95) vs 3.00 (SD 1.16); p < 0.001) during the pandemic. Less experienced providers also viewed virtual visits as providing a similar level of care as in-person visits (2.41 (SD 1.02) vs 1.76 (SD 0.87); p = 0.006) and more time-efficient than in-person visits (3.07 (SD 1.19) vs 2.34 (SD 1.14); p = 0.012) in non-pandemic circumstances. During the pandemic, most providers viewed virtual care as effective in providing essential care (83.6%, n = 51) and wanted to schedule patients for virtual care follow-up (82.2%, n = 50); only 10.9% (n = 8) of providers preferred virtual visits in non-pandemic circumstances. Conclusion. Orthopaedic providers with less clinical experience seem to favourably view virtual care both during the pandemic and under non-pandemic circumstances. Providers in general appear to view virtual care positively during the pandemic but are less accommodating towards it in non-pandemic circumstances. Cite this article: Bone Jt Open 2021;2(6):405–410

The use of journal clubs and, more recently, case-based discussions in order to stimulate debate among orthopaedic surgeons lies at the heart of orthopaedic training and education. A virtual learning environment can be used as a platform to host virtual journal clubs and case-based discussions. This has many advantages in the current climate of constrained time and diminishing trainee and consultant participation in such activities. The virtual environment model opens up participation and improves access to journal clubs and case-based discussions, provides reusable educational content, establishes an electronic record of participation for individuals, makes use of multimedia material (including clinical imaging and photographs) for discussion, and finally, allows participants to link case-based discussions with relevant papers in the journal club. The Leicester experience highlights the many advantages and some of the potential difficulties in setting up such a virtual system and provides useful guidance for those considering such a system in their own training programme. As a result of the virtual learning environment, trainee participation has increased and there is a trend for increased consultant input in the virtual journal club and case-based discussions. It is likely that the use of virtual environments will expand to encompass newer technological approaches to personal learning and professional development

Aims. The aim of this study was to describe the introduction of a virtual pathway for the management of patients with a suspected fracture of the scaphoid, and to report patient-reported outcome measures (PROMs) and satisfaction following treatment using this service. Methods. All adult patients who presented with a clinically suspected scaphoid fracture that was not visible on radiographs at the time of presentation during a one-year period were eligible for inclusion in the pathway. Demographic details, findings on examination, and routine four-view radiographs at the time of presentation were collected. All radiographs were reviewed virtually by a single consultant hand surgeon, with patient-initiated follow-up on request. PROMs were assessed at a minimum of one year after presentation and included the abbreviated version of the Disabilities of the Arm, Shoulder and Hand Score (QuickDASH), the EuroQol five-dimension five-level health questionnaire (EQ-5D-5L), the Net Promoter Score (NPS), and return to work. Results. A total of 221 patients were referred to the virtual pathway. Their mean age was 41 years (range 16 to 87) and there were 99 male patients (45%). A total of 189 patients (86%) were discharged with advice and 19 (9%) were recalled for clinical review: seven with an undisplaced scaphoid fracture, six with another fracture of the hand or wrist, two with a scapholunate ligament injury, and four in whom no abnormality was detected. A total of 13 patients (6%) initiated follow-up with the hand service: no fracture or ligament injury was identified in this group. PROMs were available for 179 patients (81%) at a mean follow-up of 19 months (range 13 to 33). The median QuickDASH score was 2.3 (interquartile range (IQR) 0 to 15.9), the median EQ-5D-5L was 0.85 (IQR 0.73 to 1.00), the NPS was 76, and 173 patients (97%) were satisfied with their treatment. There were no documented cases of symptomatic nonunion one year following injury. Conclusion. We describe the introduction of a virtual pathway for the management of patients with a suspected scaphoid fracture. We found high levels of patient satisfaction, excellent PROMs, and no detrimental effects in the vast majority of cases. Cite this article: Bone Joint J 2022;104-B(6):709–714

Surgical trainees are finding it increasingly more challenging to meet operative requirements and coupled with the effects of COVID-19, we face a future of insufficiently trained surgeons. As a result, virtual reality (VR) simulator training has become more prevalent and whilst more readily accepted in certain arthroscopic fields, its use in hip arthroscopy (HA) remains novel. This project aimed to validate VR high-fidelity HA simulation and assess its functional use in arthroscopic training. Seventy-two participants were recruited to perform two basic arthroscopic tasks on a VR HA simulator, testing hip anatomy, scope manipulation and triangulation skills. They were stratified into novice (39) and experienced (33) groups based on previous arthroscopy experience. Metric parameters recorded from the simulator were used to assess construct validity. Face validity was evaluated using a Likert-style questionnaire. All recordings were reviewed by 2 HA experts for blinded ASSET score assessment. Experienced participants were significantly faster in completing both tasks compared with novice participants (p<0.001). Experienced participants damaged the acetabular and femoral cartilage significantly less than novice participants (p=0.011) and were found to have significantly reduced path length of both camera and instrument across both tasks (p=0.001, p=0.007), demonstrating significantly greater movement economy. Total ASSET scores were significantly greater in experienced participants compared to novice participants (p=0.041) with excellent correlation between task time, cartilage damage, camera and instrument path length and corresponding ASSET score constituents. 62.5% of experienced participants reported a high degree of realism in all facets of external, technical and haptic experience with 94.4% advising further practice would improve their arthroscopic skills. There was a relative improvement of 43% in skill amongst all participants between task 1 and 2 (p<0.001). This is the largest study to date validating the use of simulation in HA training. These results confirm significant construct and face validity, excellent agreement between objective measures and ASSET scores, significant improvement in skill with continued use and recommend VR simulation to be a valuable asset in HA training for all grades

Virtual physiotherapy has been provided to hundreds of patients at the Holland Centre during the COVID pandemic. As we plan for virtual care to be one part of our care delivery we want to evaluate it and ensure the care delivery is safe and effective. The objectives of this project was two-fold: 1) to examine the outcome of virtual physiotherapy and/ or a hybrid of virtual and in-person care in patients who received post-operative treatment following total knee replacement at the Holland Centre, 2) to explore the challenges of virtual care participation in the joint replacement population. Patients who received either virtual care or a combination of in-person and virtual care (hybrid model) based on the patients’ needs were included. Patient-related outcomes were the Patient Specific Functional Scale (PSFS) and pain scale. Flexion and extension range of motion were measured before and after treatment. A modified Primary Care Patient Experience Virtual Care Survey was used to examine barriers for virtual care. Sixty patients, mean age 68(8), ranging between 45-83 years, 34(57%) females, who received either virtual care or a combination of in-person and virtual care based on the patients’ needs were included. Patients showed improvement in the PSFS and pain scores (p<0.0001). Flexion (p<0.0001) and extension (p=0.02) improved at a statistically significant level. A separate sample (N=54) (age range 50-85 years) completed the patient experience survey. A well-designed post-operative virtual physiotherapy program, initially implemented to maintain continuity of care during the pandemic, continues to be an important part of our model of care as we normalize our activities. Clear understanding of barriers to virtual care and mitigation strategies will help us create virtual care standards, meet our patient needs, optimize our care delivery and potentially increase the use of virtual rehab in the future

The response to the COVID-19 pandemic has raised the profile and level of interest in the use, acceptability, safety, and effectiveness of virtual outpatient consultations and telemedicine. These models of care are not new but a number of challenges have so far hindered widespread take-up and endorsement of these ways of working. With the response to the COVID-19 pandemic, remote and virtual working and consultation have become the default. This paper explores our experience of and learning from virtual and remote consultation and questions how this experience can be retained and developed for the future. Cite this article: Bone Jt Open 2021;2(5):301–304

The Severity Scoring System (SSS) is a guide to interpreting findings across clinical, functional, and radiological findings, used by qualified, specially trained physiotherapists in the advanced practice role in order to provide consistency in determining the severity of the patient's condition and need for surgical consultation. The system has been utilized for over 14 years as a part of standardized assessment and management care and was incorporated into virtual care in 2020 following the pandemic restrictions. The present study examined the validity of the modified SSS in virtual care. Patients who were referred to the Rapid Access Clinic (RAC), were contacted via phone by two experienced advanced practice practitioners (APPs) from May to July 2020, when in-person care was halted due to the pandemic. The virtual interview included taking history, completing self-reported measures for pain and functional ability and reviewing the radiological reports. A total of 63 patients were interviewed (mean age 68, SD=9), 34 (54%) females. Of 63 patients, 33 (52%) were considered a candidate for total knee arthroplasty (TKA). Men and women were comparable in age, P4 and LEFS scores. The TKA candidates had a significantly higher SSS (p<0.0001) and pain scores (p=0.024). The variability of the total SSS score explained by the functional, clinical and radiological components of the tool were 55%, 48% and 4% respectively, highlighting the more important role of patient's clinical history and disability in the total SSS. The virtual SSS is a valid tool in directing patients for surgical management when used by highly trained advanced practice physiotherapists. A large component of the SSS is based on clinical data and patient disability and the APP's skillset rather than severity of pathology found on imaging

This study describes the introduction of a virtual pathway for the management of suspected scaphoid fractures and reports patient-reported outcome measures (PROMs) and satisfaction following treatment with this service. All adult patients that presented with a clinically suspected scaphoid fracture that was not visible on presentation radiographs over a one-year period were eligible for inclusion in the pathway. Demographics, examination findings, clinical scaphoid score (CSS) and standard four view radiographs were collected at presentation. All radiographs were reviewed virtually by a single consultant hand surgeon, with patient-initiated follow-up on request. PROMs were assessed at a minimum of one year post presentation and included the QuickDASH, EQ-5D-5L, the Net Promoter Score (NPS) and return to work. There were 221 patients referred to the virtual pathway. The mean age was 41 (range 16–87; SD 18.4 years) and there were 99 men (45%). There were 189 (86%) patients discharged with advice and 19 (9%) patients were recalled for clinical review (seven undisplaced scaphoid fractures, six other acute fractures of the hand or wrist, two scapholunate ligament injuries, and four cases where no abnormality was detected). Thirteen patients (6%) initiated follow-up with the hand service; no fracture or ligament injury was identified within this group. PROMs were available for 179 (81%) patients at a mean of 19 months follow-up (range: 13 – 33 months). The median QuickDASH score was 2.3 (IQR, 0–15.9), the median EQ-5D-5L was 0.85 (IQR, 0.73–1.00), the NPS was 76, and 173 (97%) patients were satisfied with their treatment. There were no documented cases of symptomatic non-union one year following injury. This study reports the introduction of a virtual pathway for suspected scaphoid fractures, demonstrating high levels of patient satisfaction, excellent PROMs, and no detrimental effects in the vast majority of cases

Virtual encounters have experienced an exponential rise amid the current COVID-19 crisis. This abrupt change, seen in response to unprecedented medical and environmental challenges, has been forced upon the orthopaedic community. However, such changes to adopting virtual care and technology were already in the evolution forecast, albeit in an unpredictable timetable impeded by regulatory and financial barriers. This adoption is not meant to replace, but rather augment established, traditional models of care while ensuring patient/provider safety, especially during the pandemic. While our department, like those of other institutions, has performed virtual care for several years, it represented a small fraction of daily care. The pandemic required an accelerated and comprehensive approach to the new reality. Contemporary literature has already shown equivalent safety and patient satisfaction, as well as superior efficiency and reduced expenses with musculoskeletal virtual care (MSKVC) versus traditional models. Nevertheless, current literature detailing operational models of MSKVC is scarce. The current review describes our pre-pandemic MSKVC model and the shift to a MSKVC pandemic workflow that enumerates the conceptual workflow organization (patient triage, from timely care provision based on symptom acuity/severity to a continuum that includes future follow-up). Furthermore, specific setup requirements (both resource/personnel requirements such as hardware, software, and network connectivity requirements, and patient/provider characteristics respectively), and professional expectations are outlined. MSKVC has already become a pivotal element of musculoskeletal care, due to COVID-19, and these changes are confidently here to stay. Readiness to adapt and evolve will be required of individual musculoskeletal clinical teams as well as organizations, as established paradigms evolve. Cite this article: Bone Joint Open 2020;1-6:272–280

Aims. This study aimed to develop a virtual clinic for the purpose of reducing face-to-face orthopaedic consultations. Patients and Methods. Anonymized experts (hip and knee arthroplasty patients, surgeons, physiotherapists, radiologists, and arthroplasty practitioners) gave feedback via a Delphi Consensus Technique. This consisted of an iterative sequence of online surveys, during which virtual documents, made up of a patient-reported questionnaire, standardized radiology report, and decision-guiding algorithm, were modified until consensus was achieved. We tested the patient-reported questionnaire on seven patients in orthopaedic clinics using a ‘think-aloud’ process to capture difficulties with its completion. Results. A patient-reported 13-item questionnaire was developed covering pain, mobility, and activity. The radiology report included up to ten items (e.g. progressive periprosthetic bone loss) depending on the type of arthroplasty. The algorithm concludes in one of three outcomes: review at surgeon’s discretion (three to 12 months); see at next available clinic; or long-term follow-up/discharge. Conclusion. The virtual clinic approach with attendant documents achieved consensus by orthopaedic experts, radiologists, and patients. The robust development and testing of this standardized virtual clinic provided a sound platform for organizations in the United Kingdom to adopt a virtual clinic approach for follow-up of hip and knee arthroplasty patients. Cite this article: Bone Joint J 2019;101-B:951–959

Novel immersive virtual reality (IVR) technologies are revolutionizing medical education. Virtual anatomy education using head-mounted displays allows users to interact with virtual anatomical objects, move within the virtual rooms, and interact with other virtual users. While IVR has been shown to be more effective than textbook learning and 3D computer models presented in 2D screens, the effectiveness of IVR compared to cadaveric models in anatomy education is currently unknown. In this study, we aim to compare the effectiveness of IVR with direct cadaveric bone models in teaching upper and lower limb anatomy for first-year medical students. A randomized, double-blind crossover non-inferiority trial was conducted. Participants were first-year medical students from a single University. Exclusion criteria included students who undertook prior undergraduate or graduate degrees in anatomy. In the first stage of the study, students were randomized in a 1:1 ratio to IVR or cadaveric bone groups studying upper limb skeletal anatomy. All students were then crossed over and used cadaveric bone or IVR to study lower limb skeletal anatomy. All students in both groups completed a pre-and post-intervention knowledge test. The educational content was based on the University of Toronto Medical Anatomy Curriculum. The Oculus Quest 2 Headsets (Meta Technologies) and PrecisionOS Anatomy application (PrecisionOS Technology) were utilized for the virtual reality component. The primary endpoint of the study was student performance on the pre-and post-intervention knowledge tests. We hypothesized that student performance in the IVR groups would be comparable to the cadaveric bone group. 50 first-year medical students met inclusion criteria and were computer randomized (1:1 ratio) to IVR and cadaveric bone group for upper limb skeletal anatomy education. Forty-six students attended the study, 21 completed the upper limb modules, and 19 completed the lower limb modules. Among all students, average score on the pre-intervention knowledge test was 14.6% (Standard Deviation (SD)=18.2%) and 25.0% (SD=17%) for upper and lower limbs, respectively. Percentage increase in students’ scores between pre-and post-intervention knowledge test, in the upper limb for IVR, was 15 % and 16.7% for cadaveric bones (p = 0. 2861), and for the lower limb score increase was 22.6% in the IVR and 22.5% in the cadaveric bone group (p = 0.9356). In this non-inferiority crossover randomized controlled trial, we found no significant difference between student performance in knowledge tests after using IVR or cadaveric bones. Immersive virtual reality and cadaveric bones were equally effective in skeletal anatomy education. Going forward, with advances in VR technologies and anatomy applications, we can expect to see further improvements in the effectiveness of these technologies in anatomy and surgical education. These findings have implications for medical schools having challenges in acquiring cadavers and cadaveric parts

Novel immersive virtual reality (IVR) technologies are revolutionizing medical education. Virtual anatomy education using head-mounted displays allows users to interact with virtual anatomical objects, move within the virtual rooms, and interact with other virtual users. While IVR has been shown to be more effective than textbook learning and 3D computer models presented in 2D screens, the effectiveness of IVR compared to cadaveric models in anatomy education is currently unknown. In this study, we aim to compare the effectiveness of IVR with direct cadaveric bone models in teaching upper and lower limb anatomy for first-year medical students. A randomized, double-blind crossover non-inferiority trial was conducted. Participants were first-year medical students from a single University. Exclusion criteria included students who undertook prior undergraduate or graduate degrees in anatomy. In the first stage of the study, students were randomized in a 1:1 ratio to IVR or cadaveric bone groups studying upper limb skeletal anatomy. All students were then crossed over and used cadaveric bone or IVR to study lower limb skeletal anatomy. All students in both groups completed a pre-and post-intervention knowledge test. The educational content was based on the University of Toronto Medical Anatomy Curriculum. The Oculus Quest 2 Headsets (Meta Technologies) and PrecisionOS Anatomy application (PrecisionOS Technology) were utilized for the virtual reality component. The primary endpoint of the study was student performance on the pre-and post-intervention knowledge tests. We hypothesized that student performance in the IVR groups would be comparable to the cadaveric bone group. 50 first-year medical students met inclusion criteria and were computer randomized (1:1 ratio) to IVR and cadaveric bone group for upper limb skeletal anatomy education. Forty-six students attended the study, 21 completed the upper limb modules, and 19 completed the lower limb modules. Among all students, average score on the pre-intervention knowledge test was 14.6% (Standard Deviation (SD)=18.2%) and 25.0% (SD=17%) for upper and lower limbs, respectively. Percentage increase in students’ scores between pre-and post-intervention knowledge test, in the upper limb for IVR, was 15 % and 16.7% for cadaveric bones (p = 0. 2861), and for the lower limb score increase was 22.6% in the IVR and 22.5% in the cadaveric bone group (p = 0.9356). In this non-inferiority crossover randomized controlled trial, we found no significant difference between student performance in knowledge tests after using IVR or cadaveric bones. Immersive virtual reality and cadaveric bones were equally effective in skeletal anatomy education. Going forward, with advances in VR technologies and anatomy applications, we can expect to see further improvements in the effectiveness of these technologies in anatomy and surgical education. These findings have implications for medical schools having challenges in acquiring cadavers and cadaveric parts

Aims. The aim of this study was to compare the biomechanical models of two frequently used techniques for reconstructing severe acetabular defects with pelvic discontinuity in revision total hip arthroplasty (THA) – the Trabecular Metal Acetabular Revision System (TMARS) and custom triflange acetabular components (CTACs) – using virtual modelling. Methods. Pre- and postoperative CT scans from ten patients who underwent revision with the TMARS for a Paprosky IIIB acetabular defect with pelvic discontinuity were retrospectively collated. Computer models of a CTAC implant were designed from the preoperative CT scans of these patients. Computer models of the TMARS reconstruction were segmented from postoperative CT scans using a semi-automated method. The amount of bone removed, the implant-bone apposition that was achieved, and the restoration of the centre of rotation of the hip were compared between all the actual TMARS and the virtual CTAC implants. Results. The median amount of bone removed for TMARS reconstructions was significantly greater than for CTAC implants (9.07 cm. 3. (interquartile range (IQR) 5.86 to 21.42) vs 1.16 cm. 3. (IQR 0.42 to 3.53) (p = 0.004). There was no significant difference between the median overall implant-bone apposition between TMARS reconstructions and CTAC implants (54.8 cm. 2. (IQR 28.2 to 82.3) vs 56.6 cm. 2. (IQR 40.6 to 69.7) (p = 0.683). However, there was significantly more implant-bone apposition within the residual acetabulum (45.2 cm. 2. (IQR 28.2 to 72.4) vs 25.5 cm. 2. (IQR 12.8 to 44.1) (p = 0.001) and conversely significantly less apposition with the outer cortex of the pelvis for TMARS implants compared with CTAC reconstructions (0 cm. 2. (IQR 0 to 13.1) vs 23.2 cm. 2. (IQR 16.4 to 30.6) (p = 0.009). The mean centre of rotation of the hip of TMARS reconstructions differed by a mean of 11.1 mm (3 to 28) compared with CTAC implants. Conclusion. In using TMARS, more bone is removed, thus achieving more implant-bone apposition within the residual acetabular bone. In CTAC implants, the amount of bone removed is minimal, while the implant-bone apposition is more evenly distributed between the residual acetabulum and the outer cortex of the pelvis. The differences suggest that these implants used to treat pelvic discontinuity might achieve short- and long-term stability through different biomechanical mechanisms. Cite this article: Bone Joint J 2024;106-B(5 Supple B):74–81

INTRODUCTION. Simulation plays an important role in surgical education and the ability to perfect surgical performance. Simulation can be enhanced by adding various layers of realism to the experience. Haptic feedback enhances the simulation experience by providing tactile responses and virtual reality imagery provides an immersive experience and allows for greater appreciation of three-dimensional structures. In this study, we present a proof-of-concept haptic simulator to replicate key steps of a cervical laminoplasty procedure. The technology uses affordable components and is easily modifiable so that it can be used from novice through to expert level. Custom models can be easily added ensuring the simulator can be used in a wide range of orthopaedic applications from baseline education through to day of surgery pre-operative simulation. METHOD. We used the Unity Game Engine, the 3D Systems “Touch” Haptic Feedback Device (HFD), and a Meta Quest VR headset. Our system uses a number of complex algorithms to track the shape and provide haptic feedback of a virtual bone model. This allows for simulation of various tools including a high-speed burr, Kerrison rongeur and intraoperative X-rays. RESULTS. Our simulator replicates the tactile sensations of bone-burring tasks. Although we focused on the cervical laminoplasty procedure, the system can load data from CT scans, enabling the simulation of multiple other procedures. The parts cost of our system, $10,000 NZD, is a fraction of the cost of traditional surgical simulators. DISCUSSION. Our simulator reduces financial barriers to accessing orthopaedic simulators. Trainees can perform hands-on practice without compromising patient safety. The immersive nature of VR, combined with realistic haptic feedback, enables trainees to develop the dexterity and three-dimensional understanding of detailed bony work. Further refinements are needed before we can perform validation studies on our system. CONCLUSIONS. We present an affordable surgical simulator capable of simulating bony surgical procedures in a VR environment using haptic feedback technology and consumer-grade components. ACKNOWLEDGEMENTS. This research was made possible by the generosity of the Wishbone Trust

Abstract. Objectives. Non-technical skills including teamwork play a pivotal role in surgical outcomes. Virtual reality is effective at improving technical skills, however there is a paucity of evidence on team-based virtual reality (VR) training. This study aimed to assess if multiplayer virtual reality training was superior to solo training for acquisition of both technical and non-technical skills in learning the complex anterior approach total hip arthroplasty operation. Methods. 10 novice surgeons and 10 novice scrub nurses, were randomised to solo or team virtual reality training to perform anterior approach total hip arthroplasty. Solo participants trained with virtual avatar counterparts, whilst teams trained in pairs (surgeon and scrub nurse). Both groups underwent 5 VR training sessions over 6 weeks. Then, they underwent a real-life assessment in which they performed AA-THA on a high-fidelity model with real equipment in a simulated operating theatre. Teams performed together and solo participants were randomly paired up with a solo player of the opposite role. Videos of the assessment were marked by two blinded expert assessors. Outcomes were procedure time, procedural errors from an expert pre-defined protocol and acetabular component positioning. Non-technical skills were assessed using the NOTECHs II and NOTSS scores. Results. Teams were 28.11% faster than solos in the real world assessment (31.22 minutes ±2.02 vs 43.43 ±2.71, p=0.01), with 34.91% less errors (−15.25 errors ±3.09 vs −23.43 ±1.84, p=0.04). Teams had significantly higher NOTSS and NOTECHS II scores when compared to solos (p<0.001). 8/10 surgeons placed the acetabular component within the target safe zone. Conclusions. Multiplayer training appears to lead to faster surgery with fewer technical errors and the development of superior non-technical skills. VR learnt skills appear to translate to the physical world. This supports the application of multidisciplinary learning to create a more integrated approach to surgical team training

The British Orthopedic Association recommends that patients referred to fracture clinic are reviewed within 72 hours. With the increase in referrals and limited clinic capacity it is becoming increasingly difficult to see every referral with in a 72 hour time frame. Some patients are waiting 2 weeks or more before they can be seen in a fracture clinic. With the aim of improving care by seeking to meet BOAST 7 target, waiting times for fracture clinic appointments at the Homerton University Hospital were audited prospectively against this national guideline, before virtual fracture clinic was implemented and 6 weeks after the implementation of virtual fracture clinic at our hospital. Virtual fracture clinic is where an Orthopedic consultant reviews a patients x-rays and A&E documentation and decides if that patients needs to be seen in a face to face fracture clinic to discuss operative vs. non-operative management of their injury or if a treatment plan can be delivered without the patient having to come back to hospital. The study was conducted as a prospective closed-loop audit in which the second cycle took place after the implementation of the new virtual fracture clinic service. The first cycle showed a non-compliant waiting time with only 18% of patients being seen within 72 hours. Following the implementation of virtual fracture clinic, 84% of all patients were reviewed within 72 hours. Virtual fracture clinic delivered a significant reduction in waiting times. Virtual fracture clinic has only just been implemented at the Homerton University Hospital and hopefully at the next audit we will be 100% compliant with the BOA BOAST 7 Guideline. We would recommend that virtual fracture clinics being rolled out in Orthopedic departments in all hospitals which have Orthopedic services

Background. Due to the overwhelming demand for trauma services, resulting from increasing emergency department attendances over the past decade, virtual fracture clinics (VFCs) have become the fashion to keep up with the demand and help comply with the BOA Standards for Trauma and Orthopaedics (BOAST) guidelines. In this article, we perform a systematic review asking, “How useful are VFCs?”, and what injuries and conditions can be treated safely and effectively, to help decrease patient face to face consultations. Our primary outcomes were patient satisfaction, clinical efficiency and cost analysis, and clinical outcomes. Methods. We performed a systematic literature search of all papers pertaining to VFCs, using the search engines PubMed, MEDLINE, and the Cochrane Database, according to the Preferred Reporting Items for Systematic review and Meta-Analysis (PRISMA) checklist. Searches were carried out and screened by two authors, with final study eligibility confirmed by the senior author. Results. In total, 21 records were relevant to our research question. Six orthopaedic injuries were identified as suitable for VFC review, with a further four discussed in detail. A reduction of face to face appointments of up to 50% was reported with greater compliance to BOAST guidelines (46.4%) and cost saving (up to £212,000). Conclusions. This systematic review demonstrates that the VFC model can help deliver a safe, more cost-effective, and more efficient arm of the trauma service to patients. Cite this article: Bone Joint Open 2020;1-11:683–690

Patient education programmes prior to hip and knee arthroplasty reduce anxiety and create realistic expectations. While traditionally delivered in-person, the Covid-19 pandemic has necessitated change to remote delivery. We describe a ‘Virtual Joint School’ (VJS) model introduced at Ysbyty Gwynedd, and present patient feedback to it. Eligible patients first viewed online educational videos created by our Multi-Disciplinary Team (MDT); and then attended an interactive virtual session where knowledge was reinforced. Each session was attended by 8–10 patients along with a relative/friend; and was hosted by the MDT consisting of nurses, physiotherapists, occupational therapists, and a former patient who provided personal insight. Feedback on the VJS was obtained prospectively using an electronic questionnaire. From July 2022 to February 2023, 267 patients attended the VJS; of which 117 (44%) responded to the questionnaire. Among them, 87% found the pre-learning videos helpful and comprehensible, 92% felt their concerns were adequately addressed, 96% felt they had sufficient opportunity to ask questions and 96% were happy with the level of confidentiality involved. While 83% felt they received sufficient support from the health board to access the virtual session, 63% also took support from family/friends to attend it. Only 15% felt that they would have preferred a face-to-face format. Finally, by having ‘virtual’ sessions, each patient saved, on average, 38 miles and 62 minutes travel (10,070 miles and 274 hours saved for 267 patients). Based on the overwhelmingly positive feedback, we recommend implementation of such ‘Virtual Joint Schools’ at other arthroplasty centres as well

Superior teamwork in the operating theatre is associated with improved technical performance and clinical outcomes. Yet modern rota patterns, workforce shortages, and increasing complexity of surgery, means that there is less familiarity between staff and the required choreography. Immersive Virtual Reality (iVR) can successfully train surgical staff individually, however iVR team training has yet to be investigated. We aimed to design a multiplayer iVR platform for anterior approach total hip arthroplasty (AA-THA) and assess if multiplayer iVR training was superior to single player training for acquisition of both technical and non-technical skills. An iVR platform with choreographed roles for the surgeon and scrub nurse was developed using Cognitive Task Analysis. Forty participants were randomised to individual or team iVR training. Individually- trained participants practiced alongside virtual avatar counterparts, whilst teams trained live in pairs. Both groups underwent five iVR training sessions over 6-weeks. Subsequently, they underwent a real-life assessment in which they performed AA-THA on a high-fidelity model with real equipment in a simulated theatre. Teams performed together and individually trained participants were randomly paired up. Videos were marked by two blinded assessors recording the NOTSS, NOTECHS II and SPLINTS scores - validated technical and non-technical scores assessing surgeon and scrub nurse skills. Secondary outcomes were procedure time and number of technical errors. Teams outperformed individually trained participants for non-technical skills in the real-world assessment (NOTSS 13.1 ± 1.5 vs 10.6 ± 1.6, p =0.002, NOTECHS-II score 51.7 ± 5.5 vs 42.3 ± 5.6, p=0.001 and SPLINTS 10 ± 1.2 vs 7.9 ± 1.6, p = 0.004). They completed the assessment 28.1% faster (27.2 minutes ± 5.5 vs 41.8 ±8.9, p<0.001), and made fewer than half the number of technical errors (10.4 ± 6.1 vs 22.6 ± 5.4, p<0.001). Multiplayer training leads to faster surgery with fewer technical errors and the development of superior non-technical skills for anterior approach total hip arthroplasty. The convention of surgeons and nurses training separately, but undertaking real complex surgery together, can be supplanted by team training, delivered through immersive virtual reality

Aims. Paediatric fractures are highly prevalent and are most often treated with plaster. The application and removal of plaster is often an anxiety-inducing experience for children. Decreasing the anxiety level may improve the patients’ satisfaction and the quality of healthcare. Virtual reality (VR) has proven to effectively distract children and reduce their anxiety in other clinical settings, and it seems to have a similar effect during plaster treatment. This study aims to further investigate the effect of VR on the anxiety level of children with fractures who undergo plaster removal or replacement in the plaster room. Methods. A randomized controlled trial was conducted. A total of 255 patients were included, aged five to 17 years, who needed plaster treatment for a fracture of the upper or lower limb. Randomization was stratified for age (five to 11 and 12 to 17 years). The intervention group was distracted with VR goggles and headphones during the plaster treatment, whereas the control group received standard care. As the primary outcome, the post-procedural level of anxiety was measured with the Child Fear Scale (CFS). Secondary outcomes included the children’s anxiety reduction (difference between CFS after and CFS before plaster procedure), numerical rating scale (NRS) pain, NRS satisfaction of the children and accompanying parents/guardians, and the children’s heart rates during the procedure. An independent-samples t-test and Mann-Whitney U test (depending on the data distribution) were used to analyze the data. Results. The post-procedural CFS was significantly lower (p < 0.001) in the intervention group (proportion of children with no anxiety = 78.6%) than in the control group (56.8%). The anxiety reduction, NRS pain and satisfaction scores, and heart rates showed no significant differences between the control group and the intervention group. Subanalyses showed an increased effect of VR on anxiety levels in young patients, females, upper limb fractures, and those who had had previous plaster treatment. Conclusion. VR effectively reduces the anxiety levels of children in the plaster room, especially in young girls. No statistically significant effects were seen regarding pain, heart rate, or satisfaction scores. Cite this article: Bone Joint J 2024;106-B(7):728–734

Current evidence suggests that superior surgical team performance is linked to fewer intra-operative errors, reductions in mortality and even improved patient outcomes. Virtual reality has demonstrated excellent efficacy in training surgeons and scrub nurses individually, however its impact on training teams is currently unknown. This study aimed to assess if training together (scrub nurse and surgeon) in an innovative multiplayer virtual reality program was superior to single player training for novices learning anterior approach total hip arthroplasty (AA-THA). 40 participants (20 novice surgeons (CT1-ST3 level) and 20 novice scrub nurses) were enrolled in this study and randomised to individual or team virtual reality training. Individually-trained participants played with virtual avatar counterparts, whilst teams trained live in pairs (surgeon and scrub nurse). Both groups underwent 5 VR training sessions over 6 weeks. Subsequently, they underwent a real-life assessment in which they performed AA-THA on a high-fidelity model with real equipment in a simulated operating theatre. Teams performed together and individually-trained participants were randomly paired up with a solo player of the opposite role. Videos of the assessment were marked by two blinded expert assessors. The primary outcome was team performance as graded by the validated NOTECHs II score. Secondary outcomes were procedure time and number of technical errors from an expert pre-defined protocol. Teams outperformed individually-trained participants for non-technical skills in the real-world assessment (NOTECHS-II score 50.3 ± 6.04 vs 43.90 ± 5.90, p=0.0275). They completed the assessment 28.1% faster (31.22 minutes ±2.02 vs 43.43 ±2.71, p=0.01), and made close to half the number of technical errors when compared to the individual group (12.9 ± 8.3 vs 25.6 ± 6.1, p=0.001). Multiplayer, team training appears to lead to faster surgery with fewer technical errors and the development of superior non-technical skills

Aims. The aim of this study was to assess the current evidence relating to the benefits of virtual reality (VR) simulation in orthopaedic surgical training, and to identify areas of future research. Materials and Methods. A literature search using the MEDLINE, Embase, and Google Scholar databases was performed. The results’ titles, abstracts, and references were examined for relevance. Results. A total of 31 articles published between 2004 and 2016 and relating to the objective validity and efficacy of specific virtual reality orthopaedic surgical simulators were identified. We found 18 studies demonstrating the construct validity of 16 different orthopaedic virtual reality simulators by comparing expert and novice performance. Eight studies have demonstrated skill acquisition on a simulator by showing improvements in performance with repeated use. A further five studies have demonstrated measurable improvements in operating theatre performance following a period of virtual reality simulator training. Conclusion. The demonstration of ‘real-world’ benefits from the use of VR simulation in knee and shoulder arthroscopy is promising. However, evidence supporting its utility in other forms of orthopaedic surgery is lacking. Further studies of validity and utility should be combined with robust analyses of the cost efficiency of validated simulators to justify the financial investment required for their use in orthopaedic training. Cite this article: Bone Joint J 2018;100-B:559–65

Background. Chronic low back pain (CLBP) is the leading cause of disability worldwide. Immersive virtual reality (IVR) can be delivered using head mounted display (HMD) to interact with 3D virtual environment (VE). IVR has shown promising results in management of chronic pain conditions, using different mechanisms (e.g., exposure to movement and distraction). However, it has not been widely tested for CLBP. Future development of IVR intervention needs inputs from gatekeepers to determine key considerations, facilitators and barriers. This qualitative study aimed to explore views and opinions of physiotherapists about IVR intervention for adults with CLBP. Methods. Four focus groups were conducted online, with 16 physiotherapists. A demonstration of existing IVR mechanisms was presented. The data were transcribed and analysed through descriptive thematic analysis. Results. IVR was thought to be a suitable adjunct for a subgroup of patients who are reluctant to engage with standard care. Motivation to perform challenging physical tasks was believed to be a potential benefit. Safety, possibility of addiction, and transferability of acquired skills from VE to ‘real world’ and hygiene were concerns and the intervention was preferred to be used under clinical supervision. VE personalisation to patient's goal and preference with delivery and progression being gradual depending upon patient's abilities was suggested. Technical knowledge was seen as a facilitator, while cost and technology acceptance were barriers for future implementation. Conclusion. Future studies would need to consider the reported views of physiotherapists to inform development and implementation of IVR intervention for CLBP. Conflicts of interest: No conflict of interest. Sources of funding: Funded by the government of Saudi Arabia

Hip precautions following total hip arthroplasty (THA) limits flexion, adduction and internal rotation, yet these precautions cause unnecessary psychological stress. This study aims to assess bony and implant impingement using virtual models from actual patient's bony morphology and spinopelvic parameters to deduce whether hip precautions are necessary with precise implant positioning in the Asian population. Individualized sitting and standing sacral slope data of robotic THAs performed at two tertiary referral centers in Hong Kong was inputted into the simulation system based on patients’ pre-operative sitting and standing lumbar spine X-rays. Three-dimensional dynamic models were reconstructed using the Stryker Mako THA 4.0 software to assess bony and implant impingement both anteriorly and posteriorly, with default cup placement at 40° inclination and 20° anteversion. Femoral anteversion followed individual patient's native version. A 36mm hip ball was chosen for all cups equal or above 48mm and 32mm for those below. Anterior impingement was assessed by hip flexion and posterior impingement was assessed by hip extension. 113 patients were included. At neutral rotation and adduction, no patients had anterior implant impingement at hip flexion of 100°. 1.7% had impingement at 110°, 3.5% had impingement at 120°, 9.7% had impingement at 130°. With 20° of internal rotation and adduction, 0.8% had anterior implant impingement at hip flexion of 90°, 7.1% had impingement at 100° and 18.5% had impingement at 110°. With the hip externally rotated by 20°, 0.8% of patients had posterior implant impingement, and 8.8% bony impingement at 0° extension. With enabling technology allowing accurate component positioning, hip precautions without limiting forward flexion in neutral position is safe given precise implant positioning and adequate osteophyte removal. Patients should only be cautioned about combined internal rotation, adduction with flexion

Introduction. Local commissioning groups are no longer funding outpatient follow up of joint replacements in an effort to save money. We present the costs of changing from traditional follow up methods to a virtual clinic at Warwick Hospital. Before September 2014 all joint replacements were seen in outpatients at six weeks, one year, five years, ten years and then every two years thereafter. They were usually reviewed, in a non-consultant led clinic, by a Band 7 specialist physiotherapist. This cost approximately £50 per patient including x-ray. Occasionally, the patients were seen in a consultant led clinic costing approximately £100. Methods and Results. Currently patients are reviewed in outpatients at six weeks and one-year post operation by a specialist physiotherapist. Patients over the age of 75 years (at time of surgery) are then discharged to the care of their GP. Patients under the age of 75 enter the virtual clinic. They receive an Oxford Hip/Knee Score and x-ray at seven years post op then every three years after. In order to set up and maintain the virtual clinic a midpoint band 3 administrator was employed. Based on 3000 follow up episodes per year the cost of administrating the database is £7 per patient; however this will vary dependent on actual activity. The cost of a virtual appointment with a specialist physiotherapist who will review the Oxford Hip/Knee Score and an x-ray is approximately £40 including x-ray. The total cost of a virtual clinic follow up is therefore approximately £47. Conclusion. Virtual clinics do not save large amounts of money compared to outpatient follow up by specialist physiotherapists and may actually cost more if significant numbers of patients need to be brought back to clinic. They incur significant administration costs (including set up) but do free up outpatient availability to see new patients

Spinal stenosis is a condition resulting in the compression of the neural elements due to narrowing of the spinal canal. Anatomical factors including enlargement of the facet joints, thickening of the ligaments, and bulging or collapse of the intervertebral discs contribute to the compression. Decompression surgery alleviates spinal stenosis through a laminectomy involving the resection of bone and ligament. Spinal decompression surgery requires appropriate planning and variable strategies depending on the specific situation. Given the potential for neural complications, there exist significant barriers to residents and fellows obtaining adequate experience performing spinal decompression in the operating room. Virtual teaching tools exist for learning instrumentation which can enhance the quality of orthopaedic training, building competency and procedural understanding. However, virtual simulation tools are lacking for decompression surgery. The aim of this work was to develop an open-source 3D virtual simulator as a teaching tool to improve orthopaedic training in spinal decompression. A custom step-wise spinal decompression simulator workflow was built using 3D Slicer, an open-source software development platform for medical image visualization and processing. The procedural steps include multimodal patient-specific loading and fusion of Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) data, bone threshold-based segmentation, soft tissue segmentation, surgical planning, and a laminectomy and spinal decompression simulation. Fusion of CT and MRI elements was achieved using Fiducial-Based Registration which aligned the scans based on manually placed points allowing for the identification of the relative position of soft and hard tissues. Soft tissue segmentation of the spinal cord, the cerebrospinal fluid, the cauda equina, and the ligamentum flavum was performed using Simple Region Growing Segmentation (with manual adjustment allowed) involving the selection of structures on T1 and/or T2-weighted scans. A high-fidelity 3D model of the bony and soft tissue anatomy was generated with the resulting surgical exposure defined by labeled vertebrae simulating the central surgical incision. Bone and soft tissue resecting tools were developed by customizing manual 3D segmentation tools. Simulating a laminectomy was enabled through bone and ligamentum flavum resection at the site of compression. Elimination of the stenosis enabled decompression of the neural elements simulated by interpolation of the undeformed anatomy above and below the site of compression using Fill Between Slices to reestablish pre-compression neural tissue anatomy. The completed workflow allows patient specific simulation of decompression procedures by staff surgeons, fellows and residents. Qualitatively, good visualization was achieved of merged soft tissue and bony anatomy. Procedural accuracy, the design of resecting tools, and modeling of the impact of bone and ligament removal was found to adequately encompass important challenges in decompression surgery. This software development project has resulted in a well-characterized freely accessible tool for simulating spinal decompression surgery. Future work will integrate and evaluate the simulator within existing orthopaedic resident competency-based curriculum and fellowship training instruction. Best practices for effectively teaching decompression in tight areas of spinal stenosis using virtual simulation will also be investigated in future work

Introduction. Virtual fracture clinics (VFC's) aim to reduce the number of outpatient appointments while improving the clinical effectiveness and patients experience through standardisation of treatment pathways. With 4.6% of ED admissions due to trauma the VFC prevents unnecessary face to face appointments providing a cost savings benefit to the NHS. Methods. This project demonstrates the importance of efficient VFC process in reducing the burden on the fracture clinics. We completed preformed a retrospective cross-sectional study, analysing two cycles in May (n=305) and September (n=332) 2021. We reviewed all VFC referrals during this time assessing the quality of the referral, if they went on to require a face to face follow up and who the referring health care professional was. Following the cycle in May we provided ongoing education to A&E staff before re-auditing in September. Results. Between the two cycles there was an average 19% improvement in quality of the referrals, significant reduction in number of inappropriate referrals for soft tissue knee and shoulder injuries from 15.1% (n=50) to 4.5% (n=15) following our intervention. There was an 8% increase in number of fracture clinic appointments to 74.4% (n=247), primarily due to an increase number of referrals from nurse practitioners. Radial head fractures were targeted as one group that were able to be successfully managed in VFC, despite this 64% (n=27) of patients were still seen in the outpatient department following VFC referral. Conclusion. Despite the decrease in the number of inappropriate referrals, and the increase in quality of referrals following our intervention. The percentage of VFC referrals in CAVUHB is still higher than other centres in with established VFCs in England. This possibly highlights the need for further education to emergency staff around describing what injuries are appropriate for referral, specifically soft tissue injuries and radial head fractures. In order to optimise the VFC process and provide further cost savings benefits while reducing the strain on fracture clinics

Currently, hip implant designs are evaluated experimentally using mechanical simulators or cadavers, and total hip arthroplasty (THA) postoperative outcomes are evaluated clinically using long-term follow-up. However, these evaluation techniques can be both costly and time-consuming. Neither can provide an assessment of post-operative results at the onset of implant development. More recently, a forward-solution mathematical model was developed that functions as theoretical joint simulator, providing instant feedback to designers and surgeons alike. This model has been validated by comparing the model predictions with kinematic results from fluoroscopy for both implanted and non-implanted hips and kinetics from a telemetric hip. The model allows surgical technique modifications and implant component placement under in vivo conditions. The objective of this study was to further expand the capabilities of the model to function as an intraoperative virtual surgical tool (Figure 1). This new module allows the surgeon to simulate surgery, then predict, compare, and optimize postoperative THA outcomes based on component placement, sizing choices, reaming and cutting locations, and surgical methods. This virtual surgery tool simulates the quadriceps, hamstring, gluteus, iliopsoas, tensor fasciae latae, and an adductor muscle groups, as well as the hip capsular ligament groups. The model can simulate resecting, weakening, loosening, or tightening of soft tissues based on surgical techniques. Additionally, the model can analyze a variety of activities, including gait and deep flexion activities. Initially, the virtual surgery module offers theoretical surgery tools that allow surgeons to alter surgical alignments, component designs, offsets, as well as reaming and cutting simulations. The virtual model incorporates a built-in CT scan bone database which will assist in determining muscle and ligament attachment sites as well as bony landmarks. The virtual model can be used to assist in the placement of both the femoral component and the acetabular cup (Figure 2). Moreover, once the surgeon has decided on the placements of the components, they can use the simulation capabilities to run virtual human body maneuvers based on the chosen parameters. The simulations will reveal force, contact stress, and motion predictions of the hip joint (Figure 3). The surgeon can then choose to modify the positions accordingly or proceed with the surgery. This new virtual surgical tool will allow surgeons to gain a better understanding of possible post-operative outcomes under pre-operative conditions or intra-operatively. Simulations using the virtual surgery model has revealed that improper component placement may lead to non-ideal post-operative function, which has been simulated using the model. Further evaluation is ongoing so that this new module can reveal more information pre-operatively, allowing a surgeon to gain ample information before surgery, especially with difficult and revision cases

Superior team performance in surgery leads to fewer technical errors, reduced mortality, and improved patient outcomes. Scrub nurses are a pivotal part of this team, however they have very little structured training, leading to high levels of stress, low confidence, inefficiency, and potential for harm. Immersive virtual reality (iVR) simulation has demonstrated excellent efficacy in training surgeons. We tested the efficacy of an iVR curriculum for training scrub nurses in performing their role in an anterior approach total hip arthroplasty (AA-THA). Sixty nursing students were included in this study and randomised in a 1:1 ratio to learning the scrub nurse role for an AA-THA using either conventional training or iVR. The training was derived through expert consensus with senior surgeons, scrub nurses and industry reps. Conventional training consisted of a 1-hour seminar and 2 hours of e-learning where participants were taught the equipment and sequence of steps. The iVR training involved 3 separate hour-long sessions where participants performed the scrub nurse role with an avatar surgeon in a virtual operation. The primary outcome was their performance in a physical world practical objective assessment with real equipment. Data were confirmed parametric using the Shapiro-Wilk test and means compared using the independent samples student's t-test. 53 participants successfully completed the study (26 iVR, 27 conventional) with a mean age of 31±9 years. There were no significant differences in baseline characteristics or baseline knowledge test scores between the two groups (p>0.05). The iVR group significantly outperformed the conventionally trained group in the real-world assessment, scoring 66.9±17.9% vs 41.3±16.7%, p<0.0001. iVR is an easily accessible, low cost training modality which could be integrated into scrub nursing curricula to address the current shortfall in training. Prolonged operating times are strongly associated with an increased risk of developing serious complications. By upskilling scrub nurses, operations may proceed more efficiently which in turn may improve patient safety

Objectives. To assess the clinical and cost-effectiveness of a virtual fracture clinic (VFC) model, and supplement the literature regarding this service as recommended by The National Institute for Health and Care Excellence (NICE) and the British Orthopaedic Association (BOA). Methods. This was a retrospective study including all patients (17 116) referred to fracture clinics in a London District General Hospital from May 2013 to April 2016, using hospital-level data. We used interrupted time series analysis with segmented regression, and direct before-and-after comparison, to study the impact of VFCs introduced in December 2014 on six clinical parameters and on local Clinical Commissioning Group (CCG) spend. Student’s t-tests were used for direct comparison, whilst segmented regression was employed for projection analysis. Results. There were statistically significant reductions in numbers of new patients seen face-to-face (140.4, . sd. 39.6 versus 461.6, . sd. 61.63, p < 0.0001), days to first orthopaedic review (5.2, . sd. 0.66 versus 10.9, . sd. 1.5, p < 0.0001), discharges (33.5, . sd. 3.66 versus 129.2, . sd. 7.36, p < 0.0001) and non-attendees (14.82, . sd. 1.48 versus 60.47, . sd. 2.68, p < 0.0001), in addition to a statistically significant increase in number of patients seen within 72-hours (46.4% 3873 of 8345 versus 5.1% 447 of 8771, p < 0.0001). There was a non-significant increase in consultation time of 1 minute 9 seconds (14 minutes 53 seconds . sd. 106 seconds versus 13 minutes 44 seconds . sd. 128 seconds, p = 0.0878). VFC saved the local CCG £67 385.67 in the first year and is set to save £129 885.67 annually thereafter. Conclusions. We have shown VFCs are clinically and cost-effective, with improvement across several clinical performance parameters and substantial financial savings for CCGs. To our knowledge this is the largest study addressing clinical practice implications of VFCs in England, using robust methodology to adjust for pre-existing trends. Further studies are required to appreciate whether our results are reproducible with local variations in the VFC model and payment tariffs. Cite this article: A. McKirdy, A. M. Imbuldeniya. The clinical and cost effectiveness of a virtual fracture clinic service: An interrupted time series analysis and before-and-after comparison. Bone Joint Res 2017;6:–269. DOI: 10.1302/2046-3758.65.BJR-2017-0330.R1

Background. In certain clinical situations, complex local anatomy and limitations of surgical exposure can make adequate and bone tumor ablation, resection and reconstruction very challenging. We wished to review our clinical experience and accuracy achieved with entirely virtually planned single stage tumor ablation/resection and reconstructions. Methods. We report 6 cases of bone tumors in which tumor removal (by radio-frequency (RF) ablation and/or resection) and subsequent reconstruction were based entirely on pre-operative virtual analysis and planning. All interventions were accomplished with specifically designed and pre-operatively manufactured 3D-printed drill & resection guides. Immediate subsequent defect reconstruction was either performed with a precisely matching allograft (n=1) or composite metal implant (n=5) consisting of a defect specific titanium scaffold and multiple integrated fixation features to provide optimal immediate stability as well as subsequent opportunity for osseointegration. We reviewed the sequence of all procedural steps as well as the accuracy of each saw blade or drill trajectory by direct intra-operative measurement, post-operative margin status and virtual comparison of pre- and post-operative CT scans. Results. Intra-operative application/assembly of the resection guides could be accomplished with relative ease in all cases, permitting quick and efficient reproduction of the planned osteotomies as well as RF-probe trajectories with a high degree of accuracy. Histologically all resection margins were negative as planned except in one case where one pelvic resection was extended due to intraoperative concern of possible local tumor progression. All implants could be placed as planned, with post-operative imaging demonstrating satisfactory implant position. Virtual analysis of post-operative CT scans confirmeded minimal deviation of final implant position from the pre-operative plan. Conclusion. Reliable, accurate placement of tumor biopsy/ablation tracts and resection planes and their optimal alignment with respect to critical structures, tumor extent and desired preservation of unaffected bone is the most challenging and time consuming step during the analysis and planning phase. However it is also the crucial step with regard to subsequent design and production of clinically and oncologically meaningful case-specific drill/resection guides and implants. If these prerequisites are met, computer assisted virtual planning along with 3Dprinting-technology can afford high intraoperative accuracy, contribute to increased intra-operative surgeon confidence and decreased operative time

Purpose of the study: We describe a surgery navigation system based on virtual fluoroscopy images established with a 3D optic localizer. The purpose of this work was to check the accuracy of the system for posterior spinal implants in comparison with conventional surgery. Duration of radiation and duration of surgery were compared. Material and methods: A 3D optic localizer was used to monitor the position of the instruments in the operative field, as well as the fluoroscopy receptor. The surgeon took two views, ap and lateral, with a total exposure of two seconds. The C arm was then removed. After image correction, the ap and lateral views were displayed on the work station screen where the computer superimposed to tools on each image. Twenty osteosynthesis procedures for implantation of pedicular screws via a posterior approach to the thoracolumbar spine were performed with this virtual fluoroscopy technique (20 patients, 68 screws). During the same study period, twenty other procedures were performed with the conventional technique (ap and lateral x-ray with the C-arm after drilling the pedicle, 20 patients, 72 screws). The position of the spinal implants was compared between the two series on the ap and lateral views and postoperative CT. Similarly time of exposure to x-rays and duration of the surgical procedure were recorded. Results: The rate of strictly intrapedicular implantation was less than 8% (5/68 screws) in the virtual fluoroscopy series versus 15% (11/72 screws) in the conventional series. Time of exposure to radiation was significantly lower in the virtual fluoroscopy series with a 1 to 3 improvement (3.5 s versus 11.5 s on average) over the conventional method. With training, this method is not more time consuming (10 min per screw for the conventional method versus 11.25 min for virtual fluoroscopy). Discussion and conclusion: Compared with conventional fluoroscopy, the virtual technique enables real time navigation while significantly reducing the dose of radiation, both for the patient and the surgery team. There are two types of advantages of virtual fluoroscopy over CT-based systems: first virtual fluoroscopy is immediately available without specific preoperative imaging and secondly it provides real non-magnified images acquired once during the procedure, after which the C-arm is removed. 3D virtual fluoroscopy is probably the next step but requires further experience

Paediatric musculoskeletal (MSK) disorders often produce severe limb deformities, that may require surgical correction. This may be challenging, especially in case of multiplanar, multifocal and/or multilevel deformities. The increasing implementation of novel technologies, such as virtual surgical planning (VSP), computer aided surgical simulation (CASS) and 3D-printing is rapidly gaining traction for a range of surgical applications in paediatric orthopaedics, allowing for extreme personalization and accuracy of the correction, by also reducing operative times and complications. However, prompt availability and accessible costs of this technology remain a concern. Here, we report our experience using an in-hospital low-cost desk workstation for VSP and rapid prototyping in the field of paediatric orthopaedic surgery. From April 2018 to September 2022 20 children presenting with congenital or post-traumatic deformities of the limbs requiring corrective osteotomies were included in the study. A conversion procedure was applied to transform the CT scan into a 3D model. The surgery was planned using the 3D generated model. The simulation consisted of a virtual process of correction of the alignment, rotation, lengthening of the bones and choosing the level, shape and direction of the osteotomies. We also simulated and calculated the size and position of hardware and customized massive allografts that were shaped in clean room at the hospital bone bank. Sterilizable 3D models and PSI were printed in high-temperature poly-lactic acid (HTPLA), using a low-cost 3D-printer. Twenty-three operations in twenty patients were performed by using VSP and CASS. The sites of correction were: leg (9 cases) hip (5 cases) elbow/forearm (5 cases) foot (5 cases) The 3D printed sterilizable models were used in 21 cases while HTPLA-PSI were used in five cases. customized massive bone allografts were implanted in 4 cases. No complications related to the use of 3D printed models or cutting guides within the surgical field were observed. Post-operative good or excellent radiographic correction was achieved in 21 cases. In conclusion, the application of VSP, CASS and 3D-printing technology can improve the surgical correction of complex limb deformities in children, helping the surgeon to identify the correct landmarks for the osteotomy, to achieve the desired degree of correction, accurately modelling and positioning hardware and bone grafts when required. The implementation of in-hospital low-cost desk workstations for VSP, CASS and 3D-Printing is an effective and cost-advantageous solution for facilitating the use of these technologies in daily clinical and surgical practice

We created virtual three-dimensional reconstruction models from computed tomography scans obtained from patients with acetabular fractures. Virtual cylindrical implants were placed intraosseously in the anterior column, the posterior column and across the dome of the acetabulum. The maximum diameter which was entirely contained within the bone was determined for each position of the screw. In the same model, the cross-sectional diameters of the columns were measured and compared to the maximum diameter of the corresponding virtual implant. We found that the mean maximum diameter of virtual implant accommodated by the anterior columns was 6.4 mm and that the smallest diameter of the columns was larger than the maximum diameter of the equivalent virtual implant. This study suggests that the size of the screw used for percutaneous fixation of acetabular fractures should not be based solely on the measurement of cross-sectional diameter and that virtual three-dimensional reconstructions might be useful in pre-operative planning

Background. Immersive virtual reality (VR) demonstrates potential benefits in patients with chronic low back pain (CLBP). However, few studies have investigated the feasibility and the acceptability of introducing immersive VR for use with patients with CLBP and in the Kingdom of Saudi Arabia (KSA). Aim. To investigate immersive VR's feasibility, tolerability, and acceptability as a rehabilitation intervention for adult patients with CLBP and explore the views of relevant Health Care Practitioners (HCPs) in the KSA. Methodology and Methods. A multi-centre, mixed-methods, explanatory sequential design was adopted to test immersive VR's feasibility, tolerability, and acceptability. An uncontrolled feasibility trial was conducted. The immersive VR intervention involved a training session followed by three sessions over one week using commercially available hardware and software. Feasibility outcomes were collected from patients immediately post-intervention. Patients and HCPs were recruited for semi-structured interviews. Results. Thirty-three patients and three HCPs were recruited. The feasibility a priori criteria were met for recruitment, retention, dropout, completeness of questionnaire data, treatment compliance and fidelity. Adverse events included one who reported aggravation of tinnitus, whereas two experienced dizziness. Qualitative data suggested that entertainment and motivation were key enablers. Barriers included technological capability and HCPs’ perceptions that immersive VR was time-consuming. Conclusion. The results suggested that immersive VR was feasible, acceptable, and tolerable among patients with CLBP and HCPs in clinical settings in the KSA. Further research focusing on the effectiveness is warranted in this field. Conflicts of Interest. None. Sources of Funding. None. Trial registration number. ISRCTN14434517

Introduction. Decreases in trainees' working hours, coupled with evidence of worse outcomes when hip arthroscopies are performed by inexperienced surgeons, mandate the development of additional means of arthroscopic training. Though virtual reality simulation training has been adopted by other surgical specialities, its slow uptake in arthroscopic training is due to a lack of evidence as to its benefits. These benefits can be demonstrated through learning curves associated with simulator training – with practice reflecting measurable increases in validated performance metrics. Materials & Methods. Twenty-five medical students completed seven simulated arthroscopies of a healthy virtual hip joint in the supine position on a simulator previously shown to have construct validity. Twelve targets had to be visualised within the central compartment; six via the anterior portal, three via the anterolateral portal and three via the posterolateral portal. Eight students proceeded to complete seven probe examinations of a healthy virtual hip joint. Eight targets were probed via the anterolateral portal. Task duration, number of collisions with soft tissue and bone, and distance travelled by arthroscope were measured by the simulator for every session. Results. A learning curve was demonstrated by the students, with significant improvements in time taken (P<0.01), number of collisions (P<0.01), collision severity (P<0.01), and efficiency of movement (P<0.01). The largest difference between consecutive sessions was seen between sessions 1 and 2, with sessions thereafter showing only minimal rates of improvement. Similar improvements were found in the probe examination with students showing significant improvements in time taken (P<0.01), number of collisions (P<0.01), collision severity (P<0.01) and distance travelled by arthroscope (P<0.01). Conclusion. The results of this study demonstrate a learning curve for a previously validated hip arthroscopy simulator, confirming improved performance with repeated use. These results support the use of virtual reality as a potential means of developing basic hip arthroscopic skills

To investigate the utility of virtual reality (VR) simulators in improving surgical proficiency in Orthopaedic trainees for complex procedures and techniques. Fifteen specialty surgeons attending a London Orthopaedic training course were randomised to either the VR (n = 7) or control group (n = 8). All participants were provided a study pack comprising an application manual and instructional video for the Trochanteric Femoral Nail Advanced (TFNA) procedure. The VR group underwent additional training for TFNA using the DePuy Synthes (Johnson and Johnson) VR simulator. All surgeons were then observed applying the TFNA in a Sawbones model and assessed by a blinded senior consultant using three metrics: time to completion, 22-item procedure checklist and 5-point global assessment scale. Participant demographics for the VR and control groups were similar in context of age (mean [SD]: VR group, 31.0 [2.38] years; control group, 30.6 [2.39] years), gender (VR group, 5 [71%] men; control group, 8 [100%] men) and prior experience with TFNA (had applied TFNA as primary surgeon: VR group, 6 [86%]; control group, 7 [88%]). Although statistical significance was not reached, the VR group, on average, outperformed the control group on all three metrics. They completed the TFNA procedure faster (mean [SD]: 18.2 [2.16] minutes versus 19.78 [1.32] minutes; p<0.189), performed a greater percentage of steps correctly (79% versus 66%; p<0.189) and scored a higher percentage on the global assessment scale (75% versus 65%; p<0.232). VR simulators offer a safe and accessible means for Orthopaedic trainees to prepare for and supplement their theatre-based experience. It is vital, therefore, to review and validate novel simulation-based systems and in turn facilitate their improvement. We intend to increase our sample size and expand this preliminary study through a second upcoming surgical course for Orthopaedic trainees in London

Introduction and Objective. Over the past few years, a reorganization of the educational pathways has been promoted with the purpose of optimizing the acquisition of competences and their assessment, so as to reduce the risks to both health care professionals and end users. Virtual reality (VR) has been repeatedly tested, initially as a positive reinforcement for more traditional educational pathways and, more recently, as their potential substitute. The aim of this study was to demonstrate the potentiality of VR simulation training in spine surgery. Materials and Methods. The VR simulator reproduced the lateral lumbar access to the spine. The simulation included a tutorial, the preoperative settings, and the surgical session with different levels of procedural complexity. A total of 10 users were recruited for this study: 3 senior surgeons (group A) and 7 orthopedic residents or junior orthopedic surgeons (group B). Each user completed the simulation twice. Results. The user's age or previous experience with VR technology did not show any relevance. On average, the entire simulation was completed in 24 minutes and 36 seconds. Group B showed an improvement between the 2 attempts in both sessions, the preoperative settings and the surgical simulation. The number of major errors dropped from an average of 5.2 to 1.8 and from an average of 4 (1–6) to 1.4, respectively. The simulation was never interrupted because of technical bugs or adverse effects related to the technology. Conclusions. VR-based training pathways might promote a high standard of care. Our preliminary experience suggests an effective implementation of the traditional coaching process

Introduction and Objective. Virtual Surgical Planning (VSP) is becoming an increasingly important means of improving skills acquisition, optimizing clinical outcomes, and promoting patient safety in orthopedics and traumatology. Pediatric Orthopedics (PO) often deals with the surgical treatment of congenital or acquired limbs and spine deformities during infancy. The objective is to restore function, improve aesthetics, and ensure proper residual growth of limbs and spine, using osteotomies, bone grafts, age-specific or custom-made hardware and implants. Materials and Methods. Three-dimensional (3D) digital models were generated from Computed Tomography (CT) scans, using free open-source software, and the surgery was planned and simulated starting from the 3D digital model. 3D printed sterilizable models were fabricated using a low-cost 3D printer, and animations of the operation were generated with the aim to accurately explain the operation to parents. All procedures were successfully planned using our VSP method and the 3D printed models were used during the operation, improving the understanding of the severely abnormal bony anatomy. Results. The surgery was precisely reproduced according to VSP and the deformities were successfully corrected in eight cases (3 genu varum in Blount disease, 2 coxa vara in pseudo achondroplasia, 1 SCFE, 1 missed Monteggia lesion and 1 post-traumatic forearm malunion deformity). In one case, a focal fibrocartilaginous dysplasia, the intraoperative intentional undersizing of the bone osteotomy produced an incomplete correction of a congenital forearm deformity. Conclusions. Our study describes the application of a safe, effective, user-friendly, VSP process in PO surgery. We are convinced that our study will stimulate the widespread adoption of this technological innovation in routine clinical practice for the treatment of rare congenital and post-traumatic limb deformities during childhood

We aim to explore the potential technologies for monitoring and assessment of patients undergoing arthroplasty by examining selected literature focusing on the technology currently available and reflecting on possible future development and application. The reviewed literature indicates a large variety of different hardware and software, widely available and used in a limited manner, to assess patients’ performance. There are extensive opportunities to enhance and integrate the systems which are already in existence to develop patient-specific pathways for rehabilitation.

Cite this article: Bone Joint J 2022;104-B(10):1104–1109.

In current practice in the UK there are three main approaches to investigating suspected scaphoid fractures not seen on initial plain film x-rays. Early MRI of all cases. Review all cases in clinic at two weeks with repeat x-rays. Hybrid model. Virtual Fracture Clinic (VFC) triage to reduce those who are seen in clinic at two weeks by:. ∘. Organising early MRI for those with high-risk presentation. ∘. Discharging those with an alternative more likely diagnosis. Our unit uses the VFC model. We aimed to evaluate its efficiency, safety, clinical outcomes and economic viability. All patients attending the emergency department with either a confirmed or suspected scaphoid fracture between March and December 2020 were included (n=305). Of these 297 were referred to the VFC: 33 had a confirmed fracture on x-ray and 264 had a suspected fracture. Of the suspected fractures reviewed in VFC 14% had an MRI organised directly owing to a high-risk presentation, 79% were brought for fracture clinic review and 17% discharged with an alternative diagnosis such as osteoarthritis. Of those subsequently reviewed in fracture clinic at two weeks: 9% were treated as scaphoid fractures (based on clinical suspicion and repeat x-rays), 17% had MRI or CT imaging organised, 5% did not attend and 69% were discharged. Overall, 17% of cases initially triaged, had further imaging – 41 MRIs and 5 CTs. MRI detected: 5% scaphoid fracture, 17% other fracture, 24% bone contusion, complete ligament tear 10%, partial ligament tear 39% and normal study 10%. The results of MRI minimally affected management. 3 patients were taken out of plaster early, 1 patient was immobilized who was not previously and no patients underwent operative management. In the following 12-month period one patient re-presented with a hand or wrist issue. This approach avoided 218 MRIs, equating to £24000 and 109 hours of scanner time. VFC triage and selective use of MRI scanning is a safe, efficient and cost-effective method for the management suspected scaphoid fractures. This can be implemented in units without the resource to MRI all suspected scaphoid fractures from the emergency department

Objectives. An optimal reconstruction of the joint anatomy and physiology during revision total knee replacement (RTKR) is technically demanding. The standard navigation systems were developed for primary procedures, and their adaptation to RTKR is difficult. We present a new navigation software dedicated to RTKR. The rationale of this new software was to allow a virtual planning of the joint reconstruction just after removal of the primary prosthesis. Methods. The new software was developed on the basis of a non-image based navigation system which has been extensively validated for implantation of a primary TKR. Following changes have been implemented: 1) to define and control the vertical level of the joint space on both tibia and femoral side; 2) to measure the tibio-femoral gaps independently in flexion et en extension on both medial and lateral tibio-femoral joints; 3) to virtually plan and control the vertical level and the orientation of the tibia component; 4) to virtually plan and control the sizing and the 3D positioning of the femoral component (figure 1); 5) to virtually plan and control the potential bone resection; 6) to virtually plan and control the potential bone defects and their reconstruction (bone graft or augments) (figure 2); 7) to virtually plan and control the size, the length and the orientation of the stems extensions independently on the femoral and on the tibia side (figure 3). The validity of the concept has been tested by 20 patients operated on for RTKR for any reason, with a routine reconstruction with a cemented, unconstrained revision implant. The accuracy of the experimental software was assessed 1) during the procedure after implantation of the RTKR by measuring the medial and lateral laxity in full extension and 90° of knee flexion with the navigation system, and 2) on post-operative radiographs. Results. No system failure was observed. The virtual planning of the reconstruction was possible in all cases. The intra-operative control of the different reconstruction steps was possible in all cases. The mean coronal tibio-femoral angle was 0+3°, and no outlier was observed. Coronal and sagittal orientation of the prosthetic components was considered satisfactory in all directions for 16 cases. The desired vertical level of the joint space was achieved in all cases. The desired patella height was achieved in 15 cases. The measurement of the knee laxity was satisfactory in 16 cases. A good bone-prosthesis contact was achieved in 17 cases for the tibia, but it was not possible to analyze accurately this criterion for the femur. Conclusion. The software used in the current study allowed performing a straightforward reconstruction of the knee joint anatomy and physiology during RTKR. The virtual planning prevented to perform repetitive trials with different technical solutions which are often necessary during conventional RTKR. The operating time may be consequently decreased

Aims. Arthroplasty skills need to be acquired safely during training, yet operative experience is increasingly hard to acquire by trainees. Virtual reality (VR) training using headsets and motion-tracked controllers can simulate complex open procedures in a fully immersive operating theatre. The present study aimed to determine if trainees trained using VR perform better than those using conventional preparation for performing total hip arthroplasty (THA). Patients and Methods. A total of 24 surgical trainees (seven female, 17 male; mean age 29 years (28 to 31)) volunteered to participate in this observer-blinded 1:1 randomized controlled trial. They had no prior experience of anterior approach THA. Of these 24 trainees, 12 completed a six-week VR training programme in a simulation laboratory, while the other 12 received only conventional preparatory materials for learning THA. All trainees then performed a cadaveric THA, assessed independently by two hip surgeons. The primary outcome was technical and non-technical surgical performance measured by a THA-specific procedure-based assessment (PBA). Secondary outcomes were step completion measured by a task-specific checklist, error in acetabular component orientation, and procedure duration. Results. VR-trained surgeons performed at a higher level than controls, with a median PBA of Level 3a (procedure performed with minimal guidance or intervention) versus Level 2a (guidance required for most/all of the procedure or part performed). VR-trained surgeons completed 33% more key steps than controls (mean 22 (. sd. 3) vs 12 (. sd. 3)), were 12° more accurate in component orientation (mean error 4° (. sd. 6°) vs 16° (. sd. 17°)), and were 18% faster (mean 42 minutes (. sd. 7) vs 51 minutes (. sd. 9)). Conclusion. Procedural knowledge and psychomotor skills for THA learned in VR were transferred to cadaveric performance. Basic preparatory materials had limited value for trainees learning a new technique. VR training advanced trainees further up the learning curve, enabling highly precise component orientation and more efficient surgery. VR could augment traditional surgical training to improve how surgeons learn complex open procedures. Cite this article: Bone Joint J 2019;101-B:1585–1592

Aims. Virtual fracture clinics (VFCs) are advocated by recent British Orthopaedic Association Standards for Trauma and Orthopaedics (BOASTs) to efficiently manage injuries during the COVID-19 pandemic. The primary aim of this national study is to assess the impact of these standards on patient satisfaction and clinical outcome amid the pandemic. The secondary aims are to determine the impact of the pandemic on the demographic details of injuries presenting to the VFC, and to compare outcomes and satisfaction when the BOAST guidelines were first introduced with a subsequent period when local practice would be familiar with these guidelines. Methods. This is a national cross-sectional cohort study comprising centres with VFC services across the UK. All consecutive adult patients assessed in VFC in a two-week period pre-lockdown (6 May 2019 to 19 May 2019) and in the same two-week period at the peak of the first lockdown (4 May 2020 to 17 May 2020), and a randomly selected sample during the ‘second wave’ (October 2020) will be eligible for the study. Data comprising local VFC practice, patient and injury characteristics, unplanned re-attendances, and complications will be collected by local investigators for all time periods. A telephone questionnaire will be used to determine patient satisfaction and patient-reported outcomes for patients who were discharged following VFC assessment without face-to-face consultation. Ethics and dissemination. The study results will identify changes in case-mix and numbers of patients managed through VFCs and whether this is safe and associated with patient satisfaction. These data will provide key information for future expert-led consensus on management of trauma injuries through the VFC. The protocol will be disseminated through conferences and peer-reviewed publication. This protocol has been reviewed by the South East Scotland Research Ethics Service and is classified as a multicentre audit. Cite this article: Bone Jt Open 2021;2(3):211–215

Background. Digital planning of implants in regard to position and size is done preoperatively in most cases. Intraoperative it can only be made by navigation systems. With the development of the VIPS-method (Virtual Implant Planning System) as an application for mobile C-arms, it is possible to do an intraoperative virtual planning of the screws near the joint in treatment of distal radius fractures by plating. Screw misplacement is a well known complication in the operative treatment of these fractures. The aim of this prospective randomised trial was to gain first clinical experiences and to compare VIPS with the conventional technique. The study hypothesis was that there will be less screw misplacement in the VIPS group. Methods. We included 40 patients with distal radius fractures type A3, C1 and C2 according to the AO-classification. In a pilot study the first 10 Patients were treated by the VIPS method to gain experience with VIPS in a clinical set-up. The results of the pilot-study are not part of this analysis. Then 15 Patients were web-based randomised into two groups. After diaphysial fixation of a 2.4 mm Variable Angle Two-Column Volar Distal Radius Plate and fracture reduction matching of a three-dimensional virtual plate to the two-dimensional image of the plate in the fluoroscopy shots in two plains was performed automatically in the VIPS group. The variable angle locking screws were planed in means of direction and length. Drilling was done by the use of the Universal Variable Angle Locking Drill Guide that was modified by laser marks at the rim of the cone to transfer the virtual planning. The drill guide enables drilling in a cone of 30°. In the control group the same implant was used in a conventional technique that means screw placement by the surgeon without digital planning. After implant placement an intraoperative three-dimensional scan was performed to check the position and length of the screws near the joint. OR- and fluoroscopy-time was documented. In addition the changes of misplaced screws were engaged. Results. In the VIPS group six A3-fractures, one C1-fracture and eight C2-fractures were included. In the control group six A3-fractures and nine C2-fractures were included. The intraoperative fluoroscopy time was 2.53 min (SD 1.44, range 1.27–7.14) in the VIPS group and 2.26 min (SD 0.51, range 1.55–3.39) in the control group (p=0.40). The OR-time was 53.33 min (SD 34.49, range 34–171) in the VIPS group and 42.27 min (SD 8.76, range 20–58) in the control group (p=0.23). In the VIPS group we changed three screws (two were too long, one was borderline near the joint) and two screws in the control group (one was too long, one was borderline near the joint) (p=0.24). Conclusions. The Virtual Implant Planning System is a reliable method that can be integrated easily in the workflow in treatment of distal radius fractures. There is a tendency that the virtual implant planning needs additional time, but there are no significant differences between the two groups. Further development is necessary to make the VIPS method beneficial

Introduction. An optimal reconstruction of the joint anatomy and physiology during revision total knee replacement (RTKR) is technically demanding. A new software was developed to allow a virtual planning of the joint reconstruction just after removal of the primary prosthesis. Material. Following changes have been implemented to the standard navigation software: 1) to define and control the vertical level of the joint space on both tibia and femoral side, and to allow performing the potential change decided prior to the revision procedure according to the preoperative imaging planning; 2) to measure the tibio-femoral gaps independently in flexion et en extension on both medial and lateral tibio-femoral joints; 3) to virtually plan and control the vertical level and the orientation of the tibia component; 4) to virtually plan and control the sizing and the 3D positioning of the femoral component; 5) to virtually plan and control the potential bone resection; 6) to virtually plan and control the potential bone defects and their reconstruction (bone graft or augments); 7) to virtually plan and control the size, the length and the orientation of the stems extensions independently on the femoral and on the tibia side. Methods. The validity of the concept has been tested by 20 patients operated on for RTKR for any reason, with a routine reconstruction with a cemented, unconstrained revision implant. The accuracy of the experimental software was assessed 1) during the procedure after implantation of the RTKR by measuring the medial and lateral laxity in full extension and 90° of knee flexion with the navigation system, and 2) on post-operative radiographs: coronal tibio-femoral angle, coronal and sagittal orientation of both tibia and femur components, vertical level of the reconstructed joint space, patella height, quality of the bone-prosthesis contact of both tibia and femur components. Results. No system failure was observed. The virtual planning of the reconstruction was possible in all cases. The intra-operative control of the different reconstruction steps was possible in all cases. The mean coronal tibio-femoral angle was 0+3°, and no outlier was observed. Coronal and sagittal orientation of the prosthetic components was considered satisfactory in all directions for 16 cases. The desired vertical level of the joint space was achieved in all cases. The desired patella height was achieved in 15 cases. The measurement of the knee laxity was satisfactory in 16 cases. A good bone-prosthesis contact was achieved in 17 cases for the tibia, but it was not possible to analyse accurately this criterion for the femur. Discussion. The software used in the current study allowed performing a straightforward reconstruction of the knee joint anatomy and physiology during RTKR. The virtual planning prevented to perform repetitive trials with different technical solutions which are often necessary during conventional RTKR. The operating time may be consequently decreased

Background. Embodiment- and distraction-based approaches to immersive virtual reality (IVR) show promise in treating persistent low back pain (PLBP). However, which approach is more effective is unclear. This study aims to evaluate the impact of distraction- and embodiment-based IVR on pain processing and patient-reported outcome measures in PLBP. Method. Individuals with PLBP were randomised to receive eight sessions of either distraction- or embodiment-based IVR over two weeks. Outcome measures were evaluated at baseline and after the eighth session. Pain processing was evaluated using conditioned pain modulation (CPM) and temporal summation (TS). Results. Three participants (n=2 embodiment, n=1 distraction) have completed all eight IVR sessions. Preliminary results indicate a decrease from pre to post-intervention in Numerical Pain Rating Scale score (pre: 5/10, 6/10, 5/10; post: 2/10, 5/10, 2/10) and Pain Catastrophising Scale score (pre: 34/52, 11/52, 38/52; post: 11/52, 8/52, 12/52), with no clear trend in other self-reported measures (Hospital Anxiety and Depression scale, Oswestry low back disability questionnaire, fear-avoidance beliefs questionnaire, Tampa scale of kinesiophobia). Preliminary results suggest a potential increase in NPRS absolute values from pre- to post-intervention in CPM (pre: -2.7, -2.3, -2.0; post: -3.3, -2.0, -4.3) and TS (pre-1.2, 2.5, 2.4; post: 1.4, 2.5, 3.1). Conclusion. Eight sessions of IVR may reduce pain severity and pain catastrophising in people with PLBP and may increase the efficacy of endogenous pain modulatory systems. Data collection is ongoing to compare the effect of distraction- and embodiment-based IVR. Conflicts of Interest. There are no conflicts of interest. Sources of Funding. This project is funded by the Saudi Arabia Cultural Bureau

Background. Virtual Reality (VR) uses headsets and motion-tracked controllers so surgeons can perform simulated total hip arthroplasty (THA) in a fully-immersive, interactive 3D operating theatre. The aim of this study was to investigate the effect of laboratory-based VR training on the ability of surgical trainees to perform direct anterior approach THA on cadavers. Methods. Eighteen surgical trainees (CT1-ST4) with no prior experience of direct anterior approach (DAA) THA completed an intensive 1-day course (lectures, dry-bone workshops and technique demonstrations). They were randomised to either a 5-week protocol of VR simulator training or conventional preparation (operation manuals and observation of real surgery). Trainees performed DAA-THA on cadaveric hips, assisted by a passive scrub nurse and surgical assistant. Performance was measured on the Intercollegiate Surgical Curriculum Project (ISCP) procedure-based assessment (PBA), on a 9-point global summary score (Table 1). This was independently assessed by 2 hip surgeons blinded to group allocation. The secondary outcome measure was error in cup orientation from a predefined target (40° inclination and 20° anteversion). Results. Surgeons trained using VR performed a cadaveric DAA-THA significantly better than those using conventional preparation, as assessed by acetabular cup orientation (p<0.001) and using the ISCP-PBA. Two VR surgeons achieved Level 3b, 6 were graded at Level 3a, and 1 was graded at Level 2b. Six non-VR surgeons achieved Level 2a and 3 were graded at Level 1b. Discussion. These data demonstrate transfer of procedural knowledge and psychomotor skills learnt from VR to a real-world setting. Conventional preparation had limited value for novice surgeons learning arthroplasty. VR training advanced them further up the learning curve. Implications. Virtual reality can augment surgical training for open procedures in orthopaedics curve, so opportunities in real surgery can be maximised. This has implications for how surgical training is delivered for surgeons learning a new, complex procedure. For any figures or tables, please contact the authors directly

Evidence supporting the use of virtual reality (VR) training in orthopaedic procedures is rapidly growing. However, the impact of the timing of delivery of this training is yet to be tested. We aimed to investigate whether spaced VR training is more effective than massed VR training. 24 medical students with no hip arthroplasty experience were randomised to learning the direct anterior approach total hip arthroplasty using the same VR simulation, training either once-weekly or once-daily for four sessions. Participants underwent a baseline physical world assessment on a saw bone pelvis. The VR program recorded procedural errors, time, assistive prompts required and hand path length across four sessions. The VR and physical world assessments were repeated at one-week, one-month, and 3 months after the last training session. Baseline characteristics between the groups were comparable (p > 0.05). The daily group demonstrated faster skills acquisition, reducing the median ± IQR number of procedural errors from 68 ± 67.05 (session one) to 7 ± 9.75 (session four), compared to the weekly group's improvement from 63 ± 27 (session one) to 13 ± 15.75 (session four), p < 0.001. The weekly group error count plateaued remaining at 14 ± 6.75 at one-week, 16.50 ± 16.25 at one-month and 26.45 ± 22 at 3-months, p < 0.05. However, the daily group showed poorer retention with error counts rising to 16 ± 12.25 at one-week, 17.50 ± 23 at one-month and 41.45 ± 26 at 3-months, p<0.01. A similar effect was noted for the number of assistive prompts required, procedural time and hand path length. In the real-world assessment, both groups significantly improved their acetabular component positioning accuracy, and these improvements were equally maintained (p<0.01). Daily VR training facilitates faster skills acquisition; however weekly practice has superior skills retention

Introduction. The efficacy of Virtual Reality (VR) as a teaching augment for arthroplasty has not been well examined for unfamiliar multistep procedures such as unicompartmental knee arthroplasty (UKA). This study sought to determine if VR improves surgical competence over traditional procedural preparation when performing a UKA. Methods. 22 Orthopaedic trainees were randomized to training sessions: 1) “VR group” with access to an immersive VR learning module that had been designed in conjunction with the manufacturer or 2) “Guide group” with access to manufacture's technique guide and surgical video. Both groups then performed a full UKA on SawBones models. Surgical competence was assessed via Objective Structures Assessment of Technical Skills (OSATS) validated rating system (max 25 points). Results. Participants equally distributed all training levels between groups. There was no difference in surgical times between VR and Guide groups (VR=43.0 vs Guide=42.4 mins; p=0.9). There was no difference in total OSATS score between groups (VR=14.2 vs Guide=15.7; p=0.59). There was also no difference between groups when sub-analysis was performed by training level. Most felt VR would be a useful tool for resident education (77%) and reported a likeliness to utilize VR for case preparation if available (86.4%). Conclusion. In a randomized controlled trial for trainees performing a complex, unfamiliar procedure (UKA), VR training demonstrated equivalent surgical competence to traditional technique guides and videos. Despite this, the majority of trainees find the technology beneficial and would use it if available. This project suggests as currently constructed, VR should be incorporated as an adjunct, rather than a replacement, to traditional surgical preparation/training methods

Abstract. Objectives. Evidence supporting the use of immersive virtual reality (iVR) training in orthopaedic procedures is rapidly growing. However, the impact of the timing of delivery of this training is yet to be tested. This study investigated whether spaced iVR training is more effective than massed iVR training for novices learning hip arthroplasty. Methods. 24 medical students with no hip arthroplasty experience were randomised to learning total hip arthroplasty using the same iVR simulation training either once-weekly or once-daily for four sessions. Participants underwent a baseline physical world assessment to orientate an acetabular component on a saw bone pelvis, and a baseline knowledge test. In iVR, we recorded procedural errors, time, numbers of prompts required and path lengths of the hands and head across 4 sessions. To assess skill retention, the iVR and baseline physical world assessments were repeated at one-week and one-month. Results. Baseline characteristics between the groups were comparable (p > 0.05). The daily group demonstrated faster skills acquisition, reducing the mean number of procedural errors from 76.8±37.5 (S1) to 11.1±10.1 (S4), compared to the weekly group improvement from 71.1±19.1 (S1) to 17.2±10.6 (S4), p < 0.001. The weekly group error count plateaued remaining at 16±6.7 at 1-week and 17.5±8.5 at one-month, the daily group however, showed poor retention with error counts rising to 17.8±10.5 at 1 week and becoming higher than the weekly group at one-month to (23.2±13.0 vs 17.5±10.5). A similar effect was noted for procedural time and the number of assistive prompts. In the real-world assessment, both groups significantly improved the accuracy of their acetabular component positioning, these improvements were equally maintained. Conclusions. Daily iVR training facilitates faster skills acquisition, however weekly practice has superior skills retention. Skills learnt using both regimes demonstrate sustained transfer to the real-world

Simulation is an effective adjunct to the traditional surgical curriculum, though access to these technologies is often limited and costly. The objectives of this work were to develop a freely accessible virtual pedicle screw simulator and to improve the clinical authenticity of the simulator through integration of low-cost motion tracking. The open-source medical imaging and visualisation software, 3D Slicer, was used as the development platform for the virtual simulation. 3D Slicer contains many features for quickly rendering and transforming 3D models of the bony spine anatomy from patient-specific CT scans. A step-wise pedicle screw insertion workflow module was developed which emulated typical pre-operative planning steps. This included taking anatomic measurements, identifying insertion landmarks, and choosing appropriate screw sizes. Monitoring of the surgeon's simulated tool was assessed with a low-cost motion tracking sensor in real-time. This allowed for the surgeon's physical motions to be tracked as they defined the virtual screw's insertion point and trajectory on the rendered anatomy. Screw insertion was evaluated based on bone density contact and cortical breaches. Initial surgeon feedback of the virtual simulator with integrated motion tracking was positive, with no noticeable lag and high accuracy between the real-world and virtual environments. The software yields high fidelity 3D visualisation of the complex geometry and the tracking enabled coordination of motion to small changes in both translational and angular positioning. Future work will evaluate the benefit of this simulation platform with use over the course of resident spine rotations to improve planning and surgical competency

Osteotomies around the knee are traditionally templated on 2D plain X-rays. Results are often inaccurate and inconsistent and multiplanar osteotomies are hard to perform. The aim of this study is to evaluate the feasibility and accuracy of virtual three-dimensional CT-based planning and correct execution of osteotomies around the knee with the aid of patient specific surgical guides and locking plates. Eight consecutive patients with significant malalignment of the lower limb were included in the study. Pre-operative CT scans of the affected limb and the normal contra-lateral side were obtained and 3D models of the patient's anatomy were created, using dedicated software. The healthy contralateral limb was mirrored and geometrically matched to the distal femur or proximal tibia of the healthy side. A virtual opening wedge correction of the affected bone was used to match the geometry of the healthy contralateral bone. Standard lower limb axes measurements confirmed correction of the alignment. Based on the virtual plan, surgical guides were designed to perform the planar osteotomy and achieve the planned wedge opening and hinge axis orientation. The osteotomy was fixed with locking plates and screws. Post-operative assessment included planar X-rays, CT-scan and full leg standing X-rays. One three-planar, three bi-planar and four single-plane osteotomies were performed. Maximum weightbearing mechanical femoro-tibial coronal malalignment varied between 7° varus and 14° valgus (mean 7.6°, SD 3.1). Corrective angles varied from 7°–15° (coronal), 0°–13° (sagittal) and 0°–23° (horizontal). The maximum deviation between the planned pre-operative wedge angle and the executed post-operative wedge angle was 1° in the coronal, sagittal and horizontal plane. The desired mechanical femorotibial axis on full-leg standing X-rays was achieved in 6 patients. Two patients were undercorrected by 1° and 2° respectively. Conclusion. 3D planning and guided correction of multi-planar deformity of femur or tibia is a feasible and accurate novel technique

Purpose. A Virtual Spinal Clinic (VSC) was set-up at a regional spinal referral centre to see if patient care could be improved through early advice to provide timely management, early onward referral, improve patient satisfaction and minimise chronicity. The clinic was based on the successful virtual model used throughout the country within orthopaedic fracture clinics. VSC is a Consultant led multi-disciplinary (MDT) clinic run by Advanced Practitioners (AP). Methods. A 3-month trial of the VSC was completed bi-weekly. Patients diagnosed with conservatively managed spinal fractures were referred from the on-call service. A management plan was devised by a Consultant Spinal Surgeon and communicated to patients by the AP via a telephone-call consultation where clinical advice and management could be discussed. Results. 23 clinics completed. 271 patient contacts. 216 reviewed virtually. Completed outcomes of VSC. 34.65% Discharged. 51.18% Routine appointment. 14.17% Urgent appointment. Conclusion. VSC successfully completed safe and timely assessments, management plans, telephone consultations and onward referrals for Greater Manchester patients with acute spinal fractures. Patients had earlier access to health professionals to provide advice, reassurance, complete onward referrals and safety-netting. Patient satisfaction improved, with patient reporting the telephone consultation was reassuring and allowed early return to previous function. VSC reduced patients waiting time for a follow-up appointment and reduced patients travel time across Greater Manchester. In the future, it is hoped that the 6-week follow-up telephone call service will be utilised more as VSC develops. No conflicts of interest. No funding obtained

Hip arthroscopy is a rapidly expanding technique that has a steep learning curve. Simulation may have a role in helping trainees overcome this. However there is as yet no validated hip arthroscopy simulator. This study aimed to test the construct validity of a virtual reality hip arthroscopy simulator. Nineteen orthopaedic surgeons performed a simulated arthroscopic examination of a healthy hip joint in the supine position. Surgeons were categorized as either expert (those who had performed 250 hip arthroscopies or more) or novice (those who had performed fewer than this). Twenty-one targets were visualized within joint; nine via the anterior portal, nine via the anterolateral and three via the posterolateral. This was followed by a task testing basic probe examination of the joint in which a series of eight targets were probed via the anterolateral portal. Each surgeon's performance was evaluated by the simulator using a set of pre-defined metrics including task duration, number of soft tissue & bone collisions, and distance travelled by instruments. No repeat attempts at the tasks were permitted. Construct validity was then evaluated by comparing novice and expert group performance metrics over the two tasks using the Mann–Whitney test, with a p value of less than 0.05 considered significant. On the visualization task, the expert group outperformed the novice group on time taken (P=0.0003), number of collisions with soft tissue (P=0.001), number of collisions with bone (P=0.002) and distance travelled by the arthroscope (P=0.02). On the probe examination, the two groups differed only in the time taken to complete the task (P=0.025). Increased experience in hip arthroscopy was reflected by significantly better performance on the VR simulator across two tasks, supporting its construct validity. This study validates a virtual reality hip arthroscopy simulator and supports its potential for developing basic arthroscopic skills

The kinematic and kinetic characteristics of the knee after TKR are known to be strongly influenced by the alignment and positioning of the implanted components. In this paper we apply a virtual multi-fiber ligament model to a rigid body model of the post-surgical knee to explore how variations in alignment and positioning affect the predicted behavior of the ligaments and contact forces. We vary the angular and translational positioning of the femoral and tibial TKR components relative to the bone. Meanwhile the proximal and distal insertion sites of the ligaments are held constant relative to the bony structures. We evaluate sensitivity of the ligament balance and peak ligament tension through the passive flexion arc in response to the variation in positioning and alignment of the TKR components. With further development, this work holds the promise of applications in surgical planning and virtual arthroplasty

Background. Revision total knee arthroplasty (rTKA) is a high stakes procedure with complex equipment and multiple steps. For rTKA using the ATTUNE system revising femoral and tibial components with sleeves and stems, there are over 240 pieces of equipment that require correct assembly at the appropriate time. Due to changing teams, work rotas, and the infrequency of rTKR, scrub nurses may encounter these operations infrequently and often rely heavily on company representatives to guide them. In turn, this delays and interrupts surgical efficiency and can result in error. This study investigates the impact of a fully immersive virtual reality (VR) curriculum on training scrub nurses in technical skills and knowledge of performing a complex rTKA, to improve efficiency and reduce error. Method. Ten orthopaedic scrub nurses were recruited and trained in four VR sessions over a 4-week period. Each VR session involved a guided mode, where participants were taught the steps of rTKA surgery by the simulator in a simulated operating theatre. The latter 3 sessions involved a guided mode followed by an unguided VR assessment. Outcome measures in the unguided assessment were related to procedural sequence, duration of surgery and efficiency of movement. Transfer of skills was assessed during a pre-training and post-training assessment, where participants completed multi-step instrument selection and assembly using the real equipment. A pre and post-training questionnaire assessed the participants knowledge, confidence and anxiety. Results. All participants reported orthopaedics as their primary speciality with mean of 6-years experience. 80% reported they are ‘sometimes’ required to scrub for operations in which they do not feel comfortable with the equipment. All participants improved across the 3 unguided sessions reducing their operative time by 47%, assistive prompts by 75%, dominant hand motion by 28% and head motion by 36%. This transferred into the real-world: Participants completed 11.3% of tasks correctly in pre-training compared to 83.5% correct in the timely selection and assembly of rTKA equipment, post-training. All participants reported increased confidence and reduced anxiety after the training. Conclusion. Unfamiliarity with orthopaedic procedures or equipment is common for scrub nurses and can impact surgical performance. VR training improves their understanding, technical skills and efficiency in complex rTKA. These VR-learnt skills translate into the physical environment. This has important implications on how scrub nurses can be trained remotely, asynchronously and safely to perform complex orthopaedic surgery

Cannulated screw fixation is currently the treatment of choice for slipped capital femoral epiphyses (SCFE). A SCFE module of the Bonedoc simulator was created in order to test the ability of advanced trainees to place the screw in the correct position, and the practicality of using the simulator within the orthopaedic surgery training curriculum. Bonedoc (University of Auckland) is a virtual reality simulator of image guided orthopaedic operations. 1. This simulator runs in Internet Explorer (Microsoft, USA) using the Octaga (Octaga, Norway) plugin. The total download is around 4 MB. The SCFE module was created from a CT scan of a Grade 2 acute on chronic SCFE. DICOM images were imported into 3DView (. www.rmrsystems.co.uk. ) and a mesh created. The generic femur from the DHS module was morphed within the CAD package Blender (Blender.org) to conform to this reconstructed SCFE mesh. Forty two advanced trainees operated on the same virtual SCFE during a training weekend. The trainees had 25 minutes to become familiar with the simulator and complete the operative case. The trainees performed all tasks relevant to the operation. At the operation’s conclusion the trainees self-assessed their performance. Subsequently the simulator provided surgically relevant objective feedback on aspects such as exact position of the screw, misplaced attempts and the number of x-rays. The results were analysed using SAS (SAS Institute, USA) in subgroups based on year on the scheme, as well as correlated within each operation. There was no difference in the accuracy with which the virtual slipped capital femoral epiphysis was pinned by trainees in different years in the training programme. However, 26 of the 39 of the virtual screws were placed in the superior direction. There was no correlation between number of X-ray images taken and final accuracy of screw placement. The number of misplaced drill holes was correlated both with number of X-ray images taken (p< 0.01) and operative time (p< 0.01) but not with final accuracy of the screw. An increase in misplaced attempts was correlated with angulation errors in the anterior plane (p< 0.01). There was no correlation between the trainees’ self assessment and any of the measured variables. The Bonedoc simulator provides a means to test trainees on technical aspects of a surgical procedure. It provides objective results, which can mimic real world outcomes. In addition, the ability to test all trainees on the same virtual operative case allows standardisation of assessment. All trainees completed the task to a similar level of accuracy, which may reflect the overall skill level in advanced trainees within the New Zealand. However, many trainees placed the screw in the superior portion of the femoral head, which is thought to increase the risk of avascular necrosis. 2. Further work is required to evaluate how accurately performance on the simulator predicts performance in the operating theatre

Micro level finite element models of bone have been extensively used in the literature to examine its mechanical behaviour and response to loads. Techniques used previously to create these models involved CT attenuations or images (e.g. micro-CT, MRI) of real bone samples. The computational models created using these methods could only represent the samples used in their construction and any possible variations due to factors such as anatomical site, sex, age or degree of osteopo-rosity cannot be included without additional sample collection and processing. This study considers the creation of virtual finite element models of trabecular bone, i.e. models that look like and mechanically behave like real trabecular bone, but are generated computationally. The trabecular bone is anisotropic both in terms of its micro-architecture and its mechanical properties. Considerable research shows that the key determinants of the mechanical properties of bone are related to its micro-architecture. Previous studies have correlated the apparent level mechanical properties with bone mineral density (BMD), which has also been the principal means of diagnosis of osteoporosis. However, BMD alone is not sufficient to describe bone micro-architecture or its mechanical behaviour. This study uses a novel approach that employs BMD in conjunction with micro-architectural indices such as trabecular thickness, trabecular spacing and degree of anisotropy, to generate virtual micro-architectural finite element models. The approach permits generation of several models, with suitable porous structure, for the same or different levels of osteoporosity. A series of compression and shear tests are conducted, numerically, to evaluate the apparent level orthotropic elastic properties. These tests show that models generated using identical micro-architectural parameters have similar apparent level properties, thus validating this initial bone modelling algorithm. Numerical tests also clearly illustrate that poor trabecular connectivity leads to inferior mechanical behaviour even in cases where the BMD values are relatively high. The generated virtual models have a range of applications such as understanding the fracture behaviour of osteoporotic bone and examining the interaction between bone and implants

The palpation of the controlateral iliac spinae remains a major hurdle to the success of navigation in lateral position. Several studies are seeking for alternative landmarks to compute the anterior pelvic plane (APP). Up to now, none of those methods have been used in clinical routine. Ultrasound navigation offers a great potential to identify new bony landmarks. The tubercles of the lower lumbar spine and the symphysis can easily be imaged. Those points define a sagittal plane, that can be used as a symmetry plane to compute a virtual controlateral spinae from the acquired colateral spinae. A virtual pelvic plane can then be computed. The objective of this study was to check the accuracy and reproducibility of this virtual anterior pelvic plane. 6 hips (3 left, 3 right) from 4 cadavers (mean BMI 22,6; range 19,5–26,7) embalmed with glycerol and alcohol were used for this study. All anatomic landmarks were acquired with the OrthoPilot® Ultrasound navigation system. One experienced surgeon acquired the reference APP with the cadavers lying supine. The cadavers were then placed in lateral position. Two experienced surgeons acquired 6 times following landmarks: 3 lower lumbar tubercles, 3 sacral tubercles (see Figure 1), the posterior spines, the symphysis and the colateral iliac spine. Several sagittal planes were computed using all points (least square plane) and all possible combinations between one symphysis point, one lower lumbar tubercle point (L5, L4 or L3), and one sacral tubercle point (S2 or S1). The angular error of the resulting virtual APP to the reference APP was computed. For each cadaver, an error map was computed to visualize the error of the virtual APP with respect to the height of the used sacral and lumbar tubercles along the spine. The reference APP was acquired with a good reproducibility: the deviation between each acquisition to the mean of all acquisitions was smaller than 1° (except for cadaver 2 right side, the deviation reached 2 ° in the frontal plane). As some sacral and lumbar points were mixed during the acquisition, the line joining the posterior spines was used to separate the sacral from the lumbar points. The mean errors and standard deviations were comparable between operators. The least square plane computed with all points strongly depended on the cadaver positioning : for the same cadaver, the mean error reached 0°on the left side and 8° on the right side. More constant results were obtained by using a combination of 3 points. 5 outliers were identified and removed as they clearly corresponded to erroneous acquisitions on bad quality images. After having removed those outliers, the mean error ranged between 2° and 5° and the standard deviation between 1° and 3°. The best combination of points was a point on the symphysis, the lowest sacral tubercle (S2) and the lowest lumbar tubercle (L5). This study shows that the symphysis, the lower lumbar and sacral tubercles can be used to define a sagittal plane and thereby define a virtual anterior pelvic plane. Outliers should be suppressed by taking special care to the image quality and by adding a guided ultrasound functionality: visualizing the resulting sagittal plane on the ultrasound picture would enable the surgeon to easily control the accuracy of his acquired plane. The next steps consist in checking the feasibility in a clinical set-up

Introduction. Fixation has been shown to be the primary indicator of an implant's long-term success. Failure to achieve attachment, especially in acetabular and TKR, has been attributed to a lack of initial stability and gaps between the implant and bone. Gaps greater than 150 microns allow fibrous tissue to form. Properly addressing implant design features can help avoid adverse outcomes. ASTM International Standards (F1854-09) do not assess the relationship between porosity of the coating and that of cancellous bone, which can lead to an absence of mechanical interlock. This study developed a virtual program that uses human cancellous bone to predict potential skeletal attachment for implants properly placed for TJR. The goal of the Virtual Paradigm was to assess initial contact surface area at the time of implantation. Methods. Seven human femurs and tibias were used. Bones from 11 males and 3 females were used, ages ranging from 40 to 61. Five porous coatings were assessed: Biofoam (Wright Medical), Fiber Mesh, CSTI, Tantalum (Zimmer), and P² (DJO Global). Specimen Processing. Each bone was resected 2 mm beyond the articulating surface into the cancellous host using surgical TKA instruments. The specimens and coatings were embedded in PMMA. For Part 1, the specimens and coatings were cut perpendicular to the neutral axis, displaying a surface view for scanning electron microscopy (SEM). For Part 2, the coatings were cross-sectioned for SEM, ground, and polished to optical finish. Imaging: Part 1. The bone and coating sections displaying the surface view were imaged using SEM under backscatter (BSE) at 22x. Three images were taken of each tibia section, resulting in 12 images. Three images were taken of each femur section, resulting in 9 images. Analysis: Part 1. Each bone image was overlaid onto each coating image. Using various computer programs (IQ Materials, Fastone Image Viewer, Corel Photopaint X3), available bone was normalized to 100% and bone-implant contact was marked red (Figure 1). Imaging: Part 2. The cross-sectioned coatings were imaged with SEM-BSE at 30x. For each implant, 3 images were taken and assembled together (Microsoft Research ICE). Analysis: Part 2. Using the programs, bone images were overlaid onto each coating to establish a 200-micron region of initial contact. The surface of the coating within this region was calculated to represent surface roughness (Figure 2). Results. Bone porosity ranged from 14.04%-23.04% in the femur and 11.85%-23.68% in the tibia. Percent contact between the implant and bone ranged from 3.28%-43.47% (Figure 1). Surface roughness ranged from 5.4–11.1 mm (Figure 2). Opening porosity of the coatings ranged from 52.54%-94.97% (Figure 3). Discussion. Long-term success of cementless TJR depends on mechanical stability and bone attachment. This virtual study addressed fixation and contact between coatings and cancellous bone, and it can be used to evaluate innovative materials intended for TJR. This program challenged the limits of ASTM Standards for screening coatings. The results of this study demonstrated that the Virtual Bone-Implant Surface Contact Paradigm could be used in the early phases of implant development and testing to assess clinical success

Introduction. Osteotomies around the knee are traditionally templated on 2D plain X-rays. Results are often inaccurate and inconsistent and multiplanar ostetomies are hard to perform. The aim of this study is to evaluate the feasibility and accuracy of virtual three-dimensional CT-based planning and correct execution of osteotomies around the knee with the aid of patient specific surgical guides and locking plates. Methods. Eight consecutive patients with significant malalignment of the lower limb were included in the study. Pre-operative CT scans of the affected limb and the normal contra-lateral side were obtained and 3D models of the patient's anatomy were created, using dedicated software. The healthy contralateral limb was mirrored and geometrically matched to the distal femur or proximal tibia of the healthy side. A virtual opening wedge correction of the affected bone was used to match the geometry of the healthy contralateral bone. Standard lower limb axes measurements confirmed correction of the alignment. Based on the virtual plan, surgical guides were designed to perform the planar osteotomy and achieve the planned wedge opening and hinge axis orientation. The osteotomy was fixed with locking plates and screws. Post-operative assessment included planar X-rays, CT-scan and full leg standing X-rays. Results. One three-planar, three bi-planar and four single-plane osteotomies were performed. Maximum weightbearing mechanical femoro-tibial coronal malalignment varied between 7° varus and 14° valgus (mean 7.6°, SD 3.1). Corrective angles varied from 7°-15°(coronal), 0°–13°(sagittal) and 0°–23°(horizontal). The maximum deviation between the planned pre-operative wedge angle and the executed post-operative wedge angle was 1° in the coronal, sagittal and horizontal plane. The desired mechanical femorotibial axis on full-leg standing X-rays was achieved in 6 patients. Two patients were undercorrected by 1° and 2° respectively. Conclusion. 3D planning and guided correction of multi-planar deformity of femur or tibia is a feasible and accurate novel technique

Purpose: Surgical trainees develop psychomotor skills using various techniques, with simulators providing safe practicing environments. There has been no development of virtual simulators with haptics (force feedback) that allow residents to practice the open surgical fixation of common orthopedic fractures. The main purpose of this study was to assess if residents performed similarly on a newly developed virtual simulator as on a Sawbones simulator using a modified checklist and global rating scale. Secondary purposes were to assess the reliability and validity of these procedural measurement tools. Method: A stratified randomized within-subjects study was performed with 22 surgical trainee volunteers. They were randomized to first perform surgical fixation of the ulna using either the virtual or Sawbones simulator, and then performed the same procedure on the other simulator. Evaluators completed a task-specific checklist, global rating scale (GRS), total error score and time to completion for each participant on both simulators. Results: The participants achieved significantly better scores on the virtual simulator compared to the Sawbones simulator (p0.8), except in time to completion. When combined, the checklist and GRS maintained high levels of internal consistency (Cronbach’s a > 0.80) and inter-rater reliability (intraclass coefficient > 0.90) for both simulators. A Pearson’s product moment correlation was used to demonstrate criterion validity of the measurement tools. They were all significantly correlated to each other within simulators (p0.9), while the virtual simulator achieved construct validity for the GRS and total error score (p1.1). Conclusion: The modified procedural measurement tools demonstrate reliability and validity and the virtual simulator shows evidence of construct validity. These tools were used to evaluate participants, demonstrating the achievement of better scores on the virtual simulator compared to the Sawbones simulator. The only concern at this time is that the procedural measurement tool scores do not correlate between simulators. The newly developed virtual ulna surgical fixation simulator with haptics shows promise for helping surgical trainees learn and practice basic skills, but requires further modifications before it can attain the same standards as the current gold standard simulators

Background. The distal part of the radius is the most common localisation of fractures of the human body. Dislocated intraarticular fractures of the distal radius (FDR) are frequently treated by open reduction and internal fixation with a volar locking plate (VLP) under fluoroscopic guidance. Typically the locking screws are placed subchondral near the joint line to achieve maximum stability of the osteosynthesis. To avoid intraarticular screw placement an intraoperative virtual implant planning system (VIPS) as an application for mobile C-arms was established. The aim of the study was the validation of the implemented VIPS comparing the intraoperative planning with the actual placement of the screws. The study was conducted as a single-centre randomised controlled trial in a primary care institution. The hypothesis of the study was that there is conformity between the virtual implant position and the real implant placement. Patients/Material and Methods. 30 patients with FDR type A3, C1 and C2 according to the AO-classification were randomised in two treatment groups and allocated either in the conventional or in the VIPS group in which the patients underwent an intraoperative planning before screw placement. The randomisation was performed on the basis of a computer-generated code. After fracture reduction an initial diaphyseal fixation of the plate was done. Then the matching of the three-dimensional virtual plate with the image of the real plate in the fluoroscopy shots in two planes was performed automatically. The implant placement was planned intraoperatively in terms of orientation, angulation and length of the screws. After the placement of four or five locking screws the implant position was verified with an intraoperative three-dimensional mobile C-arm scan. The locking screws near the joint line were examined and compared in relation to the actual and the planned inclination angle, the azimuth angle which is determined analogue to a compass rose and the screw-tip distance. The planned and actual parameters of the locking screws were then statistically analysed applying the Shapiro-Wilk - and the Students t-test. Results. 15 patients with FDR were treated in the VIPS arm. In the VIPS group six fractures type A3 one type C1 and eight type C2 were included. The control group showed a similar fracture distribution with six type A3 and nine type C2 fractures. The discrepancy between the actual and the planned screw-tip distance was 2,24 ± 0,97 mm and did not differ significantly (p>0,05). The angle of the planned and actual screw placement also did not vary significantly (p>0,05). The difference of the actual to the planned azimut angle accounted for 18,69°± 29,84. The planned and real inclination of the screws differed by 1,66° ± 4,46. Conclusion. The analysis shows that the screws were almost placed as planned. Differences between actual and planned placement of the screws were observed but were not statistically significant. Therefore the hypothesis of the study can be accepted. We assume, that the precise planning of the screw placement in FDR with VIPS can be transported into the surgical treatment

Virtual Fracture Clinic (VFC) is a consultant-led orthopaedic trauma outpatient triage and management service. The use of VFC has recently become commonplace in the United Kingdom. It allows multiple referral sources to the orthopaedic team, with clinical information and imaging reviewed by a consultant in VFC who formulates an appropriate management plan with the patient contacted; either to attend clinic for consultation or discharged with advice over the phone. The VFC is more efficient than a traditionally delivered outpatient fracture clinic service. We have utilized VFC for 1 year at our hospital, East Kent University Hospital Foundation Trust (EKHUFT), and undertook a closed loop audit to evaluate the service and highlight potential areas of improvement. The Objective of the study was to identify whether the implementation of new re-designed VFC referral guidelines together with teaching set across one of the hospitals in EKHUFT improved the effectiveness and standards of VFC referrals. An initial audit was performed of all referrals made to VFC over a 2 weeks period in December 2018. Changes to the VFC referral pathway were implemented, and teaching sessions performed by the orthopaedic team to all referring units, including minor injury units (MIU) and the emergency department (ED). After implementation, re-audit of VFC referrals was performed in February 2019 over a similar 2 weeks period. Patient demographics, diagnosis and outcomes were collected from the online patient record with images reviewed using PACS software. Following intervention, referral rates dropped by 27.7% (136 vs 188 patients) over the 2 weeks periods. Patient demographics, injury type and severity remained the same between the 2 groups. 51.5% (70/136) did not meet VFC pathway criteria after the intervention and were considered inappropriate, compared to 70% in the original group. 15.4% (21/136) referrals could have been managed in the emergency department using the new guidelines and leaflet discharge. 5.1% (7/136) of the referrals should have been referred to orthopaedic on-call acutely and 22% (30/136) of the referrals had a soft tissue injury or no injury identified. This did not change between the 2 groups despite intervention. Referring MIU and ED units require continued support and teaching over a prolonged time period to hopefully see further improvements. Immediate hot reporting of radiographs may further benefit the service, but staffing and funding issues particularly out of hours, means this remains an aspiration

Purpose: Posters of study: To produce a virtual reality model of prosthetic knee joint motion, giving detail regarding contact area and contact pressures during the process of walking. Method: Using serial CT scans and data regarding the material properties of bone, cartilage, ligaments and other soft tissue structures a computational “virtual reality model” of the knee has been constructed. This computational model which is a 3D dynamic representation of a human knee joint, may be programmed to replicate the standard gait pattern of the human knee. This study details the development of this model and its validation against the accepted Stenmore Test Rig for modelling of knee joint movement and knee prosthetic wear. The validation results will be presented,. The model allows the calculation and representation of contact pressures and contact areas in the knee joint as it moves through the gait cycle. This study also shows the effect of uni-condular loading and varus mal-positioning which may occur at surgery and the effect this has on the contact area and contact pressures of a prosthetic knee in ambulation. The resultant gait pattern produced by uni-condular loading and exhibited by the virtual knee closely resembles that seen in In Vivo Kinematic Studies reported by other authors. In conclusion we present this as a valid computational dynamic model of knee prosthetic wear and kinematics which represents an enormous advantage over standard mechanical testing and presents possibilities for rapid analysis in new knee joint designs and the effect of abnormalities of gait and wear

Introduction. Three-dimensional preoperative planning and bone tumour resection by navigation have been used in the past ten years. According to literature this workflow increases the surgical “accuracy”. However, there are a few and not completely clear reports describing accuracy in preoperative planning and navigation. The objective of this preliminary study was to determine the accuracy of osteotomies planned and guided by navigation in pelvis tumour resection. We assume that the surgical specimen scanned and 3D reconstructed is an acceptable method to determine the accuracy qualitatively and quantitatively of a virtual planning and navigation surgical workflow. Materials and Methods. A total of four patients were evaluated between May 2010 and February 2011, age range: 6–38, 17.4 mean; 2 males and 2 females. There were 4 malignant tumours: Malignant Schwannoma (1), Ewing's tumor (1) and Chondrosarcoma (2). All anatomic regions compromised by the tumour were preoperatively CT scanned (Mutislice 64, Aquilion, Toshiba Medical Systems, Otawara, Japan). Magnetic resonance images (MRI) of the corresponding region were acquired using a 1.5-T unit (Magnetom Avanto, Siemens Medical Solutions, Erlangen, Germany). Image fusion was applied to CT and MRI studies in order to determine the bone cortex and the intra-extraosseous soft tissues tumour extension. Once the fusion was obtained osteotomies were planned, taking into account the tumour extension in a three-dimensional virtual scenario. All patients were planned for two uniplanar osteotomies (intercalary resection). The minimal margin was determined in each plane by measuring the closest distance between malignant tumour and osteotomy plane. These studies allowed the visualisation of the tumour and the application of a virtual osteotomy. The simulation was carried out by using a computer-aided design (CAD) software, Mimics (Materialise, Leuven, Belgium). Three-dimensional preoperative planning was obtained in CAD format. Next, 3D models were exported to CT data sets in Digital Imaging and Communications in Medicine (DICOM) format and uploaded to the navigation system (3D OrthoMap navigation software v1.0, Stryker Navigator, Freiburg, Germany). Using the standard navigation tools (navigated pointer, camera and infrared tracker devices applied to the patient) the surgeon was able to establish a correspondence in a computer monitor between 3D images and real bone. Once osteotomies were performed, the tumour surgical specimen obtained was CT scanned and 3D reconstructed similarly to what was done previously to surgery to CT images acquired with the preoperative protocol in patients. Results. The correlation between the osteotomies preoperatively planned and the osteotomies achieved by navigation was in a global mean of 0.73 millimeters (SD: 3.14) in a total of 6 planes evaluated. Conclusion. According to clinical relevance, this work shows an acceptable accuracy in preoperative planning and navigation. Furthermore, we demonstrate the usefulness of three-dimensional models of surgical specimens when surgeons need to determine quantitative and qualitative accuracy of 3D planning and navigation procedures

Background. Osteotomies around the knee have been used to correct lower limb mal-alignment for over 50 years. The procedure is technically demanding and carries specific risks of neurovascular injury, incorrect planning and execution, and insufficient fixation. In recent years, with the advent of locking plates, fixation techniques have improved significantly but the correct planning and execution of the operation remains difficult. Despite the availability of CT and MRI 3D imaging, surgical planning is still traditionally performed on 2D plain X-rays [1]. Especially with multi-planar deformities, this technique is prone to error. The aim of this clinical pilot study is to evaluate the feasibility of virtual pre-operative three-dimensional planning and correct execution of osteotomies around the knee with the aid of patient specific surgical guides and locking plates. Patients and methods. Eight consecutive patients, presenting with significant malalignment of the lower limb were included in the study. Pre-operative CT scans of the affected limb and the normal contra-lateral side were obtained and 3D models of the patient's anatomy were created, using dedicated software (Mimics® 3-matic®, Materialise, Leuven Belgium) [2]. These models were used to evaluate the required surgical correction. The healthy contralateral limb was mirrored and geometrically matched to the distal femur or proximal tibia of the healthy side. A virtual opening wedge correction of the affected bone was used to match the geometry of the healthy contralateral bone. Standard lower limb axes measurements confirmed correction of the alignment [3]. Based on the virtual plan, surgical guides were designed to perform the planar osteotomy and achieve the planned wedge opening and hinge axis orientation (see figure 1). Apart from guiding the osteotomy, the patient specific surgical guide also guided drilling of the planned screw holes. Post-operative assessment of the correction was obtained through planar X-rays, CT-scan and full leg standing X-ray. Results. One three-planar, three bi-planar and four single-plane osteotomies were performed. All guides could be used during surgery and served accurate guidance of the osteotomy plane and screwholes. The guides matched the bone very well in all cases without remaining toggle. The maximum deviation between the planned pre-operative wedge angle and the executed post-operative wedge angle was 1° in the coronal, sagittal and horizontal plane. The desired mechanical femorotibial axis on full-leg standing X-rays was achieved in 6 patients. Two patients were undercorrected by 1° and 2° respectively. No significant peri-operative complications occurred. Conclusion. 3D planning and guided correction of multi-planar deformity of femur or tibia is a feasible and accurate novel technique

Introduction. The intrinsic constraint of a total knee replacement (TKR) implant system is considered an important characteristic which plays a large role in determining stability following surgery. Established techniques for evaluating the constraint of TKR implants, as described in ASTM F 1223-14, do not necessarily map directly to physiologically relevant loading scenarios where instability can occur, and thus give an incomplete picture of the constraint characteristics of a candidate implant design. Sophisticated joint motion simulators now allow for more physiologically representative joint loading (eg. gait), including the contributions of virtual soft tissues. In this study, we employ a function-based constraint measurement technique for evaluating the kinematics of two TKR designs during gait. Furthermore, we employ simulated soft tissues in order to create three “virtual” knees on which the TKR are tested. Methods. The constraint characteristics of TKR implants were evaluated using a function-based measurement technique on a VIVO joint motion simulator (AMTI, Waltham, MA). The AVG75 standardized load and motion profiles for gait (Bergmann et al. 2014), were applied to an ultra-congruent cruciate-sacrificing TKR (Zimmer-Biomet, Warsaw, IN). Ligaments were simulated as point-to-point spring elements between the femur and tibia (3 bundles for MCL, 3 bundles for LCL). Ligament bundle origin, insertion, stiffness, and resting length properties were adapted from the publically available MB Knee project (. simtk.org/home/mb_knee. ) to create three knees. AP and IE kinematics were recorded during simulated gait after approximately 500 “learning” cycles at 0.75 Hz. Trials were then repeated with superimposed AP forces or IE torques. The amount of superimposed load varied with the amount of compressive load, such that the superimposed load was ±25 N AP force or ±1 Nm IE torque, per 1000 N of compressive force. AP and IE laxities were calculated based on changes in AP and IE motions, respectively (Fig 1). Experiments were repeated with a second TKR design; using the same femoral component but replacing the ultra-congruent UHMWPE bearing with a 3D printed ABS plastic bearing featuring a less congruent sagittal profile. In total, there were 2 implants × 3 virtual knees × 5 simulated loading profiles = 30 different simulated gait trials. Results. The baseline (normal gait) AP and IE motions for both TKR designs, averaged across three knees, are shown in Fig. 2. The average AP and IE laxities for each knee are shown in Table 1, with results averaged for each TKR design. Discussion. Differences in AP motion between the two TKR designs are large compared to the differences in IE motion. Predictably, the overall AP and IE motions and average laxities for the less congruent TKR are greater. While this trend was generally consistent across all knees, the actual differences in laxities between the two TKR designs varied between knees. This suggests that the importance of the intrinsic constraint of TKR varies on subject-to-subject basis, and thus variable soft tissue stabilization models should be considered during pre-clinical testing. For any figures or tables, please contact authors directly (see Info & Metrics tab above).

Eight consecutive patients with significant malalignment of the lower limb were included in the study. Pre-operative CT scans of the affected limb and the normal contra-lateral side were obtained and 3D models of the patient's anatomy were created, using dedicated software. The healthy contralateral limb was mirrored and geometrically matched to the distal femur or proximal tibia of the healthy side. A virtual opening wedge correction of the affected bone was used to match the geometry of the healthy contralateral bone. Standard lower limb axes measurements confirmed correction of the alignment. Based on the virtual plan, surgical guides were designed to perform the planar osteotomy and achieve the planned wedge opening and hinge axis orientation. The osteotomy was fixed with locking plates and screws. Post-operative assessment included planar X-rays, CT-scan and full leg standing X-rays. One three-planar, three bi-planar and four single-plane osteotomies were performed. Maximum weightbearing mechanical femoro-tibial coronal malalignment varied between 7° varus and 14° valgus (mean 7.6°, SD 3.1). Corrective angles varied from 7°–15°(coronal), 0°–13°(sagittal) and 0°–23°(horizontal). The maximum deviation between the planned pre-operative wedge angle and the executed post-operative wedge angle was 1° in the coronal, sagittal and horizontal plane. The desired mechanical femorotibial axis on full-leg standing X-rays was achieved in 6 patients. Two patients were undercorrected by 1° and 2° respectively. Conclusion. 3D planning and guided correction of multi-planar deformity of femur or tibia is a feasible and accurate novel technique

Purpose. The effects of Acetabular Rim Osteophytes (ARO) in Total Hip Arthroplasty (THA), has not been quantified. During THA their presence and location is variable, and the effect on post-operative Range of Motion (ROM) is unknown. The purpose of this study was to evaluate the ROM of a modern hip implant in five cadaver models utilizing computerized virtual surgery, and to analyze the effect of AROs given their location on the acetabulum, and position of the prosthesis during motion. Method. CT scans of five cadaveric pelvises and femurs were used to create 3-D Models. Surgery, using virtual Stryker components was then performed to restore the natural anatomic offset and leg length. ROM to impingement was evaluated for each model in eight vectors: flexion/extension, internal/external rotation, abduction/adduction, and 90 degrees of flexion with internal/external rotation. An Osteophyte Impingement Model was then created by elevating the natural acetabular rim by 10 millimeters circumferentially in each virtual cadaver pelvis. Using the same THA components, ROM was then evaluated in this pelvic model and compared to the cadaveric models. Results. ROM in the Osteophyte Impingement Model yielded a statistically significant decrease in five of the eight vectors tested, when compared to the Cadaveric Model: Flexion, Extension, External Rotation, Flexion to 90 degrees with Internal Rotation, and Flexion to 90 degrees with External Rotation. Only 3 of these 5 vectors were within normal human physiological ROM: Flexion, External Rotation, and Flexion to 90 degrees with Internal Rotation. The osteophyte model yielded a decrease in absolute ROM in the following: Flexion to 101 vs 113 degrees (p= 0.03), External Rotation to 30.4 vs 49.5 degrees (p= 0.01), and Flexion to 90 degrees with Internal Rotation 16.7 vs 31.6 degrees (p=0.01). When mapped on the acetabulum of right-sided hip, with the 12 o'clock position as the superior pole of the acetabulum, impingement on the osteophyte was noted at the following locations: with Flexion, and Flexion to 90 degrees with Internal Rotation, impinged was noted between 1 and 2 o'clock on the acetabulum. In External Rotation impinged occurred between 7 and 8 o'clock on the acetabulum. Conclusion. This study showed that a 10 millimeter osteophyte can potentially decrease range of motion and lead to impingement in THA in certain planes of motions: Flexion, External Rotation and Flexion to 90 degrees with Internal Rotation. The location of this impingement is between the 1 and 2 o'clock in Flexion, and Flexion to 90 degrees with Internal Rotation. In External Rotation, the impingement will occur between the 7 and 8 o'clock. The above applies to a right-sided acetabulum, the left side will demonstrate the mirror image of this impingement: Between the 10 to 11 o'clock, and 4 to 5 o'clock positions respectively. Osteophytes 10 millimeters or more in height at these positions should be carefully evaluated intra-operatively and removed safely if possible

Background. Surgical simulators allow learner-focussed skills training, in controllable and reproducible environments suitable for assessment. Aim. To research the face validity (extent to which the simulator resembles reality, determined subjectively by subjects), and construct validity, (ability to objectively differentiate between subjects with varying levels of arthroscopic experience) of a virtual reality arthroscopy simulator, to validate its effectiveness as an educational tool. Methods. Using the simulator insightArthroVR®, 37 subjects were required to perform diagnostic knee arthroscopy, palpate anatomical landmarks and complete questionnaires. The simulator recorded objective data to assess proficiency: time to complete tasks, roughness in instrument handling, and path length covered by the arthroscope and palpation probe. Results. The simulator succeeded in proving face validity: 86.4% participants agreed the simulator provided insight into arthroscopy. Training met the expectations of 91.3% and showed improvement in novices in simulated diagnostic arthroscopy in completion time (p-value=0.036), roughness (p-value=0.026), and path length covered by the arthroscope (p-value=0.008). Furthermore, the simulator was able to discriminate between experts, intermediates and novices, proving construct validity: time of completion (p-value=0.009), the path length covered by the arthroscope (p-value=0.02) and the probe (p-value=0.028). Conclusions. Results demonstrate the simulator succeeds in emulating real arthroscopy and can discriminate between subjects according to arthroscopic experience, proving face and construct validity. Further research on transfer of skills to the operating room needs to be done. With surgery constantly modernising and increasing time constraints with the EWTD, training must be efficient and assessable without compromising patient safety. Simulators could allow trainees earlier exposure to procedures, a wider range of pathologies in a compressed period, practice outside the OR, and an acceleration of the learning curve. This study has taken a step forward in validating a VR simulator and thus a step towards the future of simulation becoming an indispensable adjunct to surgical training

Computational modeling has been used to simulate the natural and prosthetic kinematic and kinetic function in an attempt to compare designs and/or predict a desired motion path from a design. The levels of soft tissue can range from basic ligaments (MCL, LCL, and ACL & PCL) to more complex models. The goal of this study was to evaluate the sensitivity of the Posterior Cruciate ligament in a virtual model and its effects on the kinematic outcome in a commercially available and validated kinematics package (KneeSim, LifeModeler San Clemente, CA). Methods:. KneeSIM is a musculoskeletal modeling environment that is built on the foundation of the ADAMS (MSC Software, Santa Ana CA), a rigid body dynamics solver to compute knee kinematics and forces during a deep knee bend. All parameters are customizable and can be altered by the user. Generic three dimensional models of cruciate retaining components of the femoral, tibial, and patellar are available with the software and were used to provide a common reference for the study. The following parameters were modified for each simulation to evaluate the sensitivity of the PCL in the model: 1) Model without PCL, 2) PCL with default properties, 3) PCL Shifted at femoral origin, 7 mm anterior, 7 mm inferior; tibial origin maintained; 4) PCL with increased stiffness properties (2x default), 5) position in the femur and tibia remained default position and 6) PCL with default properties and location, joint line shifted 4 mm superior. The standard output of tracking the flexion facet center (FFC) motion of the medial and lateral condyles was utilized (Figure 1). Results:. Figure 2 and 3 displays the output of the six conditions tested above. Comparing the curves for the medial and lateral motion show different patterns with the lateral point having more posterior translation than the medial. After approximately 95° of flexion, all cases exhibit an anterior translation in the model. This motion was consistent for all test cases. The model showed no difference with motion either with or without the PCL and with changing the stiffness. Altering the location of the PCL on the femoral insertion had the greatest effect on motion, while shifting the joint line superior was second. The shift of the ligament insertion and changing of the joint line results in the ligament being more parallel to the tibial surface which provides resistance to anterior motion or posterior translation. Discussion:. Although the model was able to discern differences, the inability to highlight variation in motion with and without the PCL suggests that the default parameters are not representative of an experimental or clinical setup. Although it is apparent that KneeSim can be used for comparative assessments between designs, simulations should be designed so as to provide similar boundary conditions. Publications (Colwell et al 2011) did successfully use KneeSim to provide a comparative assessment of CR components; however, only after the default model was altered to match the outcome of the experimental rig. Further analysis of the complexities in soft tissue modeling is warranted

The best treatment method of large acetabular bone defects at revision THR remains controversial. Some of the factors that need consideration are the amount of residual pelvic bone removed during revision; the contact area between the residual pelvic bone and the new implant; and the influence of the new acetabular construct on the centre of rotation of the hip. The purpose of this study was to compare these variables in two of the most used surgical techniques used to reconstruct severe acetabular defects: the trabecular metal acetabular revision system (TMARS) and a custom triflanged acetabular component (CTAC).

Pre- and post-operative CT-scans were acquired from 11 patients who underwent revision THR with a TMARS construct for a Paprosky IIIB defect, 10 with pelvic discontinuity, at Royal Adelaide Hospital. The CT scans were used to generate computer models to virtually compare the TMARS and CTAC constructs using a semi-automated method. The TMARS construct model was calculated using postoperative CT scans while the CTAC constructs using the preoperative CT scans. The bone contact, centre of rotation, inclination, anteversion and reamed bone differences were calculated for both models.

There was a significant difference in the mean amount of bone reamed for the TMARS reconstructions (15,997 mm³) compared to the CTAC reconstructions (2292 mm³, p>0.01). There was no significant difference between overall implant bone contact (TMARS 5760mm² vs CTAC 5447mm², p=0.63). However, there was a significant difference for both cancellous (TMARS 4966mm² vs CTAC 2887mm², p=0.008) and cortical bone contact (TMARS 795mm² vs CTAC 2560mm², p=0.001). There was no difference in inclination and anteversion achieved. TMARS constructs resulted on average in a centre of rotations 7.4mm more lateral and 4.0mm more posterior.

Modelling of two different reconstructions of Paprosky IIIB defects demonstrated potential important differences between all variables investigated.

Abstract

The Coronavirus pandemic mandated an immediate and dramatic change in the delivery of acute trauma services to minimise face-to-face contact. In our hospital, patients presenting to the Emergency Department with a knee injury and no fracture seen on Xrays were referred to a “Virtual Fracture Clinic” (VFC) where Xrays and clinical notes were reviewed by the duty Trauma and Orthopaedic Consultant the following working day. We present the outcomes of 101 consecutive patients managed through this process and deemed to have a “Soft Tissue Knee Injury” with a minimum follow-up of six months.

All Xrays were reviewed by a sub-specialist knee surgeon blinded to notes or clinical outcomes. Electronic clinical records were reviewed to determine further clinical appointments, surgical treatment and pending interventions.

Of 101 patients, the knee surgeon diagnosed 1 Fracture, 4 Lipo-haemarthroses, 41 significant effusions and 55 patients with normal Xrays. Correlation to urgent surgery was 100% for fracture (1/1), 25% for Lipo-haemarthrosis (1/4), 7.3% for significant effusion (3/41) and 9.1% for normal Xrays (5/55). A further 9.8% (4/41) of the “effusion” group and 7.3% (4/55) of the “normal” group were subsequently listed for non-urgent surgery.

Overall 17% (7/41) of “effusion” patients and 16% (9/55) of “normal” patients required surgery. Management plans from VFC varied within groups.

Acute “soft-tissue” injuries of the knee in adults cannot be reliably managed via VFC based on X-ray findings. A staged review by an appropriately trained health professional could reduce demand on acute knee surgical clinics and may enhance patient outcomes.

Introduction: After whiplash injuries the majority of patients complain of pain, muscular dysfunctions and restricted movement of the cervical spine, however, the cause of these symptoms cannot be diagnosed. Against this background, the hypothesis is formulated that functional disturbances in the form of pathological activities of the neck muscles occur as a result of a whiplash injury of the cervical spine. These pathological muscle activities can be demonstrated electromyographically and differ from the patterns of activity of healthy subjects. Study Objective: Thus, the aim of this study was to establish an electromyographical method for the diagnosis of functional disturbances of the neck muscles after whiplash injuries of the cervical spine. Material/Method: Primarily, an intramuscular recording of the electromyographical activity of the semispinalis capitis muscle was performed during flexion/extension and axial rotation in 46 patients with chronic symptoms after a whiplash injury of the cervical spine (QTF grade II) and 29 healthy subjects. The movement was controlled with techniques of virtual reality. The subject is immersed into a virtual outer space environment with a head-mounted display (HMD). In this virtual scene, the patient follows paths of motion of a signal (globe) with his/her gaze. A subsequent study was conducted to validate the results that had been obtained. For this purpose, the electromyographical activity of the semispinalis capitis muscle was recorded in another subject group (n=20) and patients with acute symptoms as a result of a whiplash injury of the cervical spine (QTF grade II) (n=35). Results: Compared to the physiological muscle activities that were established in the first subject group, changes could be observed in the chronic patient group. Subjects in our study, for instance, show a decrease in electrical activity during flexion and the resulting stretching of the semispinalis capitis muscle, while the same movement causes an increase in activity in patients. On the basis of these differences, 93 % of subjects (specificity) and 83 % of patients (sensitivity) could be classified correctly with a discriminance analysis. In the second study, the specificity was 88 % while a sensitivity of 86 % was determined in the acute patient population. Conclusion: The results of these investigations enable a highly specific and sensitive diagnosis of muscular dysfunctions on the basis of the intramuscular recordings of the electromyographical patterns of activity of the semispinalis capitis muscle

With increased shift working, multiple hand-overs, demand for trauma beds frequently outstripping supply, split-site working, shared care with other specialties and tertiary referrals awaiting transfer, keeping track of trauma patients can be difficult. To solve this problem we developed the Virtual Trauma Orthopaedic Management System (VTOMS) to monitor pre-operative trauma inpatients. VTOMS is a secure, networked system linked to the patient administration system (PAS). It can be accessed by the entire multidisciplinary team from any PC in the Trust. The main information is also displayed on plasma screens in the trauma unit. The status of patients requiring surgery is displayed (e.g. fit and ready, awaiting investigation, or unfit) with alerts on acutely unwell or unstable patients. Further details can be obtained by ‘drilling down’. The system has an inbuilt patient clock which ‘traffic lights’ patients awaiting theatre, providing a visual warning if waiting time is prolonged. Amber is set at 48 hours and red is 72 hours for most injuries. This facilitates real-time management of the trauma workload, allowing extra resources to be deployed early if it is seen that waiting times are climbing, or the case-mix is particularly complex. After successful use on trauma inpatients, the VTOMS system was extended to create a ‘virtual trauma ward’ where patients are pre-assessed in hospital and, if clinically appropriate, wait at home until a suitable theatre slot becomes available. The patient is contacted daily to monitor their clinical situation and brought in fasting on the morning of surgery. Using this ‘just in time’ philosophy 195 patients passed through our ‘virtual trauma ward’ in the six months to December 2009. The reduced length of stay saved 514 bed days, equivalent to £115,650 (£231,300 per annum), and minimised the impact of trauma on the elective service

Purpose: The purpose of this work was to compare the precision and reliability of screw fixation using two different guiding systems. The first system was based on computed tomography (CT) imaging and the second on digitalized fluoroscopic imaging.

Material and methods: Between 1998 and 2000, 88 patients underwent spinal fixation for diverse disease states (idiopathic scoliosis in 43, and fracture, spondylolisthesis or instability in 45). Pedicular screws (n = 223) were inserted in levels T4 to S1. The passive CT navigation system was used for 73 patients (177 pedicular screws) and the fluoroscopic navigation system for 15 (46 pedicular screws). An independent observer identified the position of the pedicular screws on the postoperative CT.

Results: Among the 73 patients who underwent a CT-guided procedure (177 pedicular screws) the rate of incorrect screw position was 6.2% (11/117) with = 2 mm penetration of the cortical. Among the 15 patients who underwent a fluoroscopy-guided procedure (46 pedicular screws), the rate of incorrect screw position was 17% (8/46) again with = 2 mm penetration of the cortical. For scoliosis patients, the rate of erroneous screw insertion was 6% for CT navigation and 28% for fluoroscopic navigation. For fractures and degenerative instability, the rates were 6% and 11% respectively.

Discussion: The passive nature of the two navigation systems used do not induce any peroperative constraint on the surgeon. With the CT system, landmarks have to be collected peroperatively on the posterior arch of the operated vertebra, a step that is not needed for the fluoroscopic system. The two techniques appear to be reliable for insertion of pedicular screws. We did not have any neurological disorders in this series. It can be recalled that the conventional method produces a 15 to 40% rate of erroneous insertion. The CT system provides better results for all types of diseases; the improvement is about 6%.

Conclusion: With CT-navigation, a large portion of the per-operative radiographs are no longer necessary. Operative time is slightly longer than for the classical procedure due to the collection of the 3D information, particularly important for scoliosis. With the fluoroscopy system, no special preoperative imaging is required. Two or three peroperative radiographs are sufficient, limiting irradiation during insertion of the pedicular screws. The fluoroscopic system does not however provide 3D images.

There is increasing pressure to develop virtual reality surgical simulation that can be used in surgical training. However, little is known of the attitudes of the surgical community towards such simulation, and which aspects of simulation are most important. A postal survey on attitudes to surgical simulation was sent to all New Zealand orthopaedic surgeons and advanced trainees. This comprised 44 questions in ten sections, using either a visual analogue scale (0 to 10) or free text box replies. Results were analysed for two sub-groups; surgeons qualified before 1990 and those qualified in or after 1990 or still in training. Of 208 possible responses, 142 were received, a response rate of 68%. Only 4 respondents had tried a surgical based simulator. Earlier qualified surgeons were more likely to agree that simulation was an effective way to practice surgical procedures, median score 7.7 versus 5.6 (p=0.03). Both groups thought the most important task for simulation was practicing angulation/spatial orientation (median score 8.4/10), while a realistic view of the operation was the most important requirement (median score 9/10). Both groups were unconvinced that simulation would impact on their practice in the next five years, with this statement being scored lower by later qualified surgeons, median score 2.4 versus 4.1 (p=0.04). Orthopaedic surgeons in New Zealand are supportive of surgical simulation but do not expect simulation to have an impact in the near future. Intriguingly, later qualified surgeons and trainees are more sceptical than their earlier qualified colleagues

Introduction. A stem extension improves fixation stability of a tibial component. We need caution not to contact the tibial cortex with an offset adaptor. A symmetric tibial stem design often requires the component's re-positioning with negative effects. Therefore, the objective of this study was to validate clinical efficacy of a tibial baseplate with asymmetric stemmed position (TB-ASP) using aligning outlier rate. We hypothesized that TB-ASP design will be better aligned without unessential offset adaptor than a tibial baseplate with symmetric stemmed position (TB-SSP). Methods. TB-ASP was designed based on the anthropometric standard model (58 female cadavers, 54.7±11.4 years)(Figure 1.). To validate the stem position, 3D bone models of 20 OA patients (71.8±7.2 years) was reconstructed. All virtual surgery has done by one surgeon with consistent surgical procedure for the analysis criteria. An analysis of TB-ASP's aligning outlier was proceeded by following steps; 1) aligning tibial baseplate to the line from medial 1/3 tuberosity to the center of PCL, 2) selecting tibial baseplate's size for maximal bone coverage without problematic overhang, 3) trying to displace tibial baseplate and stem extension(120mm long) not to contact tibial cortex. A case invading tibial cortex was considered to be an outlier. The ratio using offset adaptor was compared to those of TB-SSP. Statistical analysis was performed using paired t-test. Results. TB-ASP's stem was optimized 31% AP position from the anterior and 45% ML position from the lateral. Its aligning outlier rate was decreased by 35% comparing to that of TB-SSP. For the offset from tibial medullary center to the stem extension center, there was no significant difference(p=0.66<0.05) between TB-ASP(3.60±3.05) & TB-SSP(3.8±2.30). Discussion and Conclusion. TB-ASP design based on the standard model was better aligned with a proposed position of tibial stem. The findings from this study suggest that asymmetric tibial stem will improve the alignment without offset adaptor in total knee replacement. Significance. TB-ASP design can show better outlier rate and alignment comparing to TB-SSP. Our study results can expect to be used as basic data for TB-ASP design

Abstract

Objective: To evaluate if the complete resection of the femoral bump, in cam-type FAI increases the postoperative flexion and internal rotation. Material and Method: We reviewed 24 consecutive pre-operative and postoperative hip CT scans in 24 patients with FAI (22 male and 2 female, mean age 36.9 years) who underwent arthroscopic hip surgery for the removal of a bony prominence on the femoral neck-head junction. We measured the alpha angle in two places: in the classical location, in the mid plane of the femoral neck axis and proximally, in the same plane but in first quarter of the femoral neck height. Then we compared these results with the presence of a residual prominence diagnosed in the 3 dimensionally reconstructed images of the postoperative CT scan and the virtual range of motion of the 3D models using impaction detection software. Results: We found 7 cases with a residual bony prominence at the femoral neck-head junction in the 3D model of the proximal femur after the surgery. In this group the mean mid femoral neck alpha angle was significantly improved from 69.7° before the surgery to 48.3° (p=0.028), however the proximal alpha angle was not significantly improved 71.1° preoperative versus 62.7 (p=0.176) after the surgery. In the 17 patients without a residual bump, both alpha angles were improved, the mid alpha angle from 64.9° before the surgery to 40.76° (p=0.000) after the surgery and the proximal alpha angle from 65.8° to 38.4° (p=0.000). The range of motion of hip in the impaction detection software was also significantly improved in both groups, from flexion of 103° to 116° (p=0.001) in the group without a residual bump and from 102 to 118 (p=0.046) in the group with a residual bony prominence after the surgery. The internal rotation at 90° of flexion was also improved in both groups with a statistically significant difference (p=0.001 versus p=0.028 respectively). Conclusion: The complete arthroscopic resection of the femoral bump improves significantly the ranges of flex-ion and internal rotation in patients with cam-type FAI

We have investigated the benefits of patient specific instrument guides, applied to osteotomies around the knee. Single, dual and triple planar osteotomies were performed on tibias or femurs in 14 subjects. In all patients, a detailed pre-operative plan was prepared based upon full leg standing radiographic and CT scan information. The planned level of the osteotomy and open wedge resection was relayed to the surgery by virtue of a patient specific guide developed from the images. The mean deviation between the planned wedge angle and the executed wedge angle was 0° (-1 to 1, sd 0.71) in the coronal plane and 0.3° (-0.9 to 3, sd 1.14) in the sagittal plane. The mean deviation between the planned hip, knee, ankle angle (HKA) on full leg standing radiograph and the post-operative HKA was 0.3° (-1 to 2, sd 0.75). It is concluded that this is a feasible and valuable concept from the standpoint of pre-operative software based planning, surgical application and geometrical accuracy of outcome.

Cite this article: Bone Joint J 2013;95-B, Supple A:153–8.

Pertrochanteric femoral fractures are common and intramedullary nailing with a proximal femoral nail (PFNA®) is an accepted method for the surgical treatment. Accurate guide wire and subsequent hardware placement in the femoral neck is believed to be essential in order to avoid mechanical failure. Malpositioned implants may lead to rotational or angular malalignment or “cut out” in the femoral neck. Hip and knee arthritis might be a potential long-term consequence. The conventional technique might require multiple guidewire passes, and relies heavily on fluoroscopy. A computer-assisted surgical planning and navigation system based on 2D-fluoroscopy was developed in-house as an intraoperative guidance system for navigated guide wire placement in the femoral neck and head. To support the image acquisition process, the surgeon is supported by a so-called “zero-dose C-arm navigation” module. This tool enables a virtual radiation-free preview of the X-ray images of the femoral neck and head. The aim of this study was to compare PFNA® insertion using this system to conventional implantation technique. We hypothesised that guide wire and subsequent implant placement using our software decreases radiation exposure to the minimum of two images and reduces the number of drilling attempts. Furthermore, accuracy of implant placement in comparison to the conventional method might be improved and operation time shortened. We used 24 identical intact left femoral Sawbones® to simulate reduced pertrochanteric femoral fractures. First, we performed placement of the PFNA® into 12 Sawbones using the conventional fluoroscopic technique (group 1). Secondly, we performed placement of the PFNA® into 12 Sawbones guided by the computer-assisted surgical planning software (group 2). In each group, we first performed open and secondly minimal-invasive intramedullary nailing in six sawbones each. For minimal-invasive guide wire placement, a surgical drape imitated soft tissue coverage. Conventional and navigated technique used a C-arm fluoroscope (Siemens IsoC 3D®, Erlangen, Germany) in conventional 2D mode. Guidewire and subsequent blade placement in the femoral neck was evaluated. We documented: 1: the number of fluoroscopic images; 2: the total number of drilling attempts; 3: implant placement accuracy (3.1. Tip apex distance (TAD); 3.2. visible penetrations of the femoral neck and head; 3.3. blade-corticalis bone distance in the anteroposterior and lateral plane) and the 4: operation time. The number of fluoroscopic single shots taken to achieve an acceptable PFNA®-blade position was reduced significantly with computer-assistance by 71.5% (p<0.001) in the open and by 72,4% (p<0.001) in the minimally invasive technique. In each operation two X-rays for final documentation were taken. The average number of drilling attempts for the computer-guided system was significantly (p<0.05) less than that of the conventional technique in the minimally invasive procedure. The average number of drilling attempts showed no difference between the computer-assisted and conventional techniques in the open procedure. Accuracy of implant placement showed no difference between the computer-assisted and the conventional group. Computer assistance significantly increased the mean operation time for fixation of pertrochanteric femoral fractures with a PFNA® by 79.8% (p<0.001) in the open technique and by 54.4% (p<0.001) in the minimally invasive technique. Use of our computer-guided system for fixation of pertrochanteric femoral fractures by a PFNA® decreases the number of fluoroscopic single shots and of suboptimal guide wire passes while maintaining blade placement accuracy that is equivalent to the conventional technique. Computer-assisted surgery with our system increases the operation time and has just been tested in non-fractured sawbones. Although these results are promising, additional studies including fractured sawbones and cadaver models with extension of the navigation process to all steps of PFNA® introduction and with the goal of reducing the operation time are indispensable before integration of this navigation system into the clinical workflow

Summary

The mathematical model has proven to be highly accurate in measuring leg length before and after surgery to determine how leg length effects hip joint mechanics.

We sought to validate a method of measuring the range of motion of knees on radiographs as part of a new system of “Virtual Knee Clinics”.

The range of motion of 52 knees in 45 patients were first obtained clinically with goniometers and compared to radiographs of these patients' knees in full active flexion and extension. Four methods of plotting the range of motion on the radiographs were compared.

The intra-class correlation coefficient (ICC) for inter-rater reliability using the goniometer was very high; ICC=0.90 in extension and 0.85 in flexion. The best ICC for radiographic measurement in extension was 0.86 indicating substantial agreement and best ICC in flexion was 0.95 (method 4). ICC for intra-rater reliability was 0.98 for extension and 0.99 for flexion on radiographic measurements.

Measuring range of motion of the knee has never previously been validated in the literature. This study has allowed us to set up a “Virtual Knee Clinic,” combining postal questionnaires and radiographic measurements as a surrogate for knee function. We aim to maintain high quality patient surveillance following knee arthroplasty, reduce our new to follow-up ratios in line with Department of Health guidelines and improve patient satisfaction through reduced travel to hospital outpatients.

With 3D CT data of proximal femora it is possible to develop a computer programme for optimising femoral component fit and simulation of implantation. The implantation of the femoral stem can be simulated with any femoral component that has cortical press fit.

Five different currently used femoral components were virtually “implanted” in over 200 different femoral bone data. Optimal femoral fit was defined, when the component showed best diaphyseal and metaphyseal congruent contact with all CT data available. Position of neck and head were secondary, since an optimal press fit situation had priority in our set-up. Best fit was considered taken cortical contact and reconstruction of joint geometry into account.

There were numerous failures in all tested standard components, when correct angle of antetorsion, off-set, and leg length were expected. There were considerably better results with the use of CTX standard prosthesis (CTX-S).

The data of this study indicate a high proportion of less optimal fit with femoral standard components tested in this series. Indication for choosing CTX-S femoral components is dependent upon the individual geometry of dysplastic hip joint and the simulation results of standard components using the VIP method.

The Bernese periacetabular osteotomy (PAO) described by Ganz, et al. is a commonly used surgical intervention in hip dysplasia. PAO is being performed more frequently and is a viable alternative to hip arthroplasty for younger and more physically active patients. The procedure is challenging because pelvic anatomy is prohibitive to visibility and open access and requires four X-ray guided blind cuts around the acetabulum to free it from the hemi-pelvis. The crucial step is the re-orientation of the freed acetabulum to correct the inadequate coverage of the femoral head by idealy rotating the freed acetabular fragment.

Diagnosis and the decision for surgical intervention is currently based upon patient symptoms, use of two-dimensional (2D) radiographic measurements, and the intrinsic experience of the surgeon. With the advent of new technologies allowing three-dimensional reconstructions of hip anatomy, previous two-dimensional X-ray definitions have created much debate in standardizing numerical representations of hip dysplasia. Recent work done by groups such as Arminger et al. have combined and expanded two-dimensional measurements such as Center-Edge (CE) angle of Wiberg, Vertical-Center-Anterior margin (VCA) angle, Acetabular Anteversion (AcetAV) and applied them to three-dimensional CT rendering of hip anatomy. Further, variability in pelvic tilt is a confounding factor and has further impeded measurement translatability.

Computer assisted surgery (CAS) and navigation also called image-guided surgery (IGS) has been used in clinical cases of PAO with mixed results. The first appearing study of CAS/IGS in PAO was conducted by Langlotz, et. al 1997 and reported no clinical benefit to using CAS/IGS. However, they did conclude that the use of CAS/IGS is undoubtedly useful for surgeons starting this technically demanding procedure. This is supported by a more recent study done by Hsieh, et. al 2006 who conducted a two year randomised study of CAS/IGS in PAO and concluded its feasibility to facilitate PAO, but there was not an additional benefit when conventional PAO is done by an experienced surgeon. A study done by Peters, et. Al 2006 studying the learning curve necessary to become proficient at PAO found that “The occurrence of complications demonstrates a substantial learning curve” and thus makes a compelling argument for the use of CAS/IGS.

A major obstacle to navigation and CAS/IGS revolves around consistency, intra-operative time and ease of use. Custom made guides and implants may help circumvent these limitations. The use of CAS/CAM in developing custom made guides has been proven very successful in areas of oral maxillofacial surgery, hip arthroplasty, and knee replacement surgeries. Additionally, a significant study in the development of rapid prototyping guides in the treatment of dysplastic hip joints was done by Radermacher et. al 1998. They describe a process of using CAS/CAM within the operational theatre using a desktop planning station and a manufacturing unit to develop what they termed as “templates” to carry out a triple osteotomy.

Our group is evaluating and developing strategies in PAO using CAS/IGS and more recently using CAS and computer aided modeling (CAM) to develop custom made guides for acetabular positioning. Our first study (Burch et al.) focused on CAS/IGS in PAO using cadavers and yielded small mean cut (1.97± 0.73mm) and CE angle (4.9± 6.0) errors. Our recent study used full sized high-resolution foam pelvis models (Sawbones^®, Vashon, Washington) and used CAS/IGS to carry out the pelvic cuts and CAS/CAM to develop a acetabular positioning guide (APG) by rapid prototyping. The CAS/IGS pelvic cuts results were good (mean error of 3.18 mm ± 1.35) and support our and other studies done using CAS/IGS in PAO. The APG yielded high accuracy and was analysed using four angles with an overall mean angular error of 1.81 (0.55⁰)and individual angulation was as follows: CE 0.83° ± 0.53, S-AC 0.28° ± 0.19, AcetAV 0.41° ± 0.37, and VCA 0.68° ± 0.27. To our knowledge this is the first developed APG for PAO.

The APG we developed was to demonstrate the concept of using a positioning guide to obtain accurate rotation of the acetabular fragment. For a clinical application a refined and sleeker design would be required. Further, because working space within the pelvis is extraordinary constrained, once fitted the APG would need to remain and serve as an implantable cage capable of holding bone graft. A potential material is polyetheretherketone (PEEK). Customised PEEK implants and cages have been established in the literature and is a potential option for PAO. The benefits of an implant not only serve to constrain the acetabular fragment in the ideal position based upon the pre-operative plan, but may also provide the structural support for rotations not other wise possible.

Though CAS/IGS is a proven viable option, we envision a potentially simpler method for PAO, the use of a cut guide and an acetabular positioning implant. Using customized guides and implants could potentially circumvent the need for specialised intra-operative equipment and the associated learning curves, by providing guides that incorporate the pre-operational plan within the guide, constraining the surgeon to the desired outcome.

Telehealth has the potential to change the way we approach patient care. From virtual consenting to reducing carbon emissions, costs, and waiting times, it is a powerful tool in our clinical armamentarium. There is mounting evidence that remote diagnostic evaluation and decision-making have reached an acceptable level of accuracy and can safely be adopted in orthopaedic surgery. Furthermore, patients’ and surgeons’ satisfaction with virtual appointments are comparable to in-person consultations. Challenges to the widespread use of telehealth should, however, be acknowledged and include the cost of installation, training, maintenance, and accessibility. It is also vital that clinicians are conscious of the medicolegal and ethical considerations surrounding the medium and adhere strictly to the relevant data protection legislation and storage framework. It remains to be seen how organizations harness the full spectrum of the technology to facilitate effective patient care. Cite this article: Bone Joint J 2023;105-B(8):843–849

The 2020-2021 Canadian Residency Matching Service (CaRMS) match year was altered on an unprecedented scale. Visiting electives were cancelled at a national level, and the CaRMS interview tour was moved to a virtual model. These changes posed a significant challenge to both prospective students and program directors (PDs), requiring each party to employ alternative strategies to distinguish themselves throughout the match process. For a variety of reasons, including a decline in applicant interest secondary to reduced job prospects, the field of orthopaedic surgery was identified as vulnerable to many of these changes, creating a window of opportunity to evaluate their impacts on students and recruiting residency programs. This longitudinal survey study was disseminated to match-year medical students (3rd and 4th year) with an interest in orthopaedic surgery, as well as orthopaedic surgery program directors. Responses to the survey were collected using an electronic form designed in Qualtrics (Qualtrics, 2021, Provo, Utah, USA). Students were contacted through social media posts, as well as by snowball sampling methods through appropriate medical student leadership intermediates. The survey was disseminated to all 17 orthopedic surgery program directors in Canada. A pre-match and post-match iteration of this survey were designed to identify whether expectations differed from reality regarding the effect of the COVID-19 pandemic on the CaRMS match 2020-2021 process. A similar package was disseminated to Canadian orthopaedic surgery program directors pre-match, with an option to opt-in for a post-match survey follow-up. This survey had a focus on program directors’ opinions of various novel communication, recruitment, and assessment strategies, in the wake of the COVID-19 pandemic. Students’ responses to the loss of visiting electives were negative. Despite a reduction in financial stress associated with reduced need to travel (p=0.001), this was identified as a core component of the clerkship experience. In the case of virtual interviews, students’ initial trepidation pre-CaRMS turned into a positive outlook post-CaRMS (significant improvement, p=0.009) indicating an overall satisfaction with the virtual interview format, despite some concerns about a reduction in their capacity to network. Program directors and selection committee faculty also felt positively about the virtual interview format. Both students and program directors were overwhelmingly positive about virtual events put on by both school programs and student-led initiatives to complement the CaRMS tour. CaRMS was initially developed to facilitate the matching process for both students and programs alike. We hope to continue this tradition of student-led and student-informed change by providing three evidence-based recommendations. First, visiting electives should not be discontinued in future iterations of CaRMS if at all possible. Second, virtual interviews should be considered as an alternative approach to the CaRMS interview tour moving forward. And third, ongoing virtual events should be associated with a centralized platform from which programs can easily communicate virtual sessions to their target audience

Introduction: The centre provides hand services to remote hospitals which require patients to travel long distances at odd hours for assessment and consenting to their operation only to be done at a later date in day surgery unit unless otherwise indicated.

Aims: Compare video conferencing to patient and surgeon ‘face to face’ consultation in counselling of patients prior to surgery.

Methods: Four injuries (Nail bed, extensor tendon, nerve repair, wrist laceration) were identified for which operative management was clear. 10 plastic surgery SHOs were shown photographs of the patients injury and asked to ‘counsel’ the ‘patient’(played by consultant plastic surgeon) with regards to the intended benefits, risks and complications of surgery.

The assessment was done for all four scenarios both in person and over a video conference link (AHMS). The order of each case was varied to minimise ‘rehearsal’ of the consent. The consent process was scored on a number of points followed by rating. SHOs acted as their own controls removing bias of differing levels of knowledge.

Results: The mean counselling time was 6 minutes/session. Equipments functioned reliably with audio and speed rated as excellent. Quality of councelling sessions using telemedicine was considered by consultants as good (32/40) to satisfactory (8/40) and was found comparable to in person councelling in obtaining consent.

Conclusion: Telemedicine is as effective as specialist-on site counselling for non-controversial hand injuries and thereby reduces the movement of patients from remote A& E departments to plastic surgery units for consent and booking of their surgery.

Aims. The aims of this study were: 1) to describe extended restricted kinematic alignment (E-rKA), a novel alignment strategy during robotic-assisted total knee arthroplasty (RA-TKA); 2) to compare residual medial compartment tightness following virtual surgical planning during RA-TKA using mechanical alignment (MA) and E-rKA, in the same set of osteoarthritic varus knees; 3) to assess the requirement of soft-tissue releases during RA-TKA using E-rKA; and 4) to compare the accuracy of surgical plan execution between knees managed with adjustments in component positioning alone, and those which require additional soft-tissue releases. Methods. Patients who underwent RA-TKA between January and December 2022 for primary varus osteoarthritis were included. Safe boundaries for E-rKA were defined. Residual medial compartment tightness was compared following virtual surgical planning using E-rKA and MA, in the same set of knees. Soft-tissue releases were documented. Errors in postoperative alignment in relation to planned alignment were compared between patients who did (group A) and did not (group B) require soft-tissue releases. Results. The use of E-rKA helped restore all knees within the predefined boundaries, with appropriate soft-tissue balancing. E-rKA compared with MA resulted in reduced residual medial tightness following surgical planning, in full extension (2.71 mm (SD 1.66) vs 5.16 mm (SD 3.10), respectively; p < 0.001), and 90° of flexion (2.52 mm (SD 1.63) vs 6.27 mm (SD 3.11), respectively; p < 0.001). Among the study population, 156 patients (78%) were managed with minor adjustments in component positioning alone, while 44 (22%) required additional soft-tissue releases. The mean errors in postoperative alignment were 0.53 mm and 0.26 mm among patients in group A and group B, respectively (p = 0.328). Conclusion. E-rKA is an effective and reproducible alignment strategy during RA-TKA, permitting a large proportion of patients to be managed without soft-tissue releases. The execution of minor alterations in component positioning within predefined multiplanar boundaries is a better starting point for gap management than soft-tissue releases. Cite this article: Bone Jt Open 2024;5(8):628–636

Aims. The aim of this modified Delphi process was to create a structured Revision Hip Complexity Classification (RHCC) which can be used as a tool to help direct multidisciplinary team (MDT) discussions of complex cases in local or regional revision networks. Methods. The RHCC was developed with the help of a steering group and an invitation through the British Hip Society (BHS) to members to apply, forming an expert panel of 35. We ran a mixed-method modified Delphi process (three rounds of questionnaires and one virtual meeting). Round 1 consisted of identifying the factors that govern the decision-making and complexities, with weighting given to factors considered most important by experts. Participants were asked to identify classification systems where relevant. Rounds 2 and 3 focused on grouping each factor into H1, H2, or H3, creating a hierarchy of complexity. This was followed by a virtual meeting in an attempt to achieve consensus on the factors which had not achieved consensus in preceding rounds. Results. The expert group achieved strong consensus in 32 out of 36 factors following the Delphi process. The RHCC used the existing Paprosky (acetabulum and femur), Unified Classification System, and American Society of Anesthesiologists (ASA) classification systems. Patients with ASA grade III/IV are recognized with a qualifier of an asterisk added to the final classification. The classification has good intraobserver and interobserver reliability with Kappa values of 0.88 to 0.92 and 0.77 to 0.85, respectively. Conclusion. The RHCC has been developed through a modified Delphi technique. RHCC will provide a framework to allow discussion of complex cases as part of a local or regional hip revision MDT. We believe that adoption of the RHCC will provide a comprehensive and reproducible method to describe each patient’s case with regard to surgical complexity, in addition to medical comorbidities that may influence their management. Cite this article: Bone Jt Open 2022;3(5):423–431

Abstract. Introduction. A spotlight has been placed upon virtual assessment of patients during the coronavirus pandemic. This has been particularly prevalent in the assessment of acute knee injuries. In this study we aim to assess the accuracy of telephone triage, confirmed by Magnetic Resonance Imaging (MRI) in the diagnosis of acute knee injuries. Methods. Case records of patients triaged by telephone in the acute knee clinic at Leeds General Infirmary were analysed. Provisional diagnoses made following telephone triage were compared to radiological diagnoses made on subsequent MRI scans. Diagnostic accuracy was compared between those patients assessed virtually and those assessed in face-to-face clinics. Results. 1160 patients were referred to the acute knee injury clinic during the study period. 587 of these were triaged telephonically. MRI scans were requested for 107 (18%) virtually reviewed patients. Of these patients, 92 (79%) had an MRI scan requested after making a provisional diagnosis over the phone. Of the MRI requests made after virtual consultation, there was a 75% diagnostic accuracy of the pre-imaging diagnosis. Of the patients seen in face-to-face appointments, a diagnostic accuracy of 73% was observed. Conclusion. Virtual assessment can provide an efficient and cost-effective establishment of diagnosis of acute knee injuries whilst reducing hospital attendance. A combination of virtual and in-person clinics may allow quicker access to specialist opinion and therefore reduce patient waiting times

Aims. This study was designed to develop a model for predicting bone mineral density (BMD) loss of the femur after total hip arthroplasty (THA) using artificial intelligence (AI), and to identify factors that influence the prediction. Additionally, we virtually examined the efficacy of administration of bisphosphonate for cases with severe BMD loss based on the predictive model. Methods. The study included 538 joints that underwent primary THA. The patients were divided into groups using unsupervised time series clustering for five-year BMD loss of Gruen zone 7 postoperatively, and a machine-learning model to predict the BMD loss was developed. Additionally, the predictor for BMD loss was extracted using SHapley Additive exPlanations (SHAP). The patient-specific efficacy of bisphosphonate, which is the most important categorical predictor for BMD loss, was examined by calculating the change in predictive probability when hypothetically switching between the inclusion and exclusion of bisphosphonate. Results. Time series clustering allowed us to divide the patients into two groups, and the predictive factors were identified including patient- and operation-related factors. The area under the receiver operating characteristic (ROC) curve (AUC) for the BMD loss prediction averaged 0.734. Virtual administration of bisphosphonate showed on average 14% efficacy in preventing BMD loss of zone 7. Additionally, stem types and preoperative triglyceride (TG), creatinine (Cr), estimated glomerular filtration rate (eGFR), and creatine kinase (CK) showed significant association with the estimated patient-specific efficacy of bisphosphonate. Conclusion. Periprosthetic BMD loss after THA is predictable based on patient- and operation-related factors, and optimal prescription of bisphosphonate based on the prediction may prevent BMD loss. Cite this article: Bone Joint Res 2024;13(4):184–192

Aims. This study aimed to investigate the estimated change in primary and revision arthroplasty rate in the Netherlands and Denmark for hips, knees, and shoulders during the COVID-19 pandemic in 2020 (COVID-period). Additional points of focus included the comparison of patient characteristics and hospital type (2019 vs COVID-period), and the estimated loss of quality-adjusted life years (QALYs) and impact on waiting lists. Methods. All hip, knee, and shoulder arthroplasties (2014 to 2020) from the Dutch Arthroplasty Register, and hip and knee arthroplasties from the Danish Hip and Knee Arthroplasty Registries, were included. The expected number of arthroplasties per month in 2020 was estimated using Poisson regression, taking into account changes in age and sex distribution of the general Dutch/Danish population over time, calculating observed/expected (O/E) ratios. Country-specific proportions of patient characteristics and hospital type were calculated per indication category (osteoarthritis/other elective/acute). Waiting list outcomes including QALYs were estimated by modelling virtual waiting lists including 0%, 5% and 10% extra capacity. Results. During COVID-period, fewer arthroplasties were performed than expected (Netherlands: 20%; Denmark: 5%), with the lowest O/E in April. In the Netherlands, more acute indications were prioritized, resulting in more American Society of Anesthesiologists grade III to IV patients receiving surgery. In both countries, no other patient prioritization was present. Relatively more arthroplasties were performed in private hospitals. There were no clinically relevant differences in revision arthroplasties between pre-COVID and COVID-period. Estimated total health loss depending on extra capacity ranged from: 19,800 to 29,400 QALYs (Netherlands): 1,700 to 2,400 QALYs (Denmark). With no extra capacity it will take > 30 years to deplete the waiting lists. Conclusion. The COVID-19 pandemic had an enormous negative effect on arthroplasty rates, but more in the Netherlands than Denmark. In the Netherlands, hip and shoulder patients with acute indications were prioritized. Private hospitals filled in part of the capacity gap. QALY loss due to postponed arthroplasty surgeries is considerable. Cite this article: Bone Jt Open 2022;3(12):977–990

Adult Spine Deformity (ASD) is a degenerative condition of the adult spine leading to altered spine curvatures and mechanical balance. Computational approaches, like Finite Element (FE) Models have been proposed to explore the etiology or the treatment of ASD, through biomechanical simulations. However, while the personalization of the models is a cornerstone, personalized FE models are cumbersome to generate. To cover this need, we share a virtual cohort of 16807 thoracolumbar spine FE models with different spine morphologies, presented in an online user-interface platform (SpineView). To generate these models, EOS images are used, and 3D surface spine models are reconstructed. Then, a Statistical Shape Model (SSM), is built, to further adapt a FE structured mesh template for both the bone and the soft tissues of the spine, through mesh morphing. Eventually, the SSM deformation fields allow the personalization of the mean structured FE model, leading to generate FE meshes of thoracolumbar spines with different morphologies. Models can be selectively viewed and downloaded through SpineView, according to personalized user requests of specific morphologies characterized by the geometrical parameters: Pelvic Incidence; Pelvic Tilt; Sacral Slope; Lumbar Lordosis; Global Tilt; Cobb Angle; and GAP score. Data quality is assessed using visual aids, correlation analyses, heatmaps, network graphs, Anova and t-tests, and kernel density plots to compare spinopelvic parameter distributions and identify similarities and differences. Mesh quality and ranges of motion have been assessed to evaluate the quality of the FE models. This functional repository is unique to generate virtual patient cohorts in ASD. Acknowledgements: European Commission (MSCA-TN-ETN-2020-Disc4All-955735, ERC-2021-CoG-O-Health-101044828)

Ideally the hip arthroplasty should not be subject to bony or prosthetic impingement, in order to minimise complications and optimise outcomes. Modern 3d planning permits pre-operative simulation of the movements of the planned hip arthroplasty to check for such impingement. For this to be meaningful, however, it is necessary to know the range of movement (ROM) that should be simulated. Arbitrary “normal” values for hip ROM are of limited value in such simulations: it is well known that hip ROM is individualised for each patient. We have therefore developed a method to determine this individualised ROM using CT scans. CT scans were performed on 14 cadaveric hips, and the images were segmented to create 3d virtual models. Using Matlab software, each virtual hip was moved in all potential directions to the point of bony impingement, thus defining an individualised impingement-free 3d ROM envelope. This was then compared with the actual ROM as directly measured from each cadaver using a high-resolution motion capture system. For each hip, the ROM envelope free of bony impingement could be described from the CT and represented as a 3d shape. As expected, the directly measured ROM from the cadaver study for each hip was smaller than the CT-based prediction, owing to the presence of constraining soft tissues. However, for movements associated with hip dislocation (such as flexion with internal rotation), the cadaver measurements matched the CT prediction, to within 10°. It is possible to determine an individual's range of clinically important hip movements from a CT scan. This method could therefore be used to create truly personalised movement simulation as part of pre-operative 3d surgical planning

Aims. The COVID-19 pandemic has triggered transformative change in how clinicians interact with their patients. There has been a shift away from face-to-face toward virtual consultations. However, the evidence to support this change in practice is unclear. The aim of this study was to systematically review the evidence base for virtual consultations for orthopaedics. Materials and Methods. Two independent reviewers performed a literature search based on PRISMA guidelines, utilizing the MEDLINE, EMBASE and Scopus databases. Only studies reporting outcomes following the use of telemedicine for diagnosis, consultation, rehabilitation, and follow-up were included. Outcomes analyzed were: 1) Patient and clinician satisfaction, 2) Clinical outcome measures, and 3) Cost analysis of traditional vs teleconsultation. Results. A total of 41 studies were included. Fifteen studies compared clinical outcomes of telemedicine against a matched traditional cohort. Of these 15 studies, two demonstrated non-inferiority, nine showed no statistically significant difference and four found telemedicine to be superior. Eleven studies recorded patient reported outcomes, which demonstrated high patient satisfaction. Nine studies reported decreased costs when telemedicine was compared to traditional care. The remaining 6 studies had varied aims and methodologies that didn't fit well with any of these sub-headings. Conclusion. While the available evidence is limited, the studies assessed in this systematic review show that telemedicine can deliver high quality healthcare with good clinical outcomes and high patient satisfaction in a cost effective manner. Further studies are required to validate telemedicine for specific trauma and orthopaedic diagnoses