Abstract. Objectives. Sarcopenia is characterised by generalised progressive loss of physical performance, skeletal muscle mass and strength. This systematic review evaluated the effects of sarcopenia on postoperative functional recovery outcomes and mortality in patients undergoing orthopaedic surgery and secondarily assessed the methods used to diagnose and define sarcopenia in orthopaedic literature. Methods. A systematic search was conducted in MEDLINE, EMBASE and Google Scholar databases according to the PRISMA guidelines. Studies involving sarcopenic patients who underwent defined orthopaedic surgery and recorded postoperative outcomes were included. The quality of the criteria by which a sarcopenia diagnosis was made was evaluated and publication quality was assessed using Newcastle-Ottawa Scale. Results. A total of 365 studies were identified and screened, 26 full text records were reviewed and 19 publications included in the analysis. Papers reflected a variety of orthopaedic interventions, primarily for elderly trauma or degenerative conditions. Mean follow up was 1.9 years (SD: 1.9 years). There was wide heterogeneity in measurement tools and evaluated parameters across the included papers, however sarcopenia was associated with at least one deleterious effect on surgical outcomes in all 19 studies. Post-operative mortality rate was reported in 11 papers and sarcopenia was associated with poorer survival in 73% (8/11) of them. The most used outcome was the Barthel index (4/19) and sarcopenic patients recorded lower scores in 75% (3/4) of these. Sarcopenia was defined using the gold standard three parameters in 21% (4/19) of studies, using two parameters in 21% (4/19) studies and one in the remaining 58% (11/19). The methodological quality of included papers was moderate to high. Conclusions. The literature base suffers from heterogeneity in outcomes and classification of sarcopenia diagnosis parameters, however available data suggests that sarcopenia generally increases postoperative mortality and impairs recovery. Sarcopenic patients could be targeted with pre-operative interventions, aiming to improve outcomes

Introduction. Ischaemic preconditioning (IPC) is a phenomenon whereby a tissue is more tolerant to an insult if it is first subjected to short bursts of sublethal ischaemia and reperfusion. The potential of this powerful mechanism has been realised in many branches of medicine where there is an abundance of ongoing research. However, there has been a notable lack of development of the concept in Orthopaedic surgery. The routine use of tourniquet-controlled limb surgery and traumatic soft tissue damage are just two examples of where IPC could be utilised to beneficial effect in Orthopaedic surgery. Methods. We conducted a randomized controlled clinical trial looking at the role of a delayed remote IPC stimulus on a cohort of patients undergoing a total knee arthroplasty (TKA). We measured the effect of IPC by analysing gene expression in skeletal muscle samples from these patients. Specifically we looked at the expression of Heat shock protein-90 (HSP-90), Catalase and Cyclo-oxygenase-2 (COX-2) at the start of surgery and at one hour into surgery. Gene analysis was performed using real time polymerase chain reaction amplification. As a second arm to the project we developed an in-vitro model of IPC using a human skeletal muscle cell line. A model was developed, tested and subsequently used to produce a simulated IPC stimulus prior to a simulated ischaemia-reperfusion (IR) injury. The effect of this on cell viability was investigated using crystal violet staining. Results. In the clinical arm of the study 4 patients were randomized to a control group and 4 randomized to IPC. Operative and post-operative periods were without any adverse incident. For each gene in question there was a different pattern in expression. COX-2 showed an initial up-regulation of 1.43 (p=0.83) at the start of surgery and a subsequent down-regulation of 0.07 (p=0.01) at one hour into surgery. Catalase expression was lower than control at the start of surgery (0.62, p= 0.46) and at one hour into surgery (0.5, p=0.1). HSP-90 expression was initially lower than control at the start of surgery (0.59, p= 0.07) then up-regulated at one hour into surgery (1.13, p=0.62). In the in-vitro section of the study we found that 15 hours of simulated ischaemia was required for a cell death of approximately 50 % (p=0.00001). The introduction of a simulated IPC stimulus increased cell death at a 1 hour reperfusion time-point (IPC group had 18% more cell death than IR group, p=0.003) and at a 24 hour reperfusion time-point (IPC group had 19% more cell death than IR group, p= 0.00001). At a 72 hours reperfusion time-point the IPC group had a 30% greater survival than the IR group (p=0.000006). Conclusion. Our clinical study was subject to small sample size. Despite this it suggests a particular importance of COX-2 in the IPC mechanism. The in-vitro model we developed is an essential resource for further studies into IPC in Orthopaedic Surgery. Preliminary results from this model point towards the ‘second window of protection’ of IPC as a stronger phenomenon than immediate preconditioning

Among the advanced technology developed and tested for orthopaedic surgery, the Rizzoli (IOR) has a long experience on custom-made design and implant of devices for joint and bone replacements. This follows the recent advancements in additive manufacturing, which now allows to obtain products also in metal alloy by deposition of material layer-by-layer according to a digital model. The process starts from medical image, goes through anatomical modelling, prosthesis design, prototyping, and final production in 3D printers and in case post-production. These devices have demonstrated already to be accurate enough to address properly the specific needs and conditions of the patient and of his/her physician. These guarantee also minimum removal of the tissues, partial replacements, no size related issues, minimal invasiveness, limited instrumentation. The thorough preparation of the treatment results also in a considerable shortening of the surgical and of recovery time. The necessary additional efforts and costs of custom-made implants seem to be well balanced by these advantages and savings, which shall include the lower failures and revision surgery rates. This also allows thoughtful optimization of the component-to-bone interfaces, by advanced lattice structures, with topologies mimicking the trabecular bone, possibly to promote osteointegration and to prevent infection. IOR's experience comprises all sub-disciplines and anatomical areas, here mentioned in historical order. Originally, several systems of Patient-Specific instrumentation have been exploited in total knee and total ankle replacements. A few massive osteoarticular reconstructions in the shank and foot for severe bone fractures were performed, starting from mirroring the contralateral area. Something very similar was performed also for pelvic surgery in the Oncology department, where massive skeletal reconstructions for bone tumours are necessary. To this aim, in addition to the standard anatomical modelling, prosthesis design, technical/technological refinements, and manufacturing, surgical guides for the correct execution of the osteotomies are also designed and 3D printed. Another original experience is about en-block replacement of vertebral bodies for severe bone loss, in particular for tumours. In this project, technological and biological aspects have also been addressed, to enhance osteointegration and to diminish the risk of infection. In our series there is also a case of successful custom reconstruction of the anterior chest wall. Initial experiences are in progress also for shoulder and elbow surgery, in particular for pre-op planning and surgical guide design in complex re-alignment osteotomies for severe bone deformities. Also in complex flat-foot deformities, in preparation of surgical corrections, 3D digital reconstruction and 3D printing in cheap ABS filaments have been valuable, for indication, planning of surgery and patient communication; with special materials mimicking bone strength, these 3D physical models are precious also for training and preparation of the surgery. In Paediatric surgery severe multi planar & multifocal deformities in children are addressed with personalized pre-op planning and custom cutting-guides for the necessary osteotomies, most of which require custom allografts. A number of complex hip revision surgeries have been performed, where 3D reconstruction for possible final solutions with exact implants on the remaining bone were developed. Elective surgery has been addressed as well, in particular the customization of an original total ankle replacement designed at IOR. Also a novel system with a high-tibial-osteotomy, including a custom cutting jig and the fixation plate was tested. An initial experience for the design and test of custom ankle & foot orthotics is also in progress, starting with 3D surface scanning of the shank and foot including the plantar aspect. Clearly, for achieving these results, multi-disciplinary teams have been formed, including physicians, radiologists, bioengineers and technologists, working together for the same goal

Objectives. The period of post-operative treatment before surgical wounds are completely closed remains a key window, during which one can apply new technologies that can minimise complications. One such technology is the use of negative pressure wound therapy to manage and accelerate healing of the closed incisional wound (incisional NPWT). . Methods. We undertook a literature review of this emerging indication to identify evidence within orthopaedic surgery and other surgical disciplines. Literature that supports our current understanding of the mechanisms of action was also reviewed in detail. . Results. A total of 33 publications were identified, including nine clinical study reports from orthopaedic surgery; four from cardiothoracic surgery and 12 from studies in abdominal, plastic and vascular disciplines. Most papers (26 of 33) had been published within the past three years. Thus far two randomised controlled trials – one in orthopaedic and one in cardiothoracic surgery – show evidence of reduced incidence of wound healing complications after between three and five days of post-operative NPWT of two- and four-fold, respectively. Investigations show that reduction in haematoma and seroma, accelerated wound healing and increased clearance of oedema are significant mechanisms of action. . Conclusions. There is a rapidly emerging literature on the effect of NPWT on the closed incision. Initiated and confirmed first with a randomised controlled trial in orthopaedic trauma surgery, studies in abdominal, plastic and vascular surgery with high rates of complications have been reported recently. The evidence from single-use NPWT devices is accumulating. There are no large randomised studies yet in reconstructive joint replacement. Cite this article: Bone Joint Res 2013;2:276–84

A number of advantages of unicondylar arthroplasty (UKA) over total knee arthroplasty in patients presenting osteoarthritis in only a single compartment have been identified in the literature. However, accurate implant positioning and alignment targets, which have been shown to significantly affect outcomes, are routinely missed by conventional techniques. Computer Assisted Orthopaedic Surgery (CAOS) has demonstrated its ability to improve implant accuracy, reducing outliers. Despite this, existing commercial systems have seen extremely limited adoption. Survey indicates the bulk, cost, and complexity of existing systems as inhibitive characteristics. We present a concept system based upon small scale head mounted tracking and augmented reality guidance intended to mitigate these factors. A visible-spectrum stereoscopic system, able to track multiple fiducial markers to 6DoF via photogrammetry and perform semi-active speed constrained resection, was combined with a head mounted display, to provide a video-see-through augmented reality system. The accuracy of this system was investigated by probing 180 points upon a 110×110×50 mm known geometry and performing controlled resection upon a 60×60×15 mm bone phantom guided by an overlaid augmented resection guide that updated in real-time. The system produced an RMS probing accuracy and precision of 0.55±0.04 and 0.10±0.01 mm, respectively. Controlled resection resulted in an absolute resection error of 0.34±0.04 mm with a general trend of over-resection of 0.10±0.07 mm. The system was able to achieve the sub-millimetre accuracy considered necessary to successfully position unicondylar knee implants. Several refinements of the system, such as pose filtering, are expected to increase the functional volume over which this accuracy is obtained. The presented system improves upon several objections to existing commercial CAOS UKA systems, and shows great potential both within surgery itself and its training. Furthermore, it is suggested the system could be readily extended to additional orthopaedic procedures requiring accurate and intuitive guidance

Background and Aims. Many orthopaedic patients admitted to hospital who require urgent surgery are also on Warfarin. Patients with an INR>2 have an increased risk of bleeding complications during surgery; however delay to surgery due to a high INR has both clinical and financial implications. This audit evaluates whether the appropriate management for correction of INR is employed as per local guidelines and, if not, whether this results in significant delay to operative treatment. Methods. A retrospective and prospective audit was performed analysing all Orthopaedic trauma admissions admitted to University Hospital Aintree in a 5 month period. Only those solely on warfarin, who were not acutely bleeding and required surgery in <24 hours were included. Results. A sample of 17 patients was obtained of which only 35.3% had correct INR reversal as per local guidelines. Errors that occurred included 81.1% not being given further Vitamin K at reassessment, 18.2% given too much Vitamin K, 9.1% given too little Vitamin K, 18.2% given Octaplex incorrectly and 9.1% not given Octaplex when indicated. Only 1 patient had a delay to their surgery directly resulting from incorrect INR reversal (total time to surgery − 33 hours 45 minutes). Conclusion. Better education for clinical staff on the local policy for INR reversal in patients requiring urgent orthopaedic surgery is needed. Local policy guidelines have since been redesigned in light of these results and a completion audit cycle has been performed showing significant improvement with 50% of the patient sample given correct INR reversal

There has been a recent surge in the creation of medical student-led and foundation trainees-led research collaboratives in surgery. These have mainly been in general surgery. The current study therefore explores the value and feasibility of such collaboratives, highlighting the scope for a similar idea in orthopaedics. Research Collaborative organisations were systematically searched and reviewed to check whether medical students or junior doctors prior to speciality training led them. The advertised research projects and subsequent publication productivity for each identified organisation was also evaluated using the information presented on their websites. Two medical student-led research collaborative organisations and 1 medical student and foundation trainees-led research collaborative were identified. All of which are in general surgery and none in trauma and/or orthopaedics surgery. These include STARSurg, EuroSurg and GlobalSurg respectively. A total of 6 research collaborative projects were identified with 3 leading to subsequent publications. This study highlights the value and feasibility of medical students- and foundation trainees-driven high quality surgical research collaborative. It also emphasises the growing contribution of medical students towards research and policymaking in our global health system, an aspect that may be absent or delayed in the field of orthopaedics. We therefore, explore the idea as well as the need to instigate a similar collaboration in the field of trauma and orthopaedic surgery

In the last years, 3d printing has progressively grown and it has reached a solid role in clinical practice. The main applications brought by 3d printing in orthopedic surgery are: preoperative planning, custom-made surgical guides, custom-made im- plants, surgical simulation, and bioprinting. The replica of the patient's anatomy, starting from the elaboration of medical volumetric images (CT, MRI, etc.), allows a progressive extremization of treatment personalization that could be tailored for every single patient. In complex cases, the generation of a 3d model of the patient's anatomy allows the surgeons to better understand the case — they can almost “touch the anatomy” —, to perform a more ac- curate preoperative planning and, in some cases, to perform device positioning before going to the surgical room (i.e. joint arthroplasty). 3d printing is also commonly used to produce surgical cutting guides, these guides are positioned intraoperatively on given landmarks to guide the surgeon to perform a specific surgical act (bone osteotomy, bone resection, implant position, etc.). In total knee arthroplasty, custom-made cutting guides have been developed to help the surgeon align the femoral and tibial components to the pre-arthritic condition with- out the use of the intramedullary femoral guide. 3d printed custom-made implants represent an emerging alternative to biological reconstructions especially after oncologic resection surgery or in case of complex arthroplasty revision surgery. Custom-made implants are designed to re- place the original shape and size of the patient's bone and they allow an extreme personalization of the treatment for every single patient. Patient-specific surgical simulation is a new frontier that promises great benefits for surgical training. a solid 3d model of the patient's anatomy can faithfully reproduce the surgical complexity of the patient and it allows to generate surgical simulators with increasing difficulty to adapt the difficulties of the course with the level of the trainees performing structured training paths: from the “simple” case to the “complex” case.

Infections represent a devastating complication in orthopedic and traumatological surgery, with high rates of morbidity and mortality. An early intervention is essential, and it includes a radical surgical approach supported by targeted intravenous antimicrobial therapy. The availability of parenteral antibiotics at the site of infection is usually poor, so it is crucial to maximize local antibiotic concentration using local carriers. Our work aims to describe the uses of one of these systems, Stimulan®, for the management and prevention of infections at our Institution.

Analysing the reported uses of Stimulan®, we identified two major groups: bone substitute and carrier material for local antibiotic therapy. The first group includes its application as a filler of dead spaces within bone or soft tissues resulting from traumatic events or previous surgery. The second group comprehends the use of Stimulan® for the treatment of osteomyelitis, post-traumatic septic events, periprosthetic joint infections, arthroplasty revision surgery, prevention in open fractures, surgery of the diabetic foot, oncological surgery and for all those patients susceptible to a high risk of infection.

We used Stimulan® in several complex clinical situations: in PJIs, in DAPRI procedure and both during the first and the second stage of a 2-stage revision surgery; furthermore, we started to exploit this antibiotic carrier also in prophylaxis of surgical site infections, as it happens in open fractures, and when a surgical site remediation is required, like in osteomyelitis following ORIF. Stimulan® is an extremely versatile and polyhedric material, available in the form of beads or paste, and can be mixed to a very broad range of antibiotics to better adapt to different bacteria and their antibiograms, and to surgeon's needs. These properties make it a very useful adjuvant for the management of complex cases of infection, and for their prevention, as well.

Complex spinal deformities can cause pain, neurological symptoms and imbalance (sagittal and/or coronal), severely impairing patients’ quality of life and causing disability. Their treatment has always represented a tough challenge: prior to the introduction of modern internal fixation systems, the only option was an arthrodesis to prevent worsening of the deformity. Then, the introduction of pedicle screws allowed the surgeons to perform powerful corrective manoeuvres, distributing forces over multiple levels, to which eventually associate osteotomies. In treating flexible coronal deformities, in-ternal fixation and corrective manoeuvres may be sufficient: the combination of high density pedicle screws and direct vertebral rotation revolutionized surgical treatment of scoliosis.

However, spinal osteotomies are needed for correcting complex rigid deformities; the type of osteot-omy must be chosen according to the aetiology, type and apex of the deformity. When dealing with large radius deformities, spread over multiple levels and without fusion, multiple posterior column os-teotomies such as Smith-Petersen and Ponte (asymmetric, when treating scoliosis) can be performed, dissipating the correction over many levels. Conversely, the management of a sharp, angulated de-formity that involves a few vertebral levels and/or with bony fusion, requires more aggressive 3 col-umn osteotomies such as Pedicle Subtraction Osteotomies (PSO), Bone Disc Bone Osteotomies (BDBO) or Vertebral Column Resection (VCR). Sometimes the deformity is so severe that cannot be corrected with only one osteotomy: in this scenario, multilevel osteotomies can be performed.

The computational modelling and 3D technology are finding more and more applications in the medical field. Orthopedic surgery is one of the specialties that can benefit the most from this solution. Three case reports drawn from the experience of the authors’ Orthopedic Clinic are illustraded to highlight the benefits of applying this technology.

Drawing on the extensive experience gained within the authors’ Operating Unit, three cases regarding different body segments have been selected to prove the importance of 3D technology in preoperative planning and during the surgery. A sternal transplant by allograft from a cryopreserved cadaver, the realization of a custom made implant of the glenoid component in a two-stage revision of a reverse shoulder arthroplasty, and a case of revision on a hip prosthesis with acetabular bone loss (Paprosky 3B) treated with custom system. In all cases the surgery was planned using 3D processing software and models of the affected bone segments, printed by 3D printer, and based on CT scans of the patients. The surgical implant was managed with dedicated instruments.

The use of 3D technology can improve the results of orthopedic surgery in many ways: by optimizing the outcomes of the operation as it allows a preliminary study of the bone loss and an evalutation of feasibility of the surgery, it improves the precision of the positioning of the implant, especially in the context of severe deformity and bone loss, and it reduces the operating time; by improving surgeon training; by increasing patient involvement in decision making and informed consent.

3D technology, by offering targeted and customized solutions, is a valid tool to obtain the tailored care that every patient needs and deserves, also providing the surgeon with an important help in cases of great complexity.

Introduction

Carriers of Staphylococcus aureus, both methicillin sensitive (MSSA) and methicillin resistant (MRSA), have an increased risk for health-care associated infections. Despite WHO recommendations there is currently no national screening and eradication policy for the detection of MSSA in the UK or USA. This study aimed to evaluate the effectiveness of current standard MRSA eradication therapies in the context of S. aureus decolonisation prior to joint replacement surgery.

Background and Aims

Daily senior review is of paramount importance to provide optimal clinical care and facilitate timely discharge. Also, the General Medical Council state in Good Medical Practice 2013 that “work should be recorded clearly, accurately and legibly…containing relevant clinical findings, decisions made and actions agreed”. This audit aims to evaluate whether all trauma and elective Orthopaedic patients at one unit receive a daily senior review, which is fully documented in the case-notes, and whether a Comprehensive Unit-based Safety Programme (CUSP) toolkit can better facilitate this?

Summary

Biomechanical studies comparing fixation constructs are predictable and do not relate to the significant clinical problems. We believe there is a need for more careful use of resources in the lab and better collaboration with surgeons to enhance clinical relevance.

3D printing an additive manufacturing technique, allowing for rapid prototyping in many industries. To date, medical applications have generally been within a research or industry environment, as the costs (expertise, software and equipment) have been prohibitive.

We have established a means by which 3D printing of bones can be achieved quickly, cost-effectively and accurately from standard computer tomography (CT) digital imaging and communications in medicine (DICOM) data.

CT DICOM data of a malunited forearm fracture were manipulated using open-source software (no cost) and a 3D model was produced by selective-laser-sintering. The entire process took 7 days (total cost £77). This process and the resultant model were then assessed for overall accuracy.

This sequential methodology provides ready and economical access to a technology that is valuable for preoperative templating/rehearsal in complex 3D reconstructive cases.

Drilling through bone is a complex action that requires precise motor skills of an orthopedic surgeon. In order to minimize plunging and soft tissue damage, the surgeon must halt drill progression precisely following penetration of the far cortex. The purpose of this study was to create a low-cost and easy-to-use drilling simulator to train orthopedic residents in reducing the drill plunging depth. This prospective observational study was performed in the division of orthopedic surgery of a single tertiary medical center. The participants included 13 residents and 7 orthopedic specialists. The simulator consisted of a synthetic femur bone model and ordinary modeling clay, and the training unit consisted of a disposable plastic tube (∼US$14), clamps (∼US$58) and a power drill + drill bit (standard hospital equipment). Plunging depths were measured by the simulator and compared between orthopedic specialists, the 6 “senior residents” (3+ years) and the 7 “junior residents” during a training session. Measurements were taken again 2 weeks following the training session. Initially, the plunging depths of the junior residents were significantly greater compared to those of the orthopedic specialists (7.00 mm vs 5.28 mm, respectively, p < 0.038). There was no similarly significant difference between the senior residents and the orthopedic experts ([6.33 mm vs. 5.28 mm, respectively; p = 0.18). The senior residents achieved plunging depths of 5.17 mm at the end of the training session and 4.7 mm 2 weeks later compared to 7.14 mm at the end of the training session and 6 mm 2 weeks later for the junior residents. This study demonstrated the capability of a low-cost drilling simulator as a training model for reducing the plunging depth during the drilling of bone and soft tissue among junior and senior residents.

Summary Statement

The purpose is to evaluate the effects of internet usage on new patient referral patterns to identify optimal patient recruitment and communication. Overall, social networking and internet may be an effective way for surgeons to recruit a wider patient population.

Objectives. During open orthopaedic surgery, joints may be exposed to air, potentially leading to cartilage drying and chondrocyte death, however, the long-term effects of joint drying in vivo are poorly understood. We used an animal model to investigate the subsequent effects of joint drying on cartilage and chondrocytes. Methods. The patellar groove of anaesthetised rats was exposed (sham-operated), or exposed and then subjected to laminar airflow (0.25m/s; 60 minutes) before wounds were sutured and animals recovered. Animals were monitored for up to eight weeks and then sacrificed. Cartilage and chondrocyte properties were studied by histology and confocal microscopy, respectively. Results. Joint drying caused extensive chondrocyte death within the superficial regions of cartilage. Histology of dried cartilage demonstrated a loss of surface integrity at four weeks, fibrillations at eight weeks, and an increased modified Mankin score (p < 0.001). Cartilage thickness increased (p < 0.001), whereas chondrocyte density decreased at four weeks (p < 0.001), but then increased towards sham-operated levels (p < 0.01) at eight weeks. By week eight, chondrocyte pairing/clustering and cell volume increased (p < 0.05; p < 0.001, respectively). Conclusions. These in vivo results demonstrated for the first time that as a result of laminar airflow, cartilage degeneration occurred which has characteristics similar to those seen in early osteoarthritis. Maintenance of adequate cartilage hydration during open orthopaedic surgery is therefore of paramount importance. Cite this article: Dr A. Hall. Drying of open animal joints in vivo subsequently causes cartilage degeneration. Bone Joint Res 2016;5:137–144. DOI: 10.1302/2046-3758.54.2000594

Abstract. Background. Ultrasonic cutting of bone boasts many advantages over alternatively powered surgical instruments, including but not limited to: elimination of swarf, reduced reaction forces, increased precision in cutting and reduced adjacent soft tissue damage, reduced post-operative complications such as bleeding and bone fracture, reduced healing time, reduced intra-operative noise and ease of handling. Despite ultrasonic cutting devices being well established in oral and maxillofacial surgery, applications in orthopaedic surgery are more niche and are not as well understood. The aim of this study was to investigate the cutting speed (mm/s) and cutting forces (N) of orthopaedic surgeons using a custom-designed state of the art ultrasonic cutting tool to cut fresh human bone samples. Methods. A setup based on the Robot Operating System (ROS) and AprilTag was designed to track and to record the real time position of the ultrasonic cutting tool in space. Synchronised load cell axial force readings of three separate orthopaedic surgeons during ultrasonic cutting were recorded. Each surgeon was asked to find a comfortable position that reflects as close as possible their clinical handling of a cutting instrument used in surgery, and to perform two cuts in each of three samples of human cortical bone. Bone samples were obtained following ethical approval from an institutional review board (ethics approval number: SR1342) and prior informed consent was obtained from all patients. Bone samples were extracted from the femoral neck region of three hip osteoarthritis patients. During cutting, surgeons were allowed a total cutting time of one minute and cutting was conducted using an ultrasonic tool with frequency of a 35kHz (35.7 µm peak to peak displacement amplitude) under constant irrigation using a MINIPULS® 3 Peristaltic pump (38 revolutions per minute) using Phosphate-Buffered Saline (PBS) at 25°C. From the recorded data, the average instantaneous cutting velocity was calculated and the maximum cutting force was identified. Results. All surgeons assumed a back-and-forth cutting motion, variation in the applied cutting force was observed. The average vertical cutting speed, axial cutting force and cutting depth across all surgeons and all samples was 1.64 mm/s, 1.91 N and 0.73 mm, respectively. While increasing the axial cutting force resulted in a deeper cut, overloading of the ultrasound transducer occurred when the tool advanced too quickly into the bone tissue during cutting. The exact force threshold, or the optimal speed at which the surgeon can maintain a constant force during cutting, requires further investigation. Conclusions. In this study, all surgeons cut using a back-and-forth cutting motion, with variation in the applied cutting force which may ultimately inform which clinical applications in orthopaedic engineering are most suitable for this technology. Applying too much force caused overloading of the ultrasound transducer, which is a limitation with the current cutting tool. The results from this study may facilitate the eventual uptake of ultrasonic cutting tools for application in orthopaedic surgery. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

Recently, there is ongoing evidence regarding rapid recovery after orthopaedic surgery, with advantages for the patient relative to post operative pain, complications and functional recovery. The aim of this study is to present our experience in rapid recovery for adolescent idiopathic scoliosis in the last 2 years. Retrospective study of 36 patients with adolescent idiopathic scoliosis, (age range 11 to 18 years) treated with spinal thoraco-lumbar posterior fusion with rapid post-operative recovery, compared with a similar group, treated with traditional protocol. We found a statistically significant difference in terms of length-of-stay, patient-controlled-analgesia and use of oppioid and post operative blood transfusions. There was no difference in post operative infection rate. Our experience shows better functional recovery, satisfactory controlled analgesia and reduction in costs of hospitalization with the use of ERAS protocols