Total knee arthroplasty can largely impact the functioning of a knee. To minimize the impact of surgery and increase patient satisfaction, it is believed that restoring knee stability and control of the laxity has the potential to improve surgical outcome. In that respect, it is hypothesized that a well-balanced knee restores the native knee's laxity and stability, whereas unbalanced conditions result in an increased laxity and instability. This study intends to precisely evaluate knee laxity and stability in a cadaveric model in order to improve the clinical evaluation of the knee laxity under surgical conditions. This paper provides insight in the design considerations and methodology of a novel knee simulator and the preliminary results. In a first phase, a new knee simulator has therefore been developed. This simulator allows quantifying the knee kinematics and surgical feel at the time of surgery in a laboratory environment. More specifically, full lower limb specimens can be mounted in the simulator. This overcomes the need for disarticulation at the hip and ankle, often reported in cadaveric testing. The latter is believed to potentially release the tension in the knee and should therefore be avoided. Note that in respect to surgical conditions no muscle activation is considered for this simulator. To facilitate a repeatable and unbiased evaluation of the knee kinematics, it is important that the knee simulator provides full kinematic freedom to the tested knee specimen. To obtain six degrees of freedom, a dedicated hip and ankle setup has been created (figure 1). The hip setup constrains the hip joint to a single axis hinge joint around the femoral head center. The remaining five degrees of freedom are built into the ankle setup. More specifically, the ankle setup has two translational degrees of freedom and full rotational freedom. The translational freedom is provided along the specimen's proximal-distal axis and medio-lateral axis. The rotational freedom is provided at a single point, using a ball in socket joint located along the mechanical axis of the tibia. The translation along the proximal-distal axis is thereby actively controlled by the operator, simulating heel push conditions. In addition to studying the neutral path kinematics, the presented simulator allows evaluating the laxity boundaries throughout the range of motion. Therefore, a constant internal/external torque can be applied to the tibia. Alternatively, a constant varus/valgus moment can be simulated. Second, following the design and construction of this simulator, a set of ten cadaveric knees has been tested on this simulator, both before and after TKA surgery. For the native knees, the results of these tests confirm the kinematic freedom provided to the tested knee. In addition, the laxity envelope around the neutral path can be realistically evaluated and quantified. Conclusion. Design and evaluation of new knee simulator that allows synchronous studying of the knee kinematics, contact loads and tensile forces, under neutral conditions and extreme varus/valgus moment or internal/external tibial torque

The purpose of this study was to measure the effect of the implementation of a LEAN continuous process improvement initiative on the waitlist in an ambulatory pediatric orthopaedic clinic.

LEAN is a set of principles that guide organizational thinking and form a comprehensive approach to continuous process improvement. In 2016, our health centre began its journey towards becoming a LEAN organization. The health centre's Strategy and Performance portfolio collaborated with the Orthopaedic Clinic Team to facilitate a Value Stream Analysis, which mapped the clinic process from referral to discharge from care. This informed the plan for targeted improvement events designed to identify and reduce non-value added activity, while partnering with patients and families to share their experiences with care in the clinic. Improvement events included: In-Clinic Patient Flow; Scheduling Process Review; Standardized Triage Process; Clinician Schedule; 5-S Large Cast and Sample Exam Rooms; Booking Orthopedics Clinic; and Travelling and Remote Care. During each event, solutions were identified to improve the patient experience, access, and clinic flow. These solutions have been standardized, documented, and continuously monitored to identify additional improvement opportunities. Comparison of wait-list and percentage of new patients seen within target window was performed from August 2017 to December 2018.

The LEAN initiative resulted in a 48% decrease in wait-list for new patients, which translated to an improvement from 39% to 70% of new patients seen within their target window. There was a 19% decrease in the 3400+ patient wait-list for follow-up appointments, an 85% reduction in follow-up patients waiting past their target date for an appointment, and the number of patients waiting over a year beyond their target appointment improved from over 300 patients to 0 patients. There was a 15% improvement in average length of clinic visit.

Without the addition of new resources, the implementation of a LEAN continuous process improvement initiative improved the waitlist for new patients in an ambulatory pediatric orthopaedic clinic by almost 50%. Solutions identified and implemented through the LEAN process have contributed to unprecedented improvements in access to care. In fulfilling one of the LEAN theory principles to “pursue perfection”, the paediatric orthopaedic clinic team has embraced a culture of continuous improvement and continues to use LEAN tools such as daily huddles and visual management to monitor solutions and identify gaps.

In different contemporary posterior-stabilized (PS) total knees, there are considerable variations in condylar surface radii and cam-post geometry. This is expected to result in differences in kinematics and functional outcomes in patients. The hypotheses of our study were: 1. Current PS design will show symmetric motion which is different from anatomic motion, and 2. An asymmetric PS design will produce motion closer to normal anatomic motion than symmetric designs. A special machine was constructed which could implement the ASTM standard test on constraint, by measuring the laxities. The rational for the test is to predict functional laxity ranges which will affect the kinematics in vivo. The machine set the knee at the required flexion angles and applied combinations of compressive, shear, and torque forces, to represent a range of everyday activities. The femorotibial contact points, the neutral path of motion, and the AP and internal-external laxities were used as the motion indicators. The benchmark was the motion data from anatomic knee specimens tested under the same conditions. Four contemporary PS designs with a range of geometries was selected for the tests, together with a design where the medial side was more constrained, the lateral side was less constrained, and the post was rounded. The output motions were compared between themselves, while all designs were compared with the anatomic data. The PS designs showed major differences in motion characteristics among themselves including the neutral path of motion and the AP and rotational laxities. These differences were related to the constraints of the condyles, and the cam-post designs. The four PS designs showed motion different from anatomic, including symmetric mediolateral motion, susceptibility to excessive AP medial laxity, and reduced laxity in high flexion. The asymmetric Guided Motion design alleviated some but not all of the abnormalities; in particular, while the lateral rollback with flexion and the near-constant position of the medial femoral condyle resembled anatomic behaviour, the rotational laxity was still limited in high flexion. The latter ws observed to be due to the ‘entrapment’ of the femoral condyles between the upwards posterior lip of the tibial plastic, and the posterior of the cam-post, a phenomenon seen on all designs. The conclusion of the study is that an asymmetric PS design may provide a path to achieving a closer match to anatomic kinematics. This may improve functional outcomes, and even provide a better ‘feel’ to the patient. However, there are still inherent challenges in PS design to closely achieve this goal. Other design configurations have also been formulated which could even more closely reproduce anatomic motion. However a pre-clinical testing method such as presented here, is one method for evaluation and can be used hand-in-hand with computational methods to produce an optimal design. The importance of the benchmark of the anatomic knee and the identification of the important parameters of the ASTM standard, notably the neutral path of motion and the laxity about the neutral path, are important aspects of the design methodology

INTRODUCTION:

Previous modalities such as static x-rays, MRI scans, CT scans and fluoroscopy have been used to diagnosis both soft-tissue clinical conditions and bone abnormalities. Each of these diagnostic tools has definite strengths, but each has significant weaknesses. The objective of this study is to introduce two new diagnostic, ultrasound and sound/vibration sensing, techniques that could be utilized by orthopaedic surgeons to diagnose injuries, defects and other clinical conditions that may not be detected using the previous mentioned modalities.

Background

Body Mass Index (BMI) is used to quantify generalised obesity, but does not account for variations in soft tissue distribution.

Aims. The evidence base within trauma and orthopaedics has traditionally favoured quantitative research methodologies. Qualitative research can provide unique insights which illuminate patient experiences and perceptions of care. Qualitative methods reveal the subjective narratives of patients that are not captured by quantitative data, providing a more comprehensive understanding of patient-centred care. The aim of this study is to quantify the level of qualitative research within the orthopaedic literature. Methods. A bibliometric search of journals’ online archives and multiple databases was undertaken in March 2024, to identify articles using qualitative research methods in the top 12 trauma and orthopaedic journals based on the 2023 impact factor and SCImago rating. The bibliometric search was conducted and reported in accordance with the preliminary guideline for reporting bibliometric reviews of the biomedical literature (BIBLIO). Results. Of the 7,201 papers reviewed, 136 included qualitative methods (0.1%). There was no significant difference between the journals, apart from Bone & Joint Open, which included 21 studies using qualitative methods, equalling 4% of its published articles. Conclusion. This study demonstrates that there is a very low number of qualitative research papers published within trauma and orthopaedic journals. Given the increasing focus on patient outcomes and improving the patient experience, it may be argued that there is a requirement to support both quantitative and qualitative approaches to orthopaedic research. Combining qualitative and quantitative methods may effectively address the complex and personal aspects of patients’ care, ensuring that outcomes align with patient values and enhance overall care quality

Emerging evidence suggests preoperative opioid use may increase the risk of negative outcomes following orthopedic procedures. This systematic review evaluated the impact of preoperative opioid use in patients undergoing shoulder surgery with respect to preoperative clinical outcomes, postoperative complications, and postoperative dependence on opioids. EMBASE, MEDLINE, CENTRAL, and CINAHL were searched from inception to April, 2021 for studies reporting preoperative opioid use and its effect on postoperative outcomes or opioid use. The search, data extraction and methodologic assessment were performed in duplicate for all included studies. Twenty-one studies with a total of 257,301 patients were included in the final synthesis. Of which, 17 were level III evidence. Of those, 51.5% of the patients reported pre-operative opioid use. Fourteen studies (66.7%) reported a higher likelihood of opioid use at follow-up among those used opioids preoperatively compared to preoperative opioid-naïve patients. Eight studies (38.1%) showed lower functional measurements and range of motion in opioid group compared to the non-opioid group post-operatively. Preoperative opioid use in patients undergoing shoulder surgeries is associated with lower functional scores and post-operative range of motion. Most concerning is preoperative opioid use may predict increased post-operative opioid requirements and potential for misuse in patients

Aims. We studied the outcomes following arthroscopic primary repair of bucket handle meniscus tears to determine the incidence of re-tears and the functional outcomes of these patients. Methodology. Prospective cohort study. Over a 4-year period (2016 to 2020), 35 adult patients presented with a bucket handle tear of the meniscus. Arthroscopic meniscal repair was performed using either the all inside technique or a combination of all-inside and inside-out techniques. 15 patients also underwent simultaneous arthroscopic anterior cruciate ligament reconstruction. Functional knee scores were assessed using IKDC and Lysholm scores. Results. Mean patient age at surgery was 27 years (range, 17 to 53years). Medial meniscus was torn in 20 and lateral in 15 cases. Zone of tear was white on white in 19, red on white in 9 and red on red in 7 cases. Average delay from injury to surgery was 4 months. At a mean follow-up of 4.5 years, the meniscus repair failed in 3 patients (8.5 %). Outcome following re-tear was meniscus excision. Average IKDC scores in patients with intact repair were 74.04 against 56.67 in patients with a failed repair (p< 0.0001). Similarly, Lyshlom scores were 88.96 and 67.333, respectively (p<0.0001). Conclusion. The survivorship of primary repair of bucket handle meniscus tears in our series was 91.5% at medium term follow-up. Functional outcomes were significantly poor in patients with a failed repair compared to those with an intact repair

Abstract. Introduction. The short and long-term effects of covid infection are still being explored. Following a series of joint infections noted in patients presenting to a tertiary care hospital during the COVID-19 pandemic, we explored if there was any difference in the incidence of these joint infections when compared to pre-COVID era. Aim. The aim of this study was to determine the incidence of native joint infections during COVID and pre-COVID period and compare the two groups for any differences. Methodology. Patients diagnosed with septic arthritis over the 15th months of lockdown were studied and were compared with the same period prior to Covid-19 infection. The patient characteristics, the rate of septic arthritis, the presence of recent Covid-19 infection, delay in diagnosis and the difference in the microbiology between the two groups was studied. Results. There were 36 joint infections during the COVID period in comparison to 46 joint infections during pre-COVID period. Both groups had similar mean age. Knee was the most common joint involved in both groups. About 50% (n = 18) of the joint infections during the COVID period did not grow any micro-organisms even after extended culture, which was higher in comparison to the pre-COVID group (35%, n = 16). Conclusion. The culture negative group have significantly reduced markers of infection. The was no increase in the rate of septic arthritis however there was an increase in culture negative arthritis denoting a possible outbreak of reactive arthritis in the Covid-19 period

Minimally displaced paediatric proximal humerus fractures (PHFs) can be reliably managed non-operatively, however there is considerable debate regarding the appropriate management of severely displaced PHFs, particularly in older children and adolescents with limited remodelling potential. The purpose of this study was to perform a systematic review to answer the questions: “What are the functional and quality-of-life outcomes of paediatric PHFs?” and “What factors have been associated with a poorer outcome?”. A review of Medline and EMBASE was performed on 4. th. July 2021 using search terms relevant to PHFs, surgery, non-operative management, paediatrics and outcomes. Studies including ≥10 paediatric patients with PHFs, which assessed clinical outcomes by use of an established outcome measure, were selected. The following clinical information was collected: participant characteristics, treatment, complications, and outcomes. Twelve articles were selected, including four prospective cohort studies and eight retrospective cohort studies. Favourable outcome scores were found for patients with minimally displaced fractures, and for children aged less than ten years, irrespective of treatment methodology or grade of fracture displacement. Older age at injury and higher grade of fracture displacement were reported as risk factors for a poorer patient-reported outcome score. An excellent functional outcome can be expected following non-operative management for minimally displaced paediatric PHFs. Prospective trials are required to establish a guideline for the management of severely displaced PHFs in children and adolescents according to fracture displacement and the degree of skeletal maturity

The trapeziometacarpal joint (TMCJ) is the most common hand joint affected by osteoarthritis (OA), and trapezium implant arthroplasty is a potential treatment for recalcitrant OA. This meta-analysis aimed to investigate the efficacy and safety of various trapezium implants as an interventional option for TMCJ OA. Web of Science, PubMed, Scopus, Google Scholar, and Cochrane library databases were searched for relevant studies up to May 2022. Preferred Reported Items for Systematic Review and Meta-Analysis guidelines were adhered to and registered on PROSPERO. The methodological quality was assessed by National Heart, Lung, and Blood Institute tools for observational studies and the Cochrane risk of bias tool. Subgroup analyses were performed on different replacement implants, the analysis was done via Open Meta-Analyst software and P values < 0.05 were considered statistically significant. A total of 123 studies comprising 5752 patients were included. Total joint replacement (TJR) implants demonstrate greater significant improvements in visual analogue scale pain scores postoperatively. Interposition with partial trapezial resection implants was associated with the highest grip strength and highest reduction in the Disabilities of the Arm, Shoulder, and Hand score. Revision rates were highest in TJR (12.3%), and lowest in interposition with partial trapezial resection (6.2%). Total joint replacement and interposition with partial trapezial resection implants improve pain, grip strength, and DASH scores more than other implant options. Future studies should focus on high-quality randomized clinical trials comparing different implants to accumulate higher quality evidence and more reliable conclusions

Aim. Periprosthetic joint infection (PJI) is one of the most frequent and devastating complications of total knee arthroplasty (TKA). Accurate diagnosis and proper treatment are essential to prevent functional loss and progression to systemic infection. However, the correct diagnosis of PJI is still a challenge since there is no accurate diagnostic method and the existing diagnostic criteria are based on serological, histological and microbiological tests that are imprecise and time-consuming. Recently, it was demonstrated that cell-free DNA is increased in the synovial fluid of patients with PJI. Therefore, this study aims to evaluate a new point-of-care methodology for quantifying free DNA in synovial fluid. Method. A prospective study was carried out with patients undergoing TKA revision surgery, from whom it was possible to collect synovial fluid (SF) during the surgical procedure. Cell-free DNA quantification was performed directly from the SF, using a portable fluorimeter. Sensitivity, specificity and receiver operating characteristic (ROC) curve were calculated. Results. Fifty-four patients were included in the study, of which 25 were diagnosed with PJI. Cell-free DNA levels measured immediately after collection were increased in the synovial fluid of patients with PJI (26.3 ± 14.8) in comparison with the uninfected group (4.6 ng/ml ± 3.8, p< 0.0001). The area under the receiver operating characteristic curve (AUC ROC) was 0.981 (95% CI 0.914 to 0.999). Conclusions. From the results presented, we can conclude that the quantification of free DNA with a portable fluorimeter proved to be a test with high sensitivity and specificity for the diagnosis of PJI

Introduction. Various biomaterials and bone graft substitute technologies for use in osteomyelitis treatment are currently used in clinal practice. They vary in mode of action (with or without antibiotics) and clinical application (one-stage or two-stage surgery). This systematic review aims to compare the clinical evidence of different synthetic antimicrobial bone graft substitutes and antibiotic-loaded carriers in eradicating infection and clinical outcome in patients with chronic osteomyelitis. Methods. Systematic review according to PRISMA statement on publications 2002-2023. MESH terms: osteomyelitis and bone substitutes. FREE terms: chronic osteomyelitis, bone infection. A standardized data extraction form was be used to extract data from the included papers. Results. Publications with increased methodological quality and clinical evidence for biomaterials in osteomyelitis treatment were published in the last decades. High 85-95% eradication rates of osteomyelitis were observed for various resorbable Ca-P and/or Ca-S biomaterials combined with antibiotics and S53P4 bioactive glass. Level of evidence varies significantly between products. Antibiotic pharmacokinetic release profiles vary between resorbable Ca-P and/or Ca-S biomaterials. Conclusion. Given the high 85-95% eradication rates of osteomyelitis by various resorbable Ca-P and/or Ca-S biomaterials combined with antibiotics and S53P4 bioactive glass, one-stage treatment is preferred. Surgeons should be aware of variations in mechanical properties and antibiotic pharmacokinetic release profiles between Ca-P and CA-s products. Mechanical, biological and antimicrobial properties of bioactive glass are formulation dependent. Currently, only S53P4 bioactive glass has proven antimicrobial properties. Based on this systematic review antibiotic loaded fleeces should be used with caution and restraint

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

Introduction. Perception of ACL injury prevention programs amongst professional netball players and coaches has not been studied. We investigated (1) level of awareness and experience of ACL injury prevention programs; (2) use of ACL injury prevention programs; and (3) barriers to implementing ACL injury prevention program in netball. Methodology. Female netball players representing Welsh senior and under-21 teams and elite and amateur coaches were invited electronically to this web-based study between 1st May–31st July 2021. Information on ACL injury susceptibility and seriousness, knowledge, experience, and implementation of ACL injury prevention programs were ascertained. Results. Twenty-eight players (77.8%) and 29 coaches (13.2%) completed the questionnaire. Seventeen (60.7%) players and 15 (51.7%) coaches reported female athletes were at greater risk for sustaining ACL injuries. Over 90% of respondents identified netball as high-risk, whilst 89% of players and 76% of coaches reported these injuries to be preventable. Two (7.1%) players and 6 (20.7%) coaches utilised ACL injury prevention programs with lack of time and engagement from coaches and players identified. Majority of respondents indicated that their club has neither promoted, advocated nor demonstrated exercises for ACL injury prevention. Over 90% of respondents would utilise such programs if it minimised players risk with appropriate training and information. Conclusion. Study highlights limited knowledge of female athletes’ increased susceptibility of ACL injuries with lack of communication and education of ACL injury prevention programs between sporting associations, coaches and players. Results demonstrate willingness of players and coaches to implement ACL injury prevention programs in Welsh netball

Surfing has rapidly grown in popularity as the sport made its debut at the Tokyo 2020 Olympic Games. Surfing injuries are becoming more relevant with the globalisation and increasing risks of the sport, but despite this, little is known about surfing injuries or prevention strategies in either the competitive or recreational surfer. We reviewed the literature for the incidence, anatomical distribution, type and underlying mechanism of acute and overuse injuries, and discuss current preventative measures. Four online databases, including MEDLINE, PubMed, EMBASE and Cochrane Library were searched from inception to March 2020. This review finds that skin injuries represent the highest proportion of total injuries. Acute injuries most frequently affect the head, neck and face, followed by the lower limbs. Being struck by one's own board is the most common mechanism of injury. Surfers are injured at a frequency of 0.30–6.60 injuries per 1000 hours of surfing. Most prior studies are limited by small sample sizes, poor data collection methodology and geographical constraints. The scientific literature on surfing injuries under-represents overuse musculoskeletal injuries and the efficacy of prevention strategies for surfing-related overuse musculoskeletal injuries has not been studied. Injuries to the head and neck pose greater risks to a surfer's morbidity and mortality, yet there is no consensus on the management protocol of spinal injuries that occur in open water. Non-contact acute ligament injuries have increased as surfing manoeuvres have become more acrobatic, and overuse musculoskeletal injuries are highly correlated with paddling. Further research is needed to establish preventative measures for both acute and overuse surfing injuries and to ensure the increasing popularity of surfing is met with an improved understanding of sport risks and safety. Specifically, we recommend research be prioritised regarding the efficacy of training programmes to prevent surfing-related overuse musculoskeletal injuries

Over half of postpartum women experience pelvic ring or hip pain, with multiple anatomic locations involved. The sacroiliac joints, pubic symphysis, lumbar spine and pelvic girdle are all well documented pain generators. However, despite the prevalence of postpartum hip pain, there is a paucity of literature regarding underlying soft tissue intra-articular etiologies. The purpose of this systematic review is to document and assess the available evidence regarding underlying intra-articular soft tissue etiologies of peri- and postpartum hip pain. Three online databases (Embase, PubMed and Ovid [MEDLINE]) were searched from database inception until April 11, 2021. The inclusion criteria were English language studies, human studies, and those regarding symptomatic labral pathology in the peri- or postpartum period. Exclusion criteria were animal studies, commentaries, book chapters, review articles and technical studies. All titles, relevant abstracts and full-text articles were screened by two reviewers independently. Descriptive characteristics including the study design, sample size, sex ratio, mean age, clinical and radiographic findings, pathology, subsequent management and outcomes were documented. The methodological quality of the included studies was assessed using the Methodological Index for Non-Randomized Studies (MINORS) instrument. The initial search identified 2472 studies. A systemic screening and assessment of eligibility identified 5 articles that satisfied the inclusion criteria. Twenty-two females were included. Twenty patients presented with labral pathology that necessitated hip arthroscopy with labral debridement or repair with or without acetabuloplasty and/or femoroplasty. One patient presented with an incidental labral tear in the context of osteitis condensans illi. One patient presented with post-traumatic osteoarthritis necessitating a hip replacement. The mean MINORS score of these 5 non-comparative studies was 2.8 (range 0-7) demonstrating a very low quality of evidence. The contribution of intra-articular soft tissue injury is a documented, albeit sparse, etiology contributing to peri- and postpartum hip pain. Further research to better delineate the prevalence, mechanism of injury, natural history and management options for women suffering from these pathologies at an already challenging time is necessary to advance the care of these patients

The aim of this study was to determine the incidence, annual trend, perioperative outcomes, and identify risk factors of early-onset (≤ 90 days) deep surgical site infection (SSI) following primary total knee arthroplasty (TKA) for osteoarthritis. Risk factors for early-onset deep SSI were assessed. We performed a retrospective population-based cohort study using prospectively collected patient-level data from several provincial administrative data repositories between January 2013, and March 2020. The diagnosis of early-onset deep SSI was based on published Centre for Disease Control/National Healthcare Safety Network (CDC/NHSN) definitions. The Mann-Kendall Trend Test was used to detect monotonic trends in early-onset deep SSI rates over time. The effects of various patient and surgical risk factors for early-onset deep SSI were analyzed using multiple logistic regression. Secondary outcomes were 90-day mortality and 90-day readmission. A total of 20,580 patients underwent primary TKA for osteoarthritis. Forty patients had a confirmed deep SSI within 90-days of surgery representing a cumulative incidence of 0.19%. The annual infection rate did not change over the 7-year study period (p = 0.879). Risk factors associated with early-onset deep SSI included blood transfusions (OR, 3.93 [95% CI 1.34-9.20]; p=0.004), drug or alcohol abuse (OR, 4.91 [95% CI 1.85-10.93]; p<0.001), and surgeon volume less than 30 TKA per year (OR, 4.45 [1.07-12.43]; p=0.013). Early-onset deep SSI was not associated with 90-days mortality (OR, 11.68 [0.09-90-58]; p=0.217), but was associated with an increased chance of 90-day readmission (OR, 50.78 [26.47-102.02]; p<0.001). This study establishes a reliable baseline infection rate for early-onset deep SSI after TKA for osteoarthritis through the use of a robust methodological process. Several risk factors for early-onset deep SSI are potentially modifiable or can be optimized prior to surgery and be effective in reducing the incidence of early-onset SSI. This could guide the formulation of provincial screening programs and identify patients at high risk for SSI

Background. Stemless prostheses are recognized to be an effective solution for anatomic total shoulder arthroplasty (TSA) while providing bone preservation and shortest operating time. Reverse shoulder arthroplasty (RSA) with stemless has not showed the same effectiveness, as clinical and biomechanical performances strongly depend on the design. The main concern is related to stability and bone response due to the changed biomechanical conditions; few studies have analyzed these effects in anatomic designs through Finite Element Analysis (FEA), however there is currently no study analyzing the reverse configuration. Additionally, most of the studies do not consider the effect of changing the neck-shaft angle (NSA) resection of the humerus nor the proper assignment of spatial bone properties to the bone models used in the simulations. The aim of this FEA study is to analyze bone response and primary stability of the SMR Stemless prosthesis in reverse with two different NSA cuts and two different reverse angled liners, in bone models with properties assigned using a quantitative computed tomography (QCT) methodology. Methods. Sixteen fresh-frozen cadaveric humeri were modelled using the QCT-based finite element methodology. The humeri were CT-scanned with a hydroxyapatite phantom to allow spatial bone properties assignment [Fig. 1]. Two implanted SMR stemless reverse configurations were considered for each humerus: a 150°-NSA cut with a 0° liner and a 135°-NSA cut with a 7° sloped liner [Fig. 2]. A 105° abduction loading condition was simulated on both the implanted reverse models and the intact (anatomic) humerus; load components were derived from previous dynamic biomechanical simulations on RSA implants for the implanted stemless models and from the OrthoLoad database for the intact humeri. The postoperative bone volume expected to resorb or remodel [Fig. 3a] in the implanted humeri were compared with their intact models in sixteen metaphyseal regions of interest (four 5-mm thick layers parallel to the resection and four anatomical quadrants) by means of a three-way repeated measures ANOVA followed by post hoc tests with Bonferroni correction. In order to evaluate primary stability, micromotions at the bone-Trabecular Titanium interface [Fig. 3b] were compared between the two configurations using a Wilcoxon matched-pairs signed-rank test. The significance level α was set to 0.05. Results. With the exception of the most proximal layer (0.0 – 5.0 mm), the 150°-NSA configuration showed overall a statistically significant lower bone volume expected to resorb (p = 0.011). In terms of bone remodelling, the 150°-NSA configuration had again a better response, but fewer statistically significant differences were found. Regarding micromotions, there was a median decrease (Mdn = 3.2 μm) for the 135°-NSA configuration (Mdn = 40.3 μm) with respect to the 150°-NSA configuration (Mdn = 43.5 μm) but this difference was non-significant (p = 0.464). Conclusions. For the analyzed SMR Stemless configurations, these results suggest a reduction in the risk of bone resorption when a 0° liner is implanted with the humerus cut at 150°. The used QCT-based methodology will allow further investigation, as this study was limited to one single design and load case. For any figures or tables, please contact the authors directly

Knee arthroscopy with debridement is commonly performed to treat osteoarthritis and degenerative meniscal tears in older adults; however robust evidence does not support sustained benefit from this procedure. Current Canadian guidelines advise against its use as first line treatment. Characterizing the use of this low value procedure will facilitate efforts to maximize quality of care, minimize harm and decrease healthcare costs. We sought to understand:. 1). the volume and variations of arthroscopic knee debridement across Canada. 2). The costs associated with potentially unnecessary arthroscopy. 3). The characteristics of surgeons performing knee arthroscopy in older adults. Data were derived from National Ambulatory Care Reporting System (NACRS), the Discharge Abstract Database (DAD) and the National Physician Database for years 2011-12 to 2019-20. The study included all elective knee arthroscopies (CCI codes 1.VG.80.DA,1.VG.80.FY and 1.VG.87.DA) performed in day surgery and acute care settings in 9 provinces and 3 territories of Canada. Quebec was not included in the analysis due to different reporting methods. We set a threshold of 60 years of age at which it would be highly unlikely that a patient would undergo arthroscopy to treat anything other than osteoarthritis or degenerative meniscal tear. Trends at national and provincial levels were analyzed using regression. Costs were estimated separately using the 2020 case mix groups (CMG) and comprehensive ambulatory care classification system (CACS) methodologies. Surgeons were classified by decade of graduation from medical school (1989 and prior, 1990-99, 2000-09 and 2010+) and categorized based on the proportion of their patient population who were above (“high proportion inappropriate”) or below (“low proportion inappropriate”) the overall national proportion of ≥ 60 years of age. The number of knee arthroscopies decreased by 37% (42,785 in 2011-12 to 27,034 in 2019-20) overall and 39% (11,103 in 2011-12 to 6,772 in 2019-20) in those 60 years and older (p 25% of patients 60 years and older. Fifty four percent of surgeons who graduated prior to 1989 were considered high proportion inappropriate, whereas only 30.1% of surgeons who graduated in 2010 or later were considered high proportion inappropriate (p < 0 .0001). Knee arthroscopy continues to be a common procedure in patients over 60 despite strong evidence for lack of benefit. Lower rates in this population in some provinces are encouraging for potential opportunity for improvement. Efforts at practice change should be targeted at surgeons in practice the longest. Canada spends over $12,000,000 per year on this procedure, decreasing its use could allow these resources to be directed to other areas of orthopaedics that provide higher value care