'The unexpected journey': a qualitative interview study exploring patient and health professionals experiences of participating in the knee arthroplasty versus joint distraction study (KARDS).

OBJECTIVE: The aim of the knee arthroplasty versus joint distraction (KARDS) randomised trial was to investigate whether knee joint distraction (KJD) is non-inferior to knee arthroplasty, also known as knee replacement (KR). Here we report the findings from qualitative interviews that were part of the planned KARDS process evaluation. DESIGN AND METHODS: Semi-structured qualitative interviews with staff and participants in secondary care. Data were analysed using thematic content analysis. FINDINGS: We were unable to complete the full-planned KARDS process evaluation as recruitment to the trial was closed early but key common themes emerged.Eleven members of staff were interviewed from two KARDS sites (eight initial interviews just after site opening and three follow-up interviews at 12 months). Eleven KARDS participants (six KR and five KJD) were interviewed. One overarching theme emerged: 'An unexpected journey'. This incorporated subthemes including 'an important research question', 'a roller coaster ride', 'lessons learnt', 'managing expectations' and 'a slow recovery'. These encapsulate experiences of both staff and participants. CONCLUSION: The information that we were able to collect highlights that providing adequate and comprehensive information about all aspects of treatment including estimated timelines of recovery are essential in clinical trials of novel interventions. Incorporating a comprehensive rehabilitation package following KJD was a key learning. Process evaluations in these complex trials are essential to determine issues as early as possible so appropriate changes can be made to ensure participants have a smooth journey through the trial experience. TRIAL REGISTRATION NUMBER: ISRCTN14879004.

Research priorities of members of the British Association for Surgery of the Knee.

Aims: This study aims to identify the top unanswered research priorities in the field of knee surgery using consensus-based methodology. Methods: Initial research questions were generated using an online survey sent to all 680 members of the British Association for Surgery of the Knee (BASK). Duplicates were removed and a longlist was generated from this scoping exercise by a panel of 13 experts from across the UK who provided oversight of the process. A modified Delphi process was used to refine the questions and determine a final list. To rank the final list of questions, each question was scored between one (low importance) and ten (high importance) in order to produce the final list. Results: This consensus exercise took place between December 2020 and April 2022. A total of 286 clinicians from the BASK membership provided input for the initial scoping exercise, which generated a list of 105 distinct research questions. Following review and prioritization, a longlist of 51 questions was sent out for two rounds of the Delphi process. A total of 42 clinicians responded to the first round and 24 responded to the second round. A final list of 24 research questions was then ranked by 36 clinicians. The topics included arthroplasty, infection, meniscus, osteotomy, patellofemoral, cartilage, and ligament pathologies. The management of early osteoarthritis was the highest-ranking question. Conclusion: A Delphi exercise involving the BASK membership has identified the future research priorities in knee surgery. This list of questions will allow clinicians, researchers, and funders to collaborate in order to deliver high-quality research in knee surgery and further advance the care provided to patients with knee pathology.

How Do Cartilage Lubrication Mechanisms Fail in Osteoarthritis? A Comprehensive Review.

Cartilage degeneration is a characteristic of osteoarthritis (OA), which is often observed in aging populations. This degeneration is due to the breakdown of articular cartilage (AC) mechanical and tribological properties primarily attributed to lubrication failure. Understanding the reasons behind these failures and identifying potential solutions could have significant economic and societal implications, ultimately enhancing quality of life. This review provides an overview of developments in the field of AC, focusing on its mechanical and tribological properties. The emphasis is on the role of lubrication in degraded AC, offering insights into its structure and function relationship. Further, it explores the fundamental connection between AC mechano-tribological properties and the advancement of its degradation and puts forth recommendations for strategies to boost its lubrication efficiency.

PERI-operative biologic DMARD management: Stoppage or COntinuation during orthoPaEdic operations (the PERISCOPE trial) - a study protocol for a pragmatic, UK multicentre, superiority randomised controlled trial with an internal pilot, economic evaluation and nested qualitative study.

INTRODUCTION: Biological disease-modifying antirheumatic drugs (bDMARDs) have revolutionised the treatment of inflammatory arthritis (IA). However, many people with IA still require planned orthopaedic surgery to reduce pain and improve function. Currently, bDMARDs are withheld during the perioperative period due to potential infection risk. However, this predisposes patients to IA flares and loss of disease control. The question of whether to stop or continue bDMARDs in the perioperative period has not been adequately addressed in a randomised controlled trial (RCT). METHODS AND ANALYSIS: PERISCOPE is a multicentre, superiority, pragmatic RCT investigating the stoppage or continuation of bDMARDs. Participants will be assigned 1:1 to either stop or continue their bDMARDs during the perioperative period. We aim to recruit 394 adult participants with IA. Potential participants will be identified in secondary care hospitals in the UK, screened by a delegated clinician. If eligible and consenting, baseline data will be collected and randomisation completed. The primary outcome will be the self-reported PROMIS-29 (Patient Reported Outcome Measurement Information System) over the first 12 weeks postsurgery. Secondary outcome measures are as follows: PROMIS - Health Assessment Questionnaire (PROMIS-HAQ), EQ-5D-5L, Disease activity: generic global Numeric Rating Scale (patient and clinician), Self-Administered Patient Satisfaction scale, Health care resource use and costs, Medication use, Surgical site infection, delayed wound healing, Adverse events (including systemic infections) and disease-specific outcomes (according to IA diagnosis). The costs associated with stopping and continuing bDMARDs will be assessed. A qualitative study will explore the patients' and clinicians' acceptability and experience of continuation/stoppage of bDMARDs in the perioperative period and the impact postoperatively. ETHICS AND DISSEMINATION: Ethical approval for this study was received from the West of Scotland Research Ethics Committee on 25 April 2023 (REC Ref: 23/WS/0049). The findings from PERISCOPE will be submitted to peer-reviewed journals and feed directly into practice guidelines for the use of bDMARDs in the perioperative period. TRIAL REGISTRATION NUMBER: ISRCTN17691638.

Brushing Up on Cartilage Lubrication: Polyelectrolyte-Enhanced Tribological Rehydration.

This study presents new insights into the potential role of polyelectrolyte interfaces in regulating low friction and interstitial fluid pressurization of cartilage. Polymer brushes composed of hydrophilic 3-sulfopropyl methacrylate potassium salt (SPMK) tethered to a PEEK substrate (SPMK-g-PEEK) are a compelling biomimetic solution for interfacing with cartilage, inspired by the natural lubricating biopolyelectrolyte constituents of synovial fluid. These SPMK-g-PEEK surfaces exhibit a hydrated compliant layer approximately 5 µm thick, demonstrating the ability to maintain low friction coefficients (µ ∼ 0.01) across a wide speed range (0.1-200 mm/s) under physiological loads (0.75-1.2 MPa). A novel polyelectrolyte-enhanced tribological rehydration mechanism is elucidated, capable of recovering up to ∼12% cartilage strain and subsequently facilitating cartilage interstitial fluid recovery, under loads ranging from 0.25 to 2.21 MPa. This is attributed to the combined effects of fluid confinement within the contact gap and the enhanced elastohydrodynamic behavior of polymer brushes. Contrary to conventional theories that emphasize interstitial fluid pressurization in regulating cartilage lubrication, this work demonstrates that SPMK-g-PEEK's frictional behavior with cartilage is independent of these factors and provides unabating aqueous lubrication. Polyelectrolyte-enhanced tribological rehydration can occur within a static contact area and operates independently of known mechanisms of cartilage interstitial fluid recovery established for converging or migrating cartilage contacts. These findings challenge existing paradigms, proposing a novel polyelectrolyte-cartilage tribological mechanism not exclusively reliant on interstitial fluid pressurization or cartilage contact geometry. The implications of this research extend to a broader understanding of synovial joint lubrication, offering insights into the development of joint replacement materials that more accurately replicate the natural functionality of cartilage.

Dual-Mobility Acetabular Components in Primary Total Hip Arthroplasty Do Not Increase the Risk of Complication Compared to Conventional Articulations: A Matched Cohort Comparative Analysis.

Background: A recent National Joint Registry report suggests a higher local complication risk for dual-mobility (DM) total hip arthroplasty (THA) compared to conventional articulation THA. This report may be subject to data heterogeneity with multiple confounders. Controlling for these factors by matching demographic characteristics may give different results. We aim to compare 2-year local complication rates between matched DM and conventional THAs in primary hip osteoarthritis. Methods: Data were collected for consecutive primary THAs undertaken via a posterior approach. The conventional articulation and DM cohorts were matched 3:1 for age, gender, American Society of Anesthesiology grade, body mass index, and operative time using a propensity score and nearest neighbor matching method. Outcome measures were 2-year local complication rates, reoperation rates, systemic complication rates, and mortality rates. Demographic and outcome data were compared, and cumulative survival rates (%) were assessed using Kaplan-Meier methodology with a 2-year local complication as the endpoint. Statistical significance was set at P < .05. Results: Four hundred twelve THAs were included: 309 conventional and 103 DM articulations. There were no statistically significant differences between DM and conventional articulation THAs for local complications (7 [6.8%] vs 23 [7.4%], P = .820), reoperations (3 [2.9%] vs 4 [1.3%], P = .374), systemic complications (3 [2.9%] vs 4 [1.3%], P = .374), or 90-day mortality (1 [1%] vs 2 [0.6%], P = 1.000). Kaplan-Meier survival analysis demonstrated similar 2-year survival rates for conventional THAs compared to DM THAs (93.3% [standard error, 0.014] vs 91.9% [standard error, 0.031], P = .906). Conclusions: This matched study shows that there is no difference in local complication rates between DM and conventional THA articulations.

Characterisation and Expression of Osteogenic and Periodontal Markers of Bone Marrow Mesenchymal Stem Cells (BM-MSCs) from Diabetic Knee Joints.

Type 2 diabetes mellitus (T2DM) represents a significant health problem globally and is linked to a number of complications such as cardiovascular disease, bone fragility and periodontitis. Autologous bone marrow mesenchymal stem cells (BM-MSCs) are a promising therapeutic approach for bone and periodontal regeneration; however, the effect of T2DM on the expression of osteogenic and periodontal markers in BM-MSCs is not fully established. Furthermore, the effect of the presence of comorbidities such as diabetes and osteoarthritis on BM-MSCs is also yet to be investigated. In the present study, BM-MSCs were isolated from osteoarthritic knee joints of diabetic and nondiabetic donors. Both cell groups were compared for their clonogenicity, proliferation rates, MSC enumeration and expression of surface markers. Formation of calcified deposits and expression of osteogenic and periodontal markers were assessed after 1, 2 and 3 weeks of basal and osteogenic culture. Diabetic and nondiabetic BM-MSCs showed similar clonogenic and growth potentials along with comparable numbers of MSCs. However, diabetic BM-MSCs displayed lower expression of periostin (POSTN) and cementum protein 1 (CEMP-1) at Wk3 osteogenic and Wk1 basal cultures, respectively. BM-MSCs from T2DM patients might be suitable candidates for stem cell-based therapeutics. However, further investigations into these cells' behaviours in vitro and in vivo under inflammatory environments and hyperglycaemic conditions are still required.

Initiating versus delaying treatment-dose anticoagulation in suspected venous thromboembolism (VTE) in post-operative hip and knee arthroplasty patients: Outcomes and risks.

Background: Hip and knee arthroplasty is a risk factor for venous thromboembolism (VTE). Initiation of treatment-dose anticoagulation in the post-operative period in suspected cases prior to confirmed diagnosis involves balancing increased bleeding risk to VTE-associated morbidity. Methods: A single-centre retrospective cohort study was undertaken comparing outcomes of empirical treatment of suspected VTE in post-operative elective lower-limb arthroplasty patients as opposed to delaying treatment until diagnosis is confirmed. All patients undergoing ultrasonography (US) or CT-pulmonary-angiogram (CTPA) for suspected VTE following elective total hip arthroplasty (THA) or total knee arthroplasty (TKA) between 05/05/17 and 19/07/21 were identified. Primary outcomes were surgical site infection (SSI), readmission, and other wound problems within 30-days of surgery. Results: 107 patients were included for analysis. 93 patients had suspected deep venous thrombosis (DVT), 21 had suspected pulmonary embolism (PE), and 7 were investigated for both DVT and PE. Empirical treatment-dose anticoagulation was initiated in 4 patients with suspected pulmonary embolism (PE) prior to CTPA, and 34 patients with suspected deep venous thrombosis (DVT) prior to US. No significant differences were noted in 30-day readmission rate ([DVT: 12 % vs 23 %, p = 0.41], [PE: 50 % vs 33 %, p = 1.00]), SSI rate ([DVT: 6 % vs 3 %, p = 1.00], [PE: 0 % vs 11 %, p = 1.00]) or other wound complication rate ([DVT: 3 % vs 3 %, p = 1.00), [PE 0 % vs 11 %, p = 1.00]) between empirically and non-empirically treated groups respectively. Conclusion: Empirical initiation of therapeutic anticoagulation in post-operative lower limb arthroplasty patients with suspected VTE appears to be safe practice prior to a definitive diagnosis.

In Vitro Osteogenesis Study of Shell Nacre Cement with Older and Young Donor Bone Marrow Mesenchymal Stem/Stromal Cells.

Bone void-filling cements are one of the preferred materials for managing irregular bone voids, particularly in the geriatric population who undergo many orthopedic surgeries. However, bone marrow mesenchymal stem/stromal cells (BM-MSCs) of older-age donors often exhibit reduced osteogenic capacity. Hence, it is crucial to evaluate candidate bone substitute materials with BM-MSCs from the geriatric population to determine the true osteogenic potential, thus simulating the clinical situation. With this concept, we investigated the osteogenic potential of shell nacre cement (SNC), a bone void-filling cement based on shell nacre powder and ladder-structured siloxane methacrylate, using older donor BM-MSCs (age > 55 years) and young donor BM-MSCs (age < 30 years). Direct and indirect cytotoxicity studies conducted with human BM-MSCs confirmed the non-cytotoxic nature of SNC. The standard colony-forming unit-fibroblast (CFU-F) assay and population doubling (PD) time assays revealed a significant reduction in the proliferation potential (p < 0.0001, p < 0.05) in older donor BM-MSCs compared to young donor BM-MSCs. Correspondingly, older donor BM-MSCs contained higher proportions of senescent, ß-galactosidase (SA-ß gal)-positive cells (nearly 2-fold, p < 0.001). In contrast, the proliferation capacity of older donor BM-MSCs, measured as the area density of CellTrackerTM green positive cells, was similar to that of young donor BM-MSCs following a 7-day culture on SNC. Furthermore, after 14 days of osteoinduction on SNC, scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS) showed that the amount of calcium and phosphorus deposited by young and older donor BM-MSCs on SNC was comparable. A similar trend was observed in the expression of the osteogenesis-related genes BMP2, RUNX2, ALP, COL1A1, OMD and SPARC. Overall, the results of this study indicated that SNC would be a promising candidate for managing bone voids in all age groups.

Risk factors for periprosthetic femoral fracture risk around a cemented polished taper-slip stem using an osteoporotic composite bone model.

This biomechanical study aimed to determine if variations in stem material, stem geometry, stem offset and cement viscosity affect mechanical resistance to postoperative periprosthetic fracture (PFF) after hip arthroplasty with a commonly used cemented polished taper-slip (PTS) stem (CPT, Zimmer Biomet) in a novel osteoporotic composite femoral bone model. Thirty-six osteoporotic composite femoral models were tested using a standardised in-vitro loading technique to simulate a typical PFF. Outcome measures were torque to failure (N), fracture energy (N/m2) and rotation to failure (°). Comparisons were made by stem material (cobalt chrome vs stainless steel), stem geometry (CPT stem vs Exeter stem), stem offset (standard offset vs extra extended offset) and cement viscosity (high viscosity vs low viscosity). Statistical comparisons were carried out with significance set at p < 0.05. All tested samples produced clinically representative fracture patterns with varying degrees of bone and cement comminution. There was no statistically significant difference in torque to failure, fracture energy or rotation to failure between any of the compared variables (all p > 0.05). This is the first biomechanical study on mechanical resistance to PFF using osteoporotic composite bone models. For the CPT stem, it confirms that stem material, stem offset, stem geometry and cement viscosity do not affect mechanical resistance to PFF in an osteoporotic bone model.

Soluble low affinity nerve growth factor receptor (sLNGFR) may regulate pain in knee osteoarthritis.

OBJECTIVES: Nerve growth factor ß (ß-NGF) is a protein which is important to the development of neurons particularly those involved in the transmission of pain and is central to the experience of pain in osteoarthritis (OA). Direct NGF antagonism has been shown to reduce OA pain but is associated with rapidly progressive OA. The aim of the study is to investigate the ability of soluble neurotrophin receptors in the NGF pathway to modulate pain in OA. METHODS: Synovial fluid (SF) was obtained from the knee joints of 43 subjects who underwent total knee arthroplasty. Visual analogue scale (VAS) pain scores were obtained prior to surgery. Customised-automated-ELISAs and commercial-ELISAs and LEGENDplex™ were used to measure soluble low-affinity nerve growth factor (LNGFR), soluble tropomyosin receptor kinase (TrkA), proNGF, ß-NGF, other neurotrophins (NT) and cytokines including inflammatory marker TNF-α. RESULTS: The VAS score positively correlated with ß-NGF (r=0.34) and there was positive association trend with neurotrophin-3 (NT-3), BDNF and negative association trend with ProNGF. sLNGFR positively correlated with VAS (r=0.33). The ß-NGF/soluble TrkA ratio showed a strong positive correlation with VAS (r=0.80). In contrast, there was no correlation between pain and the ß-NGF/sLNGFR ratio (r=-0.08). TNF-α positively correlated with ß-NGF (r=0.83), NT-3 (r=0.66), and brain-derived neurotrophic factor (BDNF) (r=0.50) and negatively with ProNGF (r= -0.74) and positively correlated with both soluble TrkA (r=0.62), sLNGFR (r=0.26). CONCLUSIONS: This study suggests that endogenous or cleaved sLNGFR, but not soluble TrkA may participate in OA pain modulation thus supporting further research into soluble LNGFR as a therapeutic target in OA.

Withholding of Hormone Replacement Therapy Prior to Total Joint Arthroplasty Surgery to Reduce the Risk of Postoperative Thromboembolic Events: Is It Justified?-A Systematic Review of Clinical Practice Guidelines.

BACKGROUND: Hormone replacement therapy (HRT), menopausal hormone therapy (MHT), and estrogen-containing medications are frequently withheld before elective lower limb arthroplasty, based on a perceived risk of venous thromboembolism (VTE). However, evidence linking HRT, MHT, and an increased VTE risk is equivocal. This systematic review evaluated the concordance of international clinical practice guidelines (CPGs) on the withholding of HRT or MHT. METHODS: The PubMed, Google Scholar, Cochrane, and Ovid databases were searched for CPGs for the preoperative, perioperative, and postoperative management of patients on HRT and MHT undergoing elective lower limb arthroplasty. This was supplemented by an internet search. There were 7 international CPGs in English, from Europe and North America, published between January 2000 and February 2023 reviewed against the Appraisal of Guidelines for Research & Evaluation Instrument (AGREE-II) criteria, in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist. RESULTS: The guidelines reviewed revealed a mixed picture on HRT or MHT withdrawal and use in arthroplasty, with some featuring detailed advice on the preoperative and postoperative management of HRT or MHT (Scottish Intercollegiate Guidelines Network), while others featured no guidance (American College of Chest Physicians). The evidence referenced in these guidelines highlighted studies showing HRT or MHT to play a limited role in increasing VTE risk, with most studies from the 1990s and 2000s. CONCLUSIONS: Based on current evidence, non-estrogen-containing transdermal HRT or MHT should not be withheld in patients undergoing elective joint arthroplasty, though further evidence is required to justify withholding estrogen-containing forms.

Systematic Review and Meta-Analysis of Studies Comparing the Rate of Post-operative Periprosthetic Fracture Following Hip Arthroplasty With a Polished Taper Slip versus Composite Beam Stem.

BACKGROUND: We compared the incidence of postoperative periprosthetic femoral fractures (POPFF) following hip arthroplasty with either a cemented polished taper slip (PTS) stem or a cemented composite beam (CB) stem in comparative studies. METHODS: A systematic review of comparative studies, written in English and published in peer-reviewed journals since the year 2000, was conducted. Study quality was assessed using the Newcastle-Ottawa scale.The overall study qualities were good. There were 913,021 patients from 18 cohorts included in the meta-analysis. There were 294,540 patients who received a CB stem and 618,481 received a PTS stem. Cohorts were classified as high- or low-risk for POPFF based on patient risk factors. A metanalysis was performed using a random effects model, and the relative incidence with 95% confidence intervals (CIs) was reported. RESULTS: The patients at low risk of POPFF had an incidence rate ratio of 3.14 (CI: 2.48, 3.98) for the PTS group versus the CB group. Whereas, the patients at high risk of POPFF had an incidence rate ratio of 9.87 (CI: 3.63, 26.80) for the PTS group versus the CB group. CONCLUSIONS: The risk of POPFF is lower when hip arthroplasty was performed using a CB stem versus a PTS stem. This protective effect was greatest in patients who had a higher risk of POPFF. Surgeons should consider the effect of cemented stem choice on the risk of subsequent periprosthetic femur fracture, particularly in frail or elderly patients who are at a higher risk of postoperative periprosthetic femoral fracture.

Cemented femoral stem design and postoperative periprosthetic fracture risk following total hip arthroplasty.

Polished taper-slip (PTS) cemented stems have an excellent clinical track record and are the most common stem type used in primary total hip arthroplasty (THA) in the UK. Due to low rates of aseptic loosening, they have largely replaced more traditional composite beam (CB) cemented stems. However, there is now emerging evidence from multiple joint registries that PTS stems are associated with higher rates of postoperative periprosthetic femoral fracture (PFF) compared to their CB stem counterparts. The risk of both intraoperative and postoperative PFF remains greater with uncemented stems compared to either of these cemented stem subtypes. PFF continues to be a devastating complication following primary THA and is associated with high complication and mortality rates. Recent efforts have focused on identifying implant-related risk factors for PFF in order to guide preventative strategies, and therefore the purpose of this article is to present the current evidence on the effect of cemented femoral stem design on the risk of PFF.

Return to driving post upper or lower extremity orthopaedic surgical procedures: a scoping review of current published literature.

Patients undergoing planned or unplanned orthopaedic procedures involving their upper or lower extremity can prevent them from safe and timely return to driving, where they commonly ask, 'Doctor, when can I drive?' Driving recommendations after such procedures are varied. The current evidence available is based on a heterogenous data set with varying degrees of sample size and markedly differing study designs. This instructional review article provides a scoping overview of studies looking at return to driving after upper or lower extremity surgery in both trauma and elective settings and, where possible, to provide clinical recommendations for return to driving. Medline, EMBASE, SCOPUS, and Web of Science databases were searched according to a defined search protocol to elicit eligible studies. Articles were included if they reviewed adult drivers who underwent upper or lower extremity orthopaedic procedures, were written in English, and offered recommendations about driving. A total of 68 articles were included in the analysis, with 36 assessing the lower extremity and 37 reviewing the upper extremity. The evidence available from the studies reviewed was of poor methodological quality. There was a lack of adequately powered, high quality, randomised controlled trials (RCTs) with large sample sizes to assess safe return to driving for differing subset of injuries. Many articles provide generic guidelines on return to driving when patients feel safe to perform an emergency stop procedure with adequate steering wheel control. In future, RCTs should be performed to develop definitive return to driving protocols in patients undergoing upper and lower extremity procedures.

Simultaneous Hip Implant Segmentation and Gruen Landmarks Detection.

The assessment of implant status and complications of Total Hip Replacement (THR) relies mainly on the clinical evaluation of the X-ray images to analyse the implant and the surrounding rigid structures. Current clinical practise depends on the manual identification of important landmarks to define the implant boundary and to analyse many features in arthroplasty X-ray images, which is time-consuming and could be prone to human error. Semantic segmentation based on the Convolutional Neural Network (CNN) has demonstrated successful results in many medical segmentation tasks. However, these networks cannot define explicit properties that lead to inaccurate segmentation, especially with the limited size of image datasets. Our work integrates clinical knowledge with CNN to segment the implant and detect important features simultaneously. This is instrumental in the diagnosis of complications of arthroplasty, particularly for loose implant and implant-closed bone fractures, where the location of the fracture in relation to the implant must be accurately determined. In this work, we define the points of interest using Gruen zones that represent the interface of the implant with the surrounding bone to build a Statistical Shape Model (SSM). We propose a multitask CNN that combines regression of pose and shape parameters constructed from the SSM and semantic segmentation of the implant. This integrated approach has improved the estimation of implant shape, from 74% to 80% dice score, making segmentation realistic and allowing automatic detection of Gruen zones. To train and evaluate our method, we generated a dataset of annotated hip arthroplasty X-ray images that will be made available.

The Feasibility of Hinged Knee Arthrodiastasis for Cartilage Regeneration: A Systematic Review of the Literature.

Introduction: Knee joint distraction (KJD) is a potential technique for cartilage regeneration in young patients with osteoarthritis of the knee. Static distraction has been utilised typically; however, a significant proportion of patients complain of knee stiffness post-distractor removal. The use of a hinged distractor may reduce the duration and severity of post-treatment knee stiffness by maintaining the range of motion during distraction. Furthermore, improved cartilage regeneration has been demonstrated in hinged ankle joint distraction as compared to static, and this may also be demonstrated at the knee. An evidence review was undertaken to inform further research and a potential change in practice. Aim: A systematic review of all primary research on hinged knee joint distraction for cartilage regeneration. Methods: An online systematic search of citation databases was conducted. Quality assessment and data extraction were undertaken by two separate researchers. Results: The literature search returned a small number of relevant studies, of which 7 were included. Three of these were animal studies, two cadaveric and two case series. The study quality was low or very low. There was significant methodological heterogeneity with difficulties encountered in the transfer of constructs from animal and cadaveric studies to humans. Issues faced included difficulties with hinge placement and pin site pain in motion. Conclusion: The feasibility of hinged knee joint distraction has yet to be proven. Any further research attempting to establish the benefits of hinged-over static knee distraction will have to take construct design considerations into account. How to cite this article: Lineham B, van Duren B, Harwood P, et al. The Feasibility of Hinged Knee Arthrodiastasis for Cartilage Regeneration: A Systematic Review of the Literature. Strategies Trauma Limb Reconstr 2023;18(1):37-43.

Preoperative Templating for Total Hip Arthroplasty: A Method for Calibrating Digital Radiographs Using Patient Demographics and Anthropometric Measurements.

Background Preoperative templating aids the surgeon in estimating implant size and placement. Calibration markers are used to set the correct magnification of digital images before templating. Improper marker placement or complete absence can lead to inaccuracy or an inability to calibrate images altogether. Aims This study describes a method for calibrating images using a patient's femoral head size (FHS) predicted using demographics and anthropometric data. Materials and methods A formula predicting the FHS was derived from a cohort of 507 patients who underwent hemiarthroplasty for an intracapsular fractured neck of the femur through multivariate regression analysis. A separate validation cohort (n=50) who had undergone total hip arthroplasty (THA) had postoperative radiographs calibrated using the predicted FHS and the native contralateral hip as a surrogate calibration marker. The THA femoral head implant size was subsequently measured and compared with the actual implant size selected intraoperatively. Measurements were performed by two independent assessors to determine intra- and interobserver reliability. Results Multivariate regression analyses showed four variables significantly correlated with the size of the femoral head: gender (p < 0.001), height (p < 0.001), weight (p < 0.001), and race (Asian) (p = 0.01). Using these, a regression model to predict the FHS was obtained with an R2 value of 0.65 and a standard error of 2.18 mm. The validation cohort showed that THA head implant size could be accurately measured with an average root-mean-squared error (RMSE) of 1.41 mm (SD = 0.97 mm; %RMSE = 4.7%). The implant head size was measured to be within 5%, 10%, and 15% RMSE in 57.5%, 93.0%, and 100.0% of cases, respectively. There was excellent intraobserver (R2 = 0.94 and 0.95) and interobserver (R2 = 0.94) reliability. Conclusions The novel method proposed and validated in this study, using a predicted FHS to calibrate digital images, provides an alternative means of templating THA for fractured neck of the femur patients, in whom external calibration markers are often absent.

National Registry Data Analysis on a Unique Highly-Crosslinked Polyethylene for Total Hip Arthroplasty.

Background: Several types of highly-crosslinked polyethylene with different manufacturing processes and mechanical properties are commercially available, including HIGHCROSS (Medacta). The aim of this registry study is to ascertain the long-term safety of the HIGHCROSS liners in total hip arthroplasty and compare the revision rates with its contemporaries using real-world data to establish their safety and generalizability when used by multiple surgeons. Methods: The Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) and the Swiss National Joint Registry (SIRIS) were selected for the large number of users of Medacta implants and the availability of long-term results. Three reports from SIRIS and 4 reports from AOANJRR were examined to establish the overall and Kaplan-Meier (KM) cumulative revision rate. Results: According to SIRIS, the HIGHCROSS liner was the most commonly used bearing surface with Medacta stems with overall revision rates for wear/osteolysis at 9.7 years of 0.04% and 0.03%, respectively, for AMIStem and Quadra. Based on AOANJRR, the KM cumulative revision rate for any reason of Medacta stems with HIGHCROSS liners was lower than that with ceramic liners at 3 years for MasterLoc and at 10 years for Quadra. The KM cumulative revision rate for any reasons of Medacta cementless cups with HIGHCROSS liners at 12 years was lower than the comparator made of all other implants and tribological couplings (1.6% vs 2.1%). Conclusions: This real-world data proves that long-term HIGHCROSS survival rates are comparable to other modern bearing surfaces.

National variation in prophylactic antibiotic use for elective primary total joint replacement.

Aims: Prophylactic antibiotic regimens for elective primary total hip and knee arthroplasty vary widely across hospitals and trusts in the UK. This study aimed to identify antibiotic prophylaxis regimens currently in use for elective primary arthroplasty across the UK, establish variations in antibiotic prophylaxis regimens and their impact on the risk of periprosthetic joint infection (PJI) in the first-year post-index procedure, and evaluate adherence to current international consensus guidance. Methods: The guidelines for the primary and alternative recommended prophylactic antibiotic regimens in clean orthopaedic surgery (primary arthroplasty) for 109 hospitals and trusts across the UK were sought by searching each trust and hospital's website (intranet webpages), and by using the MicroGuide app. The mean cost of each antibiotic regimen was calculated using price data from the British National Formulary (BNF). Regimens were then compared to the 2018 Philadelphia Consensus Guidance, to evaluate adherence to international guidance. Results: The primary choice and dosing of the prophylactic antimicrobial regimens varied widely. The two most used regimens were combined teicoplanin and gentamicin, and cefuroxime followed by two or three doses of cefuroxime eight-hourly, recommended by 24 centres (22.02%) each. The alternative choice and dosing of the prophylactic antimicrobial regimen also varied widely across the 83 centres with data available. Prophylaxis regimens across some centres fail to cover the likeliest causes of surgical site infection (SSI). Five centres (4.59%) recommend co-amoxiclav, which confers no Staphylococcus coverage, while 33 centres (30.28%) recommend cefuroxime, which confers no Enterococcus coverage. Limited adherence to 2018 Philadelphia Consensus Guidance was observed, with 67 centres (61.50%) not including a cephalosporin in their guidance. Conclusion: This analysis of guidance on antimicrobial prophylaxis in primary arthroplasty across 109 hospitals and trusts in the UK has identified widespread variation in primary and alternative antimicrobial regimens currently recommended.