[Improving the Accuracy of Patient Self-Care After Joint Replacement Surgery].

BACKGROUND & PROBLEMS: Joint replacement wound stitches are typically not removed until two weeks after the operation. Therefore, patients with joint replacement must be able to execute proper wound care after discharge from the hospital to reduce the risk of wound infection. Prior data from Chang Gung Memorial Hospital's orthopedics ward indicate only 69% of joint-replacement patients are able to perform wound care properly at home. Potential causes for this noted by patients include age-related forgetfulness, being unable to discern redness or swelling in the wound, and language comprehension difficulties (i.e., Taiwanese vs. Mandarin). Poor rates of wound care may also be attributable to incomplete wound care education by nursing staff and wound care education being provided without adequate practice on the day of patient discharge. PURPOSE: This project was implemented to improve the accuracy of wound self-care performed by patients after joint replacement surgery and to enhance their related knowledge and wound-care technical correctness. RESOLUTION: A wound care education checklist, wound care cue cards, wound care video clips, wound condition red flag cue cards, and customized wound care pack were proposed and implemented. RESULTS: The rate of accuracy of wound self-care performance increased from 69% pretest to 98% posttest, showing the intervention to have effectively improved post-discharge wound care quality. CONCLUSIONS: To effectively improve the post-discharge accuracy of wound self-care in patients with joint replacement, the consistency of post-surgery wound care education given by nursing staff to patients should be improved, patients should be reminded of wound assessment and care steps, and patients should be aware that wound abnormalities require an immediate return to the hospital for follow-up treatment.

A Rare Case of Posterior Dislocation of Hinge Knee Prosthesis due to Wear of Anti-Luxation Device: A Case Report.

Introduction: Hinge knee joint prosthesis are utilized in a variety of surgical scenarios, including complex primary, revision, salvage surgeries, and radical resection of tumor's. Link's Endo-model Hinged Knee Prosthesis is a newer design that includes ramped tibial components for controlled pivot point motion during flexion and an anti-dislocation feature to prevent prosthesis dislocation.. The re-design of the hinge prosthesis has resulted in less force transfer along the implant bone junction. However, despite the improved design, complications can still arise. This report presents a rare complication of posterior dislocation due to polythene wear of the anti-dislocation device in a patient with a rotating hinge knee prosthesis. Case Report: After 4 years, a 42-year-old patient who had undergone multiple total knee replacements (TKRs) with a history of pain, swelling, and difficulty walking for the previous 2 months presented to us. Radiographs from the initial presentation revealed aseptic loosening, for which a revision TKR using a Link-Waldemier non-modular (rotational) joint endo-model with an anti-dislocation mechanism was performed. Three years later, the patient began experiencing episodes of instability, and a radiograph revealed posterior dislocation of the hinge knee prosthesis. As a result, a decision was made to perform revision surgery, during which the worn-out polyethylene was replaced with a new polyethylene insert, and stability was confirmed intraoperatively. Four weeks after surgery, the patient's knee range of motion was 0-120°, and all discomfort had completely subsided. At a year's follow-up, the patient's Knee Society score had improved from 40 before surgery to 90 after surgery. Conclusion: Interference in the normal framework of knee anatomy distorts its intrinsic stability. This interference can be in variable form such as bone deficiency, infection, multiple revision surgeries, and ligamentous laxity. Restoration of intrinsic stability in today's world has been made possible by a highly constraint, hinged knee prosthesis. An anti-dislocation mechanism on the rotating hinge prosthesis guards against dislocation brought on by distracted engagement. In our instance, the anti-dislocation mechanism had aseptically loosened, increasing flexion laxity and permitting severe distraction. The anti-dislocation mechanism will eventually relax, but its lifespan can be increased by proper gap balancing, which offers inherent stability and increases the anti-dislocation mechanism's stability.

Vascular Injury during Total Knee Replacement and Check List to Follow in its Management: Case Report.

Introduction: Vascular injury during total knee replacement (TKR) is a rare but potentially serious complication. Early recognition and prompt intervention are crucial for managing these injuries effectively. Interdisciplinary collaboration with a vascular surgeon is essential to optimize patient outcomes, minimizing the risk of limb loss and other long-term complications. Case Report: We present a case of a 68-year-old woman with bilateral knee osteoarthritis who underwent bilateral TKR in a single surgical session with the right knee being the first knee. During left knee replacement, pulsatile bleeding was observed behind the femoral notch, following tourniquet deflation. Hemostasis was achieved and the procedure was completed. The patient's oxygen saturation in the left lower limb decreased postoperatively. Computed tomography angiography revealed a 4.5 cm long thrombus in the popliteal artery at the knee joint level with adequate distal runoff. Digital subtraction angiography confirmed the blockage again with collateral vessel refilling. A decision was made to undertake an exploration to address the blockage, aiming to prevent further extension of the thrombus to the bifurcation of the popliteal artery. Surgical exploration revealed a laceration and thrombus in the popliteal artery, thrombectomy was done with Fogarty which was followed by end-to-end repair. The patient's post-operative course was closely monitored. The patient went on to have a successful outcome and recovered well. Conclusion: This case highlights the importance of early recognition, careful patient assessment, and immediate communication with an interventional radiologist and vascular surgeon in patients with suspected vascular injury during TKR. Interdisciplinary collaboration among orthopedic surgeons, interventional radiologists, and vascular surgeons is essential for optimizing patient outcomes in such cases.

A radiographic artificial intelligence tool to identify candidates suitable for partial knee arthroplasty.

INTRODUCTION: Knee osteoarthritis is a prevalent condition frequently necessitating knee replacement surgery, with demand projected to rise substantially. Partial knee arthroplasty (PKA) offers advantages over total knee arthroplasty (TKA), yet its utilisation remains low despite guidance recommending consideration alongside TKA in shared decision making. Radiographic decision aids exist but are underutilised due to clinician time constraints. MATERIALS AND METHODS: This research develops a novel radiographic artificial intelligence (AI) tool using a dataset of knee radiographs and a panel of expert orthopaedic surgeons' assessments. Six AI models were trained to identify PKA candidacy. RESULTS: 1241 labelled four-view radiograph series were included. Models achieved statistically significant accuracies above random assignment, with EfficientNet-ES demonstrating the highest performance (AUC 95%, F1 score 83% and accuracy 80%). CONCLUSIONS: The AI decision tool shows promise in identifying PKA candidates, potentially addressing underutilisation of this procedure. Its integration into clinical practice could enhance shared decision making and improve patient outcomes. Further validation and implementation studies are warranted to assess real-world utility and impact.

Osteoporosis in the setting of knee arthroplasty: a narrative review.

Patients undergoing knee replacement, which is mainly indicated in severe osteoarthritis, are frequently co-affected by osteoporosis and osteopenia. With a prevalence standing at around 20% in patients receiving knee arthroplasty, osteoporosis could lead to poor outcomes postoperatively. Some of these complications include periprosthetic fractures and an increased revision rate. Antiresorptive medications have been shown to be beneficial postoperatively. However, no studies have been conducted on whether they had any benefits if given preoperatively. Surgical management may also be beneficial, but this area remains full of controversy.

An Intraoperative Technique to Assess Tissue Tension and Leg Length When Aligning the Hip Centre of Rotation With the Acetabulum in Hip Arthroplasties.

Hip arthroplasties are cost-effective procedures; however, instability and leg length discrepancy are common complications that can lead to higher revision rates and patient dissatisfaction. Preoperative planning aids surgeons in choosing the right offset and neck length before surgery. Nonetheless, intraoperative measures are still necessary due to the differences dictated by the surgical procedure. Several hip trials might be needed to reach the optimum choice of implants. We have introduced a technique that utilizes the trunnion as a reference point to the hip centre of rotation, matching it with the acetabulum centre of rotation after applying the necessary soft tissue tension. This serves as a proximal reference point. Using the trunnion, as opposed to the trial head, allows for a better assessment of tissue tension within the acetabular void, avoiding constraints imposed by the applied trial head. Additionally, determining the acetabulum's centre of rotation is challenging if obscured by the trial head. Matching the two tibial tuberosities indicates the correct leg length, serving as the distal reference point. Both reference points should be considered together to select the right neck length and offset for optimal tissue tension. This technique has been tested on hip arthroplasty patients over five years. All hip surgeons who used this technique agree that it gives a better representation of the tissue tension, easing the challenges when preparing the acetabulum as well as reducing the need for multiple trials.

[Total knee replacement in patients under 60 years with high functional demand: functional outcomes and return to sports after an average 2-year follow-up]. / Reemplazo total de rodilla en pacientes menores de 60 años con demanda funcional elevada: resultados funcionales y retorno al deporte después de un promedio de dos años de seguimiento.

INTRODUCTION: a common concern in presurgical medical appointment of total knee replacement medical appointment is return to exercise. The purpose of this study was to analyze functional results and return to sport in patients under 60 years of age after this surgery. MATERIAL AND METHODS: we retrospectively analyzed 41 total knee replacements in 36 athletic patients (average age: 53 years [46-60]). Average follow-up of two years (6 months-5 years). Diagnoses: 37 osteoarthritis, three sequelae of Rheumatoid Arthritis, 1 extra-articular deformity. Functional and radiographic outcomes assessed using modified Knee Society and High Activity Arthroplasty Scores. RESULTS: average improvement from 31.95 to 91.61 in KSS and average from 7.95 to 13.73 in HAAS. Return to sport in 3.5 months average (range 2-6 months). Three patients did not return to sport. CONCLUSIONS: we consider that delaying surgery in these patients will cause progression in their osteoarthritis pathology and cessation of their sports activities. This makes the surgical technique difficult in addition to reducing the patient's physical performance. Analyzing the survival rate of implants in young patients, more than 80% is reported in a 25-year follow-up.

INTRODUCCIÓN: una inquietud frecuente en consultas prequirúrgicas de reemplazo total de rodilla es el regreso al ejercicio. El propósito de este estudio fue analizar resultados funcionales y retorno al deporte en pacientes menores de 60 años posterior a esta cirugía. MATERIAL Y MÉTODOS: analizamos retrospectivamente 41 reemplazos totales de rodilla en 36 pacientes deportistas (edad promedio: 53 años [46-60]). Seguimiento promedio de dos años (6 meses-5 años). Diagnósticos: 37 gonartrosis, tres secuelas de artritis reumatoidea, una deformidad extraarticular. Resultados funcionales y radiográficos evaluados mediante Knee Society modificado y High Activity Arthroplasty Score. RESULTADOS: mejoría promedio de 31.95 a 91.61 en KSS y promedio de 7.95 a 13.73 en HAAS. Retorno al deporte en 3.5 meses promedio (rango: 2-6 meses). Tres pacientes no retornaron al deporte. CONCLUSIONES: consideramos que el retraso de la cirugía en estos pacientes producirá progresión en su patología artrósica y cese de sus actividades deportivas. Esto dificulta la técnica quirúrgica además de disminuir el rendimiento físico del paciente. Analizando la tasa de supervivencia de implantes en pacientes jóvenes, se reporta más de 80% en seguimientos de 25 años.

Carbon savings associated with changing surgical trends in total knee arthroplasty in England: a retrospective observational study using administrative data.

BACKGROUND: Best practice pathways for common surgical procedures, including total knee arthroplasty (TKA), have the potential to improve patient outcomes and reduce carbon emissions. We aimed to estimate the reduction in carbon emissions due to changing trends in the care of patients undergoing TKA in England. METHODS: This was a retrospective analysis of Hospital Episode Statistics data from 1 April 2013 to 31 March 2022 on adults undergoing elective primary TKA in England. The carbon footprint for each patient was calculated using carbon factors for multiple steps in the pathway, including ipsilateral knee arthroscopies in the year preceding the TKA, outpatient attendances, the index TKA, revisions of the TKA performed within 180 days of the index procedure, length of hospital stay and emergency readmissions. RESULTS: A total of 648,861 TKA operations were identified. Over the study period, the median length of stay reduced from four to three days, the proportion of patients undergoing ipsilateral knee arthroscopies performed within a year before TKA surgery fell from 5.9% to 0.5% and the number of early revisions and emergency readmissions also fell. The per-patient carbon footprint reduced from 378.8kgCO2e to 295.2kgCO2e over this time. If all the study patients had the same carbon footprint as the average patient in 2021/2022, 32.4kilotons CO2e would have been saved, enough to power 29,509 UK homes for one year. CONCLUSIONS: Practices that were introduced primarily to improve patient outcomes can contribute to a reduction in the carbon footprint.

A 10-point preoperative checklist: selecting patients for outpatient joint replacement surgery.

BACKGROUND: With advancements in perioperative care, joint replacement (JR) surgery is undergoing a transition from opacified in-patient institutions to nimble out-patient Ambulatory Surgical Centers (ASC). The goal of JR in ASC setting is safe patient discharge with subsequent rehabilitation without readmission. Multi-modal preoperative rehabilitation (MMPR) is a novel field of perioperative care, encompassing comprehensive parameters to ensure smooth transition from fitness for surgery to JR in outpatient setting. At present, there are no open-access schemes for selecting patients qualified for JR in the ASC setting. In this article, we propose an evidence-based, 10-point systematic evaluation of patients with target endpoints for MMPR to qualify patients for JR as an outpatient procedure. This checklist is a non-proprietary scheme serving as an initial framework for surgeons exploring surgery in the ASC setting. BODY: We introduce factors for a prehabilitation scheme, called Checklist Outpatient-Joint Replacement (CO-JR) to qualify patients for outpatient JR surgery. These factors have been developed based on an extensive literature review and the significant experience of authors to incorporate variables that drive a successful outpatient JR procedure. The factors include patient education, psychiatric & cognitive ability, medical fitness, musculoskeletal capability, financial ability, transportation access, patient motivation, information technology (IT) capabilities, along with ability to recover independently at home postoperatively. The CO-JR scheme is under the process of validation at multiple institutions. We introduce this as a starting point for collaborative development of an open-access scheme for all surgeons to learn and adapt as needed for their respective global region. CONCLUSION: We established a non-proprietary 10-point CO-JR scheme, serving as a framework for surgeons to successfully select patients for JR surgery in the ASC setting. We encourage concomitant validation of this scheme globally. Our goal is to reach an international consensus on an open-access scheme, available for all surgeons to enrol patients for JR in the ASC setting, but modifiable to accommodate regional needs.

Equal waiting times for all? Empirical evidence for elective surgeries in the Austrian public healthcare system.

OBJECTIVES: This study analyses waiting times for elective surgeries and potential determinants, including supplementary private health insurance, visits in the operating physician's private practice and informal payments for faster treatment. STUDY DESIGN: Retrospective patient questionnaire survey. METHODS: The survey was conducted in eleven Austrian rehabilitation centres in 2019. Data was analysed based on bivariate tests (n = 400) and a multivariate negative-binomial regression model (n = 310) with institution- and patient-related characteristics as independent variables. RESULTS: Median waiting times were 8.9 weeks (IQR: 4.5-18.0) for hip replacement and 8.4 weeks (IQR: 5.0-20.0) for knee replacement surgery. 10.9% of the patients reported having received an offer to shorten their waiting time through a visit in the operating physician's private practice before the surgery or through an informal payment directly to the operating physician. Surgery in private for-profit hospitals, supplementary private health insurance and severe pain were associated with shorter waiting times. CONCLUSIONS: While waiting times for elective surgeries in Austria are below international levels, shorter waits for patients with private health insurance and offers to reduce waiting times through informal payments point to equitable access concerns in a public healthcare system.

Magnetic resonance imaging-based biomarkers for knee osteoarthritis outcomes: A narrative review of prediction but not association studies.

BACKGROUND: Magnetic Resonance Imaging (MRI) is frequently used in recent studies on knee osteoarthritis (KOA), focusing on developing innovative MRI-based biomarkers to predict KOA outcomes. The growing volume of publications devoted to this subject highlights the need for an up-to-date review. METHODS: In this narrative review, we utilized the PubMed database to identify studies examining MRI-based biomarkers for the prediction of knee osteoarthritis (KOA), focusing on those reporting relevant prediction, not association, metrics. The identified articles were subsequently categorized into three distinct outcomes: Prediction of KOA incidence (KOAi), KOA progression (KOAp) and total knee arthroplasty risk (TKAr). Within each category, results were organized by the nature of biomarker(s) used, as either quantitative, semi-quantitative or compound. RESULTS: Due to the lack of predictive metrics such as the area under the ROC curve (AUC) scores, sensitivity or specificity, 27 studies were excluded. A final set of 23 studies were deemed eligible for our analysis. The mean AUC scores reported ranged from 0.67 to 0.83 for predicting KOAi, 0.54 to 0.84 for KOAp and 0.55 to 0.94 for TKAr. Excellent predictive performance (AUC>0.8) was observed for the prediction of radiographic KOAi, KOAp and TKAr when using cartilage and meniscal-based measures, osteophyte scores and infrapatellar fat pad texture, and bone marrow lesions, respectively. CONCLUSION: The results showed that numerous studies highlighted the importance of MRI-based biomarkers as promising predictors of the three key outcomes. In addition, this narrative review also emphasized the necessity for KOA prediction studies to include adequate reporting of predictive metrics.

Herpes Zoster Risk After Total Knee Replacement: a multicenter, propensity-score-matched cohort study in the United States.

Background: Total knee replacement (TKR) is a common surgical procedure for osteoarthritis (OA) patients. TKR may increase susceptibility to herpes zoster (HZ) by inducing immunosuppression, surgical stress, and nerve injury. However, limited data exist on the relationship between TKR and HZ. This study examined the risk of HZ over time among OA patients who underwent TKR and those who did not, using a large population-based cohort. Method: Utilizing the TriNetX research network, people with OA and underwent TKR were recruited as case group. After 1:1 propensity score matching, OA patients who never experienced TKR were included as control group. Covariates, including demographics, comorbidities, and laboratory data, were balanced using propensity score matching. A 5-year follow-up assessed the hazard ratio of incident HZ and related complications. Results: Compared to the control group, a significantly elevated risk of HZ was observed in the TKR cohort across 5-year follow-up period, with the hazard ratio of 1.223 (95% CI: 1.089-1.373). Zoster without complications presented 1.173-fold risk in TKR patients while comparing with non-TKR controls. However, most other secondary outcomes related to HZ complications-such as encephalitis, neurological involvement, ocular disease, and disseminated zoster-did not show a significant increase in risk. The risk of HZ was statistically significant for females and older adults in the TKR cohort than in the control cohort. Conclusions: OA patients who underwent TKR had an increased risk of HZ compared to those who did not receive the procedure, especially females and older adults. These findings highlight the need for HZ monitoring/prevention protocols and further research on mitigating viral reactivation after major joint surgery.

Prospective Assessment of Outcomes After Femoral Condyle Osteochondral Allograft Transplantation With Concurrent Meniscus Allograft Transplantation.

Background: Osteochondral allograft transplantation (OCAT) and meniscus allograft transplantation (MAT) have each become more commonly implemented for the treatment of young to middle-aged patients with complex knee pathology. Evidence regarding tibiofemoral OCAT in the setting of concurrent MAT is limited. Purpose/Hypothesis: The purpose of this study was to characterize outcomes for femoral condyle OCAT with concurrent MAT (OCAT+MAT) in the ipsilateral compartment of patients after evidence-based shifts in practice. It was hypothesized that OCAT+MAT would be associated with successful outcomes characterized by statistically significant and clinically meaningful improvements in patient-reported outcome measures (PROMs) of knee pain and function in >80% of patients for at least 2 years after transplantation. Study Design: Case series; Level of evidence, 4. Methods: With institutional review board approval and documented informed consent, patients who underwent primary OCAT+MAT between 2016 and 2020 and enrolled in a lifelong registry for prospective collection of outcomes after OCAT were included. Patients with minimum 2-year follow-up data regarding complications, failures, adherence, and PROMs were analyzed. Patients who required OCAT and/or MAT revision or conversion to arthroplasty were defined as experiencing treatment failures. Results: A total of 23 consecutive patients (mean age, 37.1 years; mean body mass index, 28 kg/m2; 14 men) met the inclusion criteria, with a mean follow-up of 51 months (range, 24-86 months). The initial treatment success rate was 78% based on 5 initial treatment failures, and the overall success rate was 83% based on a successful revision OCAT. All failures occurred in the medial compartment. Older patient age (42.2 vs 32.1 years; P = .046) and nonadherence to postoperative restriction and rehabilitation protocols (P = .033; odds ratio, 14) were significant risk factors for treatment failure. All measured PROMs achieved significant improvements (P < .001) and minimum clinically important differences at a minimum of 2 years postoperatively. Conclusion: OCAT+MAT was associated with successful short- to mid-term outcomes in 83% of cases. Evidence-based shifts in practice were implemented before the enrollment of this patient cohort. Older patients and those who were not adherent to postoperative restriction and rehabilitation protocols had a significantly higher risk for treatment failure and subsequent conversion to arthroplasty.

A Systematic Review of the Effectiveness of Rehabilitation Programmes or Strategies to Treat People With Persistent Knee Pain Following a Total Knee Replacement.

BACKGROUND: Persistent high levels of knee pain after a total knee replacement have been estimated to affect 5%-10% of people and this is related to dissatisfaction with surgery, reduced function and reduced quality of life. This systematic review aims to evaluate the effectiveness of rehabilitation programs or strategies to reduce persistent pain and improve function and quality of life in people following a total knee replacement. METHODS: The systematic review was conducted following PRISMA guidelines with a search of relevant online databases up to 17 July 2024. The search criteria included English language randomised controlled trials of rehabilitation programs or strategies in any setting to treat people with persistent knee pain more than 3 months after a total knee replacement. Rehabilitation could include exercise, education, cognitive strategies and self-management programs and excluded medication trials, procedural techniques and complementary therapies. RESULTS: After removal of duplicates, there were 468 abstracts screened for eligibility with 23 remaining for full-text screening and finally, one study meeting the eligibility criteria. This study's interventions were pain neuroscience education alone and pain neuroscience education plus neuromuscular exercise. There were no statistically significant between-group differences for pain reduction or functional improvement. CONCLUSION: The evidence examining the value of rehabilitation programs or strategies for pain reduction and functional improvement in people with persistent pain following total knee replacement is deficient. Given the high number of people affected annually, further research concerning both prevention and management of persistent pain after knee replacement is warranted.

[Postoperative rehabilitation after knee arthroplasty]. / Postoperative Rehabilitation nach Knieendoprothetik.

BACKGROUND: Postoperative rehabilitation after knee arthroplasty plays a decisive role in restoring the function and mobility of the affected joint. However, there is still disagreement regarding the setting, structure and content of rehabilitation after knee arthroplasty, and the evidence on the individual measures is largely unclear. The aim of this article is to provide an evidence-based overview of the current status of rehabilitation after knee arthroplasty and to critically discuss the points that are still unclear. In view of the increasing prevalence of knee osteoarthritis and the rising number of knee endoprosthesis implantations, the optimization and scientific processing of postoperative rehabilitation is more important than ever in order to be able to offer scientifically sound, practice-oriented and cost-effective rehabilitation measures in the future. MATERIAL AND METHODS: This review is based on a systematic literature search in Medline, Cochrane Library and Web of Science databases on the topic of postoperative rehabilitation after knee arthroplasty. RESULTS: Regarding specific treatment components, duration and frequency after knee arthroplasty, the evidence is unclear. Passive therapies should only be used supportive to active interventions. Educational programmes before and after knee arthroplasty can play a crucial role in outcome and patient satisfaction. Regular strength training should always be combined with centrally oriented components, such as motor imagery, to achieve better movement visualization and central anchoring. There is still a frequent lack of scientific evidence regarding individual therapeutic measures, their intensity, frequency, duration, exercise selection and their specific implementation in rehabilitation after knee arthroplasty. In the future, digital diagnostic and training tools will become established in both inpatient and outpatient therapy, supporting the urgently needed data collection for the scientific analysis of individual therapeutic measures.

Number of conditioning trials, but not stimulus intensity, influences operant conditioning of brain responses after total knee arthroplasty.

PURPOSE: The primary purpose of this randomized, cross-sectional study was to determine whether operant conditioning of motor evoked torque (MEPTORQUE) in individuals with total knee arthroplasty (TKA) increases quadriceps MEPTORQUE responses within a single session and induces acute corticospinal adaptations by producing sustained increases in MEPTORQUE after training. A secondary purpose was to determine if these changes were affected by the stimulus intensity and number of training trials. METHODS: Thirty participants were block-randomized into one of three groups based on the participant's active motor threshold (100%, 120%, and 140%) to evaluate the effect of stimulus intensity. Participants received three blocks of conditioning trials (COND), where they trained to increase their MEPTORQUE. Control (CTRL) transcranial magnetic stimulation pulses were provided before and after each COND block to establish baseline corticospinal excitability and to evaluate the effect of the number of training trials. Two MEPTORQUE recruitment curves were collected to evaluate the effect of up-conditioning on acute corticospinal adaptations. RESULTS: TKA participants were able to successfully increase their MEPTORQUE in a single session (F3,81 = 10.719, p < 0.001) and induce acute corticospinal adaptations (F1,27 = 20.029, p < 0.001), indicating sustained increases in quadriceps corticospinal excitability due to operant conditioning. While the stimulus intensity used during training did not affect the ability to increase MEPTORQUE (F2,26 = 0.021, n.s.) or its associated acute adaptations (F2,27 = 0.935, n.s.), the number of training trials significantly influenced these outcomes (F3,81 = 10.719, p < 0.001; F3,81 = 4.379, p = 0.007, respectively). CONCLUSION: Operant conditioning is a feasible approach for improving quadriceps corticospinal excitability following TKA. While any of the three stimulus intensities evaluated in this study may be used in future operant conditioning interventions, using a low or moderate stimulus intensity and 150 training trials are recommended to improve treatment efficiency and patient adherence. LEVEL OF EVIDENCE: Level II.

Predictors of outcome following two-stage revision total knee arthroplasty.

PURPOSE: Two stage revision arthroplasty remains the gold standard for peri-prosthetic joint infections of the knee. However, the functional outcomes of revision surgeries and the factors governing them require further investigation. The purpose of this study was to (a) evaluate impact of early and late stage I surgery and interval between stage I and stage II; (b) understand the impact of infecting organism and resistance; (c) to estimate long term survivorship and causes of failure. METHODS: A retrospective review of 86 patients, who underwent two stage revision for prosthetic joint infections of the knee, was performed. Time between onset of symptoms to stage I (T1), and T1 to re-implantation (T2), along with microbiological studies, were analysed for their impact on functional outcomes, failure modalities and survivorship. RESULTS: In this study, the mean KSS-Knee improved from 64.0 ± 10.0 pre-operatively to 76.9 ± 10.4, and 77.2 ± 10.1 at the 5 and 10 year follow up respectively. The KSS-Function improved from 44.4 ± 8.8 pre-operatively to 72.2 ± 9.5 and 79.8 ± 8.1 at 5 and 10 year follow-up respectively. This study also found that T1 and T2 remained critical factors in determining functional outcome and longevity of the implant and a delay in these intervals was a significant predictor of failure. Gram negative, poly-microbial infections and organisms with methicillin and vancomycin resistance demonstrated lower survivorship (p-value, 0.001 at 5, 10 and 12 years). Re-infections occurred in 4 cases while 9 cases failed due to aseptic causes. CONCLUSION: Two-stage revision arthroplasty produced good functional outcomes when the infection was caused by single sensitive organism that did not exhibit high resistance to antibiotics. Stage I performed within 4 weeks and the subsequent re-implantation procedure undertaken within 6 weeks demonstrated better outcomes.

Functional outcome after bicompartmental knee replacement for medial and patellofemoral osteoarthritis.

INTRODUCTION: Total knee arthroplasty (TKA) is used for tricompartmental knee osteoarthritis, while unicompartmental knee arthroplasty (UKA) is preferred for unicompartmental knee osteoarthritis. Bicompartmental knee arthroplasty (BKA) aims to address 2 knee compartments by combining 2 UKA's or 1 UKA with a patellofemoral replacement. This study examines the clinical outcomes of BKA, focusing on pain alleviation and knee function. The aim of this study is to report the functional outcome of BKA and see if this aligns with BKA outcomes from literature in terms of patient reported outcome measurements (PROMs) and range of motion (ROM) after a 2-year follow-up. Additionally, radiographic alignment, implant survivorship, adverse events and length of stay are secondary outcomes. METHODS: This is a cohort study of 21 patients who underwent BKA for medial and patellofemoral osteoarthritis. The patients had follow-up for at least 2 years postoperatively. PROMs were assessed using the Knee injury and Osteoarthritis Outcome Score (KOOS), Knee Society Score (KSS), Oxford Knee Score, Western Ontario and McMaster University Osteoarthritis index (WOMAC) and the Visual Analogue Scale (VAS). ROM was measured using a goniometer. Pre- and postoperative radiographic coronal alignment was measured using standard full leg radiographs. Patient demographics, implant survivorship, length of stay and adverse events were recorded. RESULT: Twenty-one patients (23 knees) were included, with a mean follow-up of 41 months (standard deviation [SD] 12 months; range 24-59 months). Patient-reported outcome measures (PROMs) demonstrated significant improvements, with 80% achieving good to excellent OKS and KSS scores. KOOS scores were similar to scores found in literature. The WOMAC score was higher in our results compared to other authors. Which indicates worse outcome. The mean preoperative hip-knee-ankle angle (HKAA) was 2.4 degrees varus (SD 1.9 degrees; range 1.2 degrees valgus - 6.1 degrees varus), while the mean postoperative HKAA was 0.3 degrees valgus (SD 2.8 degrees; range 4.6 degrees valgus - 5.6 degrees varus) (p < 0.001). Postoperative range of motion averaged 117 degrees (SD 10 degrees; range 98-132). CONCLUSIONS: BKA shows promise in alleviating pain and improving knee function in patients with medial and patellofemoral osteoarthritis. Challenges include the risk of revision and technical difficulties during surgery. Comparative studies suggest similar outcomes between BKA and TKA, with potential advantages for younger, more active patients. Further research, particularly randomized trials with larger cohorts, is necessary to elucidate the long-term benefits and drawbacks of BKA compared to other knee arthroplasty options.

Reliability of pre-resection ligament tension assessment in imageless robotic assisted total knee replacement.

BACKGROUND: Ligament tension balance is a major determinant for the success of total knee replacement (TKR). The present study aimed at determining the inter-rater and intra-rater reliability in performing ligament tension assessment using an imageless robotic-assisted TKR. METHODS: Twenty-four knees in 21 patients who received robotic-assisted TKR for end-stage varus osteoarthritis were examined. Three orthopedic specialists and six orthopedic trainees participated in the operations. Data from the ligament tension assessment were collected during the operations. RESULTS: For the inter-rater reliability, "extension medial" and "flexion medial" had excellent reliability whilst "extension lateral" and "flexion lateral" had good-to-excellent reliability. For the intra-rater reliability, "extension medial" showed excellent reliability, "extension lateral" and "flexion medial" showed good-to-excellent reliability, and "flexion lateral" showed moderate-to-excellent reliability. CONCLUSIONS: Robotic-assisted technology provides a reliable solution to improve ligament tension assessment. All ligament tension assessments with the use of the technology could demonstrate at least good-to-excellent reliability except for the intra-rater reliability of "flexion lateral".

No difference in clinical outcomes when retaining or sacrificing the posterior cruciate ligament in medial congruent total knee replacement. A retrospective study.

PURPOSE: The aim of this study is to evaluate the effect of retaining or sacrificing the posterior cruciate ligament (PCL) in patients who undergo primary total knee replacement (TKR) with the medial congruent (MC) implant. METHODS: This retrospective study looks at patients who underwent TKR with the MC implant. Comparison was made between the group with the PCL sacrificed (MC-PCLS) and the group with the PCL retained (MC-PCLR). Range of motion (ROM), Oxford knee score (OKS), Knee society knee score (KS-KS) and Knee society function score (KS-FS) were recorded. RESULTS: The study identified 76 patients. 50 in the MC-PCLS group and 26 in the MC-PCLR group. Both groups had similar patient demographics. Three months postoperatively, OKS and KS-KS had significant improvement. However, there was significant improvement in KS-FS score in the MC-PCLS group but not the MC-PCLR group (MC-PCLR: 33 ± 17, p = 0.07; MC-PCLS: 19 ± 24, p = 0.01). Twelve months postoperatively, the OKS continued to improve significantly for both groups, while the KS-FS and KS-KS scores appeared to stagnate. The ROM continued to improve significantly for the MC-PCLR group but not the MC-PCLS group (MC-PCLR: 7 ± 9, p = 0.03; MC-PCLS: 4 ± 9, p = 0.30). Both groups were similar in ROM, OKS and KSS scores at both the 3 and 12 month post-operative period. CONCLUSION: There is no difference in post-operative outcomes with the PCL retained or sacrificed. As such, surgeons can consider routinely sacrificing the PCL for easier balancing of the knee and shorter surgical time.