Primary Total Knee Replacement Research Articles

The clinical and cost-effectiveness of elective primary total knee replacement with PAtellar Resurfacing compared to selective patellar resurfacing: a pragmatic multicentre randomized controlled Trial (PART).

During total knee replacement (TKR), surgeons can choose whether or not to resurface the patella, with advantages and disadvantages of each approach. Recently, the National Institute for Health and Care Excellence (NICE) recommended always resurfacing the patella, rather than never doing so. NICE found insufficient evidence on selective resurfacing (surgeon's decision based on intraoperative findings and symptoms) to make recommendations. If effective, selective resurfacing could result in optimal individualized patient care. This protocol describes a randomized controlled trial to evaluate the clinical and cost-effectiveness of primary TKR with always patellar resurfacing compared to selective patellar resurfacing. The PAtellar Resurfacing Trial (PART) is a patient- and assessor-blinded multicentre, pragmatic parallel two-arm randomized superiority trial of adults undergoing elective primary TKR for primary osteoarthritis at NHS hospitals in England, with an embedded internal pilot phase (ISRCTN 33276681). Participants will be randomly allocated intraoperatively on a 1:1 basis (stratified by centre and implant type (cruciate-retaining vs cruciate-sacrificing)) to always resurface or selectively resurface the patella, once the surgeon has confirmed sufficient patellar thickness for resurfacing and that constrained implants are not required. The primary analysis will compare the Oxford Knee Score (OKS) one year after surgery. Secondary outcomes include patient-reported outcome measures at three months, six months, and one year (Knee injury and Osteoarthritis Outcome Score, OKS, EuroQol five-dimension five-level questionnaire, patient satisfaction, postoperative complications, need for further surgery, resource use, and costs). Cost-effectiveness will be measured for the lifetime of the patient. Overall, 530 patients will be recruited to obtain 90% power to detect a four-point difference in OKS between the groups one year after surgery, assuming up to 40% resurfacing in the selective group. The trial findings will provide evidence about the clinical and cost-effectiveness of always patellar resurfacing compared to selective patellar resurfacing. This will inform future NICE guidelines on primary TKR and the role of selective patellar resurfacing.

Barriers and enablers to the implementation and sustainability of short-stay arthroplasty programs for elective primary total hip and knee replacement: A systematic review with qualitative evidence synthesis.

We aimed to systematically review contemporary evidence on the barriers and enablers to implementing and sustaining short-stay arthroplasty programs for elective primary total hip and knee replacement from the perspectives of patients, health professionals, carers, healthcare administrators, funders and policymakers and to map the findings to the Theoretical Domains Framework (TDF). Medline, Cumulative Index to Nursing and Allied Health Literature, EMBASE, and the Cochrane Central Register of Controlled Trials were searched (up to 19 August 2023). Primary qualitative or mixed-methods studies reporting on perspectives relating to the review aims that utilised a short-stay programme were eligible for inclusion. Study quality was assessed using the qualitative critical appraisal tool from the Joanna Briggs Institute. Data were analysed inductively. The final themes were mapped to the TDF. The confidence in the findings was assessed using GRADE CERQual. Fifteen studies were included. Twelve barrier themes and twelve enabler themes were identified. Three themes were graded with high confidence, 10 were graded with moderate confidence, three were graded with low confidence, and eight were graded with very low confidence. The most pertinent domains that the themes were mapped to for patients were beliefs about capabilities, reinforcement, and the environmental context and resources. Health professionals identified knowledge, environmental context and resources as important domains. Two domains were identified for carers: (1) social/professional role and identity and (2) memory, attention, and decision processes. We identified key barrier and enabler themes linked to the TDF that can be used to guide implementation initiatives and promote the sustainability of short-stay arthroplasty programs.

Identifying pulmonary embolism - high risk patients after total knee replacement: systematic review.

To determine the incidence, onset, risk factors and mortality of pulmonary embolism in total knee replacement patients. The systematic review was conducted in September 2022, and comprised search on PubMed, ScienceDirect, Scopus and Crossref databases for studies published from 1977 till September 7, 2022, in the English language related to the incidence of pulmonary embolism after primary total knee replacement. Cochrane Handbook for Systematic Reviews of Interventions was used to assess risk of bias, and the Newcastle-Ottawa Scale was used to assess the quality of evidence. Of the 3,910 studies initially identified, 66(1.68%) were analysed in detail, which together had 13,258,455 total knee replacement patients. Pulmonary embolism was reported in 76,515(0.58%) cases. The onset of pulmonary embolism ranged 2-150 days post-surgery. Patients with older age, diabetes mellitus, higher body mass index, atrial fibrillation, previous venous thromboembolism, high Charlson Comorbidity Index score, hypertension, arrhythmia and chronic heart failure were at significantly higher risk (p<0.05). The overall mortality rate of pulmonary embolism in such cases ranged 10.53-100%. Pulmonary embolism is a rare complication after orthopaedic surgery, but it has a very high mortality rate. By recognising the risk factors, attending physicians can optimise the use of chemoprophylaxis, thus preventing pulmonary embolism.

Enhancing recovery and reducing readmissions: The impact of remote monitoring on acute postoperative care in outpatient total joint arthroplasty

IntroductionOutpatient total joint arthroplasty (TJA) is gaining popularity in the United States. With a shift towards value-based healthcare and bundled payment models, the importance of safe discharge after TJA is pertinent in reducing readmissions and subsequent cost of care. However, many acute issues or complications may not occur until after discharge which can result in emergency department visits and readmission. Our study aims to characterize the effect of remote monitoring devices on acute postoperative recovery in TJA discharged within 24 h. We hypothesized there would be a decreased readmission rate in the remote home monitoring cohort. MethodsThis prospective cohort compared 50 outpatient TJAs (primary total hip and total knee replacements) defined as discharged within 24 h with a remote home monitoring device to 50 outpatient TJAs who did not receive remote monitoring. Demographics, hospital length of stay, American Society of Anesthesiology scores, and Charlson Comorbidity Index were compared with no significant difference observed between cohorts (p > 0.05). Patients’ vital signs were transmitted to a virtual response center for up to 48 h after discharge. An on-call medical team reviewed the transmissions and if prompted, would contact the patient to troubleshoot and triage. Primary outcome was 30-day hospital readmissions rates, while 30-day ED visits and patient satisfaction scores for the remote home monitoring were measured as secondary outcomes. ResultsWithin the remote monitoring cohort there was a 20 % incidence (10 patients) of abnormal vitals captured and 2 patients visited the ED, however there were no readmissions attributed to this group. Readmission rates and ED visits in the control non-monitored group were significantly higher at 12 % (p = 0.03), secondary to syncope, uncontrolled postoperative pain, cellulitis, hip dislocations, and postoperative fever. Of the patients who received remote monitoring, 14 % had trouble connecting the device to their smartphone, 44 % felt home monitoring helped in their care while recovering at home, 52 % made them feel safer, and 70 % would recommend this program. ConclusionsRemote home monitoring with a virtual response team after outpatient TJA is a feasible way to mitigate readmissions in the acute postoperative period and increase patient satisfaction. Efforts to minimize costs should not be implemented at the expense of patients’ health outcomes with a goal to find an appropriate balance between both agendas. Level of evidenceTherapeutic Level III.

Preoperative MRSA screening using a simple questionnaire prior elective total joint replacement.

The purpose of this study was to evaluate the management and results of our standarized protocol for preoperative identification of MRSA colonisation in patients undergoing primary total hip and knee replacement procedures. Following hospital protocol, between January 2016 and June 2019 37,745 patients awaiting elective joint replacement underwent a standardized questionnaire to assess the risk of MRSA infection, identifying patients requiring preoperative MRSA screening. An evaluation of the questionnaire identified effective questions for identifying infected patients. Furthermore, an analysis evaluated the impact of comorbidities or Charlson Comorbidity Index scores on positive MRSA colonization. Additionally, we evaluated the cost savings of targeted testing compared to testing all surgery patients. Of the 37,745 patients, 8.057 (21.3%) were swabbed, with a total of 65 (0.81%) positive tests. From this group 27 (36.48%) who were treated were negative before surgery. Some of the questionnaire results were consistently associated with a higher chance of colonization, including hospitalization during the past year (47,7%), previous history of MRSA (44,6%), and agriculture or cattle farming related work (15,4%). By selectively testing high-risk patients identified through the questionnaire, we achieved a 79% reduction in costs compared to universal MRSA screening. Our results suggest that the simple and standardized questionnaire is a valuable tool for preoperative screening, effectively identifying high-risk patients prone to MRSA colonisation. The risk of periprosthetic joint infection (PJI) and its associated sequelae may be reduced by this approach.

The functional and psychological impact of delayed hip and knee arthroplasty: a systematic review and meta-analysis of 89,996 patients

This systematic review and meta-analysis aimed to determine the impact of presurgical waiting times on pre-/post-operative joint specific pain and function, health-related quality of life (HRQOL) and perspectives of patients awaiting primary elective total hip (THR) and knee (TKR) replacements. MEDLINE, EMBASE, PUBMED, and CENTRAL databases were searched from inception until 30th January 2023 (CRD42022288128). Secondary literature and unpublished datasets containing paediatric, non-elective, partial, or revision replacement populations were excluded. PRISMA 2020 reporting and GRADE certainty of evidence guidelines were followed. Residual maximum likelihood meta-analysis and linear meta-regression was performed to elucidate the influence of presurgical waiting time. Twenty-six studies were eligible for systematic review and sixteen for meta-analysis, capturing 89,996 patients (60.6% female, mean age 67.4 years) between 2001 and 2022. A significant deterioration in joint function (mean difference (MD):0.0575%; 95% CI 0.0064, 0.1086; p = 0.028(4d.p.); I2 = 73.1%) and HRQOL (MD: 0.05%; 95% CI − 0.0001.0009; p = 0.011(4 d.p.); I2 = 80.6%) was identified per additional day of waiting. Despite qualitative evidence, meta-analysis could not observe a relationship with postoperative outcome data. Patient responses to delayed THR and TKR surgery were unanimously negative. Immediate action should seek to reduce the increased patient anxiety and significant reductions in pre-operative joint functionality and HRQOL associated with prolonged pre-surgical waiting time, whilst mitigating any potential deleterious post-operative effects.

The Effect of Valgus Deformity Degree of Knee Osteoarthritis Patients on Tibiofemoral Angle Mechanical Output and Knee Society Score After Total Knee Arthroplasty Non-Constrained at Prof. Dr. I.G.N.G Ngoerah Hospital

Background: Osteoarthritis (OA) is a progressive musculoskeletal problem causing a loss of articular cartilage and damage to cellular and biomechanical components. In Indonesia, the prevalence of OA is 36.5 million people, with 40% over 70 years old and 80% with limited movement. Malalignment in the knee joint, found in almost 10% of patients undergoing total knee arthroplasty (TKA) surgery, is a challenge for orthopedic surgeons. Factors such as body weight, high BMI, work history, malalignment, and synovitis are associated with the development of knee OA. Total Knee Arthroplasty (TKA) is a surgical procedure to overcome OA problems in the knee joint, but deformities affect the success of TKA surgery. Researchers aim to determine if there is an association between valgus deformity in knee OA patients and tibiofemoral angle correction and Knee Society Score 12 weeks after TKA. Methods: The study involved 42 patients with primary knee osteoarthritis and valgus deformity who underwent primary Total Knee Replacement (TKR) at Prof. Dr. Ngoerah Hospital. The study included patients with grade III-IV Kellgren-Lawrence knee osteoarthritis, underwent primary TKA, and had lower extremity scans before and 12 weeks postoperatively. Functional and clinical outcomes were measured using mechanical tibiofemoral angle and Knee Severity Score. Results: The study involved 21 female patients with OA Ranawat 2 and a 7:1 ratio of male and female participants. The most common OA was in the right knee. After TKR, there was no significant difference in MTFA and KSS scores between patients. However, after 12 weeks, the average MTFA score decreased to 8.57, with a significant change before and after the surgery. Keywords: Osteoarthritis, total knee arthroplasty (TKA), Kellgren-Lawrence.

Item Response Theory Validation of the Forgotten Joint Score for Persons Undergoing Total Knee Replacement.

The Forgotten Joint Score (FJS), a commonly used patient-reported outcome measure, was developed without fully confirming assumptions such as unidimensionality (all items reflect 1 underlying factor), appropriate weighting of each item in scoring, absence of differential item functioning (in which different groups, e.g., men and women, respond differently), local dependence (pairs of items are measuring only 1 underlying factor), and monotonicity (persons with higher function have a higher score). We applied item response theory (IRT) to perform validation of the FJS according to contemporary standards, and thus support its ongoing use. We aimed to confirm that the FJS reflects a single latent trait. In addition, we aimed to determine whether an IRT model could be fitted to the FJS. Participants undergoing primary total knee replacement provided responses to the FJS items preoperatively and at 6 and 12 months postoperatively. An exploratory factor analysis (EFA), confirmatory factor analysis (CFA), and Mokken analysis were conducted. A graded response model (GRM) was fitted to the data. A total of 1,774 patient responses were analyzed. EFA indicated a 1-factor model (all 12 items reflecting 1 underlying trait). CFA demonstrated an excellent model fit. Items did not have equal weighting. The FJS demonstrated good monotonicity and no differential item functioning by sex, age, or body mass index. GRM parameters are reported in this paper. The FJS meets key validity assumptions, supporting its use in clinical practice and research. The IRT-adapted FJS has potential advantages over the traditional FJS: it provides continuous measurements with finer granularity between health states, includes individual measurement error, and can compute scores despite more missing data (with only 1 response required to estimate a score). It can be applied retrospectively to existing data sets or used to deliver individualized computerized adaptive tests. Prognostic Level II . See Instructions for Authors for a complete description of levels of evidence.

Effect of Intravenous Zoledronic Acid on Total Knee Replacement in Patients With Symptomatic Knee Osteoarthritis and Without Severe Joint Space Narrowing: A Prespecified Secondary Analysis of a Two-Year, Multicenter, Double-Blind, Placebo-Controlled Clinical Trial.

To determine the effect of zoledronic acid (ZA) on the risk of total knee replacement (TKR) in patients with symptomatic knee osteoarthritis and without severe joint space narrowing (JSN). We included 222 participants (mean age 62 years, 52% female) from the two-year Zoledronic Acid for Osteoarthritis Knee Pain trial (113 received 5 mg of ZA annually and 109 received placebo) conducted between November 2013 and October 2017. Primary TKR were identified until February 22, 2022. The effect of ZA on TKR risk was evaluated using Cox proportional hazard regression models. Because the treatment effect failed the proportional hazards assumption, a time-varying coefficients analysis for treatment was conducted by splitting the study into two periods (ie, within and after two years of randomization). Over a mean follow-up of seven years, 39% and 30% of participants had any TKR in the ZA and placebo groups, and 28% and 18% had TKR in the study knee, respectively. Use of ZA was associated with a higher risk of TKR in any knee (hazard ratio [HR] 4.2, 95% confidence interval [CI] 1.2-14.7) and showed a trend in the study knee (HR 6.8, 95%CI 0.9-53.9) during the trial. In the posttrial period, the risk of TKR was similar in the ZA and the placebo groups for any knee (HR 1.2, 95%CI 0.5-1.8) and the study knee (HR 1.4, 95%CI 0.5-2.2). These results suggest that ZA is not protective against TKR in patients with symptomatic knee osteoarthritis and without severe JSN.

Arthroscopic debridement improves range of motion for heterotopic ossification after total knee replacement: a retrospective cohort study

The presence of heterotopic ossification (HO) after primary total knee replacement (TKR) is rare and associated with limited mobility and stiffness of the knee. This study aimed to identify if the arthroscopic debridement after TKR could decrease HO and improve the function and range of motion. Thirty HO patients after TKR were retrospectively separated into 2 cohorts. 15 patients of group A accepted the arthroscopic debridement, while 15 patients of group B only had non-operative treatment, mainly including oral nonsteroidal anti-inflammatory drugs (NSAIDs) and rehabilitative treatment. Visual analog scale (VAS) scores, knee society knee scores (KSS), range of motion (knee flexion and knee extension) were obtained before treatment and at 1 month, 3 months, and 6 months after treatment. Radiography of after-treatment was also evaluated to assess the changes in HO. There were 3 males and 27 females with a mean age of 67.4 ± 0.8 years in group A and 68.2 ± 1.3 in group B. The onset time of HO was 3–6 months. The maximum size of the ossification was < 2 cm in 23 knees, 2 cm < heterotopic bone < 5 cm in 6 knees and > 5 cm in 1 knee. The size of HO decreased gradually in all knees by X-ray film at the last follow-up. There were no significant differences in VAS scores after replacement between two groups (p > 0.05). The average range of motion preoperatively in group A was − 15.2–90.6°, which postoperatively increased to − 4.2–110.0°. Meanwhile, the KSS scores and average range of motion of the group A were better than those of the group B at each follow-up time after treatment. Arthroscopic debridement can decrease HO seen from postoperative X-rays, improve the function and range of motion, as well as the pain remission between two groups are comparable. Consequently, arthroscopic resection of HO after TKR is recommended as soon as there is aggravating joint stiffness.

Using the Stratum-Specific Likelihood Ratio Method to Derive Outcome-Based Hospital Volume Categories for Total Knee Replacement.

Evidence of higher hospital volume being associated with improved outcomes for patients undergoing total knee replacement (TKR) is mostly based on arbitrary distribution-based thresholds. We aimed to define outcome-based volume thresholds using data from a national database. We used the MedPAR Limited Data Set inpatient data from 2010-2015 to identify patients who had undergone primary TKR. Surgical and TKR specific complications occurring within the index hospitalization and all-cause readmission within 90 days were considered adverse events. We derived an average annual TKR case volume for each hospital and applied the stratum-specific likelihood ratio method to determine volume categories indicative of a similar likelihood of 90-day post-operative complications. Hierarchical multivariable logistic regression with a random intercept for hospital nested within study year and adjusted for patient and hospital characteristics was performed to determine if these volume thresholds were still associated with the odds of 90-day readmission for complications after adjustment. SSLR analysis yielded 4 hospital volume categories based on the likelihood of 90-day postoperative complications: 1-31 (low), 32-127 (medium), 128-248 (high), and 429+ (very high) TKRs performed per year. The results of the hierarchical multivariable logistic regression showed significantly increased odds of 90-day complications at lower volume categories. Sensitivity analyses confirmed our main findings. This study is the first to provide national-level volume categories that are evidence-based. Publicizing these thresholds may enhance quality measures available to patients, providers, and payors.

The impact of primary total hip and knee replacement on frailty: an observational prospective analysis

BackgroundOsteoarthritis is a prevalent condition in frail older adults that requires hip or knee replacement in many patients. The aim of the study was to determine the impact of hip and knee arthroplasty on frailty.MethodsIn this prospective short-term study, we used data from 101 participants of the ongoing Special Orthopaedic Geriatrics (SOG) trial, funded by the German Federal Joint Committee (GBA). Frailty, measured by Fried’s Physical Frailty Phenotype (PFP), was assessed preoperatively, 7 days postoperatively, 4–6 weeks and 3 months after hip and knee arthroplasty. ANOVA with repeated measures and post-hoc tests for the subgroups were used for the statistical analysis.ResultsOf the 101 participants, 50 were pre-frail (1–2 PFP criteria) and 51 were frail (≥ 3 PFP criteria) preoperatively. In the pre-frail group, the PFP score decreased from 1.56 ± 0.50 (median 2) preoperatively to 0.53 ± 0.73 (median 0) 3 months after surgery (p < 0.001). The PFP score in the frail cohort decreased from 3.39 ± 1.45 (median 3) preoperatively to 1.27 ± 1.14 (median 1) 3 months postoperatively (p < 0.001). While the PFP score of the pre-frail participants increased 7 days after surgery, the PFP score of the frail group decreased significantly.ConclusionPre-frail individuals often regain robustness and patients with frailty are no longer assessed as frail after surgery. Joint replacement is an effective intervention to improve frailty in hip and knee osteoarthritis.Trial registrationThis study is part of the Special Orthopaedic Geriatrics (SOG) trial, German Clinical Trials Register DRKS00024102. Registered on 19 January 2021.

Total knee replacement in different age groups

To evaluate the efficacy and quality of life in long-term period (1 year) after total knee replacement in various age groups. We studied 134 patients after unilateral primary total knee replacement. The KOOS and SF-36 questionnaires were used to assess the therapeutic effect (functionality and symptoms) and quality of life in patients with knee osteoarthritis. At baseline, group I (young patients) had low KOOS pain scores (39.42±16.42), function scores (50.18±19.16) and QoL scores (18.2±15.9) compared to other age groups. A year after surgery, group I (<55 years) had significantly lower KOOS scores of pain, function and quality of life compared to group III (>65 years). Multiple regression analysis showed that age was a significant predictor of pain, but not a function after a year. Total knee replacement gives a noticeable improvement in pain, functionality and quality of life in all age groups. However, there are significant age-related differences in preoperative assessment of pain, quality of life and mental health, as well as in final indicators of postoperative pain and quality of life. Indeed, young patients (<50 years) report more intense pain and worse quality of life. These data may be used in clinical practice to improve decision-making and patient expectations before total knee replacement.

Functional Outcome of Subvastus versus Medial Parapatellar Approaches for Total Knee Replacement in Patients with Knee Osteoarthritis: A Prospective Cohort Study.

Subvastus approach and medial parapatellar approach are two major approaches for total knee replacement (TKR). There is no global consensus on the superiority of either approach in terms of functional outcomes. The present study aimed to evaluate the functional outcome of TKR through subvastus approach and medial parapatellar approach by using patient-reported scores at 3-, 6-, and 12-month post-operative follow-ups. This prospective cohort follow-up study included patients with knee osteoarthritis who underwent elective primary TKR either through the subvastus or medial parapatellar approaches at King Abdullah Medical City, Makkah city, Kingdom of Saudi Arabia, from January 2019 to December 2022. Scores from the self-reported Oxford Knee Score (OKS) and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were compared in the two groups of patients at 3-, 6-, and 12-month post-operative follow-ups. A total of 98 patients were included, of which 37 underwent TKR through the subvastus approach and 61 through the medial parapatellar approach. There was an overall significant change over time in both WOMAC and OKS scores (P < 0.001). Patients who underwent the subvastus approach had significantly higher mean of WOMAC and OKS than patients with the medial parapatellar approach at the 3- and 6-month follow-ups (P < 0.05), but not at the 12-month follow-up. For TKR, the medial parapatellar approach results in better functional outcomes at the 3- and 6- month follow-up periods compared with the subvastus approach.

Increased risk of aseptic loosening for posterior stabilized compared with posterior cruciate-retaining uncemented total knee replacements: a cohort study of 13,667 knees from the Dutch Arthroplasty Registry

Background and purpose: While registry studies have suggested a higher risk of revision for posterior-stabilized (PS) compared with posterior cruciate-retaining (CR) total knee replacements (TKR) using cement, it is unknown whether this is also the case for uncemented TKR. We aimed to compare the revision rates of PS and CR designs in patients receiving primary uncemented TKR.Patients and methods: Data from the Dutch arthroplasty register (LROI) was analyzed, comprising 12,226 uncemented primary CR TKRs and 750 uncemented PS TKRs registered between 2007 and 2022. Competing risk and multivariable Cox regression analyses were used to compare revision rates, risks of revision, and reasons for revision between groups. Sensitivity analyses were performed to analyze the risk, concerning the 5 most commonly used implants and performing hospitals for each group.Results: Uncemented PS TKRs had higher 10-year revision rates for any reason and aseptic loosening (6.5%, 95% confidence interval [CI] 4.6–9.2 and 3.9%, CI 2.6–6.7) compared with uncemented CR TKRs (4.2%, CI 3.8–4.7 and 1.4%, CI 1.2–1.7). PS TKRs were 1.4 and 2.5 times more likely to be revised for any reason and aseptic loosening, respectively. These results remained consistent after adjustment for age, sex, BMI, previous surgeries, bearing mobility, and surface modification, with sensitivity analyses.Conclusion: We found that uncemented PS implants have a higher rate of revision than uncemented CR implants, mainly due to a higher risk of aseptic loosening.

When to Do Selective Patellar Resurfacing in Total Knee Arthroplasty: A Decision-Making Algorithm Based on Pre-operative and Intra-operative Findings.

Persistent anterior knee pain post total knee arthroplasty (TKA) is a significant cause of patient dissatisfaction. Selective patellar resurfacing is commonly practiced for primary total knee replacement (TKR) but there is a paucity in literature regarding its decision making. This study aims to develop a decision-making algorithm for selective patellar resurfacing using Hospital for Special Surgery Patello-femoral Assessment score (HSS PFA score), weight-bearing patellofemoral X-ray, and intraoperative cartilage wear assessment based on the Outerbridge classification. This prospective study enrolled 65 patients, assessing preoperative factors including HSS PFA score and Baldini view radiography. Intraoperative cartilage wear was categorized using the Outerbridge classification. Preoperative findings were correlated with intraoperative outcomes through statistical analysis, leading to the development of a predictive algorithm. The efficiency of algorithm was assessed at 3-year follow-up using HSS PFA score. A significant negative correlation (r = -0.272, p = 0.029) was observed between HSS PFA score and cartilage wear. However, no significant relationships were established between HSS PFA score and Baldini view observations, including radiological tilt (p = 0.517) and displacement (p = 0.277). Intraoperative cartilage wear versus patellar tilt (p = 0.65) and displacement (p = 0.837) also yielded non-significant results. Three-year follow-up examinations revealed no complications and significant HSS PFA score improvements in all patients. The requirement for patellar resurfacing can be predicted using a combination of preoperative parameter such as HSS PFA score and the intra-operative cartilage wear. We put forward an algorithm based on above findings to aid in the decision making.

6-month migration sufficient for evaluation of total knee replacements: a systematic review and meta-analysis.

This updated meta-analysis evaluates the migration pattern of the tibial component of primary total knee replacements measured with radiostereometric analysis (RSA). We aimed to evaluate whether 6-month maximum total point motion (MTPM) values could be used instead of 1-year MTPM for RSA threshold testing and to present the pooled migration patterns for different implant designs that can be used as a benchmark. The search included all published RSA studies on migration patterns of tibial components until 2023. Study groups were classified according to their prosthesis brand, fixation, and insert (PFI). Sub-analyses were performed to compare the mean tibial component migration patterns of different implant variables, stratified according to fixation. 96 studies (43 new studies), including 197 study groups and 4,706 knees, were included. Most migration occurred within the first 6 postoperative months (126 study groups: mean 0.58 mm, 95% confidence interval [CI] 0.50-0.65), followed by minimal migration between 6 and 12 months (197 study groups: mean 0.04 mm, CI 0.03-0.06), irrespective of the fixation method used. Distinct migration patterns were observed among the different fixation methods. No differences were found in migration patterns among cemented components in any of the sub-group analyses conducted. For uncemented implants, trabecular metal surfaced components seemed to migrate less than porous-coated or uncoated components Conclusion: Based on the small difference between MTPM values at 6 months and 1 year, MTPM at 6 months could be used instead of MTPM at 1 year for RSA threshold testing. The pooled migration patterns can be used as benchmark for evaluation of new implants by defining fixation-specific RSA thresholds when combined with implant survival.

Impact of Hepatitis B on Complications and Functional Outcomes in Patients Undergoing TKR.

In India, infected patients with hepatitis B virus (HBV) undergoing total knee replacement (TKA) are increasing. It is recognized that patients with HBV infection are more susceptible to complications after surgery. To evaluate the effect of HBV infection on complications and functional outcome after TKA was the aim of this study. This is the retrospective observation analysis of patients who underwent primary total knee replacement in our hospital from 2017 to 2019. A total of 92 patients were included in the study, of which 46 patients were asymptomatic HBV-positive, and these 46 patients were compared with a matched cohort of another 46 patients who were non-HBV. A total of 92 patients were analyzed (asymptomatic HBV n = 46, non-HBV n = 46). The incidence rate of total complications in patients undergoing TKA with asymptomatic HBV was 19.57% compared to 4.3% in non-HBV (p < 0.001). Applied with regression models, patients with HBV had an 8.6% increased risk of surgical complication which included one peri-prosthetic joint infection, three wound dehiscence compared with the non-HBV group which had 2.17% surgical complications (one wound dehiscence). Medical complications were higher in asymptomatic HBV group with 10.87% (which includes one pulmonary embolism, two DVT, and two strokes). In comparison with the non-HBV group which had 2.17% medical complications (one DVT), asymptomatic HBV group had 5.35-fold (95% CI 1.09-26.33; p < 0.01) increase in overall complications. Post-TKA surgical complications are 4.29-fold (95% CI 0.46-39.91; p < 0.01) higher compared to non-HBV group. Our study showed asymptomatic hepatitis B patients are at an increased risk of complications (peri-prosthetic joint infections and wound dehiscence) compared to normal patients. In hepatitis B and non-hepatitis B patients, functional outcomes in terms of OKS are comparable.

RISK OF REVISION FOLLOWING TOTAL HIP AND KNEE ARTHROPLASTY PERFORMED USING COMPUTER-ASSISTED TECHNOLOGIES VERSUS CONVENTIONAL TECHNIQUE: AN ANALYSIS OF NATIONAL JOINT REGISTRY DATA

AbstractIntroductionComponent mal-positioning in total hip replacement (THR) and total knee replacement (TKR) can increase the risk of revision for various reasons. Compared to conventional surgery, relatively improved accuracy of implant positioning can be achieved using computer assisted technologies including navigation, patient-specific jigs, and robotic systems. However, it is not known whether application of these technologies has improved prosthesis survival in the real-world. This study aimed to compare risk of revision for all-causes following primary THR and TKR, and revision for dislocation following primary THR performed using computer assisted technologies compared to conventional technique.MethodsWe performed an observational study using National Joint Registry data. All adult patients undergoing primary THR and TKR for osteoarthritis between 01/04/2003 to 31/12/2020 were eligible. Patients who received metal-on-metal bearing THR were excluded. We generated propensity score weights, using Sturmer weight trimming, based on: age, gender, ASA grade, side, operation funding, year of surgery, approach, and fixation. Specific additional variables included position and bearing for THR and patellar resurfacing for TKR. For THR, effective sample sizes and duration of follow up for conventional versus computer-guided and robotic-assisted analyses were 9,379 and 10,600 procedures, and approximately 18 and 4 years, respectively. For TKR, effective sample sizes and durations of follow up for conventional versus computer-guided, patient-specific jigs, and robotic-assisted groups were 92,579 procedures over 18 years, 11,665 procedures over 8 years, and 644 procedures over 3 years, respectively. Outcomes were assessed using Kaplan-Meier analysis and expressed using hazard ratios (HR) and 95% confidence intervals (CI).ResultsFor THR, analysis comparing computer-guided versus conventional technique demonstrated HR of 0.771 (95%CI 0.573–1.036) p=0.085, and 0.594 (95%CI 0.297–1.190) p=0.142, for revision for all-causes and dislocation, respectively. When comparing robotic-assisted versus conventional technique, HR for revision for all-causes was 0.480 (95%CI 0.067 –3.452) p=0.466. For TKR, compared to conventional surgery, HR for all-cause revision for procedures performed using computer guidance and patient-specific jigs were 0.967 (95% CI 0.888–1.052) p=0.430, and 0.937 (95% CI 0.708–1.241) p=0.65, respectively. HR for analysis comparing robotic-assisted versus conventional technique was 2.0940 (0.2423, 18.0995) p = 0.50.ConclusionsThis is the largest study investigating this topic utilising propensity score analysis methods. We did not find a statistically significant difference in revision for all-causes and dislocation although these analyses are underpowered to detect smaller differences in effect size between groups. Additional comparison for revision for dislocation between robotic-assisted versus conventionally performed THR was not performed as this is a subset of revision for all-causes and wide confidence intervals were already observed for that analysis. It is also important to mention this NJR analysis study is of an observational study design which has inherent limitations. Nonetheless, this is the most feasible study design to answer this research question requiring use of a large data set due to revision being a rare outcome.Declaration of Interest(b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

TRAINING IN HIP AND KNEE ARTHROPLASTY: ARE THEY DOING ENOUGH?

Orthopaedic surgery is a practical surgical specialization field, the exit exam for registrars remains written and oral. Despite logbook evaluation and surgical work-based assessments, the question remains: can registrars perform elective surgery upon qualification? In South Africa, obstacles to elective surgical training include the trauma workload, financial constraints, fellowships and the Covid pandemic. In hip and knee arthroplasty, new approaches like the direct anterior approach (DAA) and robotic-assisted knee surgery also contributed to the dilution of cases available for registrar training. There are concerns that orthopaedic registrars do not perform enough cases to achieve surgical proficiency.Review of the last 4 years of registrar logbooks in hip and knee arthroplasty surgery performed in a single tertiary academic hospital in South Africa. We included all primary total hip replacements (THR), total knee replacements (TKR) and hemiarthroplasties (HA) done for neck of femur (NOF) fractures between 1 April 2019 and 30 March 2023. Differentiation between registrar assisting, registrar performing with consultant supervision and registrar performing independent surgery was done.990 hip arthroplasties (472 Primary THR, 216 NOF THR, 302 NOF HA) and 316 Primary TKR were performed during the study period. In primary elective THR the posterior approach was dominant and used in 76% of cases. In NOF THA the DAA was dominant used in 98% of cases. Primary TKR robotic-assisted technologies was used in 27% (n=94) cases. Registrars as the primary surgeon were the highest in NOF THA at 70% of cases and the lowest performing TKR at 25%. During 3-month rotations, an average registrar performed 12 (2 TKR and 10 THR) and assisted in 35 (10 TKR and 25 THR) cases.Despite the large number of arthroplasties operations being performed over the last 4-year period, the surgical cases done by registrars are below, the proposed minimal cases to provide surgical proficiency during their training period.