Abstract Background Hypermobile lateral meniscus (HLM) causes lateral knee pain and mechanical symptoms, but preoperative identification remains challenging because HLM is a dynamic abnormality that is not always captured on static magnetic resonance imaging (MRI). Previous MRI-based studies have mainly focused on linear measurements or qualitative popliteomeniscal fascicle (PMF) abnormalities. This study aimed to evaluate whether spatial MRI assessment beyond conventional linear distance measurements could help characterize arthroscopically confirmed HLM. We also aimed to determine whether MRI-derived markers could be organized into a clinically interpretable MRI-based approach to raise preoperative suspicion for HLM. Methods This retrospective study included patients who underwent knee MRI followed by arthroscopic assessment of lateral meniscal stability. After propensity score matching, 53 knees with arthroscopically confirmed HLM and 53 non-HLM surgical controls were analyzed. MRI-derived variables included LM–popliteal tendon distance, region-of-interest-based measurement, MRI signal intensity ratio, and PMF integrity. Each PMF was evaluated separately and then summed to obtain the combined PMF score. Firth’s logistic regression, receiver operating characteristic curve, and Youden index analysis were performed. Results Static measurements of LM–popliteal tendon separation did not differ between groups. In contrast, the sagittal MRI signal intensity ratio (odds ratio [OR], 1.067; 95% confidence interval [CI] 1.012–1.137; p = 0.044) and the combined PMF score were significantly associated with HLM (OR, 0.098; 95% CI 0.034–0.257; p < 0.001) were significantly associated with HLM in univariable analysis. In multivariable analysis, only the combined PMF score remained independently associated with HLM. The PMF score-only model showed an area under the curve of 0.794 (95% CI 0.709–0.879), with a Youden-derived threshold of ≤ 1.0, sensitivity of 58.5%, specificity of 86.8%, and accuracy of 72.6%. Conclusions The combined PMF score was the MRI-derived marker most consistently associated with arthroscopically confirmed HLM. In this selected surgical cohort, lower combined PMF scores showed acceptable discrimination and relatively high specificity, although sensitivity was modest. Accordingly, a combined PMF score of ≤ 1.0 may provide adjunctive MRI information that raises suspicion for HLM when the clinical presentation is suggestive, but it cannot exclude HLM or independently establish the diagnosis, and the decision to perform arthroscopy should not be based on the score alone. Arthroscopic dynamic assessment remains necessary for definitive confirmation.
Abstract Purpose We aimed to investigate long-term outcomes and factors associated with revision after medial open-wedge high tibial osteotomy (OWHTO) according to Kellgren–Lawrence (KL) grade. Methods This retrospective study included 274 knees (158 KL grade 4 [KL4] knees and 116 KL grades 2–3 [KL2–3] knees; mean age 64.7 ± 7.2 years) with a minimum follow-up of 10 years (mean follow-up, 12.5 ± 2.6 years) after OWHTO. Revision surgery (conversion to total knee arthroplasty [TKA] or unicompartmental knee arthroplasty [UKA]) was defined as the endpoint. Clinical and radiographic outcomes were evaluated. Multivariate logistic regression analyses were performed separately for KL4 and KL2–3 knees to identify factors associated with revision. Results The mean Japanese Orthopaedic Association (JOA) score improved from 60.6 preoperatively to 91.0 at plate removal, followed by gradual deterioration during long-term follow-up. Final JOA scores were significantly lower in KL4 knees than in KL2–3 knees (71.6 versus 83.1; p < 0.001). Revision surgery was performed in 43 knees (15.7%) and was significantly more frequent in KL4 than in KL2–3 knees (22.2% versus 6.9%; p < 0.01). Ten-year joint preservation rates were 90.5% in KL4 knees and 96.5% in KL2–3 knees (log-rank p = 0.006). In KL4 knees, postoperative percentage mechanical axis (%MA) at the time of plate removal was independently associated with revision risk (odds ratio [OR] 0.94, 95% confidence interval [CI] 0.91–0.98; p = 0.004). In KL2–3 knees, an exploratory multivariate analysis suggested an association between progression of joint line convergence angle during follow-up (ΔJLCA) and revision (OR 3.31, 95% CI 1.52–7.21; p = 0.003), whereas postoperative %MA showed no significant association. Conclusions Long-term outcomes after OWHTO differed according to KL grade. KL4 knees demonstrated higher revision rates and inferior joint preservation survival, and postoperative weight-bearing line position was associated with revision risk. In contrast, revision was uncommon in KL2–3 knees, and exploratory analysis suggested a possible association with longitudinal changes in joint line convergence rather than postoperative alignment. These findings suggest that factors associated with revision may differ according to disease severity. Level of evidence This was a level IV, retrospective cohort study.
To identify and describe the prognostic factors associated with outcomes after knee cartilage repair within distinct procedure and disease contexts. PubMed, Embase, the Cochrane Library, and Google Scholar were searched from inception to 29 August 2026; backward and forward citation searching was also performed. Eligible reports quantitatively evaluated baseline factor–postoperative outcome associations after knee cartilage repair. Two reviewers independently selected reports, extracted association-level data, and applied the quality in prognosis studies tool. Because effect measures could not be harmonized, findings were synthesized without meta-analysis by disease context, procedure, factor, outcome, and follow-up. Thirty-one reports were included, with report-level sample sizes totaling 13,022; cohort overlap prevented determination of the number of unique participants. Of 37 study–analysis units, 29 were at high risk-of-bias and 8 at moderate risk; none were at low risk. In isolated marrow stimulation, increasing age was associated with less favorable short- and long-term outcomes in two multivariable analyses at high overall risk-of-bias, whereas lesion-size findings varied across outcomes and follow-up. Autologous chondrocyte implantation (ACI)/matrix-induced autologous chondrocyte implantation (MACI) studies reported outcome-specific associations involving age, sex, body mass index, baseline status, defect characteristics, previous surgery, and manufacturing variables. Adjusted osteochondral-allograft failure analyses identified age, body mass index, diagnosis, graft area, and bony realignment as candidate factors; clinical-threshold and machine-learning findings remained context dependent. In osteoarthritis-associated cell-based cohorts, older age and bipolar lesions were associated with long-term failure in one adjusted analysis, while other findings were imprecise or derived from overlapping cohorts. No factor was consistently established across procedures or outcomes. A formal certainty-of-evidence framework was not applied because of marked heterogeneity, sparse context-specific evidence, and generally high risk-of-bias; definitive between-procedure comparisons were not possible. Available evidence identifies candidate prognostic associations within specific disease, procedure, outcome, and follow-up contexts. However, substantial clinical heterogeneity, potential confounding, cohort overlap, and sparse context-specific evidence limit the certainty and generalizability of the findings. The evidence does not support universal clinical cutoffs or conclusions that prognostic effects differ between procedures. Level of evidence: level IV, systematic review of level I–IV studies.
Abstract Background To date, two studies have established the correlation between jumping sign and multiple bony abnormalities. However, no studies have yet reported the association between the jumping sign and clinical outcomes. Purpose (1) To determine the bony risk factors of jumping patella and (2) to compare clinical outcomes between jumping and gliding patellae following medial patellofemoral ligament (MPFL) reconstruction. Patients and methods Between 2018 and 2022, 85 patients with recurrent patellar dislocation (RPD) who underwent MPFL reconstruction were retrospectively reviewed. Patients were stratified into two groups based on the presence or absence of the preoperative patellar jumping sign. Standard hip-knee-ankle computed tomography (CT) scans were obtained for all patients, through which lower limb torsional deformities and bony morphology were evaluated. Bony risk factors for preoperative jumping patella were identified using logistic regression analysis. Clinical outcomes were compared between groups at final follow-up. Subgroup analyses were conducted to examine outcome differences between surgical procedures within each patellar tracking group. Results This study included a total of 85 patients, with 36 cases in the jumping group. Multivariate regression analysis identified knee torsion (odds ratio [OR] = 7.16, 95% confidence interval [CI] = 1.64–31.33, P = 0.009) and supratrochlear bump (OR = 30.5, 95% CI = 6.95–133.77, P < 0.001) as significant factors associated with jumping patella. At the final follow-up, the jumping group demonstrated significantly lower Lysholm (75.7 versus 86.1, P = 0.002) and Kujala (80.8 versus 89.9, P = 0.003) scores compared with the gliding group. The jumping group showed significantly greater patellar medial laxity index (38% versus 22%, P = 0.001), and higher rates of residual maltracking (55.6% versus 16.3%, P < 0.001), jumping patella (27.8% versus 2%, P < 0.001), MPFL graft laxity (22.2% versus 4.1%, P = 0.01), and patellar redislocation (13.9% versus 2%, P = 0.035), compared with the gliding group. The subgroup analysis revealed that in cases of MPFL reconstruction combined with tibial tubercle transfer, the jumping patella had a much higher incidence of residual patellar maltracking (54.5% versus 15.6%, P = 0.005) and positive jumping sign (27.3% versus 0%, P = 0.002), compared with the gliding group, while no significant differences were found between the two groups in patient-reported outcome measures (PROMs), MPFL graft laxity, and patellar redislocation (all P > 0.05). Conclusions Compared with the gliding patella, the jumping patella undergoing isolated MPFL reconstruction exhibited worse clinical outcomes. Although the combined procedure improved knee function and reduced redislocation rates to some extent, it could not significantly correct the persistent maltracking or jumping sign postoperatively.
Abstract Purpose The purpose of this study was to evaluate the epidemiology and longitudinal postinjury changes in playing time, competitive level, and market value in professional male football players from Spain’s First Division following anterior cruciate ligament reconstruction. Methods This retrospective cohort study included 132 anterior cruciate ligament injuries in 115 professional football players identified between the 2010–2011 and 2023–2024 seasons using public databases (Transfermarkt and BeSoccer), with cross-validation against official medical reports or news sources. Return to play, league level, minutes played, and market value were tracked up to 5 years postinjury. Statistical analyses included chi-squared tests, repeated-measures analysis of variance (ANOVA), mixed-effects models with Dunnett-adjusted comparisons, Wilcoxon signed-rank testing, and exploratory multivariate regression analyses. Results The mean age at injury was 26.7 years. The return to play rate was 97.7%, with a mean return to play time of approximately 9.1 months. The first competitive appearance occurred at a median of 13.5 days after the first matchday squad inclusion. However, 35.2% of players dropped at least one competitive league level by the first postinjury season, increasing to 61.3% by the fifth season. Minutes played decreased by 46% in the first postinjury season ( p < 0.001), with only partial recovery thereafter. Minutes per match played remained approximately 21 min below preinjury values during both the first and second postoperative seasons (both p < 0.001). Market value declined significantly across follow-up, reaching up to a 47.7% reduction by year 5, particularly among players aged 30 years or older. Conclusions Longitudinal reductions in playing time, competitive level, and market value were observed following ACL injury in professional football players, despite high return to play (RTP) rates. Reduced minutes per match played further indicated persistent limitations in competitive utilization during the first two postoperative seasons.
