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.
Whether a history of native hip or knee septic arthritis is associated with an increased risk of periprosthetic joint infection (PJI), aseptic revision, or reoperation after total joint arthroplasty (TJA) remains unclear. This meta-analysis aimed to evaluate whether patients with a history of native hip or knee septic arthritis (septic arthritis group) are at higher risk of PJI, aseptic revision, and reoperation after primary TJA than those without (nonseptic arthritis group). We hypothesized that a history of septic arthritis is associated with an increased risk of complications after TJA. A systematic literature search of MEDLINE, Embase, and the Cochrane Library was conducted to identify studies comparing the outcomes of primary TJA between patients with a history of native hip or knee septic arthritis and those without. Previous studies reporting postoperative infection, aseptic revision, or reoperation rates were included in the analysis. The septic arthritis group comprised patients with sequelae of childhood joint infection and those who underwent one- or two-stage TJA for active or previously treated septic arthritis. Random-effects meta-analyses were performed to calculate pooled risk ratios with 95
This study aimed to compare the accuracy of bone cutting, achievement of target alignment, and early clinical outcomes between ground kinematically aligned total knee arthroplasty (KA-TKA) performed using the VELYSTM robotic-assisted solution (VRAS) and that performed using an accelerometer-based portable navigation system (APNS) in patients with varus osteoarthritis. This cohort study prospectively enrolled 35 consecutive patients who underwent ground KA-TKA using the VRAS and compared them with 35 consecutive patients treated with the same surgical procedure using the APNS. The primary end point was the accuracy of bone cutting and achievement of target alignment. Clinical outcomes were evaluated at 1 year postoperatively. The VRAS group demonstrated significantly smaller mean absolute errors from target values, particularly in femoral bone cutting and achievement of a neutral ground mechanical axis, compared with the APNS group (0.7 ± 0.8° versus 1.5 ± 1.1°, 1.6 ± 1.8
Proprioceptive deficits following anterior cruciate ligament reconstruction (ACLR) are commonly assessed using sagittal-plane, nonweight-bearing tasks that may not reflect the demands of functional activities. This study evaluated the test–retest reliability and discriminative validity of a weight-bearing knee valgus discrimination task (Knee-VEDA) and compared proprioceptive acuity, muscle activity, dynamic balance, and patient-reported outcomes between individuals with ACLR and healthy controls. Sixty-three participants (32 ACLR, 31 controls) performed the Knee-VEDA with concurrent surface electromyography (sEMG) of seven lower-limb muscles. Test–retest reliability was assessed. Dynamic balance and patient-reported outcomes were evaluated using the Y-Balance Test, International Knee Documentation Committee (IKDC) form, and Knee injury and Osteoarthritis Outcome Score (KOOS). The Knee-VEDA demonstrated acceptable-to-good test–retest reliability (ACLR ICC = 0.84; controls ICC = 0.64) and acceptable discriminative validity (AUC = 0.835, p < 0.001). The ACLR group exhibited significantly poorer proprioception in the operated limb compared with their intact limb and controls (p < 0.001). sEMG analysis revealed not statistically significant between-group differences in lower-limb muscle activity. ACLR participants also demonstrated inferior Y-Balance performance compared with controls (p = 0.02). In the ACLR group, better Knee-VEDA scores correlated with better Y-Balance (r = 0.50, p < 0.001), and better KOOS symptoms scores (r = 0.55, p = 0.001). The Knee-VEDA may be a useful tool for assessing weight-bearing knee proprioception after ACLR, showing acceptable test–retest reliability and discriminative validity. After ACL reconstruction, operated-limb proprioceptive acuity was found to be reduced during the valgus task. Further validation is needed before clinical application.
Abstract Background Following anterior cruciate ligament reconstruction (ACLR), the vastus medialis (VM) commonly exhibits functional deficits largely attributed to neuromuscular alterations. This study aimed to investigate the immediate effects of terminal knee extension (TKE) exercise synchronized with auditory cues on VM motor unit behavior in individuals 2 weeks postACLR. Methods The study recruited 38 individuals who underwent primary ACLR 2 weeks postsurgery and they were randomly assigned to experimental or control groups. The experimental group performed three sets of TKE exercises synchronized with auditory cues; the control group performed identical exercises without auditory cues. Before and after the intervention, VM muscle activity, motor unit action potential (MUAP), and motor unit firing rate (MUFR) were assessed during knee extension using a Trigno–Galileo electromyography system. Within and between-group differences were analyzed using parametric or nonparametric methods, as appropriate, on the basis of data distribution. Statistical significance was set at p < 0.05. Results Data from 20 participants (10 experimental, 10 control) were included in the final analysis. The auditory-cued group demonstrated significantly greater increases in peak [12.59 (IQR 17.89) µV, p = 0.043] and average [11.31 (IQR 3.04) µV, p = 0.029] MUAP compared with the noncued group [6.26 (IQR 11.02) µV and 2.24 (IQR 9.94) µV, respectively]. Moreover, only the auditory-cued group showed significant postintervention increases in average electromyography (EMG) activity [pre: 14.23 (IQR 11.37) µV; post: 17.60 (IQR 20.94) µV; p = 0.007], average MUAP [pre: 43.07 (IQR 34.30) µV; post: 50.33 (IQR 36.12) µV; p = 0.005], peak MUAP [pre: 55.54 (IQR 50.35) µV; post: 61.69 (IQR 52.92) µV; p = 0.005], and peak MUFR (pre: 10.50 ± 4.29 pps; post: 12.66 ± 3.36 pps; p = 0.016) after the intervention. Conclusions A single session of TKE exercise synchronized with auditory cues significantly increased MUAP in the VM muscle in individuals 2 weeks post-ACLR. These findings likely reflect enhanced acute neural drive and improved VM motor unit recruitment. Auditory-cued TKE may represent a potential strategy to enhance neuromuscular control during the early postoperative phase. However, these effects reflect only immediate responses, and the persistence of these adaptations with longer-term training remains to be determined. Trial registration: NCT06662955 (25 October 2024, on ClinicalTrials.gov).
Abstract I read with great interest the recently published article by Chouhan et al. examining radiological risk factors across different patterns of patellar instability. The authors investigated trochlear dysplasia, tibial tubercle–trochlear groove (TT–TG) distance, and patellar height across single-episode, recurrent, and habitual patellar dislocation phenotypes. While this phenotype-based imaging approach addresses a clinically relevant question, several methodological and conceptual considerations may limit the robustness and clinical translatability of the reported between-group differences. The analysis was performed at the knee level despite inclusion of bilateral cases, without accounting for within-patient clustering, potentially inflating statistical significance. In addition, exclusion of patients who underwent stabilization procedures, particularly among single-episode dislocators, may introduce spectrum and selection bias, exaggerating apparent phenotype contrasts. The absence of formal inter- and intraobserver reliability assessment further constrains interpretation, especially given the known measurement variability of TT–TG distance, patellar height indices, and dysplasia grading. Reported TT–TG differences between single-episode and recurrent instability were small, with substantial overlap and without confidence intervals, reliability metrics, or threshold-based analyses, limiting clinical actionability within contemporary multifactorial decision frameworks. Inclusion of habitual patellar dislocation, often a developmental condition with distinct and entrenched structural abnormalities, within the same comparative construct as episodic instability raises concerns regarding construct validity and extrapolation of management implications. In conclusion, this work tackles an important clinical topic, and its conclusions could be further consolidated by incorporating cluster-aware analyses, clearly documenting exclusion patterns and reporting measurement reproducibility and TT–TG analyses aligned with clinically actionable thresholds within a multifactorial anatomical framework.
Anterior cruciate ligament (ACL) injuries are among the most frequent ligament injuries, with autograft reconstruction considered to be the gold standard treatment. The all-soft-tissue quadriceps tendon (ASTQT) autograft has gained popularity because of its favorable graft size, reliable biomechanical strength, and reduced donor site morbidity. However, graft strength depends on the preparation, fixation, and construct stiffness. Emerging techniques, such as suture tape augmentation, may further influence biomechanical outcomes. The aim of this study was to investigate the biomechanical properties of tape-augmented ASTQT construct compared with quadrupled semitendinosus construct (QST) for anterior cruciate ligament reconstruction (ACLR) using an established cadaveric biomechanical test protocol. A total of nine human cadaveric ASTQTs and 11 QSTs were obtained from the knees of body donors. For the ASTQTs, both ends were secured using a suture tape-integrated adjustable loop suspensory fixation device. For the QSTs, the semitendinosus tendons were quadrupled and attached to two adjustable loops and stitched using the buried-knot technique described by Lubowitz. Cyclic biomechanical testing was performed following an established protocol, and load-to-failure, mode of failure, and stiffness were reported. QSTs revealed a significantly higher load-to-failure (806.1 N versus 577.9 N, P < 0.001), initial (120.7 N/mm versus 93.3 N/mm, P < 0.001) and final (153.9 N/mm versus 117.1 N/mm, P = 0.001) dynamic stiffness and higher stiffness at failure (173.8 N/mm versus 120.1 N/mm, P < 0.001) compared with ASTQTs. All ASTQTs exhibited suture tape cut-through (cheese wiring) at the proximal fixation site as their mode of failure. Conversely, suture rupture was the predominant failure mode in the QST group. In an established cadaveric test setting, the QST construct exhibited higher load-to-failure and stiffness compared with the tape-augmented ASTQT construct. The consistent cheese-wiring failure at the proximal fixation site of the ASTQT indicates that the tape-tendon interface—not the substance itself—was the limiting structural element. These findings should be interpreted as construct-specific limitations of tape augmentation in degenerated tendon tissue, rather than as evidence of intrinsic inferiority of the quadriceps tendon graft.
Accurate alignment correction is essential in medial open-wedge high tibial osteotomy (MOWHTO). However, conventional planning based on standing radiographs may not reflect postoperative intra-articular alignment changes. While differences between standing and supine radiographs have been investigated, the role of valgus-stress whole-leg radiographs in preoperative planning remains largely unexplored. This study evaluated the predictive accuracy of standing, supine, and valgus-stress whole-leg radiographs in MOWHTO planning and determined whether integrating these modalities improves alignment prediction compared with single-modality planning. This retrospective study included 71 patients who underwent MOWHTO. Preoperative standing, supine, and valgus-stress whole-leg radiographs, along with 1-year postoperative standing radiographs, were analyzed. To minimize the influence of surgical execution error and allow the analysis to focus on planning error, the achieved wedge angle was back-calculated from postoperative bony correction and reapplied to each preoperative modality to simulate the postoperative weight-bearing line ratio (Post-WBLR). Accuracy was assessed by comparing simulated and actual Post-WBLR. Multivariable regression was performed to identify predictors of actual Post-WBLR and to compare a multimodal model with the best-performing single-modality simulation. In the postoperative valgus subgroup (n = 48), supine-based simulation showed no significant difference from actual Post-WBLR (mean difference, 0.0
Perioperative corticosteroids, particularly dexamethasone, have become a widely adopted component of multimodal pain management in total knee arthroplasty (TKA). While clinical practice guidelines strongly recommend their use, detailed guidance on optimal dosing, frequency, and safety in special populations, especially patients with diabetes mellitus, is still limited. This narrative review synthesizes the current evidence on systemic perioperative dexamethasone use in TKA, focusing on clinical questions: agent and route selection, dose optimization, dosing frequency, and safety, including considerations for patients with diabetes. A literature search of PubMed, EMBASE, and the Cochrane Library was conducted for studies published between January 2015 and April 2026. Randomized controlled trials, systematic reviews, meta-analyses, clinical practice guidelines, and observational studies addressing systemic corticosteroid use in primary TKA were included. Recent evidence supports intravenous (IV) dexamethasone as the most commonly studied and clinically practical systemic agent. A 16 mg dose provides greater early analgesic and antiemetic benefit than lower doses, and repeat dosing through postoperative day (POD) 1 is supported, with extension to POD 2 emerging but not yet definitive. Perioperative dexamethasone has not been associated with increased infection or wound complications. In patients with well-controlled diabetes, it appears safe with appropriate glycemic monitoring, although safety data are largely limited to doses of 8–10 mg. Current evidence supports IV dexamethasone as an effective component of multimodal analgesia after TKA. In the general TKA population, 16 mg appears more effective than lower doses for early postoperative pain, opioid consumption, and postoperative nausea and vomiting (PONV)-related outcomes. Repeat dosing through POD 1 is supported by available evidence, whereas extension to POD 2 remains promising but requires further validation. In patients with well-controlled diabetes, perioperative dexamethasone appears safe with appropriate glycemic monitoring, although safety data are largely limited to doses of 8–10 mg, and the safety of the 16 mg dose in this population remains insufficiently defined.
Abstract Background The purpose of this study was to identify key preoperative radiographic parameters and develop a predictive model for abnormal knee joint line obliquity (KJLO) following medial open-wedge high tibial osteotomy (MOWHTO) in patients with medial compartment knee osteoarthritis. Methods This retrospective observational cohort study included 81 patients (100 knees) treated with MOWHTO. All patients had symptomatic medial knee osteoarthritis with varus alignment and underwent preoperative and postoperative long-standing radiographs under a standardized protocol. Radiographic parameters including preoperative hip-knee angle (HKA), mechanical axis deviation, mechanical lateral distal femoral angle (mLDFA), medial proximal tibial angle (MPTA), joint line congruence angle (JLCA), and KJLO were measured. Multivariable logistic regression analysis was used to identify strong predictors of abnormal postoperative KJLO, defined as an angle > 4°. The final model was selected on the basis of backward elimination method. Model’s discrimination performance was analyzed by using sensitivity, specificity, and area under the receiver operating characteristic curve (AuROC). Model stability was demonstrated by calibration plot and Hosmer–Lemeshow goodness of fit. Bootstrapping internal validation was performed to estimate model accuracy. Results Of 81 patients (100 knees), there were 65 female and 16 male patients with an average age of 50.1 years and mean body mass index (BMI) of 27.8 kg/m 2 ; 61 knees were found post-KJLO > 4°. According to the performance of logistic regression, sensitivity, specificity, and ROC were calculated to select the best formula for postoperative KJLO prediction. The final predictive model included preoperative HKA, MPTA, and KJLO, and the planned correction angle. The model demonstrated strong performance with an AuROC of 0.876 (95% CI 0.808–0.945). Calibration plot illustrated calibration-in-the-large (CITL) of 0.00, E:O of 1.00, slope of 1.00. Following internal validation, the model remained robust with AuROC of 0.875. The model demonstrated a sensitivity of 80.30%, specificity of 87.20%, positive predictive value of 90.70%, and negative predictive value of 73.90%. Conclusions This predictive model incorporating preoperative HKA, MPTA, and KJLO, and the planned correction angle, demonstrates high internal validity and serves as a robust tool for individualized surgical planning in MOWHTO. By identifying high-risk patients preoperatively, surgeons can proactively tailor treatment strategies, such as modifying the target correction angle or opting for other surgical options. Trial registration : TCTR20251003003.
Abstract Background The optimal surgical approach for knee arthroplasty remains under debate regarding reducing systemic complications. Although unicompartmental knee arthroplasty (UKA) is generally considered less invasive than total knee arthroplasty (TKA), it remains unclear whether this advantage persists across age groups. This study aimed to compare the risk of major systemic complications between UKA and TKA across age categories using a large-scale nationwide database. Methods Patients who underwent UKA or TKA between July 2010 and March 2022 were identified from the Diagnosis Procedure Combination database in Japan. The primary outcome was a composite of postoperative in-hospital death and major systemic complications requiring additional interventions. Rates of postoperative red blood cell (RBC) transfusion were also evaluated as a secondary outcome. Stabilized inverse probability of treatment weighting (IPTW) using propensity scores was applied to compare outcomes between the groups. Results The cohort included 36,235 UKA and 322,424 TKA cases. After stabilized IPTW adjustment, the composite outcome occurred less frequently after UKA than after TKA (risk ratio [RR] 0.65; 95% confidence interval [CI] 0.50–0.85; p = 0.001). The RBC transfusion rate was also reduced in the UKA group (RR, 0.09; 95% CI 0.08–0.11; p < 0.001). In subgroup analyses stratified by age (≤ 79 and ≥ 80 years), UKA was associated with a lower incidence of the composite outcome compared with TKA in patients aged ≤ 79 years (RR 0.48; 95% CI 0.34–0.68; p < 0.001), whereas no significant difference between UKA and TKA was observed among patients aged ≥ 80 years (RR 0.92; 95% CI 0.62–1.35; p = 0.670). The rate of RBC transfusion was lower in the UKA group across age groups (for ≤ 79 years, RR 0.07; 95% CI 0.05–0.09; p < 0.001; for ≥ 80 years, RR 0.12; 95% CI 0.10–0.14; p < 0.001). Conclusions RBC transfusion rates were consistently lower following UKA across age groups. While UKA was associated with fewer major systemic complications than TKA in patients aged ≤ 79 years, no such difference was observed in patients aged ≥ 80 years. In very elderly patients, careful perioperative risk assessment remains essential when considering UKA, similar to that for TKA.
Abstract Background Single-radius total knee arthroplasty (TKA) has demonstrated favorable clinical outcomes and survivorship; however, long-term comparative data between cruciate-retaining (CR) and posterior-stabilized (PS) designs within a single-radius system remain limited, particularly in Asian populations. This study aimed to evaluate the long-term clinical and radiologic outcomes and survivorship of single-radius TKA and to compare CR and PS designs in an Asian population. Methods This retrospective study included 222 knees (152 patients) that underwent primary TKA using a single-radius prosthesis between 2006 and 2015, with a minimum follow-up of 10 years. There were 112 CR knees and 110 PS knees. Clinical outcomes were assessed using the Knee Society Score, Western Ontario and McMaster Universities Osteoarthritis Index, and Forgotten Joint Score. Radiologic outcomes were also evaluated. Kaplan–Meier survivorship analysis was performed using revision for all causes and aseptic revision as endpoints. Inverse probability of treatment weighting (IPTW) was applied to adjust for baseline differences between groups. Results At a mean follow-up of 13.2 ± 2.8 years, significant improvements were observed in all clinical outcomes compared with preoperative values (all p < 0.001). At the final follow-up, clinical outcomes did not differ significantly between the CR and PS groups, and IPTW-adjusted analyses also showed no statistically significant between-group differences. Revision surgery was performed in 6 of 222 knees (2.7%), with no difference between groups ( p = 0.44). In the overall cohort, the 15-year Kaplan–Meier survivorship free from revision for all causes was 96.2% (95% CI 93.2–99.4). The estimated 15-year aseptic revision-free survivorship was 98.9% (95% CI 96.9–100) in the CR group and 95.6% (95% CI 91.4–100) in the PS group. Survivorship did not differ significantly between the CR and PS groups for either all-cause or aseptic revision (log-rank p = 0.99 and p = 0.99, respectively). However, only six revision events occurred, limiting the statistical power to exclude a clinically meaningful between-group difference. Conclusions Single-radius TKA demonstrated favorable long-term clinical outcomes and high survivorship in an Asian population. No significant between-group differences were identified in clinical outcomes or survivorship between the CR and PS groups.
Anterior cruciate ligament reconstruction (ACLR) is among the most frequently performed and successful procedures in orthopedic surgery. Nevertheless, a substantial proportion of patients experience postoperative “failure,” a term that remains inconsistently defined throughout the literature. This narrative review critically analyzes the heterogeneity of definitions applied to ACLR failure, underscoring persistent gaps, contradictions, and their implications for clinical practice and research. We subsequently propose an integrative definition that aligns with both the clinical and functional objectives of reconstruction. Failure may result from multiple factors, including but not limited to technical, biological, traumatic, and patient-related, and inconsistencies arise when definitions rely exclusively on graft rupture, revision surgery, laxity thresholds, or isolated patient-reported symptoms. Although current consensus statements acknowledge this variability, they fail to provide operational definitions. Consequently, reported failure rates vary considerably, limiting comparability across studies. We advocate defining ACLR failure, as the presence of any of the following: objective or subjective post-operative instability, persistent knee pain, functional limitation including restricted range of motion, documented graft rupture, or new symptomatic meniscal injury in the absence of significant trauma. This multidimensional, patient-centered framework reflects the fundamental goals of ACLR and may serve as a foundation for standardized reporting criteria in future clinical and research endeavors.
Limb length discrepancy (LLD) following total knee arthroplasty (TKA) may affect functional outcomes and patient satisfaction. However, relative impact of coronal and sagittal plane deformity correction on change in limb length (CLL) following TKA are still not fully understood. The aim of this study is to guide the surgeon regarding the expected change in limb lengths following correction of coronal and sagittal plane deformities. This retrospective study comprised 237 primary TKAs conducted by a single surgeon from August 2024 to July 2025. Preoperative deformities consisted of 215 varus and 22 valgus knees. Standing anteroposterior radiographs of full length were used to assess the hip–knee–ankle (HKA) angle and limb length before and after the operation. Flexion contracture was assessed through clinical measurement. Correlation and multivariable regression analyses were conducted to ascertain predictors of limb length alteration, while adjusting for possible confounders such as patient height and polyethylene insert thickness. A regression-based predictive model was subsequently developed. Mean limb length showed a notable increase after TKA (10.4 ± 9.1 mm; p < 0.0001). The preoperative HKA angle showed a significant positive correlation with CLL in both varus and valgus knees and remained the strongest independent predictor (p < 0.001 for varus; p = 0.046 for valgus). Preoperative flexion contracture did not show a significant independent association with CLL. Patient height and the thickness of the polyethylene insert did not have a notable effect on changes in limb length. TKA leads to consistent limb lengthening, mainly caused by the correction of coronal plane deformities. Estimating limb length changes before surgery can aid in surgical planning and patient counseling, especially in cases of unilateral or staged bilateral TKA. Level of evidence III, Retrospective comparative cohort study
Abstract Background Research has investigated the function of biomarkers, such as the platelet–lymphocyte ratio (PLR), in identifying periprosthetic joint infection (PJI) after total hip arthroplasty (THA) and total knee arthroplasty (TKA). This study aimed to conduct an updated systematic review and meta-analysis in order to assess the diagnostic efficacy of PLR for PJI. Methods Reviews of databases including PubMed, Scopus, and Web of Science were conducted to identify studies related to the use of PLR in diagnosing PJI. The evaluations covered the diagnostic performance of PLR for PJI. Furthermore, because of the significant heterogeneity across the studies, subgroup analyses were conducted focusing on geographic region (China versus other countries), site surgery (unseparated hip and knee versus separated hip and knee), and patient numbers (more than 200 versus less than 200). Results A total of 4892 TKA and THA patients from 17 studies were included in the meta-analysis. Of the total patients, 1980 (40.5%) were diagnosed with PJI. Diagnostic sensitivity and specificity combined were 0.70 (95% CI 0.62–0.77) and 0.73 (95% CI 0.65–0.79), respectively. Results from the subgroup analysis indicated enhanced sensitivity and specificity concerning geographic differences, surgical site variances, and studies with fewer than 200 patients. Conclusions PLR demonstrated moderate diagnostic accuracy and could function as an accessible supplementary marker in the evaluation process of PJI; additional research is necessary to establish optimal thresholds and its benefit alongside current diagnostic standards.
Tibial fixation is the biomechanical weak point in anterior cruciate ligament (ACL) reconstruction, with numerous techniques proposed to address this challenge. This study evaluates the utility of a simple, cost-effective system: high-strength suture tying over a bone bridge (BB). Its effectiveness as standalone fixation and as a supplement to standard interference screw (IS) fixation is compared with IS alone and supplemented with other commercial systems. A biomechanical study was conducted using six fixation methods tested on 61 specimens with bovine extensor tendons in porcine tibial models. Groups included BB alone, IS alone, and four hybrid fixation methods: IS + BB, IS + a cortical screw post (CSP), IS + a PushLock® anchor, and IS + a SwiveLock® anchor, with at least nine specimens per group. Specimens underwent cyclic load testing (500 cycles at 100–200 N) and pull-to-failure tests (20 mm/min) to measure displacement, ultimate load to failure, and stiffness. Standalone BB fixation showed limited performance, with an ultimate load to failure of 357.81 ± 90.53 N and cyclic displacement of 14.88 ± 3.28 mm, insufficient for early rehabilitation. When combined with IS, BB significantly improved performance, achieving an ultimate load to failure of 500.55 ± 151.24 N, comparable to commercial systems, and reducing cyclic displacement to 4.82 ± 0.83 mm. Hybrid fixation methods lowered early failure rates to 10
Abstract Background Preoperative rehabilitation is one of the strategies for enhanced recovery after surgery (ERAS) following total knee arthroplasty (TKA), but the optimal duration remains inconclusive. This study aims to evaluate the impact of a 4-week home-based prehabilitation program on accelerating postoperative recovery in patients undergoing TKA. Methods In this retrospective cohort analysis, 176 patients undergoing primary unilateral TKA were categorized into two groups: those who completed a 4-week home-based prehabilitation program (training group, n = 72) and those who did not (control group, n = 104). Baseline demographics, perioperative data, pain scores, and functional outcomes were collected. Patients were followed for over 1 year. The primary outcome was the Western Ontario and McMaster Universities Arthritis Index (WOMAC), and secondary outcomes included visual analog scale (VAS), knee range of motion (ROM), Knee Society Score (KSS), timed up-and-go (TUG) test, and stair climbing test. Assessments were performed at baseline, before surgery, and multiple time points after TKA. Results Baseline characteristics were comparable between groups. The training group demonstrated significantly earlier first postoperative ambulation (median 9 versus 12 h, P = 0.003) and shorter hospital stays (median 7 versus 10 days, P = 0.002). Pain scores (VAS) were significantly lower in the training group at 1 day and 1 week postoperatively (P < 0.05). Functional outcomes including ROM, KSS, TUG, and stair test were superior in the training group at 1 and 3 months (P < 0.05). WOMAC total scores and its subscales (pain, stiffness, function) also showed significant improvements in the Training group at 1 and 3 months (P < 0.05). While advantages in ROM and TUG persisted up to 6 months, no significant between-group differences were observed at 12 months for any outcome measure. Conclusions A 4-week home-based prehabilitation program significantly enhances early recovery after TKA, as evidenced by reduced hospital stay, lower early postoperative pain, and improved functional outcomes within the first 3 months. Although benefits in certain functional measures persist up to 6 months, outcomes converge by 12 months. These findings support the integration of structured 4-week home-based prehabilitation program into ERAS pathways.
Abstract Background Postoperative pain management is crucial for optimising recovery after total knee arthroplasty. Adequate pain control facilitates early rehabilitation, enhances quadriceps muscle recovery, improves knee function and improves patient satisfaction. Corticosteroids are widely used for postoperative pain management. However, studies comparing the efficacy of periarticular (PA) and intravenous (IV) corticosteroid injection are limited. Therefore, this study aimed to evaluate the effect of PA and IV corticosteroid injections on quadriceps strength (QS) recovery in patients undergoing total knee arthroplasty. Methods A total of 59 patients were included in this study. Patients were randomly assigned to two groups: the PA triamcinolone group (n = 29) and the IV hydrocortisone group (n = 30). Patients were followed up for 6 months and their QS, Visual Analogue Scale score, Modified Timed Up and Go (MTUGT) score, Western Ontario and McMaster Universities Osteoarthritis Index score, Knee Society Score and inflammatory marker levels were assessed. Results On postoperative day 3, the PA group exhibited a significantly lower reduction in QS (−43.11% ± 23.36% versus −63.7% ± 17.67%, p = 0.02) and significantly lower changes in MTUGT scores than the IV group (153.3% versus 301.3%, p < 0.01). Additionally, the knee flexion angle was significantly greater in the PA group than in the IV group on postoperative day 3 (91° ± 11° versus 82.6° ± 10.9°, p < 0.01) and at week 2 (103.2° ± 12.2° versus 97.4° ± 8.7°, p = 0.04). C-reactive protein levels were significantly lower in the PA group than in the IV group on postoperative day 1 (10.4; IQR: 5.3–17.2 versus 15.4; IQR: 9.4–28.6, p = 0.01), on day 3 (65.5; IQR: 38.3–96 versus 119.1; IQR: 69.6–146.1, p < 0.01) and at week 2 (3.9 versus 8.9, p = 0.01). On postoperative day 3, the PA group had significantly higher glucose levels than the IV group (115; IQR: 106–127 versus 106; IQR: 93–122, p = 0.02). No wound complications were observed in both groups. Conclusions PA corticosteroid injection improves knee function in terms of muscle recovery, faster ambulation, increased knee flexion and reduced inflammation for up to 2 weeks after surgery compared with IV corticosteroid injection. A transient increase in serum glucose was observed but is unlikely to be clinically significant.
