Journal of Experimental Orthopaedics最新文献

The integration of artificial intelligence (AI), the rise of mega-journals, and the manipulation of impact factors present challenges to scientific integrity. These trends threaten the core principles of objectivity, reproducibility, and transparency. This editorial highlights two categories of threats: (1) external pressures, such as AI misuse and metric-driven publishing models, and (2) internal systemic flaws, including the ‘publish or perish’ culture and methodological fragility. Mega-journals, characterized by high-volume publishing and broad interdisciplinary scopes, improve accessibility and accelerate dissemination. However, the emphasis on publication volume might weaken the rigor of peer review. To navigate these challenges, the authors propose a balanced approach that harnesses innovation without compromising scientific integrity. Proposed solutions include mandating AI transparency through frameworks like CONSORT-AI, and redefining impact metrics to emphasize reproducibility, mentorship, and societal impact alongside citations. Scientific journals should promote career opportunities less on publication quantity and more on quality. Global cooperation, via initiatives like the San Francisco Declaration on Research Assessment (DORA) and the Committee on Publication Ethics (COPE), is essential to standardize ethics and address resource disparities. This editorial proposes solutions for researchers, journals, and policymakers to realign academic incentives and uphold the ethical foundation of the science. By fostering transparency, accountability, and equity, the scientific community can preserve its ethical foundations while embracing transformative tools—ultimately advancing knowledge and serving society.

Level of Evidence

Level V.

Purpose

Anterior cruciate ligament (ACL) injuries have consistently been linked to specific kinetic and kinematic patterns, including elevated vertical ground reaction forces, increased knee abduction angle and moment (dynamic valgus), reduced knee flexion during landing and excessive hip adduction/internal rotation. However, the relationship between motor competence as a factor affecting athletes' performance and kinetic and kinematic variables has not yet been investigated.

Methods

A total of 112 elite athletes (66 males and 46 females; mean age = 19.4 ± 1.1 years) from basketball, volleyball and handball were assessed. Motor competence was evaluated using the short form of the Bruininks–Oseretsky Test of Motor Proficiency. Biomechanical data were collected during a single-leg drop landing task using a three-dimensional motion analysis system (Vicon) and a force plate. Pearson correlation coefficients and multiple linear regression (Enter method) were used to analyse relationships between motor competence and kinetic/kinematic variables.

Results

All biomechanical variables showed significant correlations with motor competence (p < 0.001). Notably, knee flexion angle (r = 0.613) and knee abduction angle (r = −0.576) demonstrated strong associations. Regression analysis identified several biomechanical variables that were statistically associated with motor competence, explaining 69.6% of its variance.

Conclusion

Motor competence was related to several kinetic and kinematic variables previously linked to ACL injury risk. However, due to the cross-sectional design, these associations should not be interpreted as causal, and further longitudinal or interventional studies are warranted.

Level of Evidence

Level IV, cross-sectional study.

Purpose

To explore the results of a fluoroscopic-guided intra-osseous (IO) and intra-articular (IA) injection of expanded adipose-derived stromal cells (ASCs) in athletes with bone marrow lesions (BML) associated with knee osteoarthritis (OA).

Methods

A prospective study was conducted on 16 athletes (9 males, 7 females; mean age 30.5 ± 2.8 years), including two with bilateral knee involvement. All had Kellgren-Lawrence grades 2–4 and received IA and IO injections of 24.3 ± 2.1 million and 23.4 ± 1.9 million ASCs, respectively. Clinical outcomes were assessed using the Knee Injury and Osteoarthritis Outcome Score (KOOS), Numeric Pain Rating Scale (NPRS), and Tegner activity scale at baseline, 6 months, and 12 months. Radiological changes were evaluated using Magnetic Resonance Imaging Osteoarthritis Knee Scores (MOAKS) at baseline and 12 months.

Results

Significant improvements were observed in NPRS, Tegner, and all KOOS subscales at 6 months and 12 months with respect to baseline (p < 0.05). At 12 months, NPRS decreased from 6.6 ± 0.9 to 2.4 ± 0.5, and Tegner increased from 4.4 ± 1.8 to 7.8 ± 1.1. All KOOS subscale scores improved at 12 months. Symptoms: 49.3 ± 6.4 to 74.1 ± 4.9; pain: 49.4 ± 4.3 to 75.8 ± 3.2; sport and recreation: 30.6 ± 6.2 to 67.8 ± 4.3; activities of daily living: 57.6 ± 3.6 to 79.9 ± 4.8; and quality of life: 35.4 ± 10.3 to 66.3 ± 5.3. A mild decline yet significant in the KOOS sport and recreation subscale was noted between 6 and 12 months (p = 0.02), but remained significantly improved from baseline. MOAKS analysis showed improvement in 12 of 27 evaluated regions. No major complications occurred.

Conclusions

Combined IA and IO ASC injections are a safe and effective treatment for OA-BMLs in athletes, offering sustained clinical and radiological benefits over 12 months.

Level of Evidence

Level III.

Purpose

To evaluate whether a high lateral distal femoral angle (LDFA) contributes to undercorrection of lower-limb alignment following medial open wedge high tibial osteotomy (MOWHTO), and to determine the LDFA threshold above which tibial correction alone may be insufficient.

Methods

This retrospective study analysed 68 patients who underwent MOWHTO at our hospital between 2020 and 2022. Based on their postoperative mechanical axis (MA), patients were categorised into two groups: the acceptable correction group (A-group; MA 57%–67%) and the undercorrection group (U-group; MA ≤ 56%). Radiographic parameters before and after surgery were compared between the two groups. Simple and multiple regression analyses were used to identify factors affecting postoperative MA. A receiver operating characteristic (ROC) curve was utilised to identify the LDFA cut-off value associated with undercorrection.

Results

A total of 54 patients met the inclusion criteria (A-group, n = 35; U-group, n = 19). The U-group demonstrated a significantly higher preoperative mechanical LDFA (89.5° vs. 87.6°, p = 0.001) and a lower medial proximal tibial angle (mMPTA) (84° vs. 86°, p = 0.014) than that in the A-group. Both mLDFA (p = 0.006) and mMPTA (p = 0.010) were independent predictors of postoperative MA in multiple regression analysis. The ROC analysis identified an LDFA cut-off of 89.2° for predicting undercorrection (area under the curve = 0.78; sensitivity, 36.8%; specificity, 88.6%). Patients with an LDFA ≥ 89.2° had significantly higher body mass index, joint line convergence angle, varus stress angle, percentage condylar tibial translation and preoperative knee joint line obliquity.

Conclusions

A high LDFA (≥89.2°) is associated with an increased risk of undercorrection after MOWHTO, despite accurate tibial correction. These findings suggest that in cases with significant distal femoral varus, isolated tibial osteotomy may be insufficient. Double-level osteotomy, including femoral correction, should be considered in such cases to achieve optimal alignment.

Level of Evidence

Level Ⅳ, retrospective comparative study.

Purpose

The primary aim was to study the impact of joint line obliquity (JLO) on clinical outcomes and survivorship in patients undergoing total knee arthroplasty (TKA) after a previous high tibial osteotomy (HTO). The secondary aim was to study how maintaining neutral JLO at both HTO and TKA affected clinical outcomes of TKA.

Methods

A retrospective review of patients undergoing TKA following valgus-producing HTO, having a minimum 1-year follow-up, was performed. Using the coronal plane alignment of the knee (CPAK) classification, three groups of JLO were formed: distal JLO (<177°), neutral JLO (177–183°) and proximal JLO (>183°). Clinical outcomes were assessed using the Western Ontario and McMaster University Osteoarthritis Index (WOMAC). The level of significance was 0.05.

Results

The study included 110 TKA (mean follow-up: 5.8 years). Prevalence of a proximal JLO post-TKA was higher (p < 0.05) in those with a proximal JLO pre-TKA (40%) as compared to those with a neutral JLO pre-TKA (13%). The odds ratio of having a proximal JLO post-TKA was 4 (95% confidence interval: 1.4–11.1, p < 0.05) in those having a proximal JLO pre-TKA. Revision rate in the proximal JLO post-TKA, neutral JLO post-TKA and distal JLO post-TKA groups was 20%, 8% and 4% respectively, with no statistical difference (p > 0.05). Post-TKA, the stiffness, function and total WOMAC were significantly better (p < 0.05) in patients with a neutral JLO pre-TKA and neutral JLO post-TKA as compared to those with a proximal JLO pre-TKA and proximal JLO post-TKA or a proximal JLO pre-TKA and neutral JLO post-TKA.

Conclusion

While a proximal JLO after conversion TKA did not show a statistically higher revision rate, maintaining a neutral JLO during HTO and at the time of subsequent TKA was associated with higher post-operative clinical scores. However, further research in different and larger populations is needed to confirm these findings.

Level of Evidence

Level IV.

Purpose

To assess the mid- to long-term clinical and functional outcomes and return to sports following derotational distal femoral osteotomy (DDFO) for the treatment of recurrent patellofemoral instability and associated increased femoral antetorsion.

Methods

Patients who underwent DDFO as well as concomitant procedures between 2007 and 2016 were eligible for inclusion. Recurrent instability, complications, revision surgery and return to sports rates were evaluated after a minimum follow-up of 5 years. Kaplan–Meier survival analysis was performed for the risk of recurrent instability or undergoing further surgery other than hardware removal. Patient-reported outcome measures (PROMs; Visual Analog Scale [VAS] for pain, Tegner Activity Scale [TAS], Kujala score, Banff Patellofemoral Instability Instrument [BPII] 2.0 and Patellofemoral Instability-Return to Sport after Injury [PFI-RSI] scale) were recorded.

Results

Of 44 knees in 42 patients eligible for inclusion, 25 knees in 24 patients (64% female) with a mean age of 27.3 ± 9.0 years at the time of surgery were available for follow-up at a mean of 8.7 ± 2.7 years (follow-up: 57%). Two patients (5%) underwent early revision surgery due to loss of osteosynthesis at the distal femur. Three patients (12%) reported subjective recurrent instability at a median of 3.9 (3.5–7.0) years post-operatively. The Kaplan–Meier estimator showed a survival probability free of recurrent instability and revision (except hardware removal) of 87% (95%-confidence interval 76%–100%) at 5 years. At final follow-up, patients reported good knee function (Kujala score: 78.5 ± 16.6), knee-related quality of life (BPII: 68.3 ± 22.3), psychological readiness to return to sport (PFI-RSI: 73.3 [43.8–90.0]), and moderate activity levels (TAS: 4.0 [3.0–4.0]). The majority of patients returned to sports (84%).

Conclusion

DDFO provided effective treatment for recurrent patellofemoral instability associated with increased femoral antetorsion. Favourable clinical and functional outcomes as well as high return to sport rates were observed at a mid- to long-term follow-up.

Level of Evidence

Level IV, retrospective case series.

Purpose

Robotic-assisted total knee arthroplasty (TKA) has emerged as a reliable strategy to improve surgical accuracy and enable functional alignment (FA), also referred to as functional knee positioning (FKP). However, its application in patients with major coronal plane deformities remains under-investigated. This study aimed to evaluate complication rates, implant survival, radiographic outcomes and patient-reported measures in patients with severe deformities undergoing robotic-assisted TKA with FA/FKP principles compared to matched controls.

Methods

A retrospective comparative study was conducted on patients who underwent robotic-assisted TKA between March 2021 and February 2023 at a single high-volume centre. Patients with ≥15° varus or ≥10° valgus deformity were included in the study group and matched 1:1 with controls presenting neutral alignment. All procedures used the Mako robotic-arm-assisted system with standardised FA/FKP principles. Clinical outcomes included knee society score (KSS), forgotten joint score (FJS-12), Kujala anterior knee pain scale (AKPS) and range of motion. Radiographic measurements and robotic data were assessed. Complications, reoperations and revision rates were analysed.

Results

Eighty-eight patients (44 per group) were analysed, with a mean follow-up of 2.8 ± 0.9 years. Complication and revision rates were comparable between groups (revision: 2.3% vs. 0%, p = 0.987). Patients with major deformities achieved higher FJS-12 scores (83.9 ± 20.2 vs. 74.9 ± 19.0, p = 0.040), although the difference did not exceed the minimal clinically important difference (MCID = 9.9). Postoperative mHKA was less neutral in the deformity group (176.8° ± 4.7 vs. 180.0° ± 3.0, p = 0.002), without adverse impact on implant survival.

Conclusions

Robotic-assisted TKA performed with FA/FKP principles appears to be a feasible option for patients with severe varus or valgus deformities. Despite residual alignment variability, complication and revision rates remained comparable to standard cases, and patient-reported outcomes suggested greater perceived functional improvement.

Level of Evidence

Level III.

Purpose

This study introduces the posterior tibial plateau offset (PTO). It was hypothesised that (1) the PTO is reliably quantifiable and (2) correlates with the posterior tibial slope (PTS).

Methods

The study involved lateral radiographs of patients who sustained an anterior cruciate ligament (ACL) graft failure and a control group. Exclusion criteria were skeletal immaturity, osteoarthritis (Kellgren and Lawrence grade > I), lateral radiographs with <15 cm of tibial shaft, or malrotated radiographs. The PTS was measured in both groups. The PTO was defined as the relative distance from the posterior tibial plateau to the tibial shaft axis in relation to the sagittal diameter of the tibial plateau (in%). Linear correlation assessed the PTS to PTO association.

Results

A total of 146 patients (ACL graft failure, n = 103; control group, n = 43; 45% female, 60% left knees) were included. Mean overall PTO was 82% ± 7% (1%–35%), and mean PTS was 12° ± 3 (7–20). The PTS and PTO showed a moderate positive correlation in the overall collective (r = 0.5; p < 0.001), ACL graft failure group (r = 0.49; p < 0.001), and control group (r = 0.69; p < 0.001), indicating a higher slope corresponded to a greater PTO. There was no statistical difference in PTO between the ACL failure and the control group (82% vs. 83%, p < 0.05). ICC between three raters was (0.8–0.9; p < 0.05).

Conclusion

The PTO is a simple and repeatable measurement. A higher PTS is associated with a greater PTO, and the variability of the PTO across the patients with ACL graft failure and the control group was high. When planning osteotomy levels in the highly sloped proximal tibia, the PTO may be considered to optimise individualised planning for patients with failed ACL reconstruction.

Level of Evidence

Level V.

Purpose

Unicompartmental knee arthroplasty (UKA) is a widely used treatment for isolated compartmental knee osteoarthritis, especially in younger and more active patients. Return to sport (RTS) has become a key postoperative outcome. While RTS after UKA is generally favourable, the influence of factors such as implant design, surgical technique, compartment treated and patient characteristics remains unclear. An updated and granular synthesis is needed, particularly to allow direct comparison with RTS outcomes after total knee arthroplasty (TKA).

Methods

A systematic review and meta-analysis was conducted following PRISMA guidelines and registered on PROSPERO. PubMed, Embase and Scopus were searched for studies from 2016 to April 2025 reporting RTS outcomes after UKA. Two reviewers independently screened articles, extracted data and assessed methodological quality using the modified Coleman Methodology Score. Weighted means and proportions were calculated, and correlation analyses explored associations between RTS and patient and surgical variables.

Results

Thirteen studies (n = 1675 patients) were included. The overall weighted mean RTS rate after UKA was 87.97% with a substantial proportion of patients resuming intermediate and high-impact sports. No significant differences in RTS were found between fixed-bearing and mobile-bearing implants, or between medial and lateral UKA. RTS was comparable between robotic-assisted and standard techniques. A moderate negative correlation between BMI and RTS was observed (r = −0.69, p = 0.019). Compared to TKA, UKA patients have a higher RTS rate (87.97% vs. 72%). UKA patients resumed a broader range of sports, with increased participation in intermediate- and high-impact activities.

Conclusions

UKA offers high RTS rates and supports participation in demanding physical activities. Neither implant design nor surgical technique substantially impacts RTS, whereas patient-related factors, especially BMI, are key predictors. Compared to TKA, UKA is associated with superior sport-related outcomes, underscoring its role in appropriately selected patients. These findings support shared decision-making and personalised postoperative planning.

Level of Evidence

Level III.