Knee Surgery and Related Research最新文献

Aim: To investigate the variants of lateral hinge fracture and its outcome, as well as to develop a MRI based classification on the fracture line pattern.

Methods: This retrospective study analyzed 250 knees from 227 patients (169 females, 58 males) who underwent medial opening wedge high tibial osteotomy. Lateral hinge fractures were detected using MRI and classified into four types on the basis of the fracture line pattern: type A (proximal to the tibiofibular joint), type B (into the proximal tibiofibular joint), type C (distal to the tibiofibular joint), and type D (proximal into the joint). Patients were followed up with radiographs and computed tomography (CT) scans to monitor outcome.

Results: Type A fractures had a shorter union time (3.66 months) than type B (5.17 months), type C (6.24 months), and type D (5.75 months). Type B had a delayed union rate of 20%, higher than that of type A (2.46%). Statistical analysis confirmed that type A fractures had significantly better outcomes than types B, C, and D. Type B fractures are by definition Takeuchi type I fractures but exhibit clinical characteristics similar to type II fractures, including longer union times and a higher risk of delayed union.

Conclusions: Type A fracture has union rates similar to those in non-fracture groups, whereas type B fracture has clinical similarities to Takeuchi type II fractures and therefore should be considered and managed as a subtype of Takeuchi type II fractures.

Background: Isolated medial patellofemoral ligament (MPFL) reconstruction is an effective, low-morbidity treatment for recurrent lateral patellofemoral instability (RLPI). The presence of major anatomical risk factors continues to generate controversy in surgical decision-making. It remains unclear whether the coexistence of multiple risk factors requires associated bony procedures or whether isolated MPFL reconstruction alone is sufficient. The purpose of this prospective study was to compare clinical outcomes, recurrence rates, return to sport, and patellofemoral degenerative changes in athletes with RLPI presenting with ≤ 1 versus 1 associated major risk factor treated with isolated MPFL reconstruction.

Methods: This prospective cohort study included athletes aged 16-30 years with RLPI who underwent isolated MPFL reconstruction between 2013 and 2020. Patients were stratified according to the number of associated major risk factors (MRFs): ≤ 1 MRF (group 1) and 1 MRF (group 2). MRFs included trochlear dysplasia, patella alta, increased tibial tuberosity-trochlear groove distance, increased femoral anteversion, and increased tibial torsion. All patients underwent isolated MPFL reconstruction using the same surgical technique. Functional outcomes were assessed using the Knee injury and Osteoarthritis Outcome Score (KOOS), Kujala score, International Knee Documentation Committee (IKDC) score, and Lysholm score. Recurrence of instability, return to sport (RTS), and patellofemoral degenerative changes were evaluated. Minimum follow-up was 5 years.

Results: A total of 86 athletes (43 per group) completed a minimum 5-year follow-up. Both groups showed significant postoperative improvements in all functional scores. At final follow-up, no between-group differences were observed (KOOS QoL mean difference 2.1; Kujala 0.8; IKDC 1.2; Lysholm 1.5; all p 0.05). MCID and PASS achievement rates were comparable between groups. Recurrence occurred in one patient per group (2.3%). More than 90% of athletes returned to sport at their preinjury level within 1 year. Mild, asymptomatic patellofemoral degenerative changes were observed in a small proportion of patients, with no between-group differences.

Conclusions: With a medium-term follow-up, isolated MPFL reconstruction appeared to be a reliable and effective surgical option for treating RLPI in athletes from both groups. The procedure was associated with significant improvements in both primary and secondary outcomes and remained effective regardless of the number or type of associated major risk factors.

Level of evidence: II, prospective cohort study.

Purpose: We aimed to compare the anterior and posterior approach for transtibial pull-out repair of medial meniscal posterior root tear (MMPRT) in terms of tibial tunnel positioning of the posterior horn, healing status, medial meniscal extrusion (MME), medial joint space (MJS) narrowing, and clinical outcomes.

Methods: This retrospective study included patients who underwent arthroscopic transtibial pull-out repair for MMPRT between May 2019 and June 2023. Tibial tunnel positioning was assessed postoperatively using computed tomography. The healing status was evaluated using magnetic resonance imaging (MRI) at the 1-year follow-up visit. Pre- and postoperative MME and MJS widths were measured using MRI and weight-bearing radiography, respectively. Clinical outcomes were assessed preoperatively and at the 2-year follow-up using the International Knee Documentation Committee subjective score, Lysholm score, Knee Injury and Osteoarthritis Outcome Score, and Tegner activity scale.

Results: A total of 77 patients were initially evaluated for eligibility, of whom 23 were excluded. A total of 54 patients were analyzed (26 anterior approach (AA), 28 posterior approach (PA)). The PA group demonstrated significantly more accurate tibial tunnel positioning compared with the AA group (mean absolute distance: 2.8 ± 2.0 mm versus 4.9 ± 3.2 mm, p = 0.001). MRI at follow-up demonstrated that complete or partial healing was achieved in 88.9% of cases, with no significant difference between groups (p = 0.413). Overall, MME increased from 3.0 ± 0.9 mm to 4.0 ± 1.6 mm (p = 0.022) and MJS decreased from 3.5 ± 1.2 mm to 3.1 ± 1.3 mm (p = 0.001), without intergroup differences. All clinical scores improved significantly from baseline, but no significant differences were observed between approaches at final follow-up.

Conclusion: The PA group achieved more accurate replication of the posterior horn insertion than the AA group; however, no definitive advantages were observed in short-term clinical or radiographic outcomes.

Level of evidence: III, retrospective comparative cohort study.

Background: Robotic-assisted unicompartmental knee arthroplasty (R-UKA) is an emerging procedure; however, its benefits over conventional manual unicompartmental knee arthroplasty (C-UKA) are controversial, especially the revision and failure rates, and existing studies failed to reach a consensus on this issue.

Methods: The literature search was conducted on four databases (PubMed, Embase, Cochrane Library and Web of Science) from inception to 28 April 2025 according to the guidelines for Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). Eligibility criteria were studies that were written in English and reported any causes for a revision or failure subsequent to UKA with comparisons between R-UKA and C-UKA. The quality of each article was assessed using the Cochrane collaboration risk of bias tool or the Newcastle-Ottawa Scale.

Results: A total of 15 studies incorporating 29,982 patients with 30,099 knees (22,290 in the C-UKA group and 7809 in the R-UKA group) were analyzed. Compared with R-UKA, C-UKA showed higher total revision rates (RR: 1.58; 95% CI: ~1.33-1.87; P < 0.00001; I² = 43%). Prosthesis loosening, infection, pain, and progression of disease were the main reasons for R-UKA revision, whereas for C-UKA revision, loosening, progression of disease, infection, and limb malalignment were the major causes. Loosening was the predominant reason in both groups across all follow-up periods; early revisions were also due to infection and disease progression. Within 2-5 years, the secondary reasons differed, being limb malalignment for C-UKA and pain for R-UKA.

Conclusions: Compared with C-UKA, R-UKA may lower the risk of revision related to loosening, disease progression, and limb malalignment. Loosening remains the primary revision cause for both. Large-scale prospective trials with unified technical details are warranted to draw more rigorous conclusions in the future.

Trial registration: PROSPERO CRD420251042604.

Purpose: Patellofemoral (PF) complications are a common cause of dissatisfaction and revision following total knee arthroplasty (TKA), often linked to altered kinematics and implant design. "Patella-friendly" femoral components with a wider, funnel-shaped trochlear groove may better restore native patellar motion. This study evaluated PF kinematics both before and after TKA performed using kinematic alignment, investigating the role of implant design and quadriceps loading.

Methods: In total, 12 paired fresh-frozen cadaveric lower limbs were tested before and after TKA. Within each pair, one limb received a traditional medial pivot femoral component, while the contralateral limb received a "patella-friendly" medial pivot femoral component. Native and implanted knees were tested by flexing the knee under the action of an external load applied through the quadriceps tendon, varying its magnitudes (20, 160, 280N) and directions in the frontal (neutral,±6°, ±12°) and sagittal plane (neutral, +5° anterior). Motion was captured using an eight-camera optoelectronic system.

Results: In the reference condition (20N, neutral direction), neither design showed statistical differences versus native (p > 0.05). However, the patella excursion in varus-valgus rotation was much higher in the specimens implanted with the traditional femoral component design (35.1° versus 14.6° native) than with the patella-friendly (20.5°). Differences between the designs emerged mainly with quadriceps load variations, especially frontal direction changes, which significantly affected patellar motion in both native and implanted knees (p < 0.05). Overall, the patella-friendly design better reproduced native kinematics under most conditions. However, with extreme medial loading (12°), three out of six specimens implanted with the patella-friendly femoral component were untestable owing to instability, and others exhibited high lateral displacement and trochlear dysplasia. In contrast, all traditional design implants remained stable, though with greater deviation from native kinematics.

Conclusions: This study provides foundational insights into PF biomechanics before and after TKA with kinematic alignment. By analyzing the interplay between implant geometry and quadriceps loading direction, it emphasizes the importance of selecting femoral components on the basis of individual patient anatomy. Our findings suggest that patella-friendly femoral components-although capable of better reproducing native motion in some cases-may not be suitable for patients with medially directed quadriceps forces or severely varus morphotypes.

Background: Shared decision-making is a collaborative approach that enables clinicians and patients to make informed treatment decisions that align with patient preferences. This study examined current practices of shared decision-making in managing knee osteoarthritis.

Methods: A comprehensive search was conducted in Cochrane, CINAHL, ProQuest, Scopus, Ovid MEDLINE, and Web of Science databases through August 2025. EndNote 21 was utilized for de-duplication, and Rayyan was used for screening. Studies were analyzed for the use of patient decision aids, shared decision-making outcome measures, and barriers and factors impacting shared decision-making practices.

Results: Of 4708 records screened, 69 studies were included for analysis, comprising 23 randomized controlled trials, 18 qualitative studies, 9 trial protocols, and 19 other observational designs. A total of 44 studies explicitly described the use of a patient decision aid. Reported outcome domains included decision quality, decisional conflict, satisfaction, regret, and patient-clinician communication. Commonly cited barriers to shared decision-making (SDM) implementation were limited clinician time, lack of awareness of patient decision aids (PDAs), and patient difficulty using digital tools.

Conclusions: The included studies suggest that patient decision aids may be a valuable tool for management of knee osteoarthritis, with studies reporting improvements in patient engagement and informed decision-making. However, variability in shared decision-making implementation and inconsistency in outcome measures highlight the need for further research to evaluate the comparative effectiveness of decision aids in clinical practice.

Background: Robotic-assisted total knee arthroplasty (RA-TKA) aims to improve surgical accuracy and reduce soft-tissue trauma. The bone-milling technique may further decrease mechanical stress during bone preparation. This study primarily compared systemic inflammatory biomarkers between bone-milling RA-TKA and conventional TKA (C-TKA), with secondary assessments of perioperative parameters, radiographic alignment, and early postoperative outcomes.

Methods: This prospective randomized controlled trial included 30 RA-TKAs and 30 C-TKAs performed between August 2023 and December 2024 in patients with Kellgren-Lawrence grade IV knee osteoarthritis. All RA-TKA procedures were conducted during the operating surgeon's early learning phase with the robotic platform. Serum interleukin (IL)-6, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), creatine kinase (CK), and lactate dehydrogenase (LDH) were measured preoperatively and at 6 h, 1 day, 3 days, 2 weeks, and 6 weeks postoperatively. Perioperative variables, radiographic alignment, and 6-week Knee Society Score (KSS) and visual analog scale (VAS) pain scores were compared.

Results: Postoperative inflammatory biomarkers did not differ significantly between groups at any time point, and the corresponding effect sizes were small, indicating minimal biological differences. Estimated blood loss was comparable (p = 0.753). RA-TKA demonstrated significantly improved postoperative mechanical alignment (mechanical axis [MA] deviation: 0.3 ± 2.4° versus 2.8 ± 3.4°; p = 0.002) but required longer tourniquet times (121.4 ± 15.3 min versus 95.0 ± 13.3 min; p < 0.001). Early functional outcomes were similar, with no significant differences in KSS (p = 0.114) or VAS pain scores at 6 weeks (p = 0.508).

Conclusions: Bone-milling RA-TKA did not reduce systemic inflammatory responses compared with C-TKA, with small effect sizes confirming minimal biological differences. However, it provided superior radiographic alignment, while perioperative parameters and early postoperative recovery remained comparable except for longer tourniquet time.

Background: The purpose of this systematic review and meta-analysis is to evaluate and compare the effects of anterior cruciate ligament reconstruction (ACLR), meniscal surgeries, and cartilage surgeries on return to sport (RTS) outcomes in professional soccer players.

Materials and methods: The methodology followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. An electronic database search was performed to identify potentially relevant research articles. Four different outcome measures (age at surgery, return to sport, time to return to sport, level of return to sport) were extracted and meta-analyzed from all included studies and compared from three different groups (ACLR, cartilage surgeries, meniscus surgeries).

Results: The pooled meta-analysis showed no difference in age at surgery among groups (p > 0.05). The overall pooled return-to-sport rate was 90% (95% CI 93.3-95.9), with no significant differences between ACL reconstruction, meniscus surgeries, and cartilage surgeries (p > 0.05) Patients treated for ACLR reported a longer time (p < 0.05) to return to sport (258.05 days; 95% CI 230.48-288.93) compared with meniscus (41.11 days; 95% CI 30.22-55.93) and cartilage surgeries (135.0 days; 95% CI 130.54-139.61). Furthermore, the pooled meta-analysis showed that athletes who underwent meniscus surgeries had a higher (p < 0.05) percentage of return to sport (100%: 95% CI 86.0-100.0) compared with ACLR (80.0%; 95% CI 67.5-90.3) and cartilage treatment (94.5%; 64.2-100.0).

Conclusions: For professional soccer players, ACL reconstruction, meniscus surgeries, and cartilage surgeries demonstrated a favorable RTP rate of around 90%. Nevertheless, the analysis of the level of RTS and the time to RTS was constrained by limited evidence, precluding a more objective conclusion.

Level of evidence: Meta-analysis of studies of Level IV.

Study registration: PROSPERO Registry (CRD420251074362).

Background: Knee osteoarthritis (KOA) is a leading cause of musculoskeletal disability. Beyond the well-established impairment of reduced strength, deficits in force control (steadiness and complexity) may also influence functional performance. This cross-sectional study investigated quadriceps strength, force steadiness and complexity in patients with KOA and their associations with functional performance.

Methods: A total of 48 patients scheduled for unilateral knee arthroplasty performed maximal voluntary isometric contraction in both limbs. A 2-s window from the trial containing the peak torque was used to compute quadriceps strength (average torque, AT), force steadiness (coefficient of variation, CV), and force complexity (sample entropy, SE; detrended fluctuation analysis alpha exponent). Functional performance was assessed via sitting-to-standing, single-leg stance, Timed Up and Go, and 30-s sit-to-stand tests. Comparisons between involved and contralateral limbs used analysis of variance (ANOVA) models, accounting for prior surgery in contralateral knees. Linear regression analyzed associations between functional performance and the lateral symmetry index (LSI) of AT and SE.

Results: Results showed significant differences between limbs for AT (P < 0.001, η² = 0.074) and SE (P = 0.041, η² = 0.046), with the involved knee exhibiting lower strength and higher complexity. Regression revealed a positive association between sitting-to-standing and 30-s sit-to-stand performance and LSI-AT (βs are equal to -0.337 and 0.336, respectively; P < 0.027), but no other links were found.

Conclusions: KOA is associated with between-limb asymmetries in quadriceps strength and force complexity, with the involved knee exhibiting deleterious alterations. Nonetheless, force complexity was not correlated with functional performance.

Background: Multiligament knee injuries (MLKI) are rare but severe, often associated with knee dislocation and carry a high risk of neurovascular complications. Although ligamentous reconstruction has been widely studied, there is limited evidence addressing the incidence and specific patterns of meniscal injuries in this setting.

Methods: We retrospectively analyzed skeletally mature patients admitted to a Level I trauma center between January 2022 and December 2024 with MLKI, with or without knee dislocation. Demographics, trauma mechanism, ligamentous, and meniscal injury patterns were reviewed on the basis of magnetic resonance imaging (MRI) and surgical records. Meniscal tears were classified by location and morphology. Statistical analysis included Fisher's exact test, chi-square tests, and univariate logistic regression with significance set at p < 0.05.

Results: A total of patients were included: 35 (63.6%) with knee dislocation and 20 (36.4%) without. Mean age was 36.8 ± 13.2 years, and 81.8% were male. Magnetic resonance imaging was performed at a mean of 28.1 ± 7.3 days after injury. High-energy trauma accounted for 69.1% of cases and was significantly associated with dislocation (p = 0.001). Medial meniscus tears in patients with dislocation were predominantly radial/complex/oblique (72.7% versus 0% in nondislocated, p = 0.004; OR not calculable due to perfect separation), while all nondislocated patients had longitudinal tears. Lateral meniscus tears showed a similar pattern, with radial/complex/oblique tears more frequent in dislocation (80.0% versus 20.0%, OR = 16.00, 95% CI 1.27-200.92, p = 0.031).

Conclusions: Knee dislocations demonstrate distinct meniscal tear patterns compared with nondislocated MLKI, with radial and complex tears predominating in dislocated knees. Recognition of these differences may assist in accurate diagnosis and individualized surgical planning.