Journal of ISAKOS Joint Disorders & Orthopaedic Sports Medicine最新文献

Introduction: Patellofemoral maltracking is a leading cause of anterior knee pain (AKP), yet current diagnostic paradigms largely focus on distal alignment parameters while the contribution of proximal skeletal morphology remains unclear. Pelvic width (PW) has been hypothesized to influence femoral orientation and extensor mechanism alignment; however, its relationship with patellofemoral alignment is poorly defined, particularly in Asian populations where pelvic morphology differs from Western cohorts. This study aimed to evaluate the association between PW and radiological patellofemoral alignment parameters, and to assess sex-based differences in pelvic morphology and patellofemoral characteristics in patients with AKP.

Methods: A cross-sectional study was conducted involving 100 consecutive patients (50 men, 50 women; age 17-65 years) presenting with AKP. Full-length standing scanograms were used to measure PW (distance between bilateral anterior superior iliac spines), and hip-knee-ankle (HKA) angle. Noncontrast 3.0-T knee magnetic resonance imaging (MRI) was performed to assess patellar tilt angle (PTA), sulcus angle (SA), tibial tubercle-trochlear groove (TT-TG) distance, Insall-Salvati (IS) ratio, and bisect offset (BO). Continuous variables were compared between sexes using appropriate parametric or nonparametric tests based on data distribution. Correlations between PW and patellofemoral parameters were assessed using Spearman's rank correlation. Key patellofemoral parameters were additionally analyzed categorically using established clinical thresholds, with between-sex comparisons performed using Fisher's exact test.

Results: Pelvic width did not differ statistically significantly between male and female patients and showed no statistically significant association with patellofemoral alignment or tracking parameters, whether analyzed as continuous variables or categorical groups. No correlations were observed between PW and all patellofemoral parameters group. In contrast, females demonstrated a statistically significant higher prevalence of shallow SA (≥145°) compared with males (P < 0.05). Secondary analyses revealed statistically significant strong correlations among established patellofemoral parameters including between PTA category and BO category, and between TT-TG category and BO category, confirming internal biomechanical coherence.

Conclusions: Pelvic width neither differs by sex nor statistically significantly influences patellofemoral alignment or maltracking in Asian patients with AKP, whereas local patellofemoral morphology-particularly trochlear anatomy-appears to be the primary structural determinant of patellofemoral pain.

Level of evidence: III Observational Studies.

Introduction/objectives: Patellofemoral arthroplasty (PFA) is a joint-sparing alternative to total knee arthroplasty (TKA) for isolated patellofemoral osteoarthritis, offering symptom relief while preserving tibiofemoral compartments and bone stock compared with TKA, particularly in younger and active patients. However, persistent anterior knee pain and patellar instability remain leading causes of early failure, even when prosthetic components are stable and tibiofemoral degeneration is absent. This study aimed to describe a combined, non-prosthetic surgical strategy for symptomatic PFA failure due to patellar instability and to propose an algorithm-based framework for clinical decision-making.

Methods: A 54-year-old woman presented with chronic anterior knee pain and recurrent instability four years after isolated PFA. Imaging confirmed stable and well-aligned prosthetic components with preserved tibiofemoral compartments but consistent lateral patellar subluxation. The patient was treated using a joint-preserving approach combining medial patellofemoral ligament (MPFL) reconstruction with hamstring autograft, anteromedial tibial tubercle osteotomy, and vastus medialis obliquus (VMO) advancement. Clinical outcomes were assessed with the Kujala and International Knee Documentation Committee (IKDC) scores at six weeks and three months.

Results: At three months, the Kujala score improved from 54 to 78, and the IKDC subjective score increased from 38 to 69. The patient reported significant pain reduction, restoration of patellar stability, and functional recovery. No recurrent instability, surgical complications, or implant-related problems were observed. Radiographs confirmed correct alignment and congruent prosthetic components.

Conclusion: A combined approach addressing soft-tissue, bony, and dynamic stabilizers may provide an effective, joint-preserving alternative to total knee arthroplasty in selected patients with symptomatic PFA failure caused by instability. The algorithm presented may assist in surgical decision-making and optimize patient outcomes.

Level of evidence: V.

Lateral bucket-handle meniscus tears are challenging to reduce and repair due to limited visualization of the posterior compartment and the risk of iatrogenic injury. We present an arthroscopic workflow that combines standard anterior portals with an intercruciate trans-septal route to enhance visualization and working space across the posterior compartments of the knee. Key steps include safe creation of posteromedial and posterolateral apertures, protected posterior portals, and guided passage of a Wissinger rod to connect compartments prior to reduction and fixation. Reduction is performed with careful meniscal preparation and controlled manipulation; fixation is achieved primarily with all-inside sutures, with optional inside-out reinforcement for stiffer or chronic tears. This technique serves as an alternative approach in selected cases where visualization is limited. This article details indications, contraindications, safety pearls, limitations, early institutional experience, and expected complications to support safe adoption of the technique.

Total knee arthroplasty (TKA) is a successful treatment for knee osteoarthritis, with up to 92% implant survival at 20 years. This success has led to its increased use in younger patients (under 55), who benefit from early pain relief and improved quality of life, but face higher revision risks due to prolonged implant exposure, higher activity levels, and mechanical loading over time. Biokinetic stresses from sports and other high-demand activities are a critical yet often overlooked factor, as decades of repetitive loading may influence long-term outcomes. This narrative review summarizes recent evidence from English-language consensus statements and systematic reviews on implant survivorship, revision risk factors, sports participation, and biomechanical considerations in younger TKA patients. Implant survivorship rates in younger patients are 52.1% to 65.3% after 40 years. Higher revision rates are linked to varus alignment, increased posterior tibial slope, thinner polyethylene inserts, and fewer comorbidities. Low-impact sports like cycling and swimming are encouraged post-TKA, while high-impact sports should be approached cautiously. Biokinetic risk factors, such as altered gait patterns (e.g., stiff-knee gait, dynamic valgus, and increased flexion moment), warrant both preoperative and postoperative motion analysis and may be particularly important in younger patients, given their longer duration of implant use. In summary, young patients undergoing TKA can generally expect excellent implant survivorship, functional outcomes, and satisfaction. Specific risk factors for revision in this population require careful attention. Although current evidence does not link sports participation to increased revision rates or implant wear in the short to mid-term, the combination of long-term implant use and increased mechanical loading during activities represents an important frontier and ongoing challenge in the field. LEVEL OF EVIDENCE: Not Applicable [Current Concepts Review].