Effectiveness analysis of arthroscopy-assisted medial retinaculum tightening suture with internal fixation for treating adolescent acute patellar dislocation with osteochondral fracture: A retrospective study

This study aims to investigate the therapeutic effectiveness of arthroscopically assisted medial retinaculum tightening suture, coupled with internal fixation, in managing acute patellar dislocation (APD) complicated by osteochondral fracture (OCF) in adolescent patients. We retrospectively analyzed the clinical data of 20 adolescents with APD with OCF who underwent arthroscopically assisted medial retinaculum tightening suture with internal fixation between April 2018 and April 2023. Eligible patients were younger than 20 years and had radiologically and arthroscopically confirmed osteochondral defects of the patella treated by fixation. Patients with previous patellar dislocation, ligament injuries, or preexisting patellofemoral osteoarthritis were excluded. The primary outcome was improvement in patellofemoral function, we evaluated the patient’s range of motion, clinical functional recovery, and pain alleviation by comparing the patellar tilt angle, lateral patellar displacement, Kujala Patellofemoral Joint score, Lysholm Knee score, International Knee Documentation Committee Motion Level score, and Visual Analogue Scale at preoperative, 3 months, and 1 year after surgery. The secondary outcome was to assess the thickness of the patellar cartilage in both knees using bilateral knee MRI scans and to evaluate early degenerative changes. For continuous variables that adhered to a normal distribution, either a t test or repeated-measures ANOVA was applied; Friedman test was used for continuous variables that did not conform to a normal distribution, with P < .05 considered statistically significant. Twenty adolescents were included, with a mean follow-up of 36.15 ± 12.42 months. Patellar tilt angle and lateral patellar displacement improved from 23.55 ± 6.73° and 21.39 ± 4.51 mm preoperatively to 11.23 ± 5.05° and 12.25 ± 4.55 mm at 3 months, and remained stable at 1 year (all P < .001 vs preoperative; P > .05 vs 3 months). At 3 months, Kujala, Lysholm, International Knee Documentation Committee, and Visual Analogue Scale scores were 64.80 ± 3.72, 67.60 ± 3.53, 82.70 ± 3.31, and 2.00 (1.00–3.00), all improved versus baseline ( P < .001), with further improvement at 1 year ( P < .001). No redislocation, subluxation, or significant patellar cartilage thinning versus the contralateral knee was observed on MRI. Arthroscopy-assisted medial retinaculum tightening suture with internal fixation provides reliable mid-term restoration of patellofemoral stability and function in adolescents with APD and OCF, without evidence of early patellar cartilage degeneration, and may represent a useful alternative option to medial patellofemoral ligament reconstruction in this population.