Short-term clinical and radiographic outcomes after isolated medial patellofemoral ligament reconstruction for recurrent and first-time traumatic patellar dislocation with severe trochlear dysplasia, increased tibial tuberosity–trochlear groove dista

PURPOSE: To report the clinical and radiographic outcomes of isolated medial patellofemoral ligament (MPFL) reconstruction in patients with recurrent or first-time traumatic patellar dislocation accompanied by multiple anatomical risk factors. METHODS: This retrospective study included 27 patients (27 knees) with a mean age of 22.70 ± 6.27 years (range, 14-35 years) who underwent isolated MPFL reconstruction between June 2019 and December 2023. All patients presented with severe trochlear dysplasia (Dejour types B-D), increased tibial tuberosity-trochlear groove (TT-TG) distance (>20 mm), patella alta (Caton-Deschamps index ≥ 1.2), and lower extremity torsion deformities (femoral anteversion ≥ 25° or external tibial rotation ≥ 30°). Clinical outcomes were evaluated using International Knee Documentation Committee (IKDC), Lysholm, Kujala, and Tegner scores. Radiographic parameters (patellar tilt angle (PTA) and lateral patellar displacement (LPD)) were measured on CT scans preoperatively and postoperatively. Return to sports, patient satisfaction (numeric rating scale 0-10 and categorical grades), redislocation rate, and complications were recorded at final follow-up. RESULTS: Mean follow-up was 3.14 ± 1.15 years (range, 1-4.42 years). The mean TT-TG distance was 22.22 ± 1.58 mm (range, 20.32-25.91 mm), the mean Caton-Deschamps index (CDI) was 1.41 ± 0.18 (range, 1.22-2.01), the mean femoral anteversion angle was 29.28° ± 3.88° (range, 25.26°-35.41°) and the mean external tibial rotation angle was 35.42° ± 4.54° (range, 30.62°-47.07°). All functional scores improved significantly (P < .001): Kujala (49.30 ± 9.36 to 87.85 ± 4.59), Lysholm (51.41 ± 9.61 to 88.63 ± 5.71), IKDC (44.46 ± 8.69 to 83.04 ± 3.86), and Tegner score (from 2.00 ± 1.03 to 3.67 ± 0.92). PTA decreased from 24.02 ± 7.07° to 7.31 ± 3.45° and LPD decreased from 10.55 ± 4.33 mm to 0.11 ± 6.28 mm (P < .001). One patient had postoperative subluxation and one experienced redislocation after direct trauma. Mean subjective satisfaction was 8.72. CONCLUSIONS: Isolated MPFL reconstruction provides satisfactory short-term clinical outcomes with a low redislocation rate in patients with patellar instability and multiple severe anatomical risk factors.