Short-term benefits of hybrid graft in medial patellofemoral ligament reconstruction for recurrent patellar dislocation: A prospective randomized controlled trial with minimum 2-year follow-up.

PURPOSE: This study aimed to compare short-term functional and radiological outcomes between autograft and hybrid graft reconstruction in medial patellofemoral ligament (MPFL) reconstruction for recurrent patellar dislocation and explore reasons for differences.

METHODS: This prospective randomized controlled trial enroled 51 patients with recurrent patellar dislocation undergoing MPFL reconstruction between January 2020 and January 2023. Major exclusions included severe trochlear dysplasia (Dejour Type B-D), open physis, patella alta, severe lower limb malalignment (knee valgus angle >20°, femoral anteversion >25° or external tibial torsion >30°) and tibial tubercle-trochlear groove (TT-TG) distance ≥20 mm. Patients were randomly assigned to autograft or hybrid graft groups; the hybrid graft comprised a semitendinosus tendon and 6-mm artificial ligament tape. The primary outcome was the 12-month Kujala score, prespecified for early functional recovery. Secondary outcomes included Kujala and International Knee Documentation Committee (IKDC) scores at other time points and imaging parameters (patellar lateral tilt [PLT] angle and patellar-trochlear groove [PTG] distance) preoperatively, immediately postoperatively and at final follow-up.

RESULTS: Forty-six patients were included in the final analysis (autograft, n = 22; hybrid graft, n = 24). Mean age was 19.3 years; 82.6% (38/46) were female. Baseline characteristics and preoperative functional scores were comparable between groups (all p > 0.05). Significant improvements in subjective knee scores were observed in both groups at 3, 6, 12 months and final follow-up (p < 0.05). At 3 months, mean Kujala and IKDC scores were 68.6 ± 5.2 and 68.0 ± 6.1 in the autograft group versus 82.4 ± 4.3 and 82.9 ± 3.3 in the hybrid graft group (both p < 0.001). At 6 months, corresponding scores were 83.4 ± 3.6 and 83.3 ± 3.3 versus 88.4 ± 4.6 and 88.0 ± 4.9 (both p < 0.05). No significant between-group differences were observed at 12 months or final follow-up (all p > 0.05). No significant between-group differences in PLT angle and PTG distance were observed immediately postoperatively or at final follow-up (all p > 0.05), with significant improvements from preoperative values in both groups (p < 0.05).

CONCLUSION: In carefully selected patients with recurrent patellar dislocation, MPFL reconstruction using a hybrid graft achieved satisfactory short-term clinical and radiographic outcomes and was associated with improved early functional recovery at 3 and 6 months. The hybrid graft may be a feasible option for MPFL reconstruction.

LEVEL OF EVIDENCE: Level II.