Medial patellofemoral ligament repair restores stability in pediatric patients when compared to reconstruction.

Background: Pediatric patellar instability has a high recurrence rate with non-operative care, and medial patellofemoral ligament (MPFL) reconstruction has known complications. MPFL repair offers an alternative method to restore patellar stability. This study's purpose was to assess the outcomes of MPFL repair in a pediatric cohort, and to compare these outcomes to a cohort of pediatric patients who underwent MPFL reconstruction.

Methods: One surgeon performed 16 MPFL repairs on pediatric patients for traumatic patellar instability, with an average follow-up of 1.5 years. Age, sex, skeletal maturity, trochlear dysplasia, additional procedures, final range of motion, and complications were recorded. A sub-cohort with >1 dislocation (10 patients) was compared to a historical group (22 patients) with >1 dislocation who underwent allograft MPFL reconstructions by the same surgeon.

Results: Ten out of 16 (63%) patients had >1 dislocation event at time of presentation. Thirteen out of 16 (81%) patients had trochlear dysplasia. There were no complications and no recurrent instability in the repair group at last follow-up. Patients in the reconstruction group were older than the repair group (15.6 years vs. 13.0 years, p < 0.05), had lower Caton-Deschamps ratio (1.2 vs. 1.4, p < 0.05), and had lower percentage of additional procedures (59% vs. 100%, p < 0.05). There were three complications in the reconstruction group: two patients with recurrent instability and one patient with patella fracture requiring revision surgery.

Conclusions: MPFL repair in pediatric patients resulted in a low risk of recurrent instability with rates comparable or better than that of allograft reconstruction.