Purpose: Disruption of the medial patellofemoral ligament (MPFL) is now considered the essential lesion of recurrent lateral patellar dislocation in patients with normal lower extremity alignment. Reconstruction of the MPFL is a technique gaining significant success in the treatment of patients with this disabling condition.
Hypothesis: Reconstruction of the MPFL in patients with chronic patellar instability and normal lower extremity alignment will improve knee function and symptoms, with a high percentage of patients achieving good to excellent results at early follow-up.
Study design: Case series; Level of evidence; 4.
Methods: A consecutive series of patients with lateral patellofemoral instability who underwent MPFL reconstruction were reviewed. Reconstruction was performed with either soft tissue allograft (23 patients) or hamstring tendon autograft (12 patients). Outcomes were determined by patient scores from the Kujala Anterior Knee Pain Scale, recurrence of patellar instability, and patient function at a minimum of 12 months of postoperative follow-up.
Results: Thirty-five patients were followed for a mean of 21.0 months (range, 12-45 months) after surgery. The Kujala subjective knee score improved significantly from 49.0 preoperatively to 89.5 postoperatively (P < 0.001). No statistical significance was found between postoperative Kujala scores and graft type, or time from initial injury to surgical reconstruction. A firm endpoint to lateral translation of the patella, and no feelings of apprehension were noted in all patients at most recent follow-up. The majority of patients noted that they were more active than before reconstructive surgery, with 86% participating in "strenuous" to "very strenuous" activities at the time of follow-up. No recurrent dislocations were reported.
Conclusion: Reconstruction of the MPFL provides excellent stability and functional outcomes for patients with recurrent patellar instability.