Medial patellofemoral ligament reconstruction with gracilis autograft for recurrent patellar instability: a case report

The medial patellofemoral ligament (MPFL) is the primary passive restraint in pathologic lateral translation of the patella. Recurrent patellar instability is com­mon, and multiple procedures have been described for its treatment. Chronic instability of the patellofemoral joint and recurrent dislocation may lead to progres­sive cartilage damage and severe arthritis if not treated adequately. A 17-years-old female presented with a one-year history of knee pain in his left knee. The apprehension test is positive; there is pain and muscle defensive contraction of lateral patellar dislocation with 20°-30° of knee flexion. MRI revealed flattened trochlear joint surface proximally and the concavity is less pronounced distally. The inclination angle is less than 11 degrees and trochlear facet asymmetry can be seen on axial view. Patient undergone medial patellofemoral ligament reconstruction with gracilis autograft and six months postoperatively, the patient was followed up using WOMAC score and showed good result. WOMAC score was 96.2% indicating no significant pain, joint stiffness, or any difficulty on physical activity. After the operation, the patient is able to perform regular daily activities without any complaints. This study has shown that treatment of recurrent patellar instability with medial patellofemoral ligament reconstruction using gracilis autograft resulted in satisfactory functional outcome based on WOMAC score