Single-Bundle Medial Patellofemoral Ligament Reconstruction Using Adjustable-Length Loop Cortical Button Patella Fixation and Interference Screw Femoral Fixation.

Abstract

Many techniques have been described for the reconstruction of the medial patellofemoral ligament (MPFL) in patients with acute or recurrent instability. Most commonly, an MPFL hamstring tendon auto- or allograft is used, attached to the patella and medial femoral condyle using bone tunnels and various fixation implants to ensure stable fixation and graft healing. We describe a surgical technique in which an MPFL semitendinosus graft is inserted in a partial-width transverse patellar bone tunnel (typically 6-6.5 mm in diameter and 15-20 mm in length) and stabilized using adjustable loop cortical button fixation. In the femur, a tunnel is drilled in an oblique superolateral direction (typically 6-6.5 mm in diameter and 30 mm in length), and the graft is inserted and stabilized using an absorbable interference screw. The graft is tightened at 60° of knee flexion and retensioned after knee cycling as necessary, with the adjustable loop button. The described technique affords sufficient initial graft fixation strength, thereby eliminating the need for postoperative immobilization.