Anterolateral rotary instability of the knee joint. Results after stabilization by extraarticular transposition of the lateral part of the patellar ligament. A preliminary report.

A method using the lateral third of the patellar ligament and the adjacent part of the patella as an extraarticular transplant to the lateral femoral condyle in the stabilization of anterolateral rotary instability of the knee is described and discussed. The operation was performed in six patients. The stabilizing effect of the procedure could be evaluated in only five of them due to the development of septic arthritis in one patient. Four of these five patients had ruptured the anterior cruciate ligament, while the fifth patient had a congenital anterolateral instability. In this patient the procedure was combined with an Ellison operation. In all five patients the operation eliminated the instability and resulted in good function. The procedure is recommended for further testing in the treatment of anterolateral rotary instability of the knee as an alterative method to procedures applying the iliotibial band.