Treatment of Chronic Collateral Knee Injuries

Chronic Lateral Collateral Injuries Lateral collateral ligament (LCL), popliteus tendon and popliteo-fibular ligament (PFL) are the main static stabilizers on the lateral side of the knee and resist abnormal varus and external rotation. Isolated injuries of the lateral stabilizing structures are rare and most of the injuries are associated with damage to the ACL or PCL. Unrecognized posterolateral injury also places abnormal loads on ACL or PCL grafts and might lead to early failure of the reconstruction. Management of chronic lateral injuries starts with a thorough clinical examination of the knee ligaments with special emphasis on varus stress test, dial test and postero-lateral drawer test in varying degrees of knee flexion, and varus-hyperextension thrust during walking. Stress X-rays are helpful to quantify the amount of laxity. Weight-bearing full length radiographs are mandatory since varus extremity alignment leads to abnormal loads on the lateral reconstruction and should be corrected before ligament surgery is attempted. It is important to distinguish between varus alignment due to lateral laxity and tibial metaphyseal varus, since only the latter needs corrective osteotomy.