• ABSTRACT
    • Tears of the medial collateral ligament (MCL) are the most common knee ligament injury.Incomplete tears (grade I, II) and isolated tears (grade III) of the MCL without valgus instability can be treated without surgery, with early functional rehabilitation.Failure of non-surgical treatment can result in debilitating, persistent medial instability, secondary dysfunction of the anterior cruciate ligament, weakness, and osteoarthritis.Reconstruction or repair of the MCL is a relatively uncommon procedure, as non-surgical treatment is often successful at returning patients to their prior level of function.Acute repair is indicated in isolated grade III tears with severe valgus alignment, MCL entrapment over pes anserinus, or intra-articular or bony avulsion. The indication for primary repair is based on the resulting quality of the native ligament and the time since the injury. Primary repair of the MCL is usually performed within 7 to 10 days after the injury.Augmentation repair for the superficial MCL (sMCL) is a surgical technique that can be used when the resulting quality of the native ligament makes primary repair impossible.Reconstruction is indicated when MCL injuries fail to heal in neutral or varus alignment. Reconstruction might be advisable to correct chronic instability. Chronic, medial-sided knee injuries with valgus misalignment should be treated with a two-stage approach. A distal femoral osteotomy should be performed first, followed by reconstruction of the medial knee structures. Cite this article: EFORT Open Rev 2018;3:398-407. DOI: 10.1302/2058-5241.3.170035.