Evaluation and treatment of medial instability of the knee.

Medial knee ligament injury and instability has frequently been treated by bracing and physical therapy. That has worked well in many instances and patients have been able to resume preinjury activities. However, there is a subset of patients that remain unstable when treated with conservative measures. A critical question we face is why these knees fail when the majority heal well and regain function? What are the differences that lead to failure and how can surgeons recognize these differences and determine which patients will benefit from primary surgical repair or reconstruction?