Ten-year prognosis of isolated and combined medial collateral ligament ruptures. A matched comparison in 40 patients using clinical and radiographic evaluations.

In a matched-pair study of 40 patients, the prognoses of patients with acute isolated partial medial collateral ligament injuries and acute combined medial collateral and anterior cruciate ligament injuries were compared 10 years after initial treatment. All patients in the first group were treated nonoperatively. In the latter group, most medial collateral ligament injuries were total ruptures, which were thoroughly repaired; the torn anterior cruciate ligament was repaired with augmentation in half of the cases. At the follow-up evaluation, both patient groups had similarly high knee functions according to the Lysholm score and similar activity levels (recreational team sports). Knees with combined injuries had increased sagittal laxity at manual and instrumented assessment. Radiographic signs of knee osteoarthritis were present in half of the knees with combined injuries, but they were absent in knees with isolated injuries. The long-term functional prognosis was similarly good after isolated or combined medial collateral ligament injuries, but patients with combined ruptures had more reinjuries and repeat surgeries, increased sagittal laxity, and a higher incidence of radiographic osteoarthritis.