Repair and reconstruction of rotatory instability of the knee.

We studied the results of treatment in 110 of 129 consecutive patients who had knee instability for which they underwent reconstruction of the knee ligaments at the Mayo Clinic. Thirty-one patients underwent different types of extraarticular reconstruction. Nine (29%) had recurrence of the knee giving way, and 11 (36%) had objective signs of instability on examination. Fifty-five patients underwent combined extraarticular and intraarticular reconstruction with either the Lam-Jones patellar tendon (PT) procedure (21 knees) or the Zarins-Rowe semitendinosus and iliotibial band (ST & ITB) procedure (34 knees). Only two knees (10%) with PT procedure and three knees (9%) with ST & ITB procedures continued to have giving way. Three patients in each group had recurrence of instability. Twenty-four knees with acute instability had either primary repair (17 knees) or primary reconstruction with ST & ITB procedures (7 knees). The results in these knees were superior to the results in the knees reconstructed for chronic instability. On the basis of our 2 year results, we believe that a combined intraarticular and extraarticular reconstruction is the procedure of choice in chronic knee instability and is a useful procedure in acute knee instability with irreparable tears of the anterior cruciate ligament.