Acute total ACL (N = 60) and concomitant medial collateral ligament (N = 46) ruptures were repaired in 60 patients (mean age, 28 years) without augmentation. Menisci were removed in 23 knees. Fifty-three (88%) of the patients were reexamined 9 to 16 years later with special emphasis on manual and instrumented stability testing (Stryker, Genucom), knee function score (Lysholm), and activity level (Tegner). Standing roentgenograms (30 degrees of knee flexion) were taken in 69% of the patients. At followup, an ACL reconstruction had been performed in seven patients (12%) due to symptomatic instability. Sixty-four percent of the knees had a positive Lachman sign and 40% a positive pivot shift. Sagittal laxity difference was +3 mm or more in 57%. Knee function score was a mean of 86 +/- 12 points. The mean activity level had changed from recreational team sports (Level 7) to recreational individual sports (Level 5). Only patients with good knee stability were able to perform demanding sports and could continue at their desired activity level. Osteoarthritis of slight to moderate degree (Fairbank I/II) was found in 58% of the patients younger than 35 years of age at the time of trauma and in 87% of the older patients. Knees with intact menisci had less osteoarthritis than knees with removed menisci (P less than 0.05).