Restoration of normal knee function. Acute avulsion of the anterior cruciate ligament (ACL) from its femoral origin. Mid substance and remote tears. Supine. Knee flexed, hip bent to 30°. General or regional anaesthesia. Step 1: Arthroscopy to confirm site of rupture, meniscus repair if necessary. Step 2: Mobilisation of semitendinosus tendon, left attached distally. Step 3: Mini-arthrotomy, securing of ACL stump with atraumatic suture. Step 4: Transfer of ST-tendon through 5 mm drill holes through tibial head and lateral femoral condyle. Step 5: Fixation of tendon and ACL-sutures with staple at the exit of the femoral drill hole. Knee orthosis for 6 weeks, CPM, physiotherapy. ROM day 0–2: 0-10-10°; day 3–11: 0-0-60°, day 12–42: 0-0-90°. Increase of weight bearing 10 kg/week from operation date. Bicycling and running permitted 3 months post-op. Full sport activity after muscle power has reached that of opposite side. LMW heparin until full weight bearing. Thrombosis. Embolism. Infection. Failure of reconstruction. Osteoarthritis. During 1 year, 116 patients were operated. Follow-up after 42 to 57 months (average 52 months) included 95 patients (82%). Of these, 76 underwent full examination (average age 33 1/2 years, 20–49 years), 11 answered a questionnaire, 8 had suffered re-injury. Average Lysholm score was 92 points (±13). Tegner activity scale amounted to 7.2 points pre-injury, 7.1 points at follow-up. Anterior translation (KT 1000 arthrometer testing at 89 N) was identical to opposite side in 25 patients, less than 2 mm in 14, up to 4 mm in 19, up to 6 mm in 15, more that 6 mm in 3 patients. Pivot shift was negative or trace 73 times, and positive in 3 patients. ROM was full in 54 patients, 17 times the flexion was limited up to 10°. Ten times extension lag was less than 5°, and twice between 5 and 10°.