We measured the configuration of the femoral condyles on lateral radiographs in 100 consecutive, prospectively-studied patients with a complete rupture of the anterior cruciate ligament, with or without associated lesions of the menisci and collateral ligaments. The patients had mainly low-to-moderate activity demands, and in all the patients the cruciate tear was primarily treated non-operatively. A quotient was calculated from the measurements of sagittal depth and axial height in order to describe the geometry of the femoral condyles. Measurements were reproducible with an intra- and interobserver coefficient of correlation of 0.89-0.98. At follow-up, after 5 (3-6) years, 16 patients had developed disability leading to reconstructive surgery. The remaining 84 patients did not have any major functional limitations, but some had reduced their activity level. Individual variations in the articular geometry were found with a more spherical shape of the femoral condyles in the patients where non-operative treatment had failed. Our findings indicate that articular geometry is of importance for function after an anterior ligament lesion.

100 consecutive patients with a recent anterior cruciate ligament injury were examined with respect to type of sports activity that caused the injury, mechanism of injury and the occurrence of collateral ligament and meniscal lesions. There were 53 medial collateral ligament injuries, 12 medial, 35 lateral and 11 bicompartmental meniscal lesions. 59 patients were injured during contact sports, 30 in downhill skiing and 11 in other recreational activities, traffic accidents or at work. An associated medial collateral ligament tear was more common in skiing (22/30) than during contact sports (23/59), whereas a bicompartmental meniscal lesion was found more frequently in contact sports (9/59) than in skiing (0/30). Weightbearing was reported by 56/59 of the patients with contact sports injuries and by 8/30 of those with skiing injuries. Non-weightbearing in the injury situation led to the same rate of MCL tears (18/28) as those reporting weightbearing (35/72) but significantly more intact menisci (19/28 vs 23/72). Thus, contact sports injuries were more often sustained during weightbearing, with a resultant joint compression of both femuro-tibial compartments as shown by the higher incidence of bicompartmental meniscal lesions. This might be an important prognostic factor for future joint disease and arthrosis. The classic "unhappy triad" was a rare finding (8/100) and we suggest that this entity should be replaced by the "unhappy compression injury".