ACL reconstruction is increasingly proposed for over-50 year-olds, although surgery had a poor reputation in this age-group, mainly due to postoperative stiffness. ACL reconstruction results were compared between two prospective series of, respectively, over-50 year-old (group 1) and under-40 year-old patients (group 2). The main study hypothesis was that ACL surgery provides the same functional results after 50 as before 40 years of age, and the secondary hypothesis was that the rate of complications does not differ.

A multicenter prospective non-randomized follow-up study included 228 over-50 year-old and 130 under-40 year-old patients in 10 public and private sector centers.

Epidemiological data were collected. Clinical laxity, differential laxity, KOOS, IKDC, Tegner and ACL-RSI scores and radiologic aspect were assessed pre- and post-operatively. Early (<3 months) and late (>3 months) complications were collected. Functional scores were compared between groups at last follow-up: 14.2 months (range, 3.5-30.5 months in group 1, and 20.5 months (range, 11.4-29.4 months) in group 2.

Analysis of epidemiological data showed some inter-group differences: female predominance in group 1 (59% versus 35%), longer trauma-to-surgery time in group 2 (23.6 versus 8.7 weeks), predominance of pivot-contact (team) sports in group 2 (49% versus 6%), and predominance of pivot sports (skiing) in group 1. Tegner scores were lower in group 1 (5.2 versus 7.6). Meniscal lesions were more frequent in group 1 (68% versus 36%), as were cartilage lesions (76% versus 10%). Initial laxity levels were identical (6.5mm in group 1 and 6.7mm in group 2). Type of surgery was identical: 86% hamstring graft in group 1 and 89% in group 2. There were more early complications (hematoma) in group 1; rates of late complications were comparable. Laxity at last follow-up was 2.2mm in both groups, and thus Lachman and pivot-shift test results were identical in terms of firm end-feel and absence of pivot shift. Quality-of-life assessment found higher KOOS scores in group 2, although ACL-RSI scores were identical. Global IKDC scores were slightly better in group 2, due to osteoarthritis in the older patients.

ACL reconstruction after 50 years of age gave good results, correcting laxity as effectively as in under-40 year-olds, with identical technique and identical rates of complications. Time to return to sports and resumed level were comparable.

III, prospective comparative non-randomized.