No increased occurrence of osteoarthritis after anterior cruciate ligament reconstruction after isolated anterior cruciate ligament injury in athletes

Purpose: To evaluate the long-term radiographic and clinical results of anterior cruciate ligament (ACL) reconstruction by comparing the injured knee with the contralateral knee in athletes with isolated ACL tear returning to preinjury sports.

Methods: Twenty-eight patients with isolated ACL tears without concomitant injuries at baseline returning to previous sports were selected. ACL reconstruction was performed with patella or hamstring tendon graft. Conventional radiographs and a 3-T magnetic resonance imaging study of both knees were obtained at a mean follow-up of 10 years after ACL reconstruction and were compared with each other. The International Knee Documentation Committee score and Tegner activity index were used for clinical evaluation and the Knee Injury and Osteoarthritis Outcome Score for evaluating self-reported knee function.

Results: The 3-T magnetic resonance imaging study showed positive signs of osteoarthritis in 33% of operated knees and 39% of nonoperated knees (P = .64). Conventional radiographs showed ongoing signs of radiographic osteoarthritis in 14% of uninjured knees according to Kellgren and Lawrence, in comparison with 21% of injured knees (P = .73). The functional outcomes between the injured knee and uninjured knee did not show any statistical differences. The mean postoperative International Knee Documentation Committee score was 89.2 ± 9.3 points, and the total Knee Injury and Osteoarthritis Outcome Score was 92.7 ± 7.8. The median preinjury Tegner score was 8 ± 2, corresponding to 7 ± 2 at follow-up. In 68% of patients, the Tegner score was unchanged from preinjury to follow-up.

Conclusions: Athletes with an isolated ACL rupture showed no increased risk of the development of post-traumatic osteoarthritis in the long-term after ACL replacement when compared with the uninjured contralateral knee. Our findings support the evidence to perform ACL replacement in athletes.

Level of evidence: Level IV, therapeutic case series.