Return to Sport After Revision ACL Reconstruction: A Comparative Cohort Study of Outcomes After Single- Versus Multiple-Revision Surgeries

BACKGROUND: The return-to-sport rate at 2 years after multiple-revision anterior cruciate ligament (ACL) reconstructions has not been evaluated. HYPOTHESIS: It was hypothesized that patients who undergo multiple-revision ACL reconstructions would have a lower return-to-sport rate at 2 years after surgery than those who undergo a single-revision reconstruction. Furthermore, it was hypothesized that the multiple-revision group would have lower functional scores. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A single-center cohort study in patients who underwent revision ACL reconstruction was begun in 2012. This study included 2 groups: Patients who underwent a single revision, and those who underwent multiple revisions. The main evaluation criterion was the return to sport at the 2-year follow-up. The secondary criteria were the International Knee Documentation Committee (IKDC), Knee injury and Osteoarthritis Outcome Score (KOOS), Lysholm, and ACL–Return to Sport after Injury (ACL-RSI) functional knee scores at the 1- and 2-year follow-ups. RESULTS: A total of 322 patients (single-revision group: n = 302; multiple-revision group: n = 20) were included. A significant difference in the percentage of patients who stopped all sports activity was found between the 2 groups at 2 years (single-revision group: 19.4%; multiple-revision group: 50%). The return-to-sport rate at the same or lower level of performance was higher in the single-revision group as well (17% vs 14.3% for return at the same level; 45.6% vs 14.3% for return at a lower level; P = .03). At the 2-year follow-up, the functional scores of the single-revision group were significantly higher those than in the multiple-revision group: IKDC (77.7 ± 13.82 vs 64.79 ± 15.22; P < .001), KOOS (72.66 ± 17.63 vs 52.5 ± 15.64; P < .001), Lysholm (84.05 ± 11.88 vs 72.5 ± 13.49; P < .001), and ACL-RSI (52.34 ± 21.83 vs 46.43 ± 14.8; P = .0036). CONCLUSION: Only a small percentage of patients returned to the same level of sport after single- revision and multiple-revision ACL reconstruction, yet significantly more in the former. More patients who underwent multiple revisions gave up their sport. Functional scores were higher for single-revision than multiple-revision surgeries.