Delayed anterior cruciate ligament reconstruction and risk of meniscus injury: Exploring the safest delay interval.

PURPOSE

The duration for which anterior cruciate ligament reconstruction (ACLR) can be delayed without resulting in a risk of subsequent meniscus injury has remained a debatable topic. The main purpose of this study was to determine the safest delay interval for a delayed ACLR.

METHODS

This retrospective study included all patients who underwent ACLR between January 2020 and January 2022. The patients were divided into four groups based on the delay interval: <3 months, 3-6 months, 6-12 months and >12 months. Clinical outcomes were assessed using the International Knee Documentation Committee (IKDC) score and Knee Injury and Osteoarthritis Outcomes Score (KOOS) at 1-year postoperatively.

RESULTS

A total of 95 patients were included in this study. ACLR delay of 3-6 months was not associated with the risk of meniscus injury, while a delay of 6-12 months (odds ratio [OR] = 4.35; 95% confidence interval [CI] = 1.13-16.79;  = 0.031) and >12 months (OR = 10.68; 95% CI = 2.55-42.22;  = 0.001) was associated with a likelihood of developing meniscus injury. Meniscus injury risk increased by 12% for each month of ACLR delay (OR = 1.12; 95% CI = 1.04-1.22;  = 0.003). Regarding clinical outcomes at 1-year postoperatively, all groups exhibit the same clinical results.

CONCLUSION

ACLR can be safely delayed up to 6 months after the initial injury. However, a delay for >6 months must be avoided, as it was found to significantly increase the likelihood of developing a meniscus injury.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.