Summary

Delayed ACL reconstruction may reduce the odds by 10 to 14% for return to preinjury activity level for every month delay in patients with an ACL injury regardless of activity level before ACL injury and regardless of age at 12 months after surgery.

Abstract

Purpose

To examine the effects of timing of anterior cruciate ligament (ACL) reconstruction on the odds to recover muscle (quadriceps and hamstring) strength, return to preinjury physical activity level, and achieve rehabilitation goals at 12 months follow-up.

Methods

Data were extracted from a local rehabilitation registry in Sweden in November 2023. Patients ≥16 years old who underwent primary ACL reconstruction with hamstring tendon autografts, who underwent isokinetic muscle strength assessment, and responded to patient-reported outcomes 12-months after surgery were included. A multivariable logistic regression analysis was used to analyze the association between timing of ACL reconstruction and the recovery of muscle strength, return to preinjury physical activity level, and achievement of rehabilitation goals. The results of the logistic regression analysis were expressed as odds ratios (OR) for every 1-unit increase in the predictor variable (months between ACL injury and reconstruction).

Results

In total, 715 patients were included, of which 53.4% (n=383) were women. The mean age at ACL reconstruction was 28.3±10.5 years, and the median time between ACL injury to reconstruction was 4.9 months (IQR 2.9;9.4). Every month delay of ACL reconstruction significantly decreased the odds of returning to preinjury physical activity level at 12 months by 10 to 14% irrespective of activity level preinjury and age. Shorter median time in months from ACL injury to reconstruction was observed in younger patients, 16-30 years old, (3.9 [IQR 2.5;6.5] versus 4.7 [IQR 2.9;9.1], p=0.007) and in patients who participated in pivoting activities (Tegner scale 6-10) preinjury (3.4 [IQR 2.3-6.2] versus 5.0 [IQR 2.9-9.7], p<0.001).

Conclusion

Delayed ACL reconstruction may reduce the odds by 10 to 14% for return to preinjury activity level for every month delay in patients with an ACL injury regardless of activity level before ACL injury and regardless of age at 12 months after surgery.