Acute anterior cruciate ligament injuries can be repaired through conservative treatment with early protective motion: a single-group cohort study.

Objectives: Early protective motion (EPM) treatment, using a rigid functional knee brace for acute anterior cruciate ligament (ACL) injuries, has been reported to restore ACL function. This study aimed to investigate the probabilities of return to sports and reinjury rate associated with EPM treatment and the result of restoring ACL function and morphology in MRI more than 2 years after injury in patients with acute injured ACL. Methods: This study included sports players with primary acute ACL injuries, straight-shaped tears and normal-volume bands on sagittal MRI, with a minimum of 2-year follow-up. If the ACL is treatable based on MRI, Lachman test and KT-1000 measurements after 3 months of knee brace use, EPM treatment can continue. The time of RTS, reinjury rate and KT measurements before and after treatment were analysed. In addition, the reinjury group and the non-reinjury group were compared. Results: Thirty-one patients participated in this study. KT measurements at injury, brace removal and final follow-up were 5.8 mm (IQR, 4.5-7.0), 0.0 mm (IQR, -0.5-0.5) and 0.0 mm (IQR, 0.0-0.5), respectively. 77.4% returned to sports at their preinjury level and had ACL repair on MRI after more than 2 years post-injury. Reinjury occurred in 22.6%, with no significant demographic differences between the reinjury and non-reinjury groups. Conclusion: After EPM treatment with at least 2 years of follow-up, 77.4% of patients returned to sports with restored ACL function. MRIs taken over 2 years post-injury confirmed ACL morphology repair, following strict case selection based on MRI within 2 weeks of injury.