Extension deficit after ACL reconstruction: Is open posterior release a safe and efficient procedure?

Extension loss is a potentially devastating consequence of anterior cruciate ligament reconstruction (ACLR). It can often be treated by anterior arthroscopic release. In rare cases, a chronic flexion contracture requires an additional posterior open release. To our knowledge, no study analysing the results of both posteromedial and posterolateral approaches has been performed so far. The purposes of this study were (1) to analyse the midterm outcome and complications of a combined procedure, anterior arthroscopic debridement and posterior open capsulotomy - for the treatment of chronic extension deficits after ACLR and (2) to describe the surgical technique of posterior open release with both posteromedial and posterolateral approaches.

This is a retrospective clinical cohort study. Twelve patients presenting a chronic flexion contracture of 10° or more after ACLR treated by open posterior arthrolysis with an average follow-up time of 38months (range six to 90) were included. At last follow-up, they underwent both a clinical examination with range of motion analysis, International Knee Documentation Committee (IKDC) and KOOS scores.

At follow-up, all patients except one (93%) achieved complete extension. Only one patient (7%) had a residual post-operative flexion deformity of five degrees. The range of motion (ROM) improved significantly after arthrolysis from 96°±14.3° (SD) to 14.3°±7°(SD)(p<0.001). No post-operative complications were recorded. No patients required further open debridement. The post-operative objective IKDC score was grade A for five patients, B for seven versus C for five patients and D for seven preoperatively. The mean post-operative subjective IKDC score was 86.4±9.7. The post-operative Knee injury and Osteoarthritis Outcome Score (KOOS) distribution was as follows: pain 93.8±5 (SD); symptoms 88±8.6 (SD); ADL 96.8±3.7 (SD); sports activities 83.6±12.3 (SD); and quality of life 82.9±8.8 (SD). Mean patients' satisfaction was 9.25±0.6 (SD) out of 10 after arthrolysis.

Open posterior release with both posteromedial and posterolateral approaches is a safe and efficient additional procedure in case of persistent flexion contracture after ACLR with good ROM gain, functional scores and patients' satisfaction.

Therapeutic study - Level IV.