MRI assessment of growth disturbances after ACL reconstruction in children with open growth plates–Prospective multicenter study of 100 patients

Abstract

IntroductionWe were interested in the consequences of anterior cruciate ligament (ACL) reconstruction on the growth plates and the impact on growth in children with open growth plates. The primary objective was related to growth disturbances with the null hypothesis being that ACL reconstruction in open growth plates does not cause any. The secondary objective related to the presence of physis lesions on MRI, with the null hypothesis being that ACL reconstruction in open growth plates does not induce any. Material and MethodsIn the context of a 2017 SFA symposium on ACL reconstruction with open growth plates, we conducted a prospective multicenter study with 2 years’ follow-up. The study enrolled 100 patients; 71 were available for analysis. Four reconstruction techniques were used: semitendinosus-gracilis (STG), short graft (SG), quadriceps tendon (QT) and fascia lata (FL). MRI was used to look for growth disturbances as evidenced by deviation of the Harris lines or modification of the physis and diaphysis angles. Physis lesions were determined on MRI based on the presence of physeal bone bridges (PBB). ResultsNo growth disturbances were found. However, PBBs were found in 14 patients (20%). At the femur, the relative risk (RR) was higher when a STG graft was used (RR=2.1) and the tunnel diameter was≥9mm (RR=1.7). Epiphyseal fixation had a higher risk than transphyseal fixation (RR=1.6 vs. 1.2). At the tibia, the RR was higher when a QT graft was used (RR=3.6), when screw fixation was performed (RR=3.7) or when the graft did not fill the tunnel sufficiently (RR=1.5). DiscussionThe absence of growth disturbances after 2 years’ follow-up validates the possibility of ACL reconstruction with open growth plates, including with transphyseal techniques. The presence of small growth plate lesions such as bone bridges means that precautions should be taken with respect to tunnel trajectory, tunnel diameter, graft and tunnel diameter matching and graft fixation. Level of evidenceIII, prospective cohort study.