Magnetic Resonance Imaging Evaluation of Physeal Violation in Adolescents After Transphyseal Anterior Cruciate Ligament Reconstruction.

PURPOSE: To quantify and compare the amount and location of physis violation of the distal femur and proximal tibia after transphyseal anterior cruciate ligament (ACL) reconstruction in skeletally immature patients.

METHODS: This study included 19 patients with open physes of the distal femur and proximal tibia who underwent ACL reconstruction with tibialis anterior allografts. Physeal tunnel volume and location on the growth plate, as well as obliquity to the growth plate, were measured by 3-dimensional postoperative magnetic resonance imaging of the distal femur and proximal tibia.

RESULTS: The percentage of physeal violation (ratio of the tunnel to the entire growth plate area) was similar for the distal femur and proximal tibia (3.95% vs 3.65%, P = .582). There were no differences in tunnel obliquity to the growth plate in the coronal (56.1° vs 71.6°, P = .061) and sagittal (85.9° vs 74.9°, P = .092) planes. The distal femoral tunnel was located 6.2% (17.2% vs 23.4%, P = .001) more peripherally in the anteroposterior direction and 9.7% (27.1% vs 36.8%, P < .001) more peripherally in the mediolateral direction than was the tibial tunnel.

CONCLUSIONS: The mean percentages of physeal violation of tunnel creation during ACL reconstruction in adolescent patients were 3.95% for the distal femur and 3.65% for the proximal tibia. Moreover, femoral tunnels were located more peripherally on the growth plate than were tibial tunnels, in both the anteroposterior and mediolateral directions.

LEVEL OF EVIDENCE: Level IV, case series.