Anterolateral Meniscofemoral Ligament Associated with Ring-shaped Lateral Meniscus and Congenital Absence of Anterior Cruciate Ligament, Managed with Ligament Reconstruction.

A 24 year old otherwise healthy male presented with a chief complaint of giving way in the left knee. MRI reported complete anterior cruciate ligament (ACL) tearing. Arthroscopy showed ACL agenesis, ring-shaped lateral meniscus, and an anomalous thick band extending from the anterior horn of the lateral meniscus to the intercondylar notch of the lateral femoral condyle, which is known as the anterolateral meniscofemoral ligament (MFL). The MFL was attached to the anatomic site of anteromedial bundle of ACL. ACL reconstruction surgery was performed using central 1/3 bone tendon bone graft. Practitioners should be aware that ACL reconstruction in lateral meniscofemoral ligament with associated ACL agenesis is a treatment option in which the preservation of MFL, as the stabilizer of anterior horn of lateral meniscus, should be considered during ACL reconstruction.