Applied anatomy of anterolateral ligament in adults

Objective To explore the anatomical features of the anterolateral ligament (ALL) in Chinese population , and to provide anatomic basis for the diagnosis and treatment of anterolateral ligament injury. Methods A total of 19 adult knee joint specimens were specially selected by the Department of Anatomy of Shanxi Medical University. All the knee joint tissues from 11 males and 8 females (including 9 left knee joints and 10 right knee joints) were intact without damage, deformity and surgical trauma history. The anterior aspect of the knee joint was used as an operation center to find and observe the anatomical features of ALL, such as the starting and stopping points and traveling, etc. ALL and its adjacent structures were photographed and measured, and the research results were recorded for ualitative and quantitative description. Results In 19 cases of knee joint specimens, anterolateral ligament specimens were found in 17 cases. The lengths of ALL in the neutral 0°position and the flexion 60°with internal rotation 5°position were (34.72±6.35) mm and (39.53±6.80) mm. The widths of ALL at the femoral attachment、the tibial attachment and joint line were (7.75 ± 0.81) mm, (9.41 ± 1.19) mm and (6.79 ± 1.01) mm. The ALL as a whole was a wide flat shape from the posterior superior to the anterior lateral edge of the knee joint, with a thickness of (1.21±0.20) mm at the joint line. The tibial attachment was located above the midpoint of Gerdy's tubercle and the fibular head, and the vertical distance to the tibial cartilage margin was (11.62 ±1.32) mm. The distances from the tibial attachment to the Gerdy's tubercle and the fibular head were (19.95±4.63) mm, (19.47±3.65) mm. The distance from the Gerdy's tubercle to the fibular head was (33.82 ± 4.69) mm. Conclusions ALL is an independent non-equal length ligament structure located outside the anterior and posterior joint capsule of the knee joint. It starts from the posterior superior part of the lateral epicondyle and travels forward and downward. It connects with the lateral meniscus body and ends above the midpoint of the Gerdy's tubercle and the fibular head. ALL plays a certain role in maintaining the rotational stability of the knee joint . Key words: Knee joint; Anterolateral ligament; Lateral collateral ligament; Anatomy; Segond fracture