Cadaveric Study on the Anterolateral Ligament of Knee: A Clinical Perspective

Background: The original discovery of an extra-articular ligamentous structure on the anterolateral aspect of the knee, now called the “Anterolateral ligament (ALL)” is credited to Dr Paul Segond. The ALL plays a key role in maintaining the rotational stability of tibia, hencea deeper comprehension of morphology of the ALL is necessary. Objective:To study the qualitative and quantitative characteristics of the ALL. Materials and methods: The study was conducted on 44 embalmed human cadaveric knees (34 male and 10 female), mean age 78.1 years.The various dimensions of the ALL (length, width, thickness) were measured using Verniercaliper, and its relations with surrounding structures were noted. Results: The mean length of the ALL in extension was 34.91±5.39mm and 39.15±5.46mm at 900 flexion, indicating stretching of the ligament during mid-flexion. The mean width of the ALL at femoral origin measured 8.33±2.74mm, at joint line 9.50±3.06mm and distal flaring at tibial insertion was clearly visible with mean width of 10.45±2.63mm. The ALL thickness at the joint line after separating it from lateral meniscus was 5.37±0.91mm. The lateral tibial recess was 7.32±1.72mm. The average distance between the centre of tibial ALL insertion to Gerdy's tubercle was 19.33±3.35mm and to the tip of the fibular head was 21.03 ± 5.78mm. There were no significant sex differences in any of the comparison. Conclusion: This study clarifies the long-standing enigma surrounding the existence of a ligamentous structure, connecting femur with the anterolateral aspect of proximal tibia.