Anatomical review of the lateral collateral ligaments of the ankle: a cadaveric study.

Arrangements of the lateral collateral ligaments of the ankle are complex. Injuries to these ligaments can occur in the inverted planter flexed position of the ankle. Traditionally, the anterior talofibular ligament (ATFL) is the first ligament involved in such ankle injuries. We reviewed the anatomical arrangements of the lateral ankle. Twenty ankles from ten Caucasian cadavers were carefully dissected. Length and width of each ligament were measured in neutral, dorsiflexion and plantar flexion. The angle between the ATFL and other ligaments was also recorded. ATFL was present in 95% of ankles dissected. Five ankles showed two slip configuration of the ATFL. One ATFL was noted as being significantly thicker and another one was significantly narrow. Mean length of the ATFL in neutral was 15.5 mm (range 10-21 mm), which increased in plantar flexion to 18 mm (range 11-25 mm) and decreased slightly in dorsiflexion to 14.5 mm (range 10-19 mm). The calcaneofibular ligament was present in all dissections and had a mean measurement of 18.5 mm in neutral (range 14-23 mm) decreasing to 17 mm in planter flexion and 15.5 mm in dorsiflexion. Treating ligamentous ankle injuries can be very costly, thus creating a large economic burden to both patients and health institutions. Understanding the anatomical characteristics of the lateral collateral ligament complex of the ankle provides the basic foundation for understanding injuries and helps to clinically manage such injuries appropriately.