against plantar flexion and internal rotation of the foot.
12,14,15
The CFL forms a 133° angle with the fibula and a 104° angle
with the ATFL. The CFL is relaxed in plantar flexion and taut
in dorsiflexion and thus stabilizes the ankle and prevents talar
tilt as the ankle moves from neutral into dorsiflexion.
12,14,15
The most common mechanism of injury in lateral ankle
sprains occurs with forced plantar flexion and inversion of
the ankle as the body’s center of gravity rolls over the ankle.
The ATFL followed by the CFL are the most commonly
injured ligaments. Many investigators have confirmed this in
biomechanical and clinical studies. Attarian and colleagues
17
found in a cadaveric study that the maximum load to failure
for the CFL was two to three-and-a-half times greater than
the ATFL.
16
Brostrom
17
surgically explored 105 sprained
ankles and found that two-thirds of the ankles had an ATFL
tear, while a quarter of the ankles had a combined ATFL and
CFL rupture