What ligaments are there around the ankle?
The ankle joint is the junction between the bones that make up your lower leg (tibia and fibula) and a bone in the foot known as the talus. The talus is held to the tibia and fibula by strong bands of tissue called ligaments.
Each ligament is made up of strong fibres made from a material called collagen.
The ligament on the outside of the ankle (lateral ligament) is made up of three separate bands: one at the front (anterior talo-fibular ligament or ATFL), one in the middle (calcaneo-fibular ligament or CFL) and one at the back
(posterior talo-fibular ligament or PTFL). The front band (ATFL) is the part that is usually injured in an ankle sprain, and occasionally the middle band (CFL) is also affected in more severe injuries. The ligament on the inside
of the ankle (medial or deltoid ligament) is made up of two layers with the deepest part being more important to providing stability. This ligament is mainly torn in association with severe fractures of the ankle bones.
How do the ligaments get injured?
Most ankle ligament injuries happen when the foot twists inwards (inversion) beyond its normal limit. As the force of your body weight is transferred to the ankle, this can tear some or all of the fibres that make up the lateral
ligaments. Occasionally small pieces of bone may be torn off with the ligaments (avulsion fracture).
In a few cases, a twisting force on the ankle may cause other damage: the bones around the ankle may be broken; part of the surface inside the ankle joint may become chipped; ligaments connecting other bones in the foot may be
sprained or torn; or the tendons around the ankle may be damaged.
