Ankle impingement occurs when a bony growth at either the front or back of the ankle bone where it meets the shin bone restricts normal ankle range of motion.
Ankle impingement can be anterior affecting the front of the ankle or posterior impingement affecting the back of the ankle depending on where the bony growth occurs. Impingement can often occur following an ankle sprain which fails to heal properly.
Symptoms of anterior impingement
Symptoms include pain felt at the front or side of the ankle which does not go after an ankle sprain heals. The ankle may seem weak and one giveaway sign is reproducing pain by forcing or passively moving the ankle into dorsi flexion or pointing the foot upwards to stretch the muscles at the back of the leg.
Symptoms of posterior Impingement
Pain is usually felt at the back of the ankle. There will be tenderness behind the bottom tip of the fibulabone. Pain will most likely be worse at the end of the movement when the foot is pointed down into plantarflexion with the foot pointing downwards. Going up onto tip toes may be painful. An X-ray can show up any bony spurs on the talus (heel bone) and end of the tibia (shin bone).
Tissues in the ankle joint can become trapped between bones in the ankle. This is known as impingement and occurs when the ankle is bent fully up or down. Posterior impingement in the back of the ankle is more common in ballet dancers and can be due to a bony protrusion at the back of the ankle.
Anterior impingement (at the front of the ankle) can occur from a bad or repeated ankle sprain as the ligaments thicken and get pinched between the bones (tibia and talus bone). As the torn or ruptured ligament heals, the body forms too much scar tissue along the front and round the side of the ankle joint creating a meniscoid lesion.
A doctor may prescribe NSAID's (non stroidal anti inflammatory medication). If conservative treatment does not work then surgery may be considered.