Ankle impingement syndrome

Ankle impingement syndrome, also known as ankle impingement or ankle conflict, is a painful compression of the ankle joint tissues during certain extreme movements. It is not a single entity but a group of conditions distinguished by the location of the impingement: anterior impingement, anterolateral impingement and posterior impingement.

These syndromes occur when soft tissues — joint capsule, ligaments, synovial membrane — or, more rarely, bony structures become trapped between the tibia and the talus during movement, causing local inflammation followed by reproducible mechanical pain.

The clinical descriptions of these impingements are detailed extensively in the recommendations of the American Orthopaedic Foot & Ankle Society and in the biomechanical data published by INSERM.

The ankle is a complex joint involving the lower end of the tibia, the fibula (lateral malleolus) and the talus. Its stability and mobility depend on a set of capsuloligamentous structures — the joint capsule, the collateral ligaments and the synovial membrane — which line the tibiotalar joint space and normally adapt to the full range of dorsiflexion and plantar flexion.

Impingement syndrome occurs when these soft tissues, or more rarely a bony structure, abut against the opposite side of the joint during an extreme movement, causing repeated compression followed by a local inflammatory reaction. The location of this impingement allows three main forms to be distinguished.

Anterior impingement syndrome

The impingement is located at the front of the ankle, in the anterior tibiotalar space, during dorsiflexion movements. Repeated microtrauma in this area leads to capsular thickening, synovitis and, eventually, the formation of osteophytes (bone spurs) at the anterior tibiotalar junction — a picture sometimes called “footballer’s ankle”.

Anterolateral impingement syndrome

The impingement is located on the anterolateral aspect of the ankle. It most often follows a poorly healed lateral sprain: fibrous scar tissue persists and becomes trapped between the talus and the lateral malleolus during ankle movements.

Posterior impingement syndrome

The impingement is located at the back of the ankle, during maximal plantar flexion (pointing the foot). It involves compression between the tibia and the posterior part of the talus, sometimes promoted by the presence of an accessory bone, the os trigonum.

Impingement syndromes are a common cause of chronic ankle pain, particularly in athletes. They most often occur after repeated sprains, chronic ankle instability or trauma in extreme flexion.

The sports most affected are football, running, dance, trail running and, more broadly, pivoting sports.

Ankle impingement syndromes most often result from repeated microtrauma or from a poorly healed sprain. The mechanisms involved differ depending on the location of the impingement.

Anterior impingement

It follows repeated microtrauma in dorsiflexion, leading to capsular thickening, synovitis and then osteophyte formation.

Anterolateral impingement

It is very often secondary to a poorly healed lateral sprain, leaving scar tissue trapped between the talus and the lateral malleolus.

Posterior impingement

It occurs during maximal plantar flexion and particularly affects dancers, footballers and runners; it may be promoted by the presence of an os trigonum.

Risk factors

The main risk factors identified are repeated ankle sprains, chronic ankle instability and trauma in extreme flexion. Practising sports that involve changes of direction, landing from jumps or pivoting movements (football, running, dance, trail running, pivoting sports) also increases the risk.

Ankle impingement syndromes present as mechanical pain, triggered by certain extreme ankle movements, whose location varies according to the type of impingement.

In anterior impingement syndrome, pain is felt at the front of the ankle and triggered by dorsiflexion — for example when running downhill, landing from a jump or during a deep squat.

In anterolateral impingement syndrome, pain is located on the anterolateral aspect of the ankle. It typically appears following a lateral sprain and is a common cause of chronic pain persisting after the initial injury.

In posterior impingement syndrome, pain is located at the back of the ankle and occurs during maximal plantar flexion (pointing the foot), particularly in dancers, footballers and runners.

Surgery is rarely necessary and is only considered in cases that do not respond to well-conducted conservative management. It usually involves removing the impinging tissue (scar tissue, hypertrophic synovium, osteophytes) and freeing the joint space, most often arthroscopically.

Recovery time varies depending on how chronic the impingement is, generally between 6 weeks and 4 months. A return to sport is possible by modifying the movements that trigger the pain.

Preventing ankle impingement relies above all on complete rehabilitation after any ankle sprain, including regular proprioceptive work and maintaining good joint mobility.

Muscle strengthening and an appropriate sporting progression, avoiding sudden increases in load or intensity, complete this prevention.