Anterior Ankle Impingement
Edited by Marcus Coe MD
Background and Clinical Presentation
Anterior ankle impingement is one of the most common cause of pain in the front of the ankle joint (Figure 1). In this case, “impingement” describes pinching at the front (anterior portion) of the ankle joint while walking or leaning forward (dorsiflexion). Often this impingement is due to bone spurs that form at the front of the ankle joint on the tibia (upper bone of the ankle joint) and/or the talus (lower bone of the ankle joint). Bone spur formation can be a result of frequent forceful dorsiflexion (bending the ankle upwards or leaning over the ankle with the heel on the ground). Soccer or dancing are activities that can cause bone spurs, but often the source of spurs is unknown. Frequent ankle sprains can cause bone spurs or they can be a result of early arthritis. Squatting, bending, and going upstairs or inclines can cause pinching of the bone spurs together, causing pain. Bone spurs typically appear as a “beak” or “awning” extending from the front of the ankle joint. These spurs are seen on lateral x-rays of the ankle and serve to physically block upward ankle motion (Figure 2). Sometimes inflamed soft tissue as opposed to bone spurs can cause anterior ankle impingement. As inflamed, enlarged soft tissue comes in contact with dorsiflexion, it can cause pain.
Figure 1: Location of Pain in Anterior Ankle Impingement
Figure 2: Impingement “Jamming” in the Front (Anterior) Ankle
In early anterior ankle impingement, MRI may demonstrate inflammation or fluid accumulation in the front of the ankle joint. Later, the bone spurs at the front of the ankle can be seen on an ankle x-ray taken from the side (lateral view). The size of the bone spur can vary from very small to quite large (Figure 3). X-rays may also demonstrate mild, moderate, or even severe ankle arthritis.
Figure 3: Anterior Ankle Bone Spurs
Early on, treatment can focus on stretching, physical therapy, over-the-counter medications, shoe inserts, and injections. Some potentially effective non-operative treatments are:
- Use of a Slightly Elevated Heel: Using a shoe with 1-1.5” heel (or adding a heel lift inside the shoe) means that the foot does not need to come up as far in the course of normal walking. Therefore, less impingement occurs and patients will tend to be less symptomatic.
- Activity Modification: If appropriate, avoiding or limiting activities (i.e. certain sporting activities or walking uphill) that cause ankle jamming will tend to cause the symptoms to improve.
- Anti-inflammatory medication (NSAIDs): The use of anti-inflammatory medication (assuming no contra-indications) can be helpful if persistent symptoms are present.
- An occasional injection of corticosteroid into the ankle joint may be helpful, particularly if there is some underlying ankle arthritis present.
- If frequent sprains are a source of bone spur formation, exercises to stabilize the ankle and avoid sprains can be useful.
The focus of operative treatment is to remove the impinging bone spurs or inflamed soft tissue at the front of the ankle and increase ankle motion, thereby decreasing the pressure created in the front of the joint during walking or other activities. This can be done arthroscopically, through a camera with small instruments inserted into the joint, or with an incision and open removal of the bone spurs. Bone spur removal is sometimes coupled with procedures to stabilize stretched out lateral ankle ligaments or lengthen tight tendons in the back of the ankle or the calf.
Edited on November 17, 2020