What is Ankle Impingement? 

Ankle impingement occurs when either soft or bony tissues are compressed within the ankle joint at the extreme end of a motion, such as pointing the foot sharply downward. It typically affects people who experience forces through their ankle at these "end-range" positions, such as dancers, gymnasts, or people performing kicking activities. Additionally, people who perform repetitive tasks that involve squatting or stair-climbing are susceptible to this condition.

Anterior ankle impingement involves pain on the front side of your ankle. Inflammation and swelling occur due to repetitive stresses at end-range positions of the ankle, such as when one jumps, squats, or descends stairs. These may eventually lead to development of bone spurs (a bony overgrowth) in the ankle joint space. An additional cause of anterior ankle impingement is ankle instability. Ankle instability is a looseness of the ankle joint that develops after repeated ankle sprains, causing damage to ligaments in the ankle. This damage can cause the ligaments to become scarred and take up more joint space. Tissue in the joint space is then compressed, causing pain during activities that require ankle dorsiflexion (stretching your toes up toward your shin). Examples of these activities include squatting, jumping, and stair-climbing.

Posterior ankle impingement involves pain on the back side of your ankle, especially during activities that involve pointing your toes. The pain is caused by compression of soft or bony tissue between the shin bone (tibia) and the heel bone (calcaneus). Some people have a small extra bone in the back of their ankle called the Os Trigonum. This little bone can lead to posterior impingement because of compression between the shin bone and the heel bone, when the foot is pointed. Additionally, large amounts of force on the ankle occasionally may cause small pieces to break off the ankle bone, which can also become compressed when the ankle moves into "end-range plantar flexion" (moving the foot or toes downward toward the sole of the foot). Compression of tissue causes inflammation and swelling that leads to pain.

Signs and Symptoms

With anterior ankle impingement, you may experience:

• Pain on the front and/or outside of the ankle joint
• A feeling of ankle instability
• Decreased ankle range of motion when stretching your toes up toward your shin
• Pain at the end-range of stretching your toes toward your shin
• Tenderness at the front of the ankle when touched

With posterior ankle impingement, you may experience:

• Pain on the back of your ankle, especially during activities that involve pointing your toes
• Decreased range of motion when pointing your toes
• Tenderness on the back of the ankle when touched

How Is It Diagnosed?

Your physical therapist will perform a physical examination to evaluate your ankle strength, range of motion, sensation, and structural stability as well as your balance. Your physical therapist also will perform special tests, such as gently moving your ankle to see if it causes symptoms.

To provide a definitive diagnosis, your therapist may collaborate with an orthopedist or other health care provider. The most accurate method to diagnose ankle impingement is by X-ray or magnetic resonance imaging (MRI), which can be ordered by the orthopedist.