Impingement Syndromes of the Ankle
Impingement is derived from the Latin verb impingere, meaning “to force against” where an anatomic structure becomes entrapped causing pain, bony and soft tissue injury, decreased range of motion, and dysfunction. When impingement occurs, one bone repetitively strikes another, which over time can stimulate the deep layer of the periosteum to form osteophytes that further exacerbate the impingement and alter the normal mechanics of the ankle joint. Osseous or bony impingement most commonly occurs following spur formation along the anterior margin of the distal tibia and talus or as a result of a prominent posterolateral talar process-the os trigonum (OT). Soft tissue impingement usually results from scarring and fibrosis associated with synovial, capsular, or ligamentous injury and most often occurs in the anterolateral gutter, the medial ankle, or in the region of the syndesmosis. Conservative treatment such as activity modification and retraining should be aimed at breaking this repetitive cycle in order to decrease the inflammation and provide relief. However, the sporting limitations are often limiting, and if conservative management fails, surgery is usually indicated.