Insertional Achilles tendinopathy (IAT) is the chronic degeneration of the Achilles tendon at its insertion at the midportion of the posterior aspect of the calcaneus. Hallmarks of this disease include ossification of the entheseal fibrocartilage leading to bone spurs and tendon tears with associated pain at the insertion site. IAT is a chronic degenerative condition in the absence of underlying inflammation and is commonly observed in active individuals as well as overweight females in their 40s and in individuals over age 60.¹ Since running can apply 4 to 6 times the force of body weight on the Achilles tendon, IAT has been noted to end careers for up to 5% of professional athletes.²

The changes within the Achilles insertion that result from this disease include a loss of parallel collagen fibers due to disorganization from fatty infiltration, intratendinous degeneration, and the proliferation of capillaries. Clinically, patients often present with pain at the prominent posterior heel bump and Achilles/gastrocnemius tightness. Pain is exacerbated by physical activity and after walking following a period of rest (ie, with the first steps in the morning). Radiographically, posterior calcaneus spurs will typically be observed on lateral hindfoot radiographs, although the spurs themselves are not the cause of the pain but rather a manifestation of the chronic tendon degeneration. More advanced imaging (magnetic resonance imaging or ultrasonography) may be necessary in cases where the clinician is uncertain whether the diagnosis is an IAT or a true Haglund deformity, the latter causing inflammation of the tendon in the absence of tendinopathy.

The first approach to treat IAT consists of physical therapy to stretch and eccentrically strengthen the tendon, with the addition of icing, open-back shoes, and a heel lift to mitigate the pain. Extracorporeal shock wave therapy, night splinting, open-back shoes, and platelet-rich plasma have also been described.²,⁸