Achilles tendon ossification: pathology, imaging and aetiology

BACKGROUND: We report a patient with ossification of the Achilles tendon, presenting plain radiographs, ultrasound, power doppler, computed tomography and magnetic resonance findings. The majority of the tendon was ossified, and there was adjacent soft tissue oedema. The appearance of peritendinous oedema associated with ossification has not, to our knowledge, been reported in the literature, and could account for hindfoot pain in cases of tendon ossification. METHOD: A review of 44 articles on aetiology, histology and imaging was performed. RESULTS: Trauma, either accidental or from surgery, rather than tendinopathy is the likely aetiological factor. CONCLUSION: The Achilles tendon usually responds to an insult with the development of mature bone, not dystrophic calcification, with no evidence of inflammatory or degenerative changes.