Aneurysmal bone cyst of the calcaneus: a case report and review of the literature

Aneurysmal bone cysts (ABCs) are locally destructive, blood-filled benign bone lesions traditionally regarded as reactive rather than true neoplastic lesions. ABCs typically affect the proximal humerus, distal femur, proximal tibia, and spine. Involvement of the calcaneus is rare, representing approximately 1.6% of reported cases. A PubMed search identified nine publications describing 22 cases of calcaneal ABCs. Here, we report a rare case of ABC arising in the calcaneus and review the relevant literature. A 17-year-old Japanese male with no relevant medical history presented with left calcaneal pain and gait disturbance. The patient underwent curettage with phenol–ethanol ablation and artificial bone packing (β-tricalcium phosphate [β-TCP], AFFINOS®, KURARAY Co., Tokyo, Japan). No local tumor recurrence was observed at the 36-month follow-up. This case highlights a rare ABC arising in the left calcaneus of a 17-year-old Japanese male, with no recurrence after 36 months. Although adjuvant therapy was performed in this case, additional cases are required to clarify its necessity in the management of calcaneal ABC.