Intralesional Ethibloc injections in primary aneurysmal bone cysts: an efficient and safe treatment

Ethibloc is a fibrogenic and thrombogenic agent recently proposed for the treatment of bone cysts. The purpose of this study is to report the results of direct Ethibloc injection in primary aneurysmal bone cyst (ABC) in children. Seventeen patients, aged from 2 to 18 years (mean 8 years), were treated with either a single injection (14 patients) or supplementary injections (3 patients) of Ethibloc. The histological diagnosis was assessed following surgical biopsy and was retrospectively reviewed. The mean follow-up was 5 years (range 18 months to 11 years). At 5 year follow-up, 14 of 17 patients demonstrated complete healing manifest by increased cortical and septal thickening. Surgical excision was required in three patients, in two of whom the ABC increased rapidly in size despite the injection, and in one of whom the healing was incomplete. We observed inflammatory reactions in 16 of 17 patients with local pain and fever. Three patients developed a small cutaneous fistula which resolved spontaneously in a few weeks. No major complications such as deep infection, pulmonary embolism, epiphyseal necrosis or malignant degeneration were observed. Percutaneous direct Ethibloc injection is a safe, efficient and noninvasive treatment for ABC. The authors highlight the frequent local reactions.