[Scapulohumeral hydatidosis: a new case in Tunisia].

Osseous hydatidosis is reported in only 0.5-2.5% of the cases. The scapulohumeral localization is extremely rare. A 39-year-old woman, born in a rural area of Tunisia, presented swelling and tenderness of the left shoulder with limited motion 7 days after a minor trauma. Plain radiographs, CT and MRI showed osteolytic scapulohumeral lesions, cortical rupture and multiple cysts in the muscles, which were suggestive of hydatidosis. Indirect haemagglutination test using hydatid antigen was positive (1/280). The patient refused radical surgery and underwent resection of axillary cysts. Albendazole was given in the recommended dose but was stopped immediately due to hepatic toxicity. Scapulohumeral hydatidosis is extremely rare, often invasive and behaves like a locally malignant bone tumour. Its treatment is also difficult.