Purpose of the study: Echinococcosis is an anthropozoonosis with a predominantly muscular, more rarely osteoarticular, localisation. The purpose of this work was to describe the conditions of discovery, the diagnostic management, the serology and pathology findings, and the results of surgical treatment as well as potential complications.

Material and methods: We collected over a 16-year period, 14 cysts in eight women and six men. Mean age was 39 years (range 17–75) and delay to consultation was 36 months. The patients had an ultrasound (all 14 cases), computed tomography (n=7), MRI (n=7), hydatid serology (n=9) and pathology examination (n=10). All patients were treated surgically (7 complete resection); one patient was given associated medical treatment for a multiple localisation.

Results: Muscle hydatisosis occurred in all cases as a medium-sized tumour (mean 9 cm, range 5–16 cm) which was painful in half of the cases. One cyst was superinfected and one patient had a neurological complication. The most common site was the adductor compartment of the thigh (5 cases). Four patients had an associated visceral localization. At mean 4 years follow-up, one patient had a superinfection and two others recurrence at 7 and 10 months, with surgical revision and good outcome.

Discussion: The risk vascularisation of the thigh muscles explains these localisations. Ultrasound is a sensitive exploration which suggests the diagnosis in all cases. CT and MRI confirm the diagnosis and define the cyst relations. Pathology is needed for formal diagnosis. Total pericystectomy or wide resection is the best surgical technique, although not always readily achieved.

Conclusion: Muscle hydatidosis is rare. Treatment is surgical, different from the osteoarticular localisation, similar to the visceral foci. Recurrence is exceptional. Prevention remains the best treatment.