Cystic echinococcosis, also known as hydatid disease is a worldwide zoonosis, caused by the larval stage of the echinococcus granulosus which usually affects adults. the frequency of osseous involvement in hydatid disease is 0.5%–4%. bone hydatidosis must be suspected on clinical and radiographic features. ct and mri are the best imaging tools for diagnostic confirmation, assessment of local extension and post operative follow-up.results of surgical treatment of bone hydatidosis are not gratifying. an apparent radical removal doesn’t mainly avoid recurrence of the illness. medical treatment may frame surgery to reduce the risk of recurrence. primary muscular hydatidosis is rare, with only isolated cases being described in the literature. ultrasonography and mri are the tools of choice to confirm the diagnosis of muscular ce. total cystectomy removing the whole cyst and going INTO [Al-Fikr-Master].dbo.the adventitious healthy muscle cleavage plane is at the moment the gold standard technique as it avoids complications linked to the persistence of residual shell and recurrences.