Abstract
INTRODUCTION: The development of hydatid cysts in the muscle is rare, and it is even rarer in children. We report the case of a 9-year-old child treated in pediatric orthopedics department at the University Hospital of Marrakech for a hydatid cyst psoas muscle revealed by lameness. RESULT: The child was consulted for painless and afebrile lameness of the left hip evolving since 3 months. The clinical examination finds a mass of the left flank. Investigations based on the abdominal ultrasound in first intention showed a hydatid cyst depending on the left psoas muscle. Pelvic CT and abdominal MRI were able to confirm the diagnosis and allowed a better study of the cyst neighboring elements. The drainage of the cyst followed by pericystectomy after evacuation of the vesicles contained in the cyst was done as radical treatment. CONCLUSION: The hydatid cyst of the psoas is a rare entity in the child requiring a good radiological study of the cyst as well as its neighboring elements to propose the most adapted surgery.