Larsen syndrome is characterized by anomalies present at birth. These include a flat face, hypertelorism, cleft palate, cleft uvula, and laxity of joints with dislocations. In addition, there are central nervous system abnormalities, congenital heart defects, and neurological impairment due to cord compression. Not all anomalies may be present, and the condition is frequently under diagnosed. Our patient presented with right leg pain and limitation of motion of the right hip. The diagnosis of Larsen syndrome was not known. A radionuclide bone scan was performed to rule out an acute injury. The examination demonstrated extraosseous accumulation of tracer in the right thigh. An MRI scan showed edema involving the entire right sartorius muscle. This was secondary to repeated dislocations of the hip because of Larsen syndrome, which was established with genetic consultation.