Ewing sarcoma: right acetabulum
Following the MRI, the patient underwent an ultrasound guided biopsy of the right hip. The resulting specimens demonstrated an Ewing's sarcoma. The patient was referred to the oncologists for chemotherapy and to the gynecologists for a salpingo-oophrectomy for ovarian cryopreservation.
The patient underwent 2 different regimens of chemotherapy and has been referred to the orthopedic surgical team for surgical management of the residual disease.
The differential for a limping child is broad. Many cases are due to self limiting conditions such as transient synovitis. However more serious conditions causing a limp include infective conditions such as septic arthritis and osteomyelitis. In this age group slipped upper femoral epiphysis is also possible. Finally malignant conditions such as Ewings, whilst being rare, should be considered in any differential.
Regardless of the underlying condition, the limping child requires a thorough investigation and work-up.