Presentation
Two-month history of insidious right groin and abdominal pain radiating into the right hip and knee. The pain is unaided by simple analgesia. O/E - The range of motion in the right hip is reduced globally. Antalgic gait. Elevated ESR (100) and CRP.
Patient Data
Permeative lytic lesion in the right superior pubic ramus.
Infiltrative lesion in right acetabulum with bone extension into right superior pubic ramus. There is a large soft tissue mass that extends medially into obturator internus and displaces the pelvic contents to the left. There is infiltration surrounding the iliac vessels and extending into the posterior iliopsoas muscle. There is also infiltration extending towards the sciatic notch.
Case Discussion
Following the MRI, the patient underwent an ultrasound guided-biopsy of the right hip. The resulting specimens demonstrated an Ewing sarcoma.
The patient was referred to the oncologists for chemotherapy and to the gynecologists for a salpingo-oophorectomy 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.
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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 Ewing sarcoma, whilst being rare, should be considered in any differential.
Regardless of the underlying condition, the limping child requires a thorough investigation and work-up.