Rare Case Of Ankle Pain In An Adolescent

HISTORY: A 10 year-old male presented to a pediatric sports medicine clinic with episodic right heel pain over 1.5 years. His condition was previously diagnosed as calcaneal apophysitis. At his sports medicine visit, he states at times the pain radiates from his medial to lateral malleolus and down to the heel, accompanied with difficulty bearing weight. During his last episode of pain one month prior to his visit at the clinic, medical records indicated his heel was erythematous, warm and tender with a temperature of 100.4F. PHYSICAL EXAMINATION: The patient was afebrile and the heel was non-erythematous. Negative calcaneal squeeze and heel bump and no pain with weight bearing. Notably, his calves were not very tight. DIFFERENTIAL DIAGNOSIS: 1) Osteomyelitis 2) Stress fracture 3) Rheumatological processes 4) Malignancy 5) Calcaneal apophysitis TESTS AND RESULTS: Prior to this visit, the patient had a non-diagnostic bedside ED ultrasound with normal CRP, mild microcytosis without anemia, mild leukocytosis and hypovitaminosis D. At his sports visit, calcaneus x-rays demonstrated irregularity of the lateral portion of the calcaneus and subtle irregularity of mineralization with areas of lucency. Patient was then referred for MRI on which two regions of soft tissue extension through the medial and lateral cortex of the calcaneus and a focal area of more confluent enhancement adjacent to calcaneal cuboid joint space were observed. Patient was then referred for an IR guided needle biopsy. FINAL/WORKING DIAGNOSIS: Biopsy resulted in small round blue cell tumor. Final diagnosis was Ewing sarcoma of the right calcaneus, clinical stage IA, localized. TREATMENT AND OUTCOMES: 1) Patient was started on chemotherapy 2) Patient was recommended to have BKA but the family elected to undergo radiation therapy without amputation. Five years post chemotherapy and radiation treatment, he remains in remission and is doing well.