Intra-Articular Osteochondroma in the Elbow: Diagnosis and Surgical Treatment in an 8-Year-Old Boy.

BACKGROUND Osteochondroma is the most common bone tumor and is a surface bone lesion that includes cortical and medullary bone with a hyaline cartilage cap. Benign osteochondroma is a common tumor in children that may be asymptomatic but can cause pain and limit joint movement when arising in a joint. This report describes the presentation, diagnosis, and management of an intra-articular osteochondroma of the right elbow joint in an 8-year-old boy. CASE REPORT An 8-year-old boy experienced persistent right elbow pain and limited motion, which were unresponsive to conservative measures. Examination revealed a firm swelling in the right cubital fossa. Radiographic and advanced imaging confirmed an osteochondroma originating from the capitellum and trochlea. Surgical exploration via a lateral approach and capsulotomy excised a lobulated intra-articular mass (5×2×1.5 cm). Histopathology showed a hyaline cartilage cap with typical chondrocytes and endochondral ossification, and normal fatty marrow and hematopoietic elements in the stroma. The procedure restored normal elbow function. This case is the first documented instance of an elbow joint intra-articular osteochondroma. CONCLUSIONS This report has highlighted the importance of surgical removal and histopathology in the diagnosis of this common bone lesion to exclude the differential diagnoses of intra-articular masses that include a foreign body, enchondroma, chondroblastoma, periosteal chondroma, chondromyxoid fibroma, or malignant chondrosarcoma.