Trauma Revealing a Tumour: A Case Report

A 25-year-old male patient presented to the emergency department with acute left knee pain and swelling after a fall. He had been experiencing left knee pain for several months. Examination revealed a swollen left knee held in a flexed position with limitation in range of motion. Plain radiographs performed showed a lytic lesion over the left lateral femoral condyle, and the patient was admitted for computed tomography (CT) and magnetic resonance imaging (MRI) scans. An open biopsy was performed, and immunohistochemical staining of the tumour cells was positive for H3G34W, confirming the diagnosis of giant-cell tumour of bone (GCTB). The patient subsequently underwent left distal femur GCTB curettage, bone grafting, and internal fixation. This case highlights how incidental trauma can reveal a previously undiagnosed bone tumour, underscoring the need for clinicians to maintain a high index of suspicion when evaluating patients.