Giant cell tumor (GCT) is a common benign aggressive tumor that mostly occurs in the proximal tibia, distal radius, and distal femur but is rarely seen in the distal region of the humerus. It originally presents between the ages of 30 and 50 with suddenly occurring pain. Treatment is generally curettage adjuvant treatment if necessary and reconstruction if required. In our case report, we present the clinical and radiological findings, diagnosis, and management of a 33-year-old female patient with a giant cell tumor (GCT) accompanied by a secondary aneurysmal bone cyst (ABC) in the left distal humerus, where the patient experienced pain for many years without significant history of trauma. Upon clinical examination, the patient displayed tenderness over the medial side of the elbow but no noted swelling, redness, or hotness. She had a painless full range of motion, with an intact distal neurovascular examination. Imaging concluded GCT with secondary ABC. A biopsy confirmed the diagnosis, ruling out metastatic lesions. The patient underwent surgical intervention, with plate fixation, which yielded excellent outcomes.

BACKGROUND: Giant cell tumour of bone (GCT) is a common benign primary bone tumour, seen commonly in the distal Femur, proximal Tibia and distal Radius. Very few cases of GCT are reported in distal humerus. We report an unusual presentation of recurrent Giant cell tumour in a 25 year old male in the medial condyle and epicondyle of left Humerus.
METHODS: Patient presented elsewhere with lytic lesion of left elbow three years ago. As it is an uncommon site for tumors, it was misdiagnosed as tuberculous osteomyelitis and was inadequately curetted. Patient presented to us with recurrence of tumor one year after the primary surgery. We did en-bloc resection of the tumour, with judicious removal of partial trochlea. Though reconstruction was planned, it was found to be not necessary as the elbow was stable per-operatively. Patient regained near normal movements of the elbow with no instability. His Mayo Elbow Performance score improved from 30 to 85. There is no recurrence or metastasis of the tumor in the two-year follow-up.
CONCLUSIONS: Though bone tumors are rare in distal Humerus, biopsy is needed to confirm the diagnosis of any lytic lesion in this region for proper management.