A giant solitary osteochondroma of the fibular neck with nerve compression in a 35-year-old male: a case report from Afghanistan.

Introduction: Osteochondromas are the most common developmental bone tumors, usually presenting in childhood or adolescence as slow-growing, painless swellings. They typically arise from the metaphyseal regions of long bones and are composed of mature bone capped by hyaline cartilage. The most frequent sites are around the knee, particularly the distal femur and proximal tibia. Growth after skeletal maturity is rare and raises concern for malignant transformation. Case Presentation: We report a 35-year-old male who presented with a progressively enlarging swelling in the right proximal leg, accompanied by weakness in foot dorsiflexion. The patient first noticed the mass 6 years earlier, with accelerated growth over the last 7 months. Radiographs demonstrated a giant pedunculated, cauliflower-shaped mass arising from the fibular neck. Surgical excision was performed, yielding a specimen measuring 15 × 13 × 8.5 cm. Histopathological evaluation confirmed benign osteochondroma. The patient's neurological function improved postoperatively, and no recurrence was observed during 10 months of follow-up. Discussion: Osteochondromas generally cease growth following epiphyseal closure; hence, substantial enlargement in adulthood is unusual. Fibular neck involvement is rare, and compression of adjacent neurovascular structures occurs infrequently. Tumor size and anatomical location are the main predictors of complications. The current case represents one of the largest solitary osteochondromas of the fibula reported in the literature, with clinically superficial peroneal nerve compression. Conclusion: This case underscores the importance of considering osteochondroma in adults with enlarging bony masses and neurological deficits. Timely diagnosis and surgical intervention can achieve excellent outcomes, even in giant lesions.