再発性第一中足骨巨大細胞腫に対する血管柄付き中足骨移植術による再建：長期機能予後

Giant cell tumor (GCT) (osteoclastoma) is a locally aggressive bone neoplasm with an incidence of 3-8% of all bone tumors, rarely seen (1-2%) in smaller bones of the feet. It is located in the epiphysis-metaphysis of long bones. If inadequately treated, they have a high recurrence rate.

It is a rare case report of recurrent GCT of the first metatarsal in a 28-year-old female who was previously treated with curettage and bone grafting. After confirmation of the lesion with fine needle aspiration cytology, she underwent en bloc resection of the first metatarsal with vascularized transfer of the second metatarsal to the first metatarsal.

She was initially started with partial weight-bearing walking with elbow crutches, and full weight-bearing was started at 4 months. She was followed for over 12 years without recurrence. Functional outcomes assessed by the American Orthopedic Foot and Ankle Society scoring system showed significant improvement, with midfoot and hallux metatarsophalangeal-interphalangeal scores increasing from 22 to 91 and 30 to 87, respectively.

GCTs of the small bones of the foot, though rare, exhibit aggressive behavior and high recurrence. En bloc resection with vascularized second metatarsal transfer offers a reliable reconstructive option with excellent long-term functional outcomes and minimal donor site morbidity if it involves the entire metatarsal. This technique is a viable limb-salvage alternative to amputation in recurrent GCT of the first metatarsal.