Total destruction of the fourth metacarpal bone by aneurysmal bone cyst: reconstruction with strut fibular graft--a case report.

Total destruction of the fourth metacarpal bone by aneurysmal bone cyst is presented. Despite the benign nature of the lesion on plain radiograms, magnetic resonance imaging (MRI) has revealed total destruction of metacarpal bone with shelling off the articular cartilages on both ends of the metacarpal. Both adjacent dorsal interosseous muscles were also involved with tumour. After removal of the metacarpal bone and third and fourth interossei, fibular bicortical strut graft was used for reconstruction. Arthrodesis was done both at the carpometacarpal and metacarpophalangeal (MCP) joints. The follow-up radiograms at one year revealed excellent incorporation of the graft with no evidence of local recurrence. A careful pre-operative work-up including MRI seems necessary even in lesions that look typically benign with intraosseous location on plain radiograms. This approach may prevent unpredicted morphologic picture during surgery, high recurrence rate and the number of operations.