Residual bone cysts after correction of severe foot deformities with the Ilizarov technique

Fourteen patients with severe foot deformity treated by application of the Ilizarov device were evaluated for residual bone changes in the foot. Cyst formation was noted in all patients, most commonly in the base of the fifth metatarsal. These cysts did not develop in the area of bone penetrated by the wires. In an average follow-up of 3.4 years after device removal, the cysts did not resolve. Histologic examination of one resected cyst demonstrated an empty lacuna with no cell lining, as seen in the "cysts" associated with osteoarthrosis.