The longitudinal epiphyseal bracket: implications for surgical correction.

Surgical approaches to the correction of deformities in the skeletally immature hand or foot require adequate comprehension of the specific and changing chondro-osseous anatomy of each lesion. Detailed macroscopic and microscopic examination of an abnormal metatarsal showed a trapezoid-shaped diaphyseal/metaphyseal osseous unit that was longitudinally bracketed by a functioning physis and epiphysis along the lateral side. Only the medial side of the diaphysis had a normal periosteum. The arcuate physis extended from the medial, proximal side toward and along the lateral side and then back to the medial side distally. The epiphyseal ossification center was a composite of initially separate proximal and distal secondary centers that had a extended toward each other within the laterally placed epiphyseal cartilage. We have termed this deformity a "longitudinal epiphyseal bracket." We suggest that in the skeletally immature patient, opening wedge chondro-osteotomy should not routinely be accompanied by interposed bone graft extending to either the split ossification center or the physeal cartilage. Such a procedure may induce a partial surgical epiphyseodesis with subsequent progressive recurrence of the angular deformity or cessation of longitudinal growth. Instead, based on our anatomical findings, and preliminary surgical cases, we recommend osteotomy accompanied by fat interposition comparable to the Langenskiöld procedure for traumatic epiphyseodesis.