Locked intramedullary nailing. Its application to femoral and tibial axial, rotational, lengthening, and shortening osteotomies.

Interlocking nailing is an alternative method of internal fixation following corrective osteotomies for malunions or after correction of leg length inequality. Of 13 osteotomies (six femoral, seven tibial) for angular or rotational malunion, all healed following dynamic locked nailing. Eleven were considered anatomic and two had mild residual deformity. One-stage femoral lengthening was performed in 17 patients. The preferred operative technique includes a long Z-shaped osteotomy, static interlocking nailing, primary cancellous bone grafts, and one or two supplemental screws at the osteotomy site to prevent shortening following dynamization. Thirteen complications developed following one-stage lengthening of the femur, which included significant loss of length in five patients, femoral nerve palsies in four patients, three deep infections, and one nonunion. Lengthening should not exceed 4.0 cm in the femur. The recommended technique of shortening osteotomy consists of resection of a cylindric segment of bone from the distal diaphyseal metaphyseal area. Shortening should not exceed 4.5 cm in the femur or 3.0 cm in the tibia. In ten patients who were shortened, all healed, but radiologic signs of union appeared very slowly in most cases.