The treatment of nonunion of proximal tibial osteotomy with internal fixation.

Nonunion of proximal tibial osteotomy is a rare occurrence. Treatment goals should emphasize preservation of proximal tibial bone stock in view of possible subsequent total knee arthroplasty (TKA). Previous reports, in mostly smaller series, have emphasized the use of external fixation in the management of this problem. There have been no previous reports regarding the use of internal fixation in the treatment of nonunion occurring after tibial osteotomy performed proximal to the tibial tubercle. In this report, the results of internal fixation in the treatment of six cases of nonunion after proximal tibial osteotomy are analyzed with regard to functional and roentgenographic results. Healing of the nonunion was obtained in all six patients. Realignment of angulatory deformities was uniformly achieved. Achievement of union and correction of axial malalignment, in addition to creating an improved substrate for later TKA, provided other objectives as well. Elimination of pain and instability at the nonunion site allowed these patients to derive some of the intended benefits from the original osteotomy.