The management of nonunions following high tibial osteotomies.

Nonunion is an uncommon complication of high tibial osteotomy. Reported techniques of treating such a complication include resection of the pseudarthrosis and cast immobilization with risk of joint stiffness and loss of alignment. The special AO/ASIF threaded external fixator with double clamps was used to treat three patients with nonunions following high tibial osteotomy for medial compartment osteoarthritis. The pseudarthrosis was not resected in any instance. All were allowed full unrestricted joint motion postoperation. Rapid healing of the osteotomy ensued. The external fixator achieved excellent stability and rapid union while maintaining joint motion.