Osteotomy of the Distal Fibula for Correction of Posttraumatic Malunion

Objective Restoration of anatomic alignment of the lateral malleolus to delay or prevent development of posttraumatic osteoarthritis of the ankle joint. Indications Posttraumatic malunion of the distal fibula with shortening, often combined with external rotation and abduction of the lateral malleolus. Osteoarthritic changes may be absent, mild or moderate. Contraindications Severe, preexisting osteoarthritis of the ankle. Presence of a remote lateral pilon fracture with articular depression. Poor soft tissue conditions after infection or sympathetic reflex dystrophy. Surgical Technique Lateral approach respecting former incisions or wounds, if at all possible. Osteotomy of the fibula (horizontal, oblique or Z-shaped), resection of scar tissue, osteophytes and bony fragments in the fibular notch and freeing of the distal part of the fibula. Correction of any obstacle around the medial malleolus if indicated. Correction of length, rotation and abduction of the lateral malleolus, and fixation with a reconstruction or LC-DC plate. Fixation of the fibula in the fibular notch with two Kirschner wires. Results After a follow-up of 3.9 years, all eight patients were satisfied. In five of six patients, there was only a slight progression of arthritic changes radiologically already present before osteotomy. Two patients without any arthritic changes before the osteotomy did not develo such changes thereafter. Our results, confirmed by previous reports, indicate that the most important factor determining the final outcome is the presence of degenerative changes at the time of osteotomy. Lengthening of the fibula slowed down or even stopped progression of arthritis.