Medial Open Wedge High Tibial Osteotomy for Varus Malunited Tibial Plateau Fractures.

ABSTRACT

PURPOSE: To analyze radiologic and functional outcomes of varus malunited tibial plateau fractures managed with medial open wedge high tibial osteotomy (MOHTO). METHODS: Eighteen patients with symptomatic varus malunited tibial plateau fractures with less than stage II arthritic changes managed from July 2009 to October 2013 were included. Patients with complex intra-articular step malunions and severe arthritic changes (stage III and IV) were excluded. Initially, diagnostic arthroscopy was performed followed by MOHTO stabilized with locking plate and tricortical autograft (n = 11, 61%) or a Puddu plate and allograft (n = 7, 39%). Patients were evaluated radiologically for union, medial proximal tibial angle, and tibial slope angle, and functional assessment was performed with a knee outcome survey based on activities of daily living. RESULTS: The mean follow-up duration was 41.7 ± 12.1 months (range 25-61); all patients achieved radiologic union by a mean duration of 4.3 ± 1.2 months (range 3-8). The mean medial proximal tibial angle improved from 75.3° ± 3.7° (range 70.5°-85.2°) to a postoperative angle of 83.8° ± 3.6° (range 77.5°-90.4°) (P < .001). In 12 patients, an abnormal mean anterior slope of -5.5° ± 3.0° (range -1.1° to -13°) was corrected to a postoperative posterior slope of 5.8° ± 4.4° (range -1.1° to 14.1°) (P < .001). In 6 patients, a mean posterior slope of 17.4° ± 10.5° (range 1.4°-33°) was corrected to a postoperative posterior slope of 14.08° ± 5.6° (range 7.4-21.3) (P = .214). The mean knee outcome survey scores preoperatively were 25% ± 9.68% (range 8%-48%) and postoperatively were 85% ± 11.18% (range -52% to 98%, P < .001). CONCLUSIONS: MOTHO for varus malunited tibial plateau fractures is safe and effective procedure that provides excellent functional outcomes, acceptable radiologic outcomes, and carries minimal complications. LEVEL OF EVIDENCE Level IV, therapeutic case series.