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

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.