Outcomes of Tibial Derotational Osteotomies Performed in Patients With Myelodysplasia.

Abstract

Rotational deformities of the tibia are common in patients with myelodysplasia. The current recommended treatment is tibial derotational osteotomy to improve gait biomechanics. Previously reported complication rates are widely variable. The purpose of this study is to review the outcomes of derotational osteotomies as a function of complication and revision surgery rates as compared with previous studies. A retrospective chart review was performed on all tibial derotational osteotomies performed in patients with myelodysplasia from 1985 to 2010 in patients older than 5 years with > 2 years of follow-up. Charts were reviewed for demographics, amount of derotation at index surgery, incidence of complications, and the need for repeat derotational surgery. Descriptive statistics were used to determine the incidence of complications as well as need for reoperation. Further analysis was performed using Fisher Exact Test and the Student t test to identify independent risk factors for complication and rerotation. Eighty-two patients (129 limbs) had sufficient data for inclusion. The average follow-up was 7.15 years. Surgery was indicated for symptomatic torsion measuring > 20 degrees. The average amount of derotation was 28 ± 12 degrees. The incidence of complications was 10.85%, with a 3.10% incidence of major complications including fracture, deep infection, and hardware failure. The repeat derotation rate was 16.28%, all in patients initially treated for external tibial torsion. Age at initial surgery had no effect on complication rate or need for reoperation. Level of spinal involvement was not associated with complication risk; however, lumbar-level involvement was an independent risk factor for rerotation. With meticulous operative technique, derotational osteotomy of the tibia in patients with myelomeningocele remains a safe and effective method to treat tibial torsion, with an acceptable overall complication rate of 10.85% and a major complication rate of 3.10%. The data presented will aid providers in appropriate counseling of patients considering tibial derotational osteotomy.