Supramalleolar osteotomy for ankle valgus in myelomeningocele.

Fifty-five supramalleolar osteotomies were performed in 35 patients for progressive hindfoot valgus in myelomeningocele. All patients were ambulatory. The most common motor level of innervation was L3 in 42 limbs. The average age at surgery was 12 years. The average follow-up was 8 years. Preoperatively, all patients experienced progressive difficulty with brace use, and anteroposterior weight-bearing ankle radiographs showed a valgus tilt of the talotibial angle (TTA) of > or = 10 degrees with an average of 18 degrees. The average postoperative correction of TTA was 17 degrees. The results were graded as follows: excellent, 42 limbs; good, eight limbs; fair, three limbs; and poor, two limbs. The fair and poor limb results were the result of loss of correction or nonunion. The best results were seen when the TTA was corrected to 5 degrees of varus.