Neuromuscular function and radioanatomical form of the myelomeningocele hip.

Abstract

The aim of this study was to describe variants in neuromuscular function and radioanatomical form of the myelomeningocele hip based on the level of spinal paralysis. For this purpose, 84 hip joints of 44 children with myelomeningocele age 1 to 10.75 years were classified into five spinal paralysis groups. Using anteroposterior pelvic radiographs, the position of the capital epiphysis, represented by the epiphyseal angle, and the position of the greater trochanter apophysis, represented by the apophyseal angle, were evaluated. The epiphyseal angle of the five paralysis groups showed three categories of average values. The thoracic/thoracolumbar group had an average of 0 degree, groups 2 (distal L1/L2) and 3 (distal L3/L4) had average values of 5 degrees to 6 degrees, and groups 4 (distal L5) and 5 (distal S1) had average values of 13 degrees to 14 degrees. The average values of the apophyseal angle showed a characteristic curve: the values dropped from group 1 (67 degrees) to groups 2 (45 degrees) and 3 (34 degrees) and then rose in groups 4 (44 degrees) and 5 (52 degrees). The authors concluded that the insufficiency of the hip abductors leads to a reduction of the epiphysis angle, and the relative insufficiency of the small glutei compared with the knee extensors leads to a reduction of the apophysis angle.