Anterior release for fixed flexion deformity of the hip in spina bifida

We reviewed the results of anterior hip release for fixed flexion deformity in 57 hips in 38 children with spina bifida at an average follow-up of 8.9 years (2 to 22). The indication for this operation was a fixed flexion deformity of more then 30 degrees which interfered with function. In 43 hips there was a good outcome in that the fixed flexion deformity remained less than 30 degrees at follow-up. Four hips had a good initial result but deteriorated after an average of five years, and ten had a poor outcome with deformity of over 30 degrees. Six hips required a repeated anterior hip release and two of these were successful. The success of anterior hip release could not be related to the neurological level or the age at operation. Successful surgery correlated with the walking ability of the child at the latest follow-up.