High reoperation rates after early treatment of the subluxating hip in children with spastic cerebral palsy.

Hip subluxation and dislocation are well-recognized complications of spastic cerebral palsy. Alternatives for treatment include observation, bracing, or surgery. The purpose of this study is to compare the rates of reoperation and acetabular development after early soft tissue procedures with those of varus derotational osteotomies performed to maintain reduced hips in severely involved children. A series of 60 patients with spastic cerebral palsy and hip subluxation younger than 6 years who underwent primary bilateral hip surgery at one hospital between 1980 and 1996, with a minimum of 4 years of follow-up, were retrospectively reviewed. Fifty-two patients had spastic tetraplegia and 47 were nonambulators. Measures of proximal femoral and acetabular development were made via radiographic analysis. Twenty-two patients underwent primary bilateral soft tissue procedures. At a mean 6-year follow-up, there was modest improvement seen in mean femoral head coverage and little improvement seen in mean indices of acetabular development. Seventeen of these 22 patients (77%) underwent reoperation. Thirty-eight patients underwent primary bilateral varus derotational osteotomies. At a mean follow-up of 5 years, there was also modest improvement noted in mean femoral head coverage with little change in the mean indices of acetabular development. Twenty-eight of these 38 patients (74%) underwent reoperation. In this population of severely involved patients with spastic cerebral palsy, the reoperation rate was high. Acetabular remodeling did not reliably occur as a result of either early soft tissue or proximal femoral procedures when performed at an average age of 4 years.