Hip subluxation and dislocation in cerebral palsy: outcome of bone surgery in 21 hips.

The prevalence of hip subluxation and dislocation in cerebral palsy ranges between 3% and 75% in the literature. Clinical signs are rigidity, pain and instability. We assessed functionality, stability and symptoms in 20 patients preoperatively and after follow-up. A varus derotation osteotomy was performed in cases with subluxation or dislocation, while a Chiari osteotomy was performed in the presence of a concomitant acetabular dysplasia. Results were good in 64%, fair in 22% and poor in 14% of patients treated with a varus derotation osteotomy. In patients treated with a Chiari osteotomy, results were good in 43% of cases, fair in 43% and poor in 14%. Subluxated or dislocated hips generally show several anomalies: their severity is directly proportional to the degree of neurological impairment. In the most severe cases, correction of just one of such anomalies might not be sufficient to guarantee good results of the surgery.