Hypotonic and Special Hip Problems in Cerebral Palsy

Abstract

Children with cerebral palsy (CP) most commonly have increased tone with spasticity or a mixed movement disorder. Although less common, hypotonia can also be the predominant muscle tone pattern. Many children with hypotonia are able to do some functional level of walking; however, these children are at increased risk of hip dysplasia, both subluxation and dislocation. These children should be included in the hip surveillance program with regular X-ray frequency based on the established age, Gross Motor Function Classification System (GMFCS), and last hip migration percent (MP). Hips in children with hypotonic CP should be treated when there is evidence of progression or severe subluxation with MP >60%. There is no good data to base treatment recommendations, natural history, or treatment outcome. Children with CP may also have Down syndrome and develop hip dysplasia and dislocation. If the child has ambulatory ability, treatment of the hip is recommended. However, if the child is nonambulatory, treatment is more difficult, and typically the hips remain mobile and pain-free through adolescence; surgical treatment is not recommended. Children with CP may also have developmental hip dislocation (DDH) from infancy. These hips should be treated using the DDH protocol if the baby’s medical condition is stable. The outcome of these hips is less predictable. Slipped capital femoral epiphysis (SCFE) and Perthes disease are rare in the child with CP; however, when they occur, treatment is recommended using the typical SCFE or Perthes protocol.