Minimally Invasive Adductor Release With Obturator Block for Hip Subluxation in Cerebral Palsy: A Report of Two Cases

Cerebral palsy (CP) is the most common motor disability in childhood and presents with spasticity, increased tone, decreased range of motion, and difficulty with ambulation. Abnormal communication between the cerebrum and the motor fibers leads to functional deficits and long-term adverse sequelae. This case report focuses on hip dysplasia. Two children with CP who were 4.4 and 3.8 years at initial surgery had substantial hip dysplasia with migration percentages (MPs) by X-ray of 60 and 55 and Gross Motor Functional Classification System (GMFCS) levels of 4 and 5. Each patient underwent minimally invasive selective percutaneous myofascial lengthening (SPML) of the hip adductors and ethanol block of the obturator nerves, along with other indicated procedures. Follow-ups were four and six years for the two cases. Indications for surgery included adductor spasticity with contracture, brisk adductor reflexes, scissoring, and hip dysplasia. The goals were to relieve symptoms and to serve as temporizing measures prior to possible later hip reconstruction. Results showed that, in each case, the MP improved substantially. Case 1 was a child who initially took steps with assistance and became independent by age six, with GMFCS scores improving from 4 to 2. The MP improved from 60 to 35 over four years. Case 2 was a child of GMFCS 5 who could not stand or take steps. The MP improved from 55 to 25 over six years. In addition to the initial SPML surgery, he had a second SPML surgery 31 months later at age six. This case is noteworthy in that the child consistently used a hip abduction orthosis and an abducted wheelchair through the entire six-year follow-up period. In conclusion, some young children with a significant hip subluxation can achieve improvement following minimally invasive surgery at medium-term follow-up. Our two children each had special circumstances. One was more highly functioning and became an independent walker. The other had consistent use of a hip abduction orthosis and an abducted wheelchair.