Atlas of Knee Operative Procedures in Cerebral Palsy

Abstract

Knee problems are very common in children with cerebral palsy (CP). This includes increased knee flexion during stance phase, lack of knee flexion during swing phase, and torsional malalignment of the tibia. A very common problem is increasing muscle contracture as the child grows. The growth leads to hamstring contractures which are primarily treated with stretching exercises. However, for most children, it is not possible to maintain adequate length in hamstring muscles through the whole growth period, although it should be possible in most children to prevent the development of fixed knee flexion contractures. Many children will need to have a surgical procedure to address the problem of hamstring shortness usually by lengthening the tendons. Another common problem is spasticity and poor motor control of the rectus femoris muscle leading to poor knee flexion in swing phase. The treatment for this may involve rectus femoris transfer or distal resection. As the lack of knee extension becomes more severe and a fixed knee flexion contracture develops, the options for correction include posterior knee capsulotomy or distal femoral extension osteotomy. If an extension osteotomy is required, usually the patella needs to be brought more distal with either a plication or transfer of the origin of the patellar tendon. Another common problem which indirectly affects the knee is tibial torsion; both internal and external tibial torsion may occur in a child with CP. Correction of this usually requires an osteotomy of the tibia. The goal of this chapter is to provide a detailed surgical description of the indications, surgical technique, and postoperative management of these procedures around the knee joint in the child with CP.