Natural history of scoliosis in spastic cerebral palsy

Summary

Background

Although the frequent occurrence of scoliosis in patients who have spastic cerebral palsy is well known and surgical treatment has often been recommended for these patients, little is known about the natural history of scoliosis in this population. We aimed to clarify the natural history of scoliosis from childhood through to adulthood and provide objective data on proper surgical indications for such patients.

Methods

The participants were 37 institutionalised patients with severe spastic cerebral palsy and scoliosis. All the participants had a series of radiographs taken, starting at a mean age of 7·8 years; they were followed up for an average of 17·3 years. We retrospectively reviewed radiographs and assessed the effect of five factors on progression of scoliosis: sex, degree of spasticity, initial physical capability, pattern of spinal curve, and location of curve.

Findings

Scoliosis usually started before the age of 10 years and progressed rapidly during the growth period. In many cases, even after growth had ended, continuous progression was seen. The mean magnitude of the curves at final examination was 55° (Cobb angle). In 11 (85%) of 13 patients who had a spinal curve of more than 40° before age 15 years, the scoliosis progressed to more than 60° by the time of the final examination. Meanwhile, in only three (13%) of 24 patients who had a curve of less than 40° at age 15 years, did the scoliosis progress to more than 60°. Severe scoliosis (≥60°) developed predominantly in those who had total body involvement (67%), were bedridden (100%), or had throacolumbar curves (57%).

Interpretation

The risk factors for progression of scoliosis in spastic cerebral palsy are: having a spinal curve of 40° before age 15 years; having total body involvement; being bedridden; and having a thoracolumbar curve. Patients with these risk factors might benefit from early surgical intervention to prevent progression to severe scoliosis.

Introduction

Severe scoliosis in patients with cerebral palsy often causes additional motor dysfunction, compromised pulmonary function, and increased nursing demands.1, 2, 3 Surgical treatment has been recommended for these patients in recent years. However, no consensus has been reached on the indications for early or preventive surgical intervention for scoliosis in cerebral palsy. Indeed, surgery has been done on the basis of various indications proposed by surgeons and institutions.4, 5, 6, 7, 8, 9, 10, 11, 12, 13 This is partly because the natural history of scoliosis and risk factors for progressive scoliosis await clarification. So far, very little information on the natural history of scoliosis in patients with cerebral palsy from childhood to adulthood has been reported.14, 15

To address this situation, we describe the results of a longitudinal study of scoliosis in which institutionalised patients with severe spastic cerebral palsy were followed up for 17·3 years. We also present an appraisal of the risk factors for progressive severe scoliosis and propose guidelines for surgical intervention in the early stages of this disorder.