The Impact of Intrathecal Baclofen on the Natural History of Scoliosis in Cerebral Palsy

Background: Intrathecal baclofen (ITB) is an effective treatment of spasticity in patients with cerebral palsy. However, several recent reports have raised concerns that the treatment may be associated with a rapid progression of scoliosis. The objective of this study was to further examine the effect of ITB treatment on the progression of scoliosis in patients with cerebral palsy. Methods: Spastic cerebral palsy patients who were ITB candidates were followed radiographically. Baseline Cobb angles of the primary curve were measured during the period of ITB pump insertion and at the most recent follow-up visit. Each patient was matched with a control patient by the diagnosis of cerebral palsy, age, sex, topographic involvement, and initial Cobb angle. The mean rate of change in Cobb angle was compared between ITB and control patients using paired t test. A multiple linear regression model was used to examine the difference, controlling for age, sex, topographic involvement, and initial Cobb angle. Results: Fifty ITB patients and 50 controls were included in the analysis. There was no statistically significant difference between the mean change in Cobb angle in ITB patients (6.6 degrees per year) compared with the matched control patients (5.0 degrees per year, P = 0.39). The results from the multiple regression analysis also failed to show a statistically significant difference (0.92 degrees per year difference between ITB patients and controls, P = 0.56). Conclusions: The progression of scoliosis in cerebral palsy patients with ITB treatment is not significantly different from those without ITB treatment. The findings suggest that patients receiving ITB experience a natural progression of scoliosis similar to the natural history reported in the literature. Level of Evidence: Level III.