Study design: Retrospective radiographic and medical chart review with matched control group.
Objective: To identify the effect of intrathecal baclofen on the incidence of scoliosis, rate of curve progression, and pelvic obliquity compared with a matched cohort.
Summary of background data: Although intrathecal baclofen therapy (ITB) has been shown to be effective in decreasing spasticity, case reports have described some children receiving ITB in whom progressive scoliosis was noted; other authors have described no effect on the spinal column. A controlled study has not been performed.
Methods: All patients with spastic CP treated with ITB between 1997 and 2003 at a single institution were reviewed. A total of 107 patients undergoing ITB for a minimum of 2 years were identified, of which 26 patients subsequently developed or had progression of scoliosis. Twenty-five age, gender, and gross motor function classification system (GMFCS) score-matched quadriplegic CP patients with scoliosis who did not receive ITB constituted the control group used to compare the rate of curve progression and pelvic obliquity.
Results: The average curve progression for the baclofen group after pump implantation was 16.3 degrees per year; and for the control group was 16.1 degrees per year. Both groups' curves progressed over time during growth (P = 0.001), but baclofen did not have an independent effect on curve progression (P = 0.181). Average pelvic obliquity for the 2 groups increased over time (P = 0.001), but there was no difference between the groups (P = 0.536). Twelve of 57 patients (21%) developed scoliosis after pump implantation during a mean of 3.6 years of follow-up. Thirty of 92 matched control patients (32%) not treated with ITB within the same time interval had scoliosis by maturity.
Conclusion: This study demonstrates that ITB has no significant effect on curve progression, pelvic obliquity, or the incidence of scoliosis when compared with an age, gender, and GMFCS score-matched control group of patients with spastic CP without ITB.