Safety and efficacy of intrathecal baclofen trials for the treatment of hypertonia: a retrospective cohort study

Abstract

OBJECTIVE Intrathecal baclofen (ITB) is an effective treatment for refractory hypertonia in children. ITB has long been effective for the treatment of spasticity, and indications have naturally evolved to include dystonia and mixed pediatric movement disorders (PMDs). The established uses for ITB trials are insurance prerequisite, mixed tone, and family request. Despite agreement for ITB therapy by a multidisciplinary group of subspecialists in a complex PMD program, insurance companies often require an ITB trial be performed. A longitudinal cohort was identified to determine the safety and efficacy of ITB trials and to determine the utility of test dosing in this population. METHODS Retrospective data analysis was performed for patients with hypertonia who underwent ITB bolus trials at the authors’ institution between 2021 and 2023. Nonmodifiable risk factors and clinical variables were collected. RESULTS Thirty-one patients (11 female) underwent 32 ITB trials. Of these patients, 67.7% had a diagnosis of mixed hypertonia, 32.3% pure spasticity, and 9.1% secondary dystonia. The mean age at test dose was 12.8 years, and 58.1% of patients were born premature. The mode Gross Motor Function Classification System score was 5. The mean difference in Barry-Albright Dystonia Scale (BADS) scores was −7.33 points (p = 0.01) at 2.5 hours postoperatively. The mean difference in upper-extremity modified Ashworth Scale (mAS) scores was −5.36 points (p = 0.003), and that for lower-extremity mAS scores was −6.61 (p < 0.001). In total, 21.9% of patients developed a post–dural puncture headache. Conversion to a permanent baclofen pump was performed in 22/32 (68.8%) patients. Of those who did not pursue pump placement, 1 patient had high surgical risk, 1 had an ineffective response, 1 had a bad reaction to the test dose and cited both regression and increased discomfort, and 2 declined despite an effective trial owing to family preferences. CONCLUSIONS ITB trials require hospitalization in some form and carry risks of procedural complications. The decision to pursue a trial should be made on a case-by-case basis by clinicians and should not be determined by insurance companies. The complication rate of ITB trials is high, and a test dose is unnecessary in this fragile population.