Distal baclofen pump catheter migration associated with far-lateral paraspinal surgical placement

Objectives.  The increased rigidity and spasms implicit to patients being treated with baclofen provide a potential source of drug delivery system-related complications. Placement of the intrathecal catheter from the far-lateral paraspinal approach has been advocated to avoid catheter fracture as previously reported with a midline approach. A thin fascial layer and increased muscle bulk laterally could increase motion of catheters placed in this position. The authors report on a series of patients found to have spinal catheter migration out from the thecal sac following a far-lateral paraspinal surgical approach. Materials and Methods.  The medical records of six consecutive patients who required revision of an intrathecal baclofen infusion system secondary to spinal catheter migration were included in this retrospective review. Each patient failed to respond to oral antispasmodic therapy and showed a positive response to a trial of intrathecal baclofen before initial pump implantation. Clinical notes and operative reports were reviewed. Results.  All patients had a baclofen pump inserted with the intrathecal catheter placed through the far-lateral portion of the paraspinal musculature entering above the lumbar vertebral pedicle. In all cases, the spinal catheter migrated and was found coiled outside of the thecal sac. In two patients, this occurred on two separate occasions. Mean time to catheter revision following implantation was 7 ± 2 months. Conclusions.  Spinal catheter migration from the subarachnoid space can occur with intrathecal baclofen infusion systems. Alternative methods for spinal catheter placement warrant further study.