Can You Stall a Baclofen Pump During a Magnetic Rod Lengthening?

Introduction: Baclofen pumps are susceptible to magnetic forces because of the internal drug delivery mechanism. Magnetically controlled growing rods, sometimes implanted in the patients who have pumps, are lengthened using a device that generates a magnetic field. No previous study has determined if the external remote controller (ERC) can stall a baclofen pump during a rod lengthening.

Methods: Two baclofen pumps were placed in proximity to the ERC while it generated a magnetic field. This process was repeated with variations in the distance between pump and ERC, speed (dose) of the pump, lengthening time, and position of the ERC relative to the pump. The presence or absence of a stall was recorded.

Results: To stall a baclofen pump, the ERC needed to be running consistently for at least 30 mm of lengthening. The pump would not stall if it was >1 cm away from the ERC. The pump was more likely to stall if it was positioned in front of or behind the magnetic field, as opposed to the center of the field.

Discussion: As long as the baclofen pump is >1 cm away from the ERC, the pump will not stall, regardless of the length of time the ERC generates a magnetic field.