Implanted Pump Systems for Treatment of Spasticity

Summary

In about one third of patients with violent spasticity due to spinal trauma, multiple sclerosis, and diffuse brain injury adequate control with oral antispastic medication cannot be achieved and successful rehabilitation is severely handicaped. In the past these patients were subjected to destructive chemical procedures or extensive surgery.

The authors present the results of management of uncontrollable spasticity by means of continuous intrathecal administration of baclofen with a totally implantable gas driven pump system (Infusaid). 30 patients were treated between June 1985 and January. 1987. The main indication was incapacitating spasticity resistant to oral treatment with baclofen and caused by spinal cord injury or lesion (11 patients), multiple sclerosis (11 patients), infantile cerebral palsy (3 patients) and cerebral injury, hypoxia or ischaemia (5 patients). Clinical assessment included spasticity scores, integrated electromyography (Iemg) and motography. Effective control for spasticity with mean reduction of Iemg by 55%, decrease of Ashworth’s score from 3 to 0 and improvement of life quality was obtained in all patients with daily dose of 10–800 micrograms of Baclofen. Voluntary resting motoricity was not impaired and there were no untoward central side effects. The excellent effect of intrathecal baclofen in comparison with oral therapy is explained by local, spinal GABAergic inhibitory action of the drug which is delivered directly into spinal subarachnoid space. Dose finding and dose adjustment is performed prior to pump implantation by intermittend injections into a subcutaneous port. The complications of the procedure were minor (catheter displacement, disconnection) and easily correctable. The only limitation of this method is the inability to reduce spasticity in selective muscle groups. Intrathecal long term infusion of Baclofen is an alternative to surgery in treatment of spasticity.