Limitations of intrathecal baclofen for spastic hemiparesis following stroke

Intrathecal baclofen (ITB) has become the first choice in the management of deleterious spasticity that does not respond to oral and intramuscular medications following spinal cord injury, traumatic brain injury, and cerebral palsy. The usefulness of ITB in severe spastic hemiparesis following stroke is studied.

A total of 8 patients underwent clinical and video assessment following ITB bolus application (n=5) and during continuous infusion via a temporary catheter system (n=3).

The mean daily dosage alleviating spasticity on the hemiparetic side-without affecting the nonparetic side-was 119 microg/day (range 50 to 360 microg/day). However, 6 patients experienced functional deterioration as ITB weakened their paretic side such that the antigravity pattern they used for ambulation was suppressed. In 2 patients, spasticity-associated pain and spasms subsided and they underwent implantation of a long-term drug delivery system.

ITB may reduce spasticity in a dose-dependent manner irrespective of its origin. Although not primarily antinociceptive in humans, ITB may alleviate pain if arising from increased muscle tone. A functional benefit may result if ITB can uncover "subclinical" motor control that had been suppressed by spasticity. However, when a patient uses antigravity patterns for ambulation in the absence of more complex motor control, ITB may cause the loss of residual walking ability, which becomes a major limitation for patients with hemiplegic stroke.