A pilot study in patients with spastic gait to identify selectioncriteria for intrathecal baclofen therapy

ITB therapy has the potency to improve the walking capabilities of patients
with a spastic gait. At this moment potential candidates for ITB-therapy are
admitted during 1 week in the hospital for a test-infusion with ITB, to
determine whether their spastic gait can be improved with this therapy.
Selection for the ITB test-infusion currently is based on manual strength
testing of the mm. quadriceps femoris. Only patients with a strength of >=
grade 4 on the MRC scale will receive an ITB test-infusion. However, it is not
clear whether this is the best selection criterion for a successful ITB
test-infusion. Therefore, in this pilot study we want to assess the predictive
value of several tests, including manual strength measurement, to predict
successful test-infusion in patients with a spastic gait.

Primary Objective: To study which test or which combination of tests has the
best predictive value at baseline level for a positive effect of the ITB
test-infusion, rated by the patient on the Patient-Global Impression of Change
(P-GIC).

Secondary objective: To determine the correlation between the quantitative and
qualitative test scores within the 3 domains to be scored (strength,
spasticity, gait)

Pilot Study

All patients will receive ITB test-infusion at different dosages during 5 days
at the neurology ward.

During the currently used standard procedure, all candidates for ITB therapy
receive ITB test-infusions at different dose levels to study the clinical
effect of ITB. These test-infusions take place at the neurology-ward. The
dosages vary from 25-150 µg /day, with daily increases of 25ug, which are
infused, mostly as a bolus. The effects of ITB are currently measured using
only the modified Ashworth scale and the strength in the mm. quadriceps femoris
(MRC-scale). The ITB-dose is increased every day, until the optimal dose is
found (i.e. the dose at which the patient experiences optimal spasmolytic
effects).

During the pilot study a number of additional tests are performed to measure
the effect of ITB-therapy. All tests will be performed at baseline and after
each different bolus of ITB. All tests will be performed at the neurology ward.
None of the tests requires invasive procedures and the risks are equal to the
normal procedure.

This study can be performed only with the specific and small population of
patients with a spastic gait, who did not reach a satisfactory effect using
oral spasmolytic therapy. If patients are so spastic that they can not walk
anymore, complete paralysis accompanied by a total disappearance of spasticity,
is the final aim of ITB, for which no extra scales are necessary. However, no
studies have examined the optimal protocol for selection and monitoring of
patients with a spastic gait, who want to improve their walking capabilities by
using ITB. The information gathered during this pilot study will be used to
optimize the selection criteria for future patients with a spastic gait, which
hopefully will increase the number of patients benefiting from ITB-therapy.