Does An Intrathecal Baclofen Pump Affect Hypertonicity Of Upper Extremities?

Does an intrathecal baclofen pump, with the catheter in the lumbar intrathecal space, control or effect the hypertonicity of upper extremities or neck dystonia? Based on the literature, the infused baclofen acts locally- and therefore I am under the impression that the infused baclofen will have no effect proximally.