What is a baclofen pump and how is it put in?

Implanted device: Baclofen pump is used to treat chronic spasticity of lower extremities not treatable with oral medications. The pump is a sophisticated self contained pump that can deliver small volumes of medications (Baclofen in this case) constantly at a programmable rate, into the spinal fluid compartment in the lumbar spine, via a small silastic (plastic tube). Everything is implanted under the skin.