Chronic pain below the neck present for a minimum of one year.

Diagnosis of at least one of the following:

* back pain with or without leg pain,

* post-herpetic neuralgia,

* complex regional pain syndrome (CRPS) 1 or 2,

* diabetic neuropathy,

* or a general neuropathic condition; medically stable and able to undergo surgery for implantation of the drug infusion system.

A Safety and Effectiveness Study of Intraspinal Gabapentin (MDT2004) for the Treatment of Chronic Pain