Clinical Evaluation of Direct Dorsal Column Stimulation

Inclusion Criteria: Subjects enrolled in this study must meet the following inclusion criteria: 1. Primary pain type-neuropathic with concordant neurologic findings 2. Subject age is 18 years or older; 3. Subjects who meet one of the following four criteria: 1. diagnosed with medically refractory chronic neuropathic pain, post laminectomy pain syndrome or failed back surgery syndrome. 2. previously had successful SCS, but gradually became refractory 3. did not have adequate coverage during a prior SCS trial, 4. been deemed refractory to all other treatments and would otherwise receive an intrathecal catheter/pump for chronic narcotics administration 4. Disease duration of at least 6 months with no lasting success with standard therapy and medications. 5. Mean pain intensity of at least 5 cm (or greater), measured on a visual analog scale from 0 (no pain) to 10 cm (severe pain) on a 10 cm line; 6. Psychological screening has been completed and the patient has been cleared by a psychologist or psychiatrist as a suitable SCS candidate; 7. Subject is willing to cooperate with the study requirements including compliance with the treatment regimen, the follow-up visit schedule and completion of the study diary; 8. Female candidates of childbearing potential must have a negative serum pregnancy test. 9. MRI or CT myelogram of the lumbar and thoracic spine (within 12 months prior to screening) rules out a pathology that might compromise SCS electrode placement or pathology, in addition to neural compression that might contribute to the subject's pain 10. Provide informed consent to participate in the study; - Exclusion Criteria: A subject will be excluded from participation in this study if they meet any one of the following criteria: 1. Pain attributed to: vascular disorder; musculoskeletal disorder; substance abuse or withdrawal; infection; disorder of homeostasis; 2. Subjects currently participating in another clinical trial; 3. Subject has an existing intrathecal drug pump 4. Active local or systemic infection 5. Unresolved issues of secondary gain (e.g., litigation) 6. Expected inability to adequately report treatment outcome 7. A concurrent clinically significant or disabling chronic pain problem or condition that is likely to confound evaluation of study endpoints (e.g., chronic migraine, significant arthritis of the hip associated with groin pain as primary complaint) 8. Radiographic evidence of frank instability (grossly mobile spondylolisthesis or abnorm…