Pilot Study to Examine the Feasibility of the Dynamic Interferential Spinal Cord Stimulation System™ (DISCSS™)

This investigation will be performed as a prospective, multicenter, open-label feasibility
study. Thirty (30) patients with back pain greater than leg pain who were candidates for
Spinal Cord Stimulation (SCS) and have successfully completed a percutaneous trial with a
commercially available SCS system will be trialed with a 3-4 day exposure to the
investigational DISCSS™ device. The trial will be conducted at 3-5 U.S. centers. The
percutaneous trial leads from the commercial system will be connected to the External Pulse
Generator of the DISCSS™ Trial System and the patients will be trialed for an additional
three to four days. The investigational product for this feasibility trial will be the
DISCSS™ system, not the commercially available trial SCS system. Exposure to the commercially
available trial SCS system will be considered background therapy. The purpose of the
background therapy phase is to establish baseline pain levels and determine patients'
eligibility to continue to the investigational phase of the trial using the DISCSS™ SCS phase
of the trial. Pain assessment and complications data from the commercial spinal stimulation
system will be collected during the background therapy phase. The pain and complications data
from the background therapy phase will not be analyzed in terms of the study endpoints.

Inclusion Criteria:

1. Age greater than 21 years and less than 80 years

2. Has a diagnosis of chronic neuropathic pain of trunk and limbs

3. Is eligible for and participating in a spinal cord stimulation trial of a commercially
available SCS trial system. Subjects will be evaluated at the end of the background
Commercial SCS Device phase for complications and appropriateness to continue to the
investigational phase with the DISCSS™ system. Complications from the background phase
with the commercial SCS device may include, but are not limited to unusual pain or
discomfort during the trial stimulation, local skin reactions or infection at the
implant site.

4. Has a Back Pain Score of minimum intensity 5.0 on a Numeric Rating Scale (NRS)

5. Has an NRS Back Pain Score that is greater than both Leg Pain Scores

6. Is not a candidate for revision surgery

7. Has completed a minimum of 6 weeks of conservative therapy (physical therapy,
anti-inflammatory medications, or similar therapies) with limited or no reduction in
back pain

8. Is willing to adhere to the warnings associated with the DISCSS™ system

9. Is willing to halt and/or modify the use of all prescription and over-the-counter
analgesics per the Investigator's direction during study participation

10. Is capable of providing written informed consent

11. Is able to comply with the requirements of study visits, follow-up phone visits and
self-assessment questionnaires

Exclusion Criteria:

1. Is a poor surgical candidate by determination of the Investigator

2. Is unable to operate or understand the use of the commercial or investigational Spinal
Cord Stimulator systems

3. Has an active systemic infection

4. Has exposure to shortwave, microwave or ultrasound diathermy at home or at work

5. Has occupational exposure to high levels of non-ionizing radiation such as radio or
cell phone transmission stations, facilities using radiofrequency heat sealers or
induction heaters, or electric power infrastructure controlled environments

6. Has an implanted cardiac system (e.g. pacemakers)

7. Is currently participating in another clinical study

8. Is currently pregnant or lactating, or not using adequate birth control

9. Has any untreated major psychiatric comorbidity

10. Has serious drug-related behavioral issues per Investigator's assessment

11. Has a bleeding complication or coagulopathy

12. Requires concurrent use of anticoagulant therapy such as heparin, warfarin,
rivaroxaban, dabigatran, apixaban, edoxaban, enoxaparin, fondaparinux

13. Is immunocompromised and at risk for infection

14. Has insulin-dependent diabetes not controlled through diet and/or medication

15. Has chronic pain related to malignancy

16. Is otherwise determined, based on the opinion of the Investigator to be an unsuitable
candidate for this study