Management of Chronic Pain in Military Patients With Injuries Sustained During Active Duty

The purpose of this study is to determine the degree to which spinal cord stimulation added to comprehensive medical management can provide increased relief of chronic pain in patients with injuries sustained while on active military duty, measured by patient assessments of pain.

The study population includes combat-injured patients and other patients injured while on active duty who experience chronic pain as a result of the injury and who receive treatment as active duty military personnel at Department of Defense facilities or through the Department of Veteran's Affairs. The population will include patients with pain related to limb amputation, and patients eligible for care in the Veteran's Administration Polytrauma Network program (Polytrauma Veterans) or for management of similar injuries within the Department of Defense health care system. Study subjects will have complex problems that are difficult to treat with current standard rehabilitative approaches. The circumstances of these patients' injuries create a substantial societal interest in determining and providing the best achievable rehabilitation, an interest that combines the expectation that medical science will advance the quality of medical care, practical benefits to subjects and society of returning patients to active duty or employment, and the moral imperative to support persons injured while defending our national security.

Eligibility Criteria:
Inclusion Criteria:

* Subject is a veteran or active duty service member injured while on active military duty receiving care for pain related to the injury(ies) in the Department of Defense health care system or through the Department of Veteran's Affairs.
* Subject is 18 years of age or older.
* The elapsed time since the active-duty injury leading to chronic pain is not less than 3 months.
* Subject reports constant or daily episodes of injury-related pain of at least moderate severity, graded 4 or higher on an 11-point NPRS (point estimate by subject and Investigator at time of enrolment based on overall pain or pain at a specific site). Pain may be nociceptive, neuropathic, or mixed. Phantom pain associated with amputation of an extremity or extremities is allowed.
* Attempts to control pain with commercially available systemic analgesics have not provided adequate relief, in the judgment of the managing physician and subject.
* Subject is able to localize site(s) of pain. At least one site of daily pain contributing to moderate severity (Inclusion Criterion 4) and intractability (Inclusion Criterion 5) must be in an extremity, or phantom pain at the site of an amputated extremity. If the extremity site of pain is not an amputated limb, then the pain must have a neuropathic component. This site is identified as the site of Target Pain (TP) for efficacy evaluations during the trial.
* Subject is an acceptable candidate for surgical placement of an indwelling spinal cord stimulation device.
* Subject is judged an appropriate candidate for treatment using the available techniques and interventions encompassed within the protocol's definition of comprehensive medical management.
* For the duration of the trial, subject is willing to limit interventions for control of chronic pain to those approved by the Investigator.
* The subject is judged psychologically appropriate for either treatment intervention, based on the impression of an interviewing psychologist or psychiatrist.
* Subject provides informed consent.

Exclusion Criteria:

* Subject experiences phantom pain associated with amputation of both an upper and lower extremity.
* Subject has headache or visceral truncal pain or other non-musculoskeletal pain as the only pain that results in constant or daily scores of ≥4 on the 11-point NPRS.
* Subject has spinal disease that would, in the judgment of the investigator, - Subject has ongoing chronic infection or a medical condition associated with an unacceptably increased risk of infection related to device implantation.
* Subject has a current diagnosis or history of psychosis, cognitive impairment, hallucinations, or unexplained loss of consciousness, whether or not related to a combat injury that, in the opinion of the investigator, would exclude the patient from participating in the trial.
* Subject has a cardiac pacemaker.
* Subject has any significant medical or psychiatric condition that would interfere with the conduct of the study or with the outcome measures.
* Subject is pregnant or is breast feeding.
* Subject has participated in any drug or device trial in the past 30 days.
* Subject has any planned elective or semi-elective surgery during the 6 months of the Primary Treatment Phase, including stump revisions or grafting.
* Subject has a psychological condition of great enough severity that it would unacceptably increase the medical risks associated with implantation and care of the devices required for the treatment on the CMM + SCS arm, or would likely interfere with the subject's ability to sustain participation in a research study of long duration. Investigators are encouraged to include the medical monitor and the coordinating investigator in discussions about individual candidate subjects who have psychological diagnoses as part of the polytrauma syndrome before enrollment or treatment on this protocol.