Patient Selection Checklist Including Psychological Considerations
By Alexios Carayannopoulos, DO, MPH
Medical Director, Comprehensive Spine Center, Rhode Island Hospital
Assistant Professor of Neurosurgery, Brown Medical School
The overall success of spinal cord stimulation therapy (SCS) is dependent upon careful patient selection, which influences the outcome of the SCS trial, implant, as well as maintenance of therapy. As with any interventional pain procedure, patients should undergo an appropriate screen, including a detailed history encompassing medical and psychological health, physical examination, and appropriate diagnostic studies, which include laboratory and radiologic tests. This process should assess for conditions that are SCS responsive and should also identify contraindications to therapy.
Patients with appropriate neuropathic pain conditions who have failed or plateaued despite engagement in a multi-modal treatment paradigm, including trial of adjuvant and/or opiate medications, trial of physical/occupational therapy, trial of interventional spine injections, trial of complementary and alternative medicine options, trial of psychological co-management of pain, and finally failed surgical trial should be considered for SCS therapy. SCS should be considered sooner than later in this paradigm to treat pain optimize/maintain function. The work-up for SCS should include education of the patient as to the basic mechanism of action, role of SCS in overall pain rehabilitation, as well as a procedural description of both the trial and implant phases with an understanding of associated limitations. Most importantly, patients should have realistic expectations as to appropriate goals of SCS therapy.
At present, the FDA has approved SCS as a tool to manage chronic intractable pain of the trunk and limbs, including unilateral or bilateral pain associated with failed back surgery syndrome, intractable low back pain, and leg pain. Off-label indications include management of ischemic pain in peripheral vascular disease and angina, mechanical low back pain, and peripheral nerve stimulation. Higher success rates have been seen with the following diagnoses: failed back surgery syndrome (FBSS), radiculopathy, plexopathy, arachnoiditis, epidural fibrosis, painful peripheral neuropathy, multiple sclerosis, complex regional pain syndrome. Reduced success has been seen in axial pain associated with FBSS, post-herpetic neuralgia, post-thoracotomy pain, phantom pain, intercostal neuralgia, and incomplete spinal cord injury.
Candidates for SCS should have both medical and psychological assessments prior to trial. Medical contraindications include anatomic variations, which would preclude safe placement of electrode or battery, coagulopathy issues, untreated infection, and cardiac defibrillator. Psychological assessment by a trained specialist should exclude instability, secondary gain, substance abuse, and severe cognitive impairment. Finally, written informed consent should be detailed/documented despite the low risk of SCS therapy.
Deer TR et al. The appropriate use of neurostimulation of the spinal cord and peripheral nervous system for the treatment of chronic pain and ischemic disease. The neuromodulation appropriateness consensus committee. Neuromodulation 2014; 17: 515-550.
Kreiss PG, Fishman SM. Spinal Cord Stimulation Percutaneous Implantation Techniques. Oxford University Press. 2009.