Division of Workers' Compensation Medical Treatment Guideline ...
Spinal Cord Stimulation Something Old, Something New John C. Schumpert, MD, MPH, FACOEM Resources for Environmental and Occupational Health (REOH) Missoula, Montana Disclosures 2001 to present: Founder and Medical Director, REOH 2002 to present: Faculty Affiliate,
Center for Environmental Health Sciences, University of Montana 2011-2012, 2016-2018: Medical Director, Montana Department of Labor and Industry Outline Something old History of nerve stimulation and how it works
Who benefits from spinal cord stimulation Medical evaluation for spinal cord stimulator trial Something New new applications of spinal cord stimulation How they work History of nerve
stimulation Spinal Cord Stimulation (SCS), originally called Dorsal Column Stimulation, was first conceived in 1965 by Melzack and Wall who proposed the gate-control theory of pain. non-painful input closes the nerve "gates" to painful input, preventing pain signal from traveling to the brain stimulation by non-noxious input is
able to suppress pain Gate Control Theory Spinal cord stimulation hypothesized gate theory mechanism. Stimulation of A fiber fiber the gate and results in reduced input and weak activation. https://aneskey.com/spinal-cord-stimulation-implantation-techniques-2/ s closes History of nerve stimulation In
the first decade after introduction, SCS was extensively used and applied indiscriminately to a wide spectrum of pain disorders. The results at follow-up were poor and the method soon fell into disrepute. History of nerve stimulation In the United States, during the late 1970s and 1980s SCS was
used only in a few specialized pain centers. In Europe, SCS was not introduced until the early 1970s and had limited use. History of nerve stimulation In the last decades, there has been growing awareness that SCS might be reasonable treatment for patients with neuropathic pain.
History of nerve stimulation Several reasons for the increased use of SCS (Meyerson 2000) Identification of the relevant indications Improved design of electrodes, leads, and receivers/stimulators Substantial decrease in incidence of re-operations for device failure
Introduction of the percutaneous electrode implantation making SCS trial possible History of nerve stimulation Spinal cord stimulation (SCS) is used to treat certain types of chronic pain. An electrical generator delivers 40-50Hz pulses to a targeted spinal cord area. The exact mechanism of SCS is
poorly understood. Example SCS generator and leads https://www.epainassist.com/back-pain/using-spinal-cord-stimulator-for-relieving-back-pain-or-backache Examples of SCS leads http://www.bostonscientific.com/en-US/products/spinal-cord-stimulator-systems/scs_lead_portfolio.html Example of surgical SCS lead placement https://www.mayfieldclinic.com/PDF/PE-Stim.pdf
SCS placement on the dura mater https://aneskey.com/spinal-cord-stimulation-implantation-techniques-2/ Recognized SCS effects One therapeutic property of SCS is its effect sympathetic nerves The sympatholytic effect is responsible for effectiveness of SCS in: Peripheral
artery ischemia (Cook 1973) Coronary artery ischemia (Sandric 1984, Lanza 2001) Some cases of CRPS type I and II Recognized SCS effects The SCS sympatholytic effect appears to have a role in treatment of: Post-laminectomy
Neuropathic pain in upper or lower extremities related to post-laminectomy syndrome (so-called failed back or neck surgery syndrome) Complex regional pain syndrome (type I and II) Radiculopathy
Brachial and sacral plexopathy: traumatic, post-radiation therapy Arachnoiditis Painful peripheral neuropathy including idiopathic small fiber neuropathy, metabolic (diabetic), infectious (HIV), and toxic (chemotherapy-induced) neuropathy Stump pain (postamputation) Ischemic pain associated
with peripheral vascular disease Ischemic pain associated with refractory angina https://aneskey.com/spinal-cord-stimulation-implantation-techniques-2/ Visceral pain SCS indications associated with lower success rate Axial pain following spine surgery (back and neck) Post-herpetic neuralgia pain Phantom pain Post-thoracotomy pain
Incomplete spinal cord injury with complete or clinically distinguishable loss of posterior column function Central pain https://aneskey.com/spinal-cord-stimulation-implantation-techniques-2/ Who they might help Who benefits from SCS Approximately one third to one half of patients who qualify for SCS can
expect a substantial reduction in pain (i.e., at least 50% reduction in pain). Who benefits from SCS Most studies define SCS success as achieving 50% or more pain relief. (Kumar et al., 2007; North et al 2005) Some functional gains have also been demonstrated. (Barolat et al 1998; Barolat et al 2001; Deer et al 2014; Frey et al 2009; Kemler et
al 2000; Kumar et al 2007) Who benefits from SCS Functional gains may persist at three years of follow-up in patients who had an excellent initial response to SCS are highly motivated (Barolat
et al 1998; Barolat et al 2001; Deer et al 2014; Frey et al 2009; Kemler et al 2000; Kumar et al 2007) Who benefits from SCS There is some evidence that SCS is superior to: reoperation for persistent radicular pain after lumbosacral spine surgery.
(North et al 2005) conventional medical management for persistent radicular pain after lumbosacral spine surgery. (Kumar et al 2007) Who benefits from SCS Some evidence that SCS is superior to re-operation and conventional medical management for: severely
disabled patients who have failed conventional treatment and have Complex Regional Pain Syndrome (CRPS I) failed back surgery with persistent radicular pain Who benefits from SCS There is no evidence demonstrating SCS effectiveness with CRPS II. BUT, it is generally accepted that
SCS can be used for patients who have this condition. Who benefits from SCS SCS may be most effective in patients with CRPS I or II who received no relief From oral medications From rehabilitation therapy From therapeutic nerve blocks And
in whom the pain has persisted for longer than 6 months. (Barolat et al 1998, Deer et al 2017, Frey et al 2009, Kemler et al Medical and psychological evaluation Medical evaluation for SCS trial It is particularly important that patients meet all of the indications
before a permanent SCS is placed. Several studies have shown that workers compensation patients are less likely to gain significant relief than other patients (Hollingworth et al 2011). Medical evaluation for SCS trial The extremity pain should account for at least 50% or more of the overall leg and back pain experienced by the patient.
Contraindications for SCS trial Any contraindication for regional anesthesia such as uncorrected coagulopathy or infection Pregnancy (though there are reports of uneventful pregnancies and deliveries on SCS) Severe central canal stenosis Neurologic deficit that could be surgically treated
Contraindications for SCS trial Significant/progressive spine instability (e.g., severe osteoporosis) Need for frequent MRIs (e.g., multiple sclerosis) Unacceptable surgical risk Implanted pacemaker or AICD (though off label use of SCS in this setting has been reported) Previous lesion at dorsal root entry
Psychological evaluation for SCS trial A comprehensive psychiatric or psychological evaluation prior to the stimulator trial should be performed. Psychological contraindications: Cognitive impairment Active substance abuse Borderline personality disorder or
other psychiatric co-morbidities that preclude success (e.g., somatic Medical evaluation for SCS trial The psychological evaluation should include: standardized detailed personality inventory with validity scales (such as MMPI-2, MMPI-2-RF, or PAI), pain inventory with validity measures
(for example, BHI 2, MBMD), clinical interview complete review of the medical records Medical evaluation for SCS trial The psychological evaluation should demonstrate: No indication of falsifying information, or of invalid responses on testing.
No primary psychiatric risk factors such as psychosis, active suicidality, severe depression, or addiction Medical evaluation for SCS trial If moderate depression, job dissatisfaction, dysfunctional pain conditions are present, the psychological evaluation should demonstrate these are below the threshold for compromising the patients ability to benefit from
neurostimulation. Medical evaluation for SCS trial The psychological evaluation should demonstrate: The patient is cognitively capable of understanding and operating the neurostimulation control device. The patient is cognitively capable of understanding and appreciating the
risks and benefits of the procedure. Successful SCS trial SCS trial duration at least 3 to 7 days Patient experiences a 50% decrease radicular or CRPS in pain, which may be confirmed by visual analogue scale (VAS) or Numerical Rating Scale (NRS), and Patient demonstrates objective functional gains or decreased utilization of pain medications.
And now for something new! Something new Until recently, there was no evidence that supported SCS use for spinal axial pain. Studies demonstrated no improvement of axial pain with SCS and recommended against its use.
Something new The objective of traditional SCS is to induce comfortable paresthesia or tingling sensations (i.e., stimulate sensory A fibers), that overlap the existing distribution of pain by modulating C fiber neuronal activity. Gate Control Theory Spinal cord stimulation hypothesized gate theory mechanism. Stimulation of A fiber fiber the gate and results in reduced input and weak activation.
https://aneskey.com/spinal-cord-stimulation-implantation-techniques-2/ s closes Something new The success of traditional SCS in relieving pain has been correlated to the coverage of paresthesia over the painful body area(s) AND patient acceptance of the induced sensations.
Something new Paresthesia variability can also increase with postural changes and body movement. Can cause discomfort/pain Can cause subtherapeutic pain relief It can be difficult to obtain and maintain paresthesia over correct area(s) of pain.
Something new The Colorado Treatment Guidelines have been updated to include a study by Kapural et al concerning high-frequency spinal cord stimulation for treating axial pain This information will be included in the Montana U&T Guidelines Something new High
frequency SCS uses a pulse rate of 10,000 Hz instead of traditional 40-50 Hz. High frequency SCS does not: produce paresthesia to achieve pain relief. require paresthesia to achieve pain relief. (Xu et al 2017, Russo and Van Buyten 2014)
High vs low frequency SCS waveforms (Xu et al 2017) Something new There is some evidence that a high-frequency, 10 KHz spinal cord stimulator is more effective than a traditional low frequency 50 Hz stimulator in reducing both back (i.e., axial) pain and leg pain. (Van Buyten et al 2013, Russo and Van Buyten 2015, Xu et al 2017,
Kapural et al 2015) Something new Kapural et al (2015) studied 198 subjects with both back and leg pain Randomized in a 1:1 ratio to a treatment group across 10 comprehensive pain treatment centers 171 passed a temporary trial and
were implanted with an SCS system 90 subjects got high frequency SCS and 81 subjects got low frequency Kapural et al 2015 High frequency SCS
Low frequency SCS 84.5% of subjects had 43.8% of subjects had 50% reduced back 50% reduced back pain pain 83.1% of subjects had 55.5% of subjects had 50% reduced leg 50% reduced leg pain pain p<0.001 for both back and leg pain comparisons Relative ratio for responders was 1.9 (95% CI, 1.4 to 2.5) for back pain and 1.5 (95% CI, 1.2 to 1.9)
for leg pain Superiority of high frequency SCS over traditional SCS for leg and back pain was sustained through Something new The high frequency device appears to lead to greater patient satisfaction than the low frequency device. Probably because high frequency SCS does not produce paresthesias to achieve pain relief.
Something new-the downside Low frequency SCS requires recharging about twice per month. High frequency SCS requires daily recharging for 30 to 45 minutes. Something new-the upside United Kingdom study found high cost effectiveness of high frequency SCS compared to:
traditional non-rechargeable or rechargeable low frequency spinal cord stimulators re-operation (e.g., failed back syndrome) medical management (Annemans et al 2014) Summary SCS
can be effective in reducing neuropathic pain caused by wide variety of conditions. A thorough medical and psychological evaluation of the patient is needed before beginning a SCS trial. High frequency SCS may provide greater pain relief and patient acceptance than traditional low Question s? References
North, R. B., Kidd, D. H., Farrokhi, F., & Piantadosi, S. A. (2005). Spinal Cord Stimulation versus Repeated Lumbosacral Spine Surgery for Chronic Pain: A Randomized, Controlled Trial.
Neurosurgery, 56(1), 98-107. Kumar, K., Taylor, R. S., Jacques, L., Eldabe, S., Meglio, M., Molet, J., . . . North, R. B. (2007). Spinal cord stimulation versus conventional medical management for neuropathic pain: a multicentre randomised controlled trial in patients with failed back surgery syndrome. Pain, 132(1-2), 179-188. Barolat, G., Ketcik, B., & He, J. (1998). Long-term outcome of spinal cord stimulation for chronic pain management. Neuromodulation, 1(1), 19-29. Barolat, G., Oakley, J. C., Law, J. D., North, R. B., Ketcik, B., & Sharan, A. (2001). Epidural spinal cord stimulation with a multiple electrode paddle lead is effective in treating intractable low back pain. Neuromodulation, 4(2), 59-66. Deer, T. R., Mekhail, N., Provenzano, D., Pope, J., Krames, E., Leong, M., . . . Neuromodulation Appropriateness Consensus,C. (2014). The appropriate use of neurostimulation of the spinal cord and peripheral nervous system for the treatment of chronic pain and ischemic diseases: the Neuromodulation Appropriateness Consensus Committee. Neuromodulation, 17(6), 515550; discussion 550. Frey, M. E., Manchikanti, L., Benyamin, R. M., Schultz, D. M., Smith, H. S., & Cohen, S. P. (2009). Spinal cord stimulation for patients with failed back surgery syndrome: a systematic
review. Pain Physician, 12(2), 379-397. Kemler, M. A., Barendse, G. A., van Kleef, M., de Vet, H. C., Rijks, C. P., Furnee, C. A., & van den Wildenberg, F. A. (2000). Spinal cord stimulation in patients with chronic reflex sympathetic dystrophy. N Engl J Med, 343(9), 618-624. Kumar, K., Taylor, R. S., Jacques, L., Eldabe, S., Meglio, M., Molet, J., . . . North, R. B. (2007). Spinal cord stimulation versus conventional medical management for neuropathic pain: a multicentre randomised controlled trial in patients with failed back surgery syndrome. Pain, 132(1-2), 179-188. References
Frey, M. E., Manchikanti, L., Benyamin, R. M., Schultz, D. M., Smith, H. S., & Cohen, S. P. (2009). Spinal cord stimulation for patients with failed back surgery syndrome: a systematic review. Pain Physician, 12(2), 379-397. Kumar, K., Taylor, R. S., Jacques, L., Eldabe, S., Meglio, M., Molet, J., . . . North, R. B. (2008).
The effects of spinal cord stimulation in neuropathic pain are sustained: a 24-month follow-up of the prospective randomized controlled multicenter trial of the effectiveness of spinal cord stimulation. Neurosurgery, 63(4), 762-770; discussion 770. Hollingworth, W., Turner, J. A., Welton, N. J., Comstock, B. A., & Deyo, R. A. (2011). Costs and cost-effectiveness of spinal cord stimulation (SCS) for failed back surgery syndrome: an observational study in a workers' compensation population. Spine (Phila Pa 1976), 36(24), 2076-2083. Annemans, L., Van Buyten, J. P., Smith, T., & Al-Kaisy, A. (2014). Cost effectiveness of a novel 10 kHz high-frequency spinal cord stimulation system in patients with failed back surgery syndrome (FBSS). J Long Term Eff Med Implants, 24(2-3), 173-183. Van Buyten JP, Al-Kaisy A, Smet I, Palmisani S, Smith T. High-frequency spinal cord stimulation for the treatment of chronic back pain patients: results of a prospective multicenter European clinical study. Neuromodulation. 2013 Jan-Feb;16(1):59-65; discussion 65-6. Kapural, L., Yu, C., Doust, M. W., Gliner, B. E., Vallejo, R., Sitzman, B. T., . . . Burgher, A. H. (2015). Novel 10-kHz High-frequency Therapy (HF10 Therapy) Is Superior to Traditional Lowfrequency Spinal Cord Stimulation for the Treatment of Chronic Back and Leg Pain: The SENZARCT Randomized Controlled Trial. Anesthesiology, 123(4), 851-860.
Russo M, Van Buyten JP. 10-kHz High-Frequency SCS Therapy: A Clinical Summary. Pain Med. 2015 May;16(5):934-42. Xu J, Liu A, Cheng J. New advancements in spinal cord stimulation for chronic pain management. Curr Opin Anaesthesiol. 2017 Dec;30(6):710-717. Melzack R, Wall PD. Pain mechanisms: a new theory. Science 965;150(3699):9719. References
Meyerson BA, Linderoth B. Mechanisms of spinal cord stimulation in neuropathic pain. Neurological Research 2000;22(3):28592. Cook AW, Weinstein SP. Chronic dorsal stimulation in multiple sclerosis. Preliminary report. New York State Journal of Medicine 1973;73:286872. Sandric S, Meglio M, Bellocci F, Montenero A. Clinical and electrocardiographic improvement of ischaemic heart disease after spinal cord stimulation. Acta Neurochir Suppl(Wien ) 1984;33:5436.
Lanza GA, Sestito A, Sandric S, Cioni B, Tamburrini G, Barollo A, et al. Spinal cord stimulation in patients with refractory anginal pain and normal coronary arteries. Italian Heart Journal 2001;2(1):2530. Kemler MA, Barendse GA, van Kleef M, De Vet HC, Rijks CP, Furnee CA, et al. Spinal cord stimulation in patients with chronic reflex sympathetic dystrophy. New England Journal of Medicine 2000;343(9):61824. North RB, Kidd DH, Lee MS, Piantodosi S. A prospective, randomized study of spinal cord stimulation versus reoperation for failed back surgery syndrome: initial results. Stereotactic & Functional Neurosurgery 1994;62(1-4):26772. Tesfaye S,Watt J, Benbow SJ, Pang KA,Miles J,MacFarlane IA. Electrical spinal-cord stimulation for painful diabetic peripheral neuropathy. Lancet 1996;348(9043):1698701. Meglio M, Cioni B, Rossi GF. Spinal cord stimulation in management of chronic pain. A 9-year experience. Journal of Neurosurgery 1989;70(4):51924. Meglio M, Cioni B, Prezioso A, Talamonti G. Spinal cord stimulation (SCS) in deafferentation pain. Pacing Clin Electrophysiol 1989;12(4 Pt 2):70912.
Meglio M, Cioni B, Prezioso A, Talamonti G. Spinal cord stimulation (SCS) in the treatment of postherpetic pain. Acta Neurochir Suppl (Wien ) 1989;46:656. Kumar K, Nath R, Wyant GM. Treatment of chronic pain by epidural spinal cord stimulation: a 10-year experience. Journal of Neurosurgery 1991;75:4027.
Schizophrenia: Jeopardy-style game that teaches you about the characteristics of this complex disorder. Research: Questions neuroscientists ask and the research methods they use to try to answer them. ... In which author's novel is it "always winter but never Christmas"?...
Chapter Thirty-Two Production Exchange Economies (revisited) No production, only endowments, so no description of how resources are converted to consumables. General equilibrium: all markets clear simultaneously. 1st and 2nd Fundamental Theorems of Welfare Economics. Now Add Production ...
Case Examples. Ms. D is 78 yo, has OSA, DM2, HTN, dyslipidemia, and is brought in by her daughter as she complains of frequent HA and fatigue. Not a "happy personality," her mood is always low and she feels like...
Derek Nowrouzezahrai Karan Singh Introduction Goal: A signal processing approach to obtain Maximum Likelihood (ML) estimates of surface derivatives. Contributions: automatic outlier rejection adaptation to local features and noise curvature-driven surface normal correction major accuracy ...
The Revolution Goes Radical. France, on the brink. Execution of Louis XVI led to war between France and rest of Europe (Austria, HRE, Great Britain, Prussia, Spain, Portugal, French Royalists, Italian states) Massive inflation. Sans culottes (poor laborers), Jacobins riot....
Chapter 7 Hypothesis Testing 7-1 Overview 7-2 Basics of Hypothesis Testing 7-3 Testing a Claim About a Proportion 7-4 Testing a Claim About a Mean: Known 7-5 Testing a Claim About a Mean: Not Known 7-6 Testing a Claim About...
0 = 8.85×10-12 C2N-1m−2 (from Data Booklet). ... Many of the formulas we use in IB physics are easily derived using both differential and integral calculus. Although IB requires you to use the resulting formulaic solutions to the differential equations,...
Ready to download the document? Go ahead and hit continue!