Minimally-Invasive, Non-Opiate Treatments for Chronic Pain: New Frontiers in Neuromodulation Disclosures Consultant to Abbott/St. Jude Medical Principal investigator on several national clinical trials sponsored by Abbott/St. Jude Medical Robert D. Heros, MD Physiatrist / Interventional Spine Specialist Spinal Diagnostics Tualatin, OR Agenda Chronic Pain: A Large, Costly, Growing Problem Pain as a major health issue in the United States The Chronic Pain Continuum: Present and Future Affects about 100 million Americans More than heart disease, cancer, and diabetes combined Neuromodulation as an advanced treatment for pain Challenges & New Frontiers Cases Discussion Societal cost > $600billion annually 515 million workdays lost 40 million doctor visits 40% Back Pain Absences from Work 50% Common Cold
USA Opiate Use 1999-2015 No change in overall pain Americans reported Rx opiate sales quadrupled Rx opiate deaths quadrupled United States 2015 More drug overdose deaths than MVA / gun homicide combined More deaths from drug overdoses than HIV/AIDS in peak year 1995 Numbers still rising US Life expectancy fell for 1st time in 22 years Sources: CDC www.cdc.gov/drugoverdose/epidemic/ Scope of Problem Chronic Pain 650,000 opiate prescriptions/day 3,900 people/day begin using opiates non medically 580 people/day begin using heroin 80-90 opiate overdose deaths/day $20,000,000,000/yr in ED & inpatient care for opiate overdose $50,000,000,000/yr in health/social costs due to opiate abuse An entirely subjective, unpleasant sensory or emotional experience > 3 months duration May be difficult to clearly identify how/when it began Inverse Duration/Success Sources: HHS Opiate Fact Sheet, www.hhs.gov/opioids/about-the-epidemic
Types of Pain Nociceptive Somatic: skin, muscle, joint, bone, connective tissue Visceral: internal organs Dull, aching, pressure, stabbing Neuropathic Usually chronic Burning, electrical, paresthesias It s not the problem that causes our suffering; it s our thinking about the problem. Byron Katie Psychogenic Pain vs suffering Neuropathic Pain Can occur with or without direct nerve damage; from injury, surgery, disease, trauma Described as burning, itching, fire, stabbing, shooting, stinging, electrical pain Numbness and pain can (and often do) coexist simultaneously Conditions of Interest Failed Back Surgery/Postlaminectomy Syndrome Chronic postoperative hip/knee pain Post-herniorrhaphy/vasectomy pain Ilioinguinal neuropathy Chronic sciatica Peripheral neuropathy (diabetic, idiopathic, etc) Postherpetic neuralgia Post-traumatic/surgical neuropathic Pain Phantom/Residual Limb Pain Complex Regional Pain Syndrome (CRPS) Type I or II
Traditional Treatment Options Medications: NSAIDs/ASA/Tylenol, anticonvulsants, antidepressants, steroids, ketamine, opiates; topical agents Physical therapy: heat/cold, massage, exercise, range of motion preservation, TENS Cognitive behavioral therapy / Biofeedback Neuromodulation/Spinal Cord Stimulation The Traditional Chronic Pain Continuum Differentiald iagnosis RICE PT/Exercise CAM OTC Meds Tier 1 Pain Therapies Intervention & Injections Non-opiate Rx meds Surgery Perioperative opiates Tier 2 Tier 3 Tier 4 Neuro modulation (SCS) Implanted Pumps Chronic Opiates Cog/Psych The Worst-Case (Present?) Chronic Pain Continuum Diagnosis?? OTC Meds Opiates Tier 1 Pain Therapies Haphazard injections Emphasis on opiates incl. long-acting Premature surgery Unneccess. surgery Wrong-site surgery PeriOp opiates Long-term opiates Still no clear diagnosis CR opiates Tier 2 Tier 3 Tier 4 Neuro modulation (SCS) Implanted Pumps Chronic Opiate use & abuse Poor outcomes Neuromodulation
Neuromodulation The alteration of nerve activity through the delivery of electrical or chemical stimulation to targeted sites in the body, with the aim of normalizing and/or altering nerve function Encompasses intrathecal therapy, deep brain stimulation and spinal cord stimulation Spinal Cord Stimulation(SCS) Delivers electrical pulses to the epidural space & spinal cord Electrodes placed dorsal to spinal cord (C/T/L) Blocks/alters pain signals before they reach the brain and hopefully reduces pain Pacemaker for Pain A Brief History of SCS 2500 B.C.: Egyptian use of electrogenic fish 1920: Primitive external device 1950: 1st cerebral electrode implant 1970: 1st epidural neurostimulation 1980: FDA approval for chronic pain 2005: 1st rechargeable IPGs 2016: Fully body MRI compatibility 2016 New Frontiers
Benefits of Spinal Cord Stimulation Non-Opiate Trial Period to assess technology Non-Opiate Option for percutaneous or surgical implants Compared to other options: cost effective, minimally invasive, low risk Non-Opiate Process 1. Identify candidate 2. Educate, educate, educate 3. Surgical & mental health screening 4. Insurance authorization 5. SCS Trial 6. Post-trial evaluation 7. If successful trial, implant Patient Selection Screening Pain is felt to be largely neuropathic in origin Pain primarily in the spine, trunk or extremities; unilateral or bilateral Many insurances require input of a surgeon Most insurances require psychological screening More conservative therapies have not provided sufficient relief No contraindications to implantation exist
Insurance authorization Trial Period A simple, low-risk way for patients to determine if SCS is right for them Temporary version placed via epidural catheter for 5-10 days Close team monitoring / daily patient support No commitment Patient evaluates: % Pain relief Functional improvement Quality of Life Trial Procedure - Outpatient setting - Mild conscious sedation (MAC) - 15-20 minutes
Successful Trial Implant Options Surgical: thoracic laminectomy for paddle implant Minimum of 50% improvement Subjective or objective Numerical pain scores, level of function, activity tolerance, sleep, quality of life, etc Percutaneous: for electrode implant Evidence Based In selected patients with neuropathic pain related to FBSS/PLS, compared with conventional medical management alone, SCS improved: Pain relief Quality of life Functional capacity Patient satisfaction Reduction in Pain Reference Number of Patients Follow-Up Results Kumar 6 410 8 years 74% had >50% relief North 7 19 3 years 47% had >50% relief Barolat 8 41 1 year 50% 65% had good to excellent relief Van Buyten 9 123 3 years 68% had good to excellent relief Cameron 10 747 Up to 59 months (4.9 years) 62% had >50% relief or significantly reduced pain scores Reduction in Medication Use Reference Number of Patients Follow-Up Results North 7 19 3 years ~50% reduced their medications Van Buyten 9 123 3 years As a group, reduced medication use by >50% Cameron 766 up to 84 months 45% reduced their medications 10 Taylor 11 681 n/a 68% no longer needed analgesics
Improvement in Daily Activities Cost Effective Reference Number of Patients Follow-Up Results Barolat 8 41 1 year As a group, significantly improved function and mobility North 7 19 3 years As a group, improvements in a range of activities Mekhail et al. Clin J Pain 2004;20:462-486 Retrospective case review n=128 Return to Work Compared cost of health care utilization before and after SCS OPV, ED visits, Injections, MRI/CT, etc Reference Number of Patients Follow-Up Results Van Buyten 123 3 years 31% returned to work 9 Taylor 1133 n/a 40% returned to work 11 Dario 12 23 3 years 35% returned to work Post-Implant: significantly fewer events vs before Average per patient savings $30,000/yr Limitations of Spinal Cord Stimulation 50% of patients reduce their pain 50% New Frontiers New Targets: Dorsal Root Ganglion Stimulation Not good for very focal pain: groin, hip, knee, feet and toes Extremity pain responds better than axial spine pain Improvement tends to diminish somewhat over time for some patients New Waveforms: High Frequency; Burst DR An old friend: SCS
Dorsal Root Ganglion Dorsal Root Ganglion purely sensory structure located at each spinal nerve root home to specific nerves that relay sensory information to the brain each spinal root / DRG has information from specific peripheral nerves corresponding to different parts of the body Plays a critical role in the development & maintenance of chronic neuropathic pain An Attractive Target for Stimulation Purely sensory structure Minimal CSF Easily accessible via epidural space each DRG corresponds well to its dermatomal level plays a critical role in the development & maintenance of chronic neuropathic pain DRG Stimulation Electrodes placed on the DRG, not the spinal cord Significant improvements for focal neuropathic pain: groin, hip/knee, foot FDA approved February 2016 (T10- S2) First Oregon cases July 2016
SCS DRG ACCURATE Study Compared DRG vs SCS for peripheral causalgia/crps pain DRG is safe & superior Pain relief sustained at 1 yr after implant Mostly sensation free; when felt, 95% only in area of pain Improved pain, quality of life, and activity levels Deer T et al, Pain. 2017 Apr; 158(4): 669 681. Burst DR Stimulation HF-10 Stimulation Subthreshold stimulation that mimics natural neuronal firing patterns Stimulates the medial thalamic pathways Subthreshold stimulation 10,000 khz stimulation Suggestion of superiority with axial back pain SENZA trial; Kapural et al, Neurosurgery 2016
Case 1: Amber Case 1: Amber 26yo woman s/p gymnastics injury at age 7 and chronic knee pain Age 15: R knee arthroscopy Age 16: Osteoarticular allograft Age 20: microfracture/chondromalacia debridement Age 24: lateral meniscectomy/chondroplasty + lipogem Extensive PT, steroid inj, PRP, stem cells, viscosupplementation, oral & topical meds Severe CRPS symptoms of allodynia, hypersensitivity, burning pain, etc. Unable to work, play, or enjoy life at 26 TKA only other option (not an option) DRG Trial Case 2: Patti Right L3, L4 DRG Immediate resolution of allodynia End of trial: 95% pain relief 9 mo s/p implant: 100% resolution of neuropathic knee pain 55yo woman with 20 yrs back & leg pain Radicular pain in 30 s led to 5 surgeries 1996-2008 Left with severe back pain & neuropathic leg pain L>R Had failed years of PT, chiro, massage, injections, medications incl. gabapentin, opiates
Case 2: Patti Communication SCS trial Feb 2016 with excellent relief of leg/back pain Permanent SCS system implanted April 2016 Jan 2018: Overall 50-70% pain relief / improvement in function Improved quality of life, activity Off all medications Communication, Communication, Communication Primary Care<>Pain/Spine Specialist<>Surgeon Improves efficiency and expedites patient flow Minimal Time yields Maximum Benefit Strategies for Primary Care Early pt identification: Chronic Pain, Opiate use, Failed Surgery Quickly review past hx: PT/Chiro, CAM, Injections, Rx, surgeries & imaging Remember imaging limitations Does pt truly need to see a surgeon? Talk to your pain specialists Patient - Provider communication is always important; even more so with chronic pain, opiates, neuromodulation
The Ideal Chronic Pain Continuum? Benefits of an improved Continuum Less opiate use & abuse Improved function Improved QOL -Improved communication between caregivers Diagnosis RICE PT/Exercise CAM OTC Meds Tier 1 Pain Therapies Nonsurgical spine eval Precise etiology Dx/Tx Injections Multi-D team effort Neuromod evaluation Surgical evaluation Min.Invas. Cog/Psych surgery Tier 2 Tier 3 Tier 4 Better outcomes -Patient involvement in decision-making -Patient education and empowerment -Preference for long-term treatment options that are lower risk, less invasive, cost effective -Reduction in opiate use & abuse -Improved outcomes Citations Kumar K, Taylor RS, Jacques L, et al. Spinal cord stimulation versus conventional medical management for neuropathic pain: a multicenter randomized controlled trial in patients with failed back surgery syndrome. Pain. 2007;132:179-188. Kumar K, Hunter G, Demeria D. Spinal cord stimulation in treatment of chronic benign pain: challenges in treatment planning and present status, a 22-year experience. Neurosurgery. 2006;58(3):481-496. Kapural L, Doust M, Gliber B, et al. Comparison of 10-khz high-frequency and traditional low-frequency spinal cord stimulation for the treatment of chronic back and leg pain: 24-month results from a multi center, randomized, controlled pivotal trial. Neurosurgery. 2016. Mekhail et al. Clin J Pain 2004;20:462-486 North RB, Kidd DH, Farrokhi F, Piantadosi SA. Spinal cord stimulation versus repeated lumbosacral spine surgery for chronic pain: a randomized, controlled trial. Neurosurgery. 2005;56:98-106; discussion 106-107. Barolat G, Oakley JC, Law JD, North RB, Ketcik B, Sharan A. Epidural spinal cord stimulation with a multiple electrode paddle lead is effective in treating intractable low back pain. Neuromodulation. 2001;4:59-66. Van Buyten JP, Van Zundert J, Vueghs P, Vanduffel L. Efficacy of spinal cord stimulation: 10 years of experience in a pain centre in Belgium. Eur J Pain. 2001;5:299-307. Cameron T. Safety and efficacy of spinal cord stimulation for the treatment of chronic pain: a 20-year literature review. J Neurosurg Spine. 2004;100(3):254-267. Robert D. Heros, MD Spinal Diagnostics 6464 SW Borland Rd. Ste A-2 Tualatin, OR 97062 503-885-1515 roberth@spinaldx.com Taylor RS, Van Buyten JP, Buchser E. Spinal cord stimulation for chronic back and leg pain and failed back surgery syndrome: a Systematic Review and Analysis of Prognostic Factors. Spine. 2005;30:152-160. Dario A, Fortini G, Bertollo D, Bacuzzi A, Grizzetti C, Cuffari S. Treatment of failed back surgery syndrome. Neuromodulation. 2001;4(3):105-110. Mironer, E, et al. A Prospective Clinical Evaluation of a Rechargeable Implantable Pulse Generator (IPG): Final Analysis of the Sustainability of Spinal Cord Stimulation Therapy for Chronic Lower Back Pain. Poster presented at: 2011 Bi-Annual Meeting of the International Neuromodulation Society; May 25, 2011; London, England.