Disclosures. Agenda. Chronic Pain: A Large, Costly, Growing Problem

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1 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

2 USA Opiate Use 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 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 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,

3 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

4 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

5 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

6 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

7 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) minutes

8 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 years 74% had >50% relief North years 47% had >50% relief Barolat year 50% 65% had good to excellent relief Van Buyten years 68% had good to excellent relief Cameron 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 years ~50% reduced their medications Van Buyten years As a group, reduced medication use by >50% Cameron 766 up to 84 months 45% reduced their medications 10 Taylor n/a 68% no longer needed analgesics

9 Improvement in Daily Activities Cost Effective Reference Number of Patients Follow-Up Results Barolat year As a group, significantly improved function and mobility North years As a group, improvements in a range of activities Mekhail et al. Clin J Pain 2004;20: 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 years 31% returned to work 9 Taylor 1133 n/a 40% returned to work 11 Dario 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

10 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

11 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 Apr; 158(4): 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

12 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 Left with severe back pain & neuropathic leg pain L>R Had failed years of PT, chiro, massage, injections, medications incl. gabapentin, opiates

13 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

14 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: 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): 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 Mekhail et al. Clin J Pain 2004;20: 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 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: 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: 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): Robert D. Heros, MD Spinal Diagnostics 6464 SW Borland Rd. Ste A-2 Tualatin, OR 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: Dario A, Fortini G, Bertollo D, Bacuzzi A, Grizzetti C, Cuffari S. Treatment of failed back surgery syndrome. Neuromodulation. 2001;4(3): 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.