News and Advancements from the Department of Clinical Neurosciences. Spinal Cord Stimulation for Low Back Pain

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1 NeuroUpdate News and Advancements from the Department of Clinical Neurosciences Spinal Cord Stimulation for Low Back Pain Sanjay Patra, MD An estimated 70 percent to 85 percent of the adult population in the United States will suffer from an episode of low back pain (LBP) during their lifetime 1. Up to 5 percent of this group will see a physician or miss work due to this condition. Thus, LBP is recognized as the most common cause of lost work days in this country. It also is the most frequent cause of disability in people under age In most patients, an episode of LBP will spontaneously resolve. However, a number of patients develop recurrent episodes of acute LBP or chronic low back pain (CLBP), defined as LBP lasting three months or more. Typically, CLBP does not clearly originate from a defined pathology such as a fracture, infection, neural compression, neoplasm or deformity 1,3. The diagnostic dilemma in these patients arises from the inability to define the pain generator. Furthermore, degenerative MRI changes can be present in patients with or without CLBP. Based on cross-sectional studies, it is unclear whether there is a true association between MRI changes and CLBP 3. In fact, asymptomatic disk bulges are present in 54 percent of people age 20 to 39 and in 79 percent of patients over age Between 10 percent and 40 percent of patients undergoing spinal surgery will fail to have a long-term resolution of their lower extremity and lower back pain, referred to as failed back syndrome 8,9, and will develop chronic pain. Increased levels of pain have been correlated with depression, increased disability and diminished quality of life as well as implicated in decreased cognitive processing speeds, cardiac Figure D morbidity and diminished longevity. In addition, these factors create an expanding economic burden on the health care system. Thus, finding an efficacious, cost-effective and safe treatment modality for failed back syndrome is warranted. Action Points Contact Spectrum Health Direct at to arrange an adult patient transfer, direct admission or emergent consult with a Spectrum Health Medical Group neurologist. Download a referral form at spectrumhealth.org/neuromd and access referral guides and information about our programs and providers. The Spectrum Health Medical Group Department of Clinical Neurosciences holds divisional status with the Michigan State University College of Human Medicine.

2 Spinal cord stimulation (SCS) is a well-documented, minimally invasive procedure used for the past 30 years to effectively relieve lower extremity and LBP following previously failed spinal procedures. During the SCS procedure, leads are placed in the epidural space via open or percutaneous methods (Figure D). The electrical current produces a sensation of paresthesia that overlaps the region of pain and provides an analgesic effect (Figure A, B, C). Clinically, there is good evidence that SCS provides effective pain relief in select populations. Over the past decade, randomized controlled trials have shown SCS to provide superior pain relief, reduced narcotic usage, and increased cost-effectiveness relative to traditional revision surgery and the best medical management in patients with failed back syndrome 9,10,11. Prior to SCS, however, a patient must be evaluated for clinical evidence of neurologic deficit caused by nerve compression. In these patients, a conventional surgical procedure to decompress the nerve roots may be warranted to prevent further neurologic decline. Further research also is needed to elucidate the role of SCS in the treatment of axial back pain in patients who have not had previous back surgery. Spectrum Health Medical Group currently is collecting data on this population in a retrospective review and hope to publish the results within the next two years. A B C Figures A, B, C. Single-column and multi-column stimulation of the dorsal column of the spinal cord. Multi-column systems (Figure C) tend to be more effective in treating axial lower back pain. An Aging Population Means More Pain A recent Institute of Medicine report estimates 116 million adults are affected by chronic pain, with an associated annual economic cost of $635 billion 5. Chronic low back pain is affecting increasing numbers of this aging population. The number of spinal surgeries also will likely increase in proportion. Today, more than 38 million individuals are age 65 years or older. By 2030, individuals age 65 years or older will increase to an estimated 71 million, and those over age 80 will increase to an estimated 19.5 million 6. By 2050, for the first time in recorded history, the number of older persons will exceed younger people across the globe : The number will exceed younger people across the globe 2030: 71 million 2014: 38 million Individuals age 65 years or older

3 Spinal Cord Stimulation as Successful Alternative to Traditional Surgery The following describes the clinical course of a 68-year-old female with a long history of chronic lower back pain including numbness in her right leg. Conventional surgical approaches proved unsuccessful in managing her pain. In 2008, she underwent a lumbar laminectomy for nerve root decompression with no fusion. Her lower back pain continued, and in 2011, she had a second surgery with fusion. She experienced some pain relief, which lasted less than a year. Subsequently, the patient also developed degenerative disk disease next to the level of her previous fusion. At this point, she was given the option of another revision surgery with extension of her fusion but declined, citing the long recovery period and lack of sustained benefit from previous surgeries. Instead, the patient chose physical therapy and multiple lumbar epidural steroid injections. This course helped manage her back pain, but again, only for a short period of time. The patient reported pain levels in her lower back as 8 to 9 out of 10 and reported hip pain and right leg pain as 7 out of 10. Follow-up X-rays and MRI showed a fusion from L3 to S1 with no radiographic complications and some adjacent level mild stenosis at L23 not causing significant nerve root compression. Examination did not reveal any weakness or numbness in her lower extremities. Given the lack of responsiveness to conservative treatment measures following spinal surgeries, the patient opted for a spinal cord stimulator trial. Following the trial, her back pain levels improved to 0 to 1 out of 10 and leg pain to 1 to 2 out of 10. She subsequently underwent a permanent implant (Figure E,F). At three months follow-up, she reported no back or leg pain. Figure E, F. Spinal cord stimulator lead connected to pulse generator, which is typically implanted subcutaneously in buttock or flank. Most modern units are rechargeable, and MRI-compatible versions are now available. Spinal cord stimulation (SCS) is a welldocumented, minimally invasive procedure used for the past 30 years to effectively relieve lower extremity and low back pain following previously failed spinal procedures. Referrals and Consultations Sanjay Patra, MD Spine & Pain Management Center or sanjay.patra@spectrumhealth.org For more information, see page 7.

4 Neuromuscular Medicine Paul Twydell, DO Neuromuscular medicine is the diagnosis and management of disorders that primarily affect the peripheral nerves after they leave the spinal cord, the nerve and muscle junction, and the muscles the nerves eventually innervate. Many neuromuscular diseases are genetic. Some are caused by an immune system disorder. While many can be treated, most have no cure. The goal of treatment, therefore, is often to improve and manage symptoms, and extend survival while maintaining quality of life. management of neuromuscular diseases requires the extensive training and expertise of a fellowshiptrained neuromuscular medicine specialist in partnership with a multidisciplinary clinical team. In addition, specialized laboratory and genetic testing, electrodiagnostic studies, muscle, nerve and skin biopsy, and advanced imaging techniques complement the comprehensive evaluation of a patient with suspected neuromuscular disease. While at present, curative treatments for neuromuscular disorders are limited, the coming decade holds promise with many emerging targeted therapies and technologies such as stem cell therapy, personalized genomics, adenoviral gene therapy and advanced neuromuscular imaging. From amyotrophic lateral sclerosis (ALS), a progressive, lethal, neurodegenerative disorder that affects breathing, swallowing and limb strength, to autoimmune disorders, such as myasthenia gravis and inflammatory myopathies, that affect muscles and nerves, to muscular dystrophies and hereditary neuropathies, the recognition and Neuromuscular Disorders Amyotrophic lateral sclerosis Peripheral neuropathies (e.g., diabetic and immune-mediated neuropathies) Muscular dystrophies Congenital and acquired myopathies Inflammatory myopathies (e.g., polymyositis, inclusion body myositis) Neuromuscular transmission disorders (e.g., myasthenia gravis, Lambert-Eaton myasthenic syndrome)

5 Completing the Picture: Electrodiagnostics An electromyogram (EMG) and nerve conduction studies are often performed to confirm or further characterize a suspected neuromuscular disease. During an EMG, a small wire electrode is inserted into multiple muscles to record electrical signals. With nerve conduction studies, a small electrical current is applied to the body in multiple locations in order to determine how well electrical signals are traveling through a nerve. Nerve conduction studies are administered by a trained technologist; an EMG is completed by a trained physician. Results are often shared with the patient at the time of the visit and a detailed report is sent to the referring provider. Spectrum Health has five new stateof-the-art EMG laboratories to support our growing neuromuscular medicine program. Bringing Optimal Care to Patients in West Michigan To address the multiple complexities and challenges facing patients with neuromuscular disease, Spectrum Health continues development of a comprehensive neuromuscular medicine program. This includes dedicated multidisciplinary clinics located at our Integrated Care Campus, 2750 East Beltline NE, in Grand Rapids. Mounting evidence supports the use of multidisciplinary clinics in the treatment of neuromuscular disease. Advances in our understanding and application of noninvasive ventilation techniques, disease-specific symptomatic therapy, enteral feeding, augmentative communication and adaptive equipment have improved the quality of life and survival of those afflicted with neuromuscular disease. These can be instituted more easily in such a clinical setting. For patients with ALS, this evidencebased approach to care, initially promoted by the Quality Standards Subcommittee of the American Academy of Neurology, first in 1999 and then revised in 2009, has been shown to improve survival and quality of life. Paul Twydell, DO, a board-certified neurologist and fellowship-trained neuromuscular medicine specialist, leads a clinic team composed of a speech/language pathologist, respiratory therapist, physical therapist, licensed medical social worker and registered nurse manager. During a clinic appointment, a patient meets with each team member individually to address current needs, solve problems and identify potential issues that may arise once back in his or her home or work environment. Before and after each clinic, the team meets to review each case, determine the best course of treatment and coordinate care plans. For patients with ALS, this evidence-based approach to care... has been shown to improve survival and quality of life. Dr. Twydell leads ALS patient management conference with clinical team.

6 (Left to right): Lea Norbotten, MA, CCC-SLP, CBIS, Speech-Language Pathologist; Kenneth Harker, RRT, CPFT, Respiratory Therapist; Paul Twydell, DO, Director, Neuromuscular Medicine; Michele Weaver, PT, DPT, CBIS, NCS, Neurological Clinical Specialist; Martha VanDyken, LMSW, Medical Social Worker; Rebecca Kloote, BSN, RN, CNRN, ALS Clinic Coordinator Speech/Language Pathologist Addresses swallowing and communication issues Offers potential exercises and/or augmentative devices, respectively Helps determine need for more invasive treatments to address swallowing problems (e.g., placement of gastrostomy tubes to maintain caloric intake) Respiratory Therapist Evaluates pulmonary function and provides counsel on maintaining optimal pulmonary health Offers recommendations on most current noninvasive ventilator equipment (e.g., BiPAP and AVAPs) Physical/Occupational Therapist Evaluates mobility and provides exercises or other physical activity recommendations Suggests adaptive equipment to improve ability to complete normal activities of daily living Medical Social Worker Helps patients navigate insurance coverage issues, psychosocial aspects of dealing with chronic disease and end-of-life planning Nurse Manager Coordinates clinic schedule and maintains lines of communication among team Ensures implementation of diagnostic and therapeutic plans Referrals and Consultations To provide greater access to care, counseling, equipment and research opportunities for our patients, Spectrum Health also has established relationships with the ALS Association (ALSA) and the Muscular Dystrophy Association (MDA). Both organizations have long been patient advocacy champions. In the future, we hope to integrate our own clinical research opportunities for interested patients. Paul T. Twydell, DO Director, Neuromuscular Medicine or For More Information Traynor, B, et al. Effect of a multidisciplinary amyotrophic lateral sclerosis (ALS) clinic on ALS survival: a population based study, J Neurol Neurosurg Psychiatry. Sep 2003; 74(9):

7 Spinal Cord Stimulation for Low Back Pain For More Information 1. Andersson GB. Epidemiological features of chronic low-back pain. Lancet. 1999;354: Luo X, et al. Estimates and patterns of direct health care expenditures among individuals with back pain in the United States Jan 1;29(1): Chou D, et al. Degenerative magnetic resonance imaging changes in patients with chronic low back pain: a systematic review. Spine 2011 Oct 1;36(21 Suppl):S Boden SD, Davis DO, Dina S et al., Abnormal magnetic-resonance scans of the lumbar spine in asymptomatic subjects. A prospective investigation. J Bone Joint Surg Am. 1990; Mar.72 (3): National Academy of Science, U.S. Census Bureau, Winker MA, DeAngelis CD, Caring for an Aging Population. Call for Papers. JAMA, 2010;303: Wilkinson HA. The Failed Back Syndrome: Etiology and Therapy. Philadelphia, Harper & Row, 1991; ed North RB, et al. Spinal cord stimulation versus reoperation for failed back surgery syndrome: A cost effectiveness and cost utility analysis based on a randomized, controlled trial. Neurosurgery. 2007;61: North RB, et al. Spinal cord stimulation versus repeated lumbosacral spine surgery for chronic pain: a randomized, controlled trial. Neurosurgery. 2005;56(1):98-106; discussion Kumar K, 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: Frymoyer JW, et al. An overview of the incidences and costs of low back pain. Orthop Clin North Am 1991; 22: Loeser J, et al. Epidemiology of low back pain. Neurosurg Clin N Am. 1991;4: Chou R, et al. Surgery for low back pain: A review of the evidence for an American Pain Society clinical practice guideline. Spine. 2009; 34(10): Upcoming CME Programs spectrumhealth.org/neuromd Neurosciences Grand Rounds Neurosciences Symposium 1st and 3rd Wednesday of each month, 7:30 to 9:30 a.m. May 2015 Grand Rapids Grand Rapids

8 100 Michigan Street NE Grand Rapids, MI Nonprofit Org. U.S. Postage Paid Grand Rapids, MI Permit No. 251 Spinal Cord Stimulation for Low Back Pain Sanjay Patra, MD Neuromuscular Medicine Paul Twydell, DO Upcoming CME Programs spectrumhealth.org/neuromd November, 2014 NeuroUpdate News and Advancements from the Department of Clinical Neurosciences FY