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Wearable Intensive Nerve Stimulation: Can It Have An Impact For Chronic Lower Extremity Pain?
These authors discuss the use of wearable intensive nerve stimulation, an emerging form of transcutaneous electrical nerve stimulation, and provide a few illuminating case studies.
Pain is a substantial and common complaint for millions of Americans, and is one of the most common reasons for visits to the doctor. Epidemiological data suggests that the prevalence of musculoskeletal and neuropathic pain increases with age until at least late midlife, and over half of these patients experience pain of a chronic nature.1
The definition of pain is multifaceted with a highly subjective component.2 Pain can impact the behavior of an individual, leading to social withdrawal and impaired mobility while patients face a financial burden due to increased healthcare costs.3 We spend billions of dollars annually, directly and indirectly, on managing chronic pain in the United States.4
We can categorize pain according to the body system affected. Neuropathic pain is one such classification, defined by damage to the nervous system and of which the physiologic changes remain poorly understood. It is difficult to note neuropathic pain as an autonomous occurrence as it usually presents secondary to the primary illness, whether that be a malady or trauma.5 Neuropathic pain is associated with poor quality of life in comparison to other severe disease processes and is therefore a social and economic burden on patients and healthcare systems.6
The treatment and management of chronic pain are gray areas. The optimal pain treatment uses a multimodal approach with a combination of pharmacological and non-pharmacological strategies.7 The main goals are to maximize quality of life and the functional capacity of patients.8 Conventional pharmacotherapy, such as analgesics, antidepressants and anticonvulsants for painful neuropathy, continues to be geared toward symptoms.9 Some patients, however, find limited efficacy with pharmacotherapy while others, especially those battling concomitant psychiatric complications, are often non-adherent to the pharmacotherapy regimen.10 Patients often will turn to non-pharmacological methods either in place of or in addition to pharmacological agents for pain relief.
Hot-cold treatments, massage therapy, electrical stimulation and acupuncture are a few of the treatment modalities patients utilize to alleviate pain without the adverse effects of a pharmacological agent.11 One such treatment modality, known as transcutaneous electrical nerve stimulation (TENS), is a non-invasive therapeutic that can treat a variety of painful conditions. Electrodes apply electrical stimulation to the skin, based on the gate control theory of pain, to stimulate large afferent nerve fibers of a low threshold. Users can vary the frequency from low to high, which will activate central versus peripheral mechanisms to induce relief.12,13 Researchers believe the mechanisms behind its therapeutic effects are stimulation of endogenous opioid release and modified electrical transmission and dilation of blood vessels.13–16
Clinical evidence has demonstrated the effectiveness of TENS for the treatment of chronic pain.17-19 Wearable Intensive Nerve Stimulation (WINS) is an emerging form of TENS that is FDA-cleared for the treatment of chronic pain (Quell, NeuroMetrix). The device is wearable, automated, designed for intensive use and enables regular use throughout the day, which is essential for the management of chronic pain.20 It is based on the patented OptiTherapy® technology, which automatically adjusts therapy to deliver optimal relief. Patients can also wear the device 24/7.
A Closer Look At Five Case Studies Involving Wearable Intensive Nerve Stimulation
The following five cases illustrate the use of the WINS device in the management of chronic pain.
Case 1. A 35-year-old male diagnosed with painful diabetic peripheral neuropathy of two years duration presented with 4/10 baseline pain on the Visual Analogue Scale (VAS). Before starting WINS, the patient was taking 100 mg of gabapentin three times a day and was requesting an increased dosage due to increased pain. The patient felt complete pain relief after wearing the WINS device for two days and did not require pain medications for three months. After a year of using WINS, the patient’s pain decreased to a 2/10 and the patient resumed his original medication regimen of 100 mg of gabapentin three times daily. The patient credits the WINS device for helping control the pain and preventing the need for increased medications.
Case 2. A 47-year-old female diagnosed with painful diabetic peripheral neuropathy presented with 3/10 baseline pain on the VAS. The patient was symptomatic for five years. Her previous treatments consisted of 300 mg of gabapentin three times a day and she complained of worsening symptoms. With the WINS device, the patient’s pain decreased from a 3 to a 2/10 without requiring an increase in the dose of medication. At one year, the patient continues to wear the device along with her original regimen of 300 mg of gabapentin three times daily. She feels the WINS device helped control the pain and prevented the need for increased doses of medications.
Case 3. A 59-year-old male with symptomatic diabetic peripheral neuropathy of eight years duration presented with 5/10 pain on the VAS. At baseline, the patient was taking 40 tablets of 5/325 oxycodone/acetaminophen per month as needed for pain. The patient used the WINS device intermittently for about two months and was non-adherent in using the device. A year later, the patient’s pain has increased from a 5 to a 6/10 and the patient now takes an increased dose of 10/325 oxycodone/acetaminophen to help with symptomatic relief.
Case 4. A 62-year-old female with chronic regional pain syndrome presented with 7/10 baseline pain on the VAS. The patient was symptomatic for four years with gradual worsening of symptoms. Her baseline treatment consisted of 450 mg of pregabalin (Lyrica, Pfizer) twice a day and 800 mg of gabapentin three times a day along with 5/325 oxycodone/acetaminophen for breakthrough pain. After one year of using the WINS device, the patient’s pain decreased from a 7 to a 6/10 while maintaining the same medication dosage.
Case 5. A 65-year-old male with diabetic peripheral neuropathy presented with 2/10 baseline pain on the VAS for six months. The patient was on the verge of taking gabapentin but felt symptom-free after using the WINS device. After one year, the patient’s pain decreased from a 2 to a 1/10 without the need for medications.
In Conclusion
Chronic pain affects millions of people in the United States. While randomized controlled trials are needed to truly assess the efficacy of the WINS device in alleviating pain, it may potentially be useful as part of the multimodal armamentarium strategy to help patients suffering from chronic pain.
Ms. Nanrhe is a second-year student at the Dr. William M. Scholl College of Podiatric Medicine at Rosalind Franklin University of Medicine and Science in Chicago. She is a National Institutes of Health (NIH) T35 funded research scholar and currently serves as an executive board member of the Illinois Podiatric Medical Student Association.
Dr. Wu is the Associate Dean of Research, a Professor of Surgery at the Dr. William M. Scholl College of Podiatric Medicine and a Professor of Stem Cell and Regenerative Medicine at the School of Graduate Medical Sciences at the Rosalind Franklin University of Medicine and Science. She is also the Director of the Center for Lower Extremity Ambulatory Research (CLEAR) in Chicago.
References
1. Mantyselka P, Ahonen R, Kumpusalo A, et al. Pain as a reason to visit the doctor: a study in Finnish primary health care. Pain. 2001; 89(2-3):175-80.
2. American Geriatrics Society Panel on the Pharmacological Management of Persistent Pain in Older Adults. Pharmacological management of persistent pain in older persons. Pain Med. 2009;10(6):1062-1083.
3. Loveland-Cherry C. Chapter 16. Prevention — Safety and Quality. In (Hughes RG, ed.) Patient Safety and Quality: an Evidence-Based Handbook for Nurses. Agency for Healthcare Research and Quality, Rockville, MD, 2008.
4. Turk DC. Clinical effectiveness and cost-effectiveness of treatments for patients with chronic pain. Clin J Pain. 2002;18(6):355-365.
5. Yawn BP, Wollan PC, Weingarten TN, Watson JC, Hooten WM, Melton LJ 3rd. The prevalence of neuropathic pain: clinical evaluation compared with screening tools in a community population. Pain Med. 2009;10(3):586-593.
6. Doth AH, Hansson PT, Jensen MP, Taylor RS. The burden of neuropathic pain : A systematic review and meta-analysis of health utilities. Pain. 2010;149(2):338-344.
7. Wells N, Pasero C, Mccaffery M. Chapter 17. Improving the Quality of Care Through Pain Assessment and Management. In (Hughes RG, ed.) Patient Safety and Quality: an Evidence-Based Handbook for Nurses. Agency for Healthcare Research and Quality, Rockville, MD, 2008.
8. Herr K. Pain in the older adult: an imperative across all health care settings. Pain Manag Nurs. 2010;11(2 Suppl):S1-S10.
9. Attal N, Cruccu G, Haanpaa M, et al. EFNS guidelines on pharmacological treatment of neuropathic pain. Eur J Neurol. 2006; 13(11):1153-1169.
10. Fishbain DA. Approaches to treatment decisions for psychiatric comorbidity in the management of the chronic pain patient. Med Clin North Am. 1999;83(3):737–60.
11. Abant İ, Health B, High S. Therapies in Pain Management. 2006;(Yavuz).
12. Ro L, Chang K. Neuropathic pain: mechanisms and treatments. Chang Gung Med J. 2005; 28(9):597-605.
13. Rakel A, Sluka KA. NIH Public Access. 2009;10(6):492-499.
14. Sun R-Q, Wang H-C, Wan Y, et al. Suppression of neuropathic pain by peripheral electrical stimulation in rats: μ-opioid receptor and NMDA receptor implicated. Exp Neurol. 2004;187(1):23-29.
15. Chen C-C, Johnson MI, McDonough S, Cramp F. The effect of transcutaneous electrical nerve stimulation on local and distal cutaneous blood flow following a prolonged heat stimulus in healthy subjects. Clin Physiol Funct Imaging. 2007;27(3):154-161.
16. Sluka KA, Walsh D. Transcutaneous electrical nerve stimulation: basic science mechanisms and clinical effectiveness. J Pain. 2003;4(3):109-121.
17. Johnson MI, Bjordal JM. Transcutaneous electrical nerve stimulation for the management of painful conditions: focus on neuropathic pain. Expert Rev Neurother. May 2011;11(5):735-753.18.
18. Bjordal JM, Johnson MI, Magnus J, Johnson MI, Elisabeth A. Transcutaneous electrical nerve stimulation (TENS) can reduce postoperative analgesic consumption. A meta-analysis with assessment of optimal treatment parameters for postoperative pain. Eur J Pain. 2003; 7(2):181–8.
19. Pivec R, Stokes M, Chitnis AS, Paulino CB, Harwin SF, Mont MA. Clinical and economic impact of TENS in patients with chronic low back pain: analysis of a nationwide database. Orthopedics. 2013;36(12):922-928.
20. Bennett MI, Hughes N, Johnson MI. Methodological quality in randomised controlled trials of transcutaneous electric nerve stimulation for pain: low fidelity may explain negative findings. Pain. 2011;152(6):1226-1232.
