Tools
Nerve Stimulation
Introduction
The concept of nerve stimulation/peripheral nerve stimulation (PNS) is not new and has been in practice since the early 19 century. However, clinical studies were done much later in this field. In 1976, Campbell et al. published the reports of the first set of clinical studies done in the field of pain management using PNS.[1] Since then, PNS has been actively explored as a treatment of modality for managing chronic pain conditions. Chronic pain conditions, including low back pain, neck pain, and neuropathic pain states like chronic regional pain syndrome, causalgia, and diabetic neuropathy, afflict a large group of population. They pose a substantial economic burden on society.[2][3] These pain conditions are the leading cause of disability in the world.[4] Currently, there is an active opioid crisis in the United States, with over 15,000 deaths involving prescription opioids reported in 2015. Also, managing these chronic pain conditions with conventional medical management can lead to multiple drug-drug interactions resulting in intolerable side effects.[5] PNS offers a relatively safe and effective treatment modality in the treatment of such chronic pain conditions.
Anatomy and Physiology
Register For Free And Read The Full Article
Search engine and full access to all medical articles- 10 free questions in your specialty
- Free CME/CE Activities
- Free daily question in your email
- Save favorite articles to your dashboard
- Emails offering discounts
Learn more about a Subscription to StatPearls Point-of-Care
Anatomy and Physiology
The determination of the nerve to be stimulated corresponds with the area where the pain relief is required. Any focal area of pain in the body can be managed by stimulation of the peripheral nerve supplying that particular dermatome. Nerve stimulation is broadly divided into electrical nerve stimulation and magnetic nerve stimulation.
Electrical Nerve Stimulation
The mechanism of electrical nerve stimulation is not fully understood, but the idea originates from the "gate control theory."[6] The most simplistic explanation of this theory is that electrical stimulus is applied to the A-beta fibers (that carry non-painful stimuli) in the peripheral nerve, which blocks the impulses carried in C fibers (carry painful stimuli). Stimulation of the A-beta fibers in the vicinity of C-fibers can result in the closure of the "gate" that exists in the dorsal horn of the spinal cord and thus result in the blockade of painful stimuli. Another mechanism that has been proposed includes inhibition of wide dynamic range hyperexcitability through GABA release.[7] While some evidence points to the pain relief secondary to the stimulation-induced release of serotonin, adenosine, and noradrenaline.[8]
Magnetic Nerve Stimulation
A magnetic stimulator is not an implantable device and works by a different mechanism compared to an electrical nerve stimulator. The transcranial magnetic stimulator is a commonly used application of this technology. It consists of a capacitor that may be able to discharge current through a hand-held wire coil, which then produces a magnetic field lasting 100 to 200 microseconds. When held against the skull, this magnetic field can produce depolarization of cortical neurons. The following mechanisms have been proposed for the therapeutic effects of transcranial magnetic stimulation.[9]
- Changes in brain monoamines
- Changes in cerebral blood flow
- Reduction of oxidative stress to neurons
For the purpose of this article, we will be describing implantable electric peripheral nerve stimulators in detail in the upcoming sections.
Indications
PNS limits the amount of energy by using focalized current and has been used to treat a variety of chronic pain disorders.[10] Prior studies have shown good outcomes from PNS on the median, ulnar, sciatic, ilioinguinal, and genitofemoral nerves.[11][12][13][14] Weiner et al. placed the first percutaneous PNS lead to manage occipital neuralgia.[15] Schoenen et al. published the results of a multicenter study evaluating the efficacy of sphenopalatine ganglion (SPG) stimulation in the treatment of cluster headaches.[16] The authors reported that 67% of subjects achieved pain relief, and 36% of patients achieved a reduction in attack frequency. Saper et al. published the results of the first randomized study on the use of occipital nerve stimulation (ONS) for the treatment of migraine.[17] 39% of patients in the study showed a 50% or greater reduction in the number of headache days per month. It may also be effective in other headache disorders.[18][19] PNS is also efficacious in treating sacroiliac joint pain.[20] Improvements were noted during the 12-month follow-up in the study, in International Patient Satisfaction Index (IPSI), Visual analog scale (VAS), and Oswestry Disability Index 2.0 (ODI). PNS is also efficacious in the treatment of shoulder pain secondary to subacromial impingement syndrome. The study reported improvements in pain and functionality.[21]
Recently results of a study evaluating the use of PNS in the treatment of low back pain were reported. PNS was used to stimulate the medial branches of the dorsal ramus for 30 days, and after that, the leads were explanted.[22] Subjects reported statistically significant reductions in the average pain intensity (ANOVA, p<0.005) and worst pain intensity (ANOVA, p<0.001) scores at the end of the trial (EOT). They continued to experience benefit at the 4-month follow-up period, and the mean reduction in average pain intensity and worst pain intensity was 84% and 78%, respectively. At 12-month follow-up, responders showed a 63% reduction in pain intensity and a 32-point decrease in disability scores.[23]
There have also been reports of the effectiveness of Gasserian ganglion stimulation in the treatment of post-stroke facial pain.[24]
Contraindications
One of the main contraindications to performing this procedure is the presence of local infection at the site of stimulator lead placement. Performing this procedure in patients with active bleeding disorder requires extra caution as it can lead to hematoma formation.
Equipment
PNS requires the availability of a nerve stimulation kit that usually includes a transducer needle and a stimulation electrode. After the patient is prepped under sterile conditions using a chlorhexidine/iodine solution, a sterile drape is used to cover the area of surgery. We identify the desired location of needle entry and administer local anesthesia. The target nerve is identified with the help of ultrasound guidance. A transducer needle is used to access the target nerve. The ideal target of stimulation is approximately 1 cm away from the target nerve. A PNS electrode is introduced through the transducer needle and is ideally set parallel to the nerve. The battery source is connected to the proximal end of the electrode. Once a connection is established, the electrode is tested intraoperatively to assess the distribution of paresthesia. If the paresthesia corresponds to the area of pain, the electrode is tunneled under the skin and secured in place using a suture.
This procedure is also performed by the direct exploration of the nerve where a surgeon (usually a neurosurgeon) dissects the area surrounding the nerve and places the electrode on top of the nerve.
Recently, surgeons have directed focus on using wireless nerve stimulation devices that preclude the use of an implantable pulse generator. These wireless devices use an implantable electrode that has inbuilt microelectrodes, which are stimulated by an external source generator, usually in the form of a patch or wearable device. In the United States, the Food and Drug Administration has approved 4 devices for wireless peripheral nerve stimulation.
Personnel
Typically neurosurgeons, anesthesiologists trained in interventional pain medicine, and interventional radiologists perform peripheral nerve stimulator implantation. It is advised that physicians must have performed this procedure an adequate number of times under supervision before performing it independently.
Complications
Like any other invasive procedure, common complications include infection, bleeding/hematoma formation, surgical site pain, and nerve injury.
Device-related complications include migration of the stimulator lead, lead fracture, and device malfunction.[10][25] Even though these complications are minor, but require a minor revision of the procedure for the re-implantation of the stimulator lead.
Clinical Significance
Chronic pain is one of the most prevalent health problems and poses a considerable burden on the economy and society. Amid the current opioid crisis, there is a need for the exploration of alternative pain therapies. Peripheral nerve stimulation offers a relatively safe option for the management of such painful pain conditions. The use of peripheral nerve stimulation can provide regional anesthesia without exposing the patient to the systemic side effects of opioid medications. Since these procedures are minimally invasive, they offer an alternative for patients who are not candidates for major joint replacement surgeries secondary to contraindication to general anesthesia.
Enhancing Healthcare Team Outcomes
For the success of this therapy, the physician performing PNS must be adequately trained in the procedure. A prior discussion is vital with the patient explaining all the risks and benefits of the procedure. A realistic expectation needs to be set with the patient about the outcomes of the therapy regarding his/her pain relief. PNS is best treated by an interprofessional team which may consist of primary care providers, neurologists, anesthesiologists, specialty pain and neuroscience nurses, and pharmacists.
There is a need for more randomized controlled trials to assess this novel therapy's full potential completely.
References
Campbell JN, Long DM. Peripheral nerve stimulation in the treatment of intractable pain. Journal of neurosurgery. 1976 Dec:45(6):692-9 [PubMed PMID: 1086348]
Deer TR, Jain S, Hunter C, Chakravarthy K. Neurostimulation for Intractable Chronic Pain. Brain sciences. 2019 Jan 24:9(2):. doi: 10.3390/brainsci9020023. Epub 2019 Jan 24 [PubMed PMID: 30682776]
Jain S, Malinowski M, Chopra P, Varshney V, Deer TR. Intrathecal drug delivery for pain management: recent advances and future developments. Expert opinion on drug delivery. 2019 Aug:16(8):815-822. doi: 10.1080/17425247.2019.1642870. Epub 2019 Jul 19 [PubMed PMID: 31305165]
Level 3 (low-level) evidenceGBD 2016 Disease and Injury Incidence and Prevalence Collaborators. Global, regional, and national incidence, prevalence, and years lived with disability for 328 diseases and injuries for 195 countries, 1990-2016: a systematic analysis for the Global Burden of Disease Study 2016. Lancet (London, England). 2017 Sep 16:390(10100):1211-1259. doi: 10.1016/S0140-6736(17)32154-2. Epub [PubMed PMID: 28919117]
Level 1 (high-level) evidenceJain S, Yuan H, Spare N, Silberstein SD. Erenumab in the treatment of migraine. Pain management. 2018 Nov 1:8(6):415-426. doi: 10.2217/pmt-2018-0037. Epub 2018 Sep 21 [PubMed PMID: 30235976]
Melzack R, Wall PD. Pain mechanisms: a new theory. Science (New York, N.Y.). 1965 Nov 19:150(3699):971-9 [PubMed PMID: 5320816]
Level 3 (low-level) evidenceCui JG, O'Connor WT, Ungerstedt U, Linderoth B, Meyerson BA. Spinal cord stimulation attenuates augmented dorsal horn release of excitatory amino acids in mononeuropathy via a GABAergic mechanism. Pain. 1997 Oct:73(1):87-95 [PubMed PMID: 9414060]
Level 3 (low-level) evidenceLinderoth B, Gazelius B, Franck J, Brodin E. Dorsal column stimulation induces release of serotonin and substance P in the cat dorsal horn. Neurosurgery. 1992 Aug:31(2):289-96; discussion 296-7 [PubMed PMID: 1381066]
Level 3 (low-level) evidenceMerton PA, Morton HB. Stimulation of the cerebral cortex in the intact human subject. Nature. 1980 May 22:285(5762):227 [PubMed PMID: 7374773]
Deer TR, Grider JS, Lamer TJ, Pope JE, Falowski S, Hunter CW, Provenzano DA, Slavin KV, Russo M, Carayannopoulos A, Shah JM, Harned ME, Hagedorn JM, Bolash RB, Arle JE, Kapural L, Amirdelfan K, Jain S, Liem L, Carlson JD, Malinowski MN, Bendel M, Yang A, Aiyer R, Valimahomed A, Antony A, Craig J, Fishman MA, Al-Kaisy AA, Christelis N, Rosenquist RW, Levy RM, Mekhail N. A Systematic Literature Review of Spine Neurostimulation Therapies for the Treatment of Pain. Pain medicine (Malden, Mass.). 2020 Nov 7:21(7):1421-1432. doi: 10.1093/pm/pnz353. Epub [PubMed PMID: 32034422]
Level 1 (high-level) evidenceStinson LW Jr, Roderer GT, Cross NE, Davis BE. Peripheral Subcutaneous Electrostimulation for Control of Intractable Post-operative Inguinal Pain: A Case Report Series. Neuromodulation : journal of the International Neuromodulation Society. 2001 Jul:4(3):99-104. doi: 10.1046/j.1525-1403.2001.00099.x. Epub [PubMed PMID: 22151653]
Level 3 (low-level) evidencevan Balken MR, Vandoninck V, Messelink BJ, Vergunst H, Heesakkers JP, Debruyne FM, Bemelmans BL. Percutaneous tibial nerve stimulation as neuromodulative treatment of chronic pelvic pain. European urology. 2003 Feb:43(2):158-63; discussion 163 [PubMed PMID: 12565774]
Barolat G. Percutaneous retroperitoneal stimulation of the sacral plexus. Initial report and technical note. Stereotactic and functional neurosurgery. 1991:56(4):250-7 [PubMed PMID: 1808649]
Level 3 (low-level) evidenceAl Khalili Y, Jain S, Lam JC, DeCastro A. Brachial Neuritis. StatPearls. 2023 Jan:(): [PubMed PMID: 29763017]
Weiner RL, Reed KL. Peripheral neurostimulation for control of intractable occipital neuralgia. Neuromodulation : journal of the International Neuromodulation Society. 1999 Jul:2(3):217-21. doi: 10.1046/j.1525-1403.1999.00217.x. Epub [PubMed PMID: 22151211]
Schoenen J, Jensen RH, Lantéri-Minet M, Láinez MJ, Gaul C, Goodman AM, Caparso A, May A. Stimulation of the sphenopalatine ganglion (SPG) for cluster headache treatment. Pathway CH-1: a randomized, sham-controlled study. Cephalalgia : an international journal of headache. 2013 Jul:33(10):816-30. doi: 10.1177/0333102412473667. Epub 2013 Jan 11 [PubMed PMID: 23314784]
Level 1 (high-level) evidenceSaper JR, Dodick DW, Silberstein SD, McCarville S, Sun M, Goadsby PJ, ONSTIM Investigators. Occipital nerve stimulation for the treatment of intractable chronic migraine headache: ONSTIM feasibility study. Cephalalgia : an international journal of headache. 2011 Feb:31(3):271-85. doi: 10.1177/0333102410381142. Epub 2010 Sep 22 [PubMed PMID: 20861241]
Level 1 (high-level) evidenceAl Khalili Y, Ly N, Murphy PB. Cervicogenic Headache. StatPearls. 2023 Jan:(): [PubMed PMID: 29939639]
Jain S, Silberstein SD. Invited Commentary on Preventive Anti-Migraine Therapy (PAMT). Current treatment options in neurology. 2019 Mar 14:21(4):14. doi: 10.1007/s11940-019-0555-4. Epub 2019 Mar 14 [PubMed PMID: 30868470]
Level 3 (low-level) evidenceGuentchev M, Preuss C, Rink R, Peter L, Wocker EL, Tuettenberg J. Technical Note: Treatment of Sacroiliac Joint Pain with Peripheral Nerve Stimulation. Neuromodulation : journal of the International Neuromodulation Society. 2015 Jul:18(5):392-6. doi: 10.1111/ner.12255. Epub 2014 Oct 29 [PubMed PMID: 25354279]
Wilson RD, Harris MA, Gunzler DD, Bennett ME, Chae J. Percutaneous peripheral nerve stimulation for chronic pain in subacromial impingement syndrome: a case series. Neuromodulation : journal of the International Neuromodulation Society. 2014 Dec:17(8):771-6; discussion 776. doi: 10.1111/ner.12152. Epub 2014 Feb 11 [PubMed PMID: 24512114]
Level 3 (low-level) evidenceGilmore CA, Kapural L, McGee MJ, Boggs JW. Percutaneous Peripheral Nerve Stimulation (PNS) for the Treatment of Chronic Low Back Pain Provides Sustained Relief. Neuromodulation : journal of the International Neuromodulation Society. 2019 Jul:22(5):615-620. doi: 10.1111/ner.12854. Epub 2018 Oct 3 [PubMed PMID: 30284338]
Gilmore CA, Kapural L, McGee MJ, Boggs JW. Percutaneous Peripheral Nerve Stimulation for Chronic Low Back Pain: Prospective Case Series With 1 Year of Sustained Relief Following Short-Term Implant. Pain practice : the official journal of World Institute of Pain. 2020 Mar:20(3):310-320. doi: 10.1111/papr.12856. Epub 2019 Dec 2 [PubMed PMID: 31693791]
Level 2 (mid-level) evidenceTaub E, Munz M, Tasker RR. Chronic electrical stimulation of the gasserian ganglion for the relief of pain in a series of 34 patients. Journal of neurosurgery. 1997 Feb:86(2):197-202 [PubMed PMID: 9010419]
Level 2 (mid-level) evidenceJain S, Fishman MA, Wu C. Significant cephalad lead migration with use of externally powered spinal cord stimulator. BMJ case reports. 2018 Sep 21:2018():. pii: bcr-2018-225813. doi: 10.1136/bcr-2018-225813. Epub 2018 Sep 21 [PubMed PMID: 30244224]
Level 3 (low-level) evidence