Pain Management Series, Part Three: Interventional Therapies & New Horizons
As the field of pain management evolves, scientists and clinicians from various specialties and medical fields work towards ever improving our understanding of the mechanism of pain and how to counteract it to provide excellent pain control. We look for new innovative medications, devices, delivery systems and surgeries. We aim to achieve satisfactory analgesia (relief from pain) while limiting adverse effects from medications. We have only reached the tip of the iceberg. This post concludes the series on pain management exploration and will focus on interventional pain relief therapies and future advancements on the horizon.
Spinal Cord Stimulation
Spinal cord stimulation (SCS) is an innovative technology that addresses some of the most difficult pain problems experienced. Proven as an effective treatment option for many chronic sufferers, SCS is most often used for neuropathic pain, including spinal radiculopathies, diabetic peripheral neuropathies, post-laminectomy syndrome (residual pain after back surgery), and Complex Regional Pain Syndrome (CRPS).4 Neuropathic pain occurs when there is an injury, disease, or trauma to the central nervous system (spinal cord) or peripheral nervous system (any nerves outside the spinal column). Neuropathic pain symptoms can cause sharp, pricking, and/or stabbing pain. You may experience intense pain from a non-painful stimulus such as a light touch or a brush against the skin. You may also feel an exaggerated response to a painful stimulus. Spinal cord stimulation is an implanted device that transmits mild electrical impulses to the pain transmitting tracts on the spinal cord. The stimulation interrupts the message of feeling pain and substitutes it with a more pleasing sensation called paresthesia or “pleasant tingling”. Spinal cord stimulation is often used when other treatments have failed. Recent new technology is focused on rechargeable, multi-programmable generators and various electrical lead arrays and configurations to provide maximal stimulation coverage.
New Therapies on the Horizon
Deep Brain Stimulation (DBS)
The goal of deep brain stimulation and motor cortex stimulation is to restore function or relieve pain by stimulating neural activity through surgically implanted electrodes. DBS was developed in the 1980s principally to treat movement disorders associated with essential tremor (ET) and Parkinson’s disease (PD). Today, its applications include other types of movement disorders and certain non-motor syndromes and pain conditions. Currently, deep brain stimulation is being studied to treat central neuropathic pain syndromes like trigeminal autonomic cephalgia and cluster headaches.5
Transcranial Magnetic Stimulation (TMS)
Transcranial magnetic stimulation is a tool that has been used in a wide variety of neurological disorders, including experimental, diagnostic, and therapeutic purposes. The TMS procedure produces a magnetic field that traverses the skull relatively unimpeded and induces an electrical field that yields actual brain stimulation. Because TMS is noninvasive and painless, it can easily be performed on patients while they are awake. Repetitive TMS has been investigated as a potential therapy in patients with medically intractable neuropathic pain and migraine headaches.6
Fentanyl HCL Iontophoretic Transdermal System (Fentanyl ITS)
The use of patient-controlled analgesia (PCA) over the last few decades has resulted in vast improvement in management of postoperative pain control and patient satisfaction. PCA allows patients to self-administer pain medications according to their own personal requirements for pain relief. The common routes of administration for the PCA have been through the intravenous line or epidural catheter. Iontophoresis uses a low-intensity electric current to transport ionized drug molecules actively across the skin and into the systemic circulation. Iontophoretic drug delivery is more advantageous over passive transdermal administration as the drug delivery is strictly controlled by the application of electric current which offers precise control over the frequency of analgesic dosing with a non-invasive approach.7
4. Kemler MA, Barendse GA, van Kleef M, et al. Spinal cord stimulation in patients with chronic reflex sympathetic dystrophy. N Engl J Med. 2000;343(9):618–624.
5. Bittar RG, Kar-Purkayastha I, Owen SL, et al. Deep brain stimulation for pain relief: a meta-analysis. Journal of Clinical Neuroscience. 2005;12(5):515–519.
6. Leo RJ, and Latif T. Repetitive transcranial magnetic stimulation (rTMS) in experimentally induced and chronic neuropathic pain: a review. J Pain. 2007;8(6):453–459.
7. Power I. Fentanyl HCl iontophoretic transdermal system (ITS): clinical application of iontophoretic technology in the management of acute postoperative pain. British Journal of Anaesthesia. 2007;98(1):4–11.
Pain Management Series Part One: MedicationViews 16316
Pain Management Series Part 2: Procedures & InjectionsViews 13438