412 - Spinal Cord Stimulator

| The Surgical Technologist | APRIL 2018 158 C H R O N I C P A I N According to the American Association of Neurological Sur- geons, chronic neuropathic pain is long-term pain that con- tinues beyond the usual recovery period or pain that accom- panies a chronic health condition. Pain that is not a result of an injury is considered pathological, and is therefore treated as a condition, not a symptom. Patients likely suffer from neuropathic pain when there is disease, injury or trauma to the spinal cord or peripheral nervous system. These patients have symptoms which may include stabbing or sharp pain in lower or upper extremities. They may feel a high degree of pain from a light touch, and they often have an elevated response to painful stimuli. Many sufferers of chronic pain have difficulty working, participating in physical activity or enjoying life. It is not uncommon for patients suffering from chronic pain to have a mild to severe addiction to painkill- ers. However, some patients significantly reduce their intake of opioid medications after they undergo surgery for a spi- nal cord stimulator. S P I N A L C O R D S T I M U L A T O R Known as “pacemakers for pain,” a SCS device is a surgi- cally implanted neurostimulation device placed under the patient’s skin. There are various types of SCS systems; how- ever, all have three components: • Lead wire with 8 to 32 electrodes to deliver electrical pulses to the spinal cord • Pulse generator or neurostimulator with a battery that creates the electrical pulses • Patient controller remote that turns the system on and off and allows the patient to adjust the stimulation set- tings (parameters set by the physician) The doctor or clinician also has a programmer device to adjust or modify the stimulation program in the pulse generator. The mechanism action in a SCS system is to mask pain signals before they reach the brain. The device components (lead wires) are implanted in the body to deliver electrical pulses to the spinal cord. The SCS sends a mild electric cur- rent to the patient’s spinal cord. The lead wire carries the current from the neurostimulator to the nerve fibers in the spinal cord. The SCS stimulates the nerves where the patient feels pain, most often in the lower extremities. Because the electrical pulses mask and modify the pain signal from reaching the brain, the patient experiences less pain. SCS systems may use a low-frequency current to replace pain sensation with a mild tingling feeling (paresthesia). Alterna- tively, some SCS systems use high-frequency or burst pulses to mask pain without a tingling sensation. It is important to note that spinal cord stimulators do not eliminate the source of the patient’s pain – rather, the SCS changes how the brain per- ceives the pain signal. I N D I C A T I O N S Patients are selected for SCS surgery if they have had lower back, leg or arm chronic pain for three months or more. In most cases, these patients had previ- ous spine surgery. The ideal patient for this procedure is in the early stage of a chronic pain condi- tion. SCS systems are implanted in patients to help reduce pain caused by: • Failed back surgery syndrome – failure of spine sur- gery to relieve leg pain, but not due to technical failure of the original procedure (hardware) or technique • Regional pain syndrome – nervous system disease in which patients feel progressively increased chronic burning pain, generally in the foot or hand • Chronic leg (sciatica) – persistent pain caused by nerve damage or from degenerative conditions such as arthritis or spinal stenosis • Cervical and lumbar radiculitis; neuropathy • Arachnoiditis – inflammation of the protective lining of the spinal nerves Patients may discuss SCS surgery as an alternative to a more complex spine surgery once they have had a successful spi- nal cord stimulator trial. Additional criteria for patients being considered for SCS include: pain not associated with malignancy, no pacemaker or other medical contraindica- tions, no major psychiatric disorders, no related litigation and the willingness to stop inappropriate drug use prior to implantation. If the trial spinal cord stimulator has success with at least a 50% reduction of the patient’s pain, surgery will be scheduled to permanently implant the SCS.