Rechargeable spinal cord stimulators for chronic pain (Research article)

Back pain relief – overview of neurostimulators
Spinal cord stimulators are battery-powered electronic devices enclosed in a small metal container that are surgically implanted under the patient’s skin in the low back area. They send low levels of electrical energy to nerve fibers with the goal of preventing pain signals from reaching the brain. Depending on the patient, the pain is to some degree replaced with a feeling that is often described as a tingling or warm sensation.

Rechargeable spinal cord stimulators are new devices that differ from conventional spinal cord stimulators in that the battery is rechargeable. When the battery in a non-rechargeable device runs low, patients need surgery to replace the stimulator’s batteries. Even though the operation is not a very complicated procedure, it is still surgery and may involve the risk of infection and post surgical pain that lasts several days. Most batteries for neurostimulators generally last three to five years, although extensive stimulation shortens the battery life span and replacements for certain patients may be required as often as every year. To address this, neurostimulators with rechargeable batteries are designed to reduce the need for repeat surgeries with the goal of improving the patient’s comfort and quality of life, and helping the patient return to his or her regular everyday activities, job and functional abilities.

Chronic pain management
Pain that lasts for a long time, usually for at least six months or more, is defined as chronic. As opposed to acute pain, chronic pain is not associated with ongoing tissue destruction. It is often the result of an injury, trauma (for example, a fall), disease or dysfunction of the central or peripheral nervous system. Very rarely can a single treatment or therapy relieve chronic back pain. When first line treatments are not successful in helping manage the pain (such as pain relief medication, chiropractic treatments, physical therapy, etc.), and if the back problem cannot be surgically corrected, physicians often refer their patients to pain management physicians. Specialists in pain management work with patients to create customized pain management treatment plans. Depending on the patient’s condition, the therapy may include one or a combination of pain medications, physical therapy and nerve blocks. If these therapies are unable to relieve chronic pain, more advanced treatments, such as spinal cord stimulation, may be recommended. Patients may qualify for a spinal cord stimulator depending on their diagnoses, their medical history, and type and severity of pain.

Spinal cord stimulators for chronic pain relief
Spinal cord stimulation is part of a broader class of treatment called neurostimulation or neuromodulation, a group of medical therapies that also includes peripheral nerve stimulation. Both types of neurostimulation or neuromodulation can use implanted devices to treat pain at its source. Spinal cord stimulators are designed to treat the following types of chronic pain:

• Neuropathic pain (or nerve pain, which involves damage to the nerves, and is often characterized as burning, severe shooting pain and/or numbness or tingling)

• Chronic pain resulting from failed back surgery syndrome

• Chronic pain from radiculopathy (e.g. sciatica, or pain that radiates along the sciatic nerve from impingement of a lumbar spinal nerve)

Spinal cord stimulators are not used to treat nociceptive pain (a type of pain which usually gets better with healing, and is often characterized as a deep aching, throbbing, gnawing or sore sensation). While it is not considered a cure for pain, the goal of spinal cord stimulation is to help patients return to a more normal lifestyle by significantly reducing chronic pain to a more manageable level.