What causes pain?
Pain is a reaction to signals that are transmitted throughout the body. These signals are sent from the pain source, through the nerves in the spinal cord, to the brain, where they are perceived as pain. This is important because it means that pain can be controlled by preventing the pain signals from reaching the brain. If the pain signals never reach the brain, the pain is not experienced.
What is "chronic" or "intractable" pain and what causes it?
Chronic pain is pain that persists or recurs over a prolonged period of time (more than six months). If it is not adequately relieved by standard medical management, it is said to be intractable pain. Chronic pain may result from a previous injury long since healed, or it may have an ongoing cause, such as arthritis, cancer, nerve damage or chronic infection. Pain also can be due to conditions such as failed back syndrome and complex regional pain syndrome.
How common is chronic pain and what are its effects?
Increasingly, pain is being recognized as a major public health problem. In the United States, it is estimated that chronic pain affects 15 to 33 percent of the U.S. population.1 With chronic pain, normal lifestyles can be restricted or even impossible. Many people suffer from chronic pain, unaware that there are a variety of treatment options that can help them live more normal lives.
Chronic pain is a significant cause of disability, loss of productivity and healthcare spending in the United States. In fact, chronic pain disables more people than cancer or heart disease and costs the American public more than both diseases combined. Medical economists estimate that pain treatment costs $100 billion a year in medical costs, including 515 million lost work days and 40 million doctor visits.2
What are the treatments for chronic pain?
Physicians use numerous treatments to manage chronic pain. Their goal is to control pain while causing as few side effects as possible. Following are common chronic pain treatments:
Modifications - exercise, relaxation training, support groups.
Rehabilitation - physical therapy, massage, acupuncture.
Oral medications - mild pain relievers such as over-the-counter aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen, opiates such as codeine or morphine, and other types of drugs such as anti-depressants.
Corrective surgery - removing or modifying the condition causing pain.
Interventional therapies - APT spinal cord stimulation and APT intrathecal drug delivery both work directly on the spinal cord, the highway for pain signals, to interfere with pain signals before they reach the brain.
Neuroablative surgery - destruction of the actual nerves, or in some cases, a portion of the spinal cord carrying the pain signals.
What are the advanced pain therapies, spinal cord stimulation and intrathecal drug delivery?
Neurostimulation (including both spinal cord stimulation and peripheral nerve stimulation) uses a small neurostimulation system that is surgically placed under the skin to send mild electrical impulses to the spinal cord or specific nerve. The electrical impulses are delivered through a lead (a special medical wire) that is also implanted). These electrical impulses block the signal of pain from reaching the brain, thus providing relief for the patient. Spinal cord stimulation uses either a fully implantable neurostimulation system or an external radio frequency system. Peripheral nerve stimulation uses an external radio frequency system.
Intrathecal drug delivery systems use a small pump that is surgically placed under the skin of the abdomen to deliver medication directly through a small tube called a catheter that is also surgically placed. The spinal cord is like a highway for pain signals on the way to the brain, where the feeling of pain is experienced by the body. Because the medication is delivered to the spinal cord, where pain signals travel, APT intrathecal drug delivery system can often offer dramatic pain control, with only a tiny fraction of the dose that would be required with pills. This helps minimize side effects.
How effective are APT spinal cord stimulation and APT intrathecal drug delivery?
Although they cannot guarantee complete pain relief, both therapies have been proven to be effective. Literature study results show that 52 to 66 percent of patients receiving APT spinal cord stimulation therapy received good to excellent pain relief.3,4,5
Wtih APT intrathecal drug delivery, in a multicenter, retrospective study of 429 patients, 95 percent of the patients receiving the therapy reported an improvement in their overall rating of pain relief.6 Eighty-two percent of the patients reported an improvement in their activities of daily living.6
APT spinal cord stimulation and APT intrathecal drug delivery can be tested to determine whether they will be effective for a patient's particular pain. And, unlike other therapies, such as destroying certain nerves, both therapies can be discontinued at any time by turning off or removing the systems.
What are the risks associated with APT spinal cord stimulation and intrathecal drug delivery?
As with any medical treatment, patients should talk with their doctor about complications associated with APT spinal cord stimulation and intrathecal drug delivery.
With APT spinal cord stimulation, because the system is surgically placed, infections are possible. Other complications may include undesirable change in stimulation, lead migration and loss of pain relieving effect.
With APT intrathecal drug delivery, because the pump and catheter are surgically placed, infections are possible. The catheter could become dislodged or blocked, causing an interruption in pain relief. In rare cases, the pump could stop working, with the same result. Drug-related side effects also can occur. They may include itching, urinary retention and constipation.
When do physicians consider a patient for APT?
APT spinal cord stimulation and APT intrathecal drug delivery should be considered when:
- Non-interventional therapies have failed.
- Oral medications are not effective or cause intolerable side effects.
- Further corrective surgeries are unlikely to relieve the patient's pain.
- No untreated chemical dependency exists.
- Psychological clearance has been obtained.
- No contraindications to surgery are present (i.e., sepsis, coagulopathy).
- The screening test has been successful.
What types of physicians offer APT?
Anesthesiologists, neurosurgeons specializing in pain management and orthopedic surgeons are practitioners who use APT to treat chronic pain conditions.
How do APT spinal cord stimulation and APT intrathecal drug delivery affect a patient's daily life?
Both therapies can significantly reduce chronic pain. Patients are encouraged to lead an active lifestyle, which may include work and their usual activities of daily living. The devices themselves do not greatly limit patients. Their role is to significantly reduce the pain.
- Bonica, JJ. Importance of the problem. In: Anderson, S., Bond, M., Swedlow, M. eds. Chronic non-cancer pain. Lancaster, UK: MTP Press, 1987.
Business Week, "Conquering Pain: New discoveries and treatments offer hope. March 1, 1999.
- Turner J, Loeser J, Bell K. Spinal cord stimulation for chronic low back pain: a systematic literature synthesis. Neurosurgery, 1995; 37:1088-1096.
- North R, Kidd D, Zahurak M, et al. Spinal cord stimulation for chronic, intractable pain: experience over two decades. Neurosurgery, 1993; 32:384-395.
- Devulder J, De Laat M, Van Bastelaere M, et al. Spinal cord stimulation: a valuable treatment for chronic failed back surgery patients. J Pain Symptom Manage, 1997; 13:296-301.
- Paice JA, Penn RD, Shott S. Intraspinal morphine for chronic pain: a retrospective, multicenter study. J Pain Symptom Management. 1996;11(2):71-80.