May 21, 2006 Chronic Pain Chronic pain is a type of pain that persists for at least a month, or well beyond the normal expected recovery time. The American Pain Foundation estimates about 50 million Americans are living with chronic pain. One of the most common types of chronic pain is back pain, which affects two-thirds of Americans at some point in their lives. Some other important causes of chronic pain include: arthritis, cancer, headache, trigeminal neuralgia and shingles. Chronic pain can have a big impact on a persons quality of life. A survey by the American Chronic Pain Association found 76 percent of survey respondents reported having daily pain. For 48 percent the pain doesnt ever go away. Pain can interfere with the ability to sleep, eat a balanced diet, participate in physical activity or work. The day-to-day need to cope with symptoms can lead to depression and irritability. Pinpointing the Cause of Chronic Pain It can be difficult to locate the cause of chronic pain. For example, research shows doctors are unable to find the cause of symptoms in 90 percent of patients with chronic low back pain. X-rays, MRIs and CT scans cant always find any type of injury or abnormality. And sometimes when a problem is identified and treated, pain still persists. Norman Marcus, M.D., Pain Medicine Specialist, at NYU Medical Center and Director of the Norman Marcus Pain Institute, says the cause of symptoms cant be identified in 70 to 80 percent of patients with chronic pain. That makes it difficult to find effective treatments. He developed a device to electrically stimulate a muscle, causing the muscle to contract. If the muscle is a source of pain, the patient will feel an obvious twitch of pain. The instrument is called a "Muscle Pain Detection Device." Marcus device was large and cumbersome. For practical purposes, he needed a smaller sized version that could be portable enough for health care workers to carry in a pocket. He turned to the senior Biomedical Engineering students at the Stevens Institute of Technology for help. As part of a class project, the students developed a hand-held device that is passed over the skin. A small electrical signal is used to stimulate the target muscles. The problem area is found when the patient experiences a painful twitch in response to the muscle stimulation. In many cases, once the cause of the problem is properly identified, patients can be treated with physical therapy and exercises. The students formed a company with Dr. Marcus, called SPOC (Stevens Proof of Concept) in hopes of eventually marketing their new device. Researchers have just started clinical trials to verify the effectiveness of the device. AUDIENCE INQUIRY Normal Marcus Pain Institute, http://www.backpainusa.com Stevens Institute of Technology, http://www.stevens.edu For general information on pain: American Chronic Pain Association, http://www.theapca.org American Pain Foundation, http://www.painfoundation.org The National Foundation for the Treatment of Pain, http://www.paincare.org National Institute for Neurological Disorders and Stroke, http://www.ninds.nih.gov BIBLIOGRAPHY "Americans Living with Chronic Pain Survey," Bethesda: American Chronic Pain Association/Roper Public Affairs and Media, downloaded from website (http://www.theapca.org), April 20, 2006. Arokosi, Jari, D.M.Sc., et al., "Activation of Lumbar Paraspinal and Abdominal Muscles During Therapeutic Exercises in Chronic Low Back Pain," Archives of Physical Medicine and Rehabilitation, May 2004, Vol. 85, No. 823-832. 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