lequebecfume
01-21-2009, 01:53 AM
January 19, 2009
Syndrome amplifies pain signals to brain
By DR. YONG H. TSAI
MANAGING PAIN
Do you live with constant pain but are told that everything is normal? Do you have fibromyalgia, chronic myofascial pain, tension headache, migraine or irritable bowel syndrome and feel there is no answer in sight? You may have CSS (central sensitivity syndrome).
CSS occurs when the central nerve system (brain and spinal cord) becomes hypersensitivity to stimulus. Patients with CSS experience an exaggerated response to painful stimulus (hyperalgesia), prolonged length of response after brief stimulus (persistent and widespread pain), pain after the simple act of touching or rubbing due to a reduction of pain threshold (allodynia).
At normal condition, when injury, disease, or inflammation occurs, pain receptors in our skin, muscles, ligaments and joints are able to detect tissue damage. In turn, numerous neurotransmitters, located in each nerve cell, work together and transmit electrical impulses from the pain receptor to the peripheral nerve and up the spinal cord. Finally, these impulses are relayed to the brain, whose role is to process and interpret pain signals.
During an injury, you would experience acute pain because of tissue damage or inflammation. Fortunately, acute pain usually resolves itself in a matter of time, depending on the severity of the injury or illness. Further characteristics of acute pain are the fact that you know exactly from where the pain stems and its course is usually predictable. That is the reason that we have always viewed the nervous system as being "hard wired" -- that is stimulation of a nerve ending (say a needle prick) always produces the same response by traveling along the nerves to the brain to produce the pain sensation of skin being pierced. However, it is now understood that this concept cannot be applied in chronic pain.
When the brain receives repetitive and sustained electrical impulses from the pain receptors such as repetitive injuries or chronic inflammation for a prolonged period of time, it becomes hypersensitive and its pain signals are amplified. Moreover, pain signals become automatically relayed, even in the absence of electrical impulses. Even though the original injury may be healed, the sensation of pain can persist and even intensify.
A typical example of abnormal pain processing is fibromyalgia and chronic myofascial pain syndrome. Patients with fibromyalgia suffer with chronic widespread, generalized muscle pain, along with headaches, irritable bowel syndrome, chronic fatigue, hyperalgesia, allodynia and persistent pain, but lack tissue damage or inflammation.
The new concepts of central hypersensitivity and central sensitivity syndrome offer a good direction for future research of related syndromes. Currently, we have adequate scientific evidences that central hypersensitivity is mainly caused by imbalance of neurotransmitters. Hopefully, with further understanding of pain processing, we can develop some medications specially targeting the problems of central hypersensitivity and fibromyalgia.
Dr. Yong H. Tsai is board-certified in rheumatology, allergy and clinical immunology and has been practicing in this area since 1993. Send questions to Dr. Tsai in care of accent@news-jrnl.com. You also can check his Web site: arthritis-allergy.net.
http://www.news-journalonline.com/NewsJournalOnline/Opinion/Columnists/Pain/colPAIN011909.htm
Syndrome amplifies pain signals to brain
By DR. YONG H. TSAI
MANAGING PAIN
Do you live with constant pain but are told that everything is normal? Do you have fibromyalgia, chronic myofascial pain, tension headache, migraine or irritable bowel syndrome and feel there is no answer in sight? You may have CSS (central sensitivity syndrome).
CSS occurs when the central nerve system (brain and spinal cord) becomes hypersensitivity to stimulus. Patients with CSS experience an exaggerated response to painful stimulus (hyperalgesia), prolonged length of response after brief stimulus (persistent and widespread pain), pain after the simple act of touching or rubbing due to a reduction of pain threshold (allodynia).
At normal condition, when injury, disease, or inflammation occurs, pain receptors in our skin, muscles, ligaments and joints are able to detect tissue damage. In turn, numerous neurotransmitters, located in each nerve cell, work together and transmit electrical impulses from the pain receptor to the peripheral nerve and up the spinal cord. Finally, these impulses are relayed to the brain, whose role is to process and interpret pain signals.
During an injury, you would experience acute pain because of tissue damage or inflammation. Fortunately, acute pain usually resolves itself in a matter of time, depending on the severity of the injury or illness. Further characteristics of acute pain are the fact that you know exactly from where the pain stems and its course is usually predictable. That is the reason that we have always viewed the nervous system as being "hard wired" -- that is stimulation of a nerve ending (say a needle prick) always produces the same response by traveling along the nerves to the brain to produce the pain sensation of skin being pierced. However, it is now understood that this concept cannot be applied in chronic pain.
When the brain receives repetitive and sustained electrical impulses from the pain receptors such as repetitive injuries or chronic inflammation for a prolonged period of time, it becomes hypersensitive and its pain signals are amplified. Moreover, pain signals become automatically relayed, even in the absence of electrical impulses. Even though the original injury may be healed, the sensation of pain can persist and even intensify.
A typical example of abnormal pain processing is fibromyalgia and chronic myofascial pain syndrome. Patients with fibromyalgia suffer with chronic widespread, generalized muscle pain, along with headaches, irritable bowel syndrome, chronic fatigue, hyperalgesia, allodynia and persistent pain, but lack tissue damage or inflammation.
The new concepts of central hypersensitivity and central sensitivity syndrome offer a good direction for future research of related syndromes. Currently, we have adequate scientific evidences that central hypersensitivity is mainly caused by imbalance of neurotransmitters. Hopefully, with further understanding of pain processing, we can develop some medications specially targeting the problems of central hypersensitivity and fibromyalgia.
Dr. Yong H. Tsai is board-certified in rheumatology, allergy and clinical immunology and has been practicing in this area since 1993. Send questions to Dr. Tsai in care of accent@news-jrnl.com. You also can check his Web site: arthritis-allergy.net.
http://www.news-journalonline.com/NewsJournalOnline/Opinion/Columnists/Pain/colPAIN011909.htm