Central Sensitisation and chronic pain
Central sensitisation is a process that occurs in the central nervous system (CNS) in response to chronic or persistent pain. It is characterized by an increased sensitivity to pain, a decrease in the threshold for pain, and an increased spread of pain to areas that were not previously affected.
The International Association for the Study of Pain (IASP) defines Central Sensitisation as
Increased responsiveness of nociceptive neurons in the central nervous system to their normal or subthreshold afferent input.
Note: See note for sensitization and nociceptive neuron above. This may include increased responsiveness due to dysfunction of endogenous pain control systems. Peripheral neurons are functioning normally; changes in function occur in central neurons only.https://www.iasp-pain.org/resources/terminology/
What causes Central Sensitisation?
Central sensitization is thought to be caused by a number of factors, including injury, inflammation, and nerve damage. When these factors are present, they can lead to changes in the sensitivity of nerve cells in the spinal cord and brain. These changes can result in an increased sensitivity to pain, as well as an increased response to pain stimuli.
Central sensitization can also be triggered by persistent pain and emotional distress, leading to a process called maladaptive plasticity, where the nervous system becomes more sensitive to pain, and pain becomes more intense and widespread.
Central Sensitisation and Chronic Primary Pain
Central sensitization can lead to chronic primary pain, which is defined as pain that persists for more than three months where no underlying structural cause for the pain can be found. This is also called nociplastic pain. In addition to causing pain, it can also lead to a number of other symptoms, including fatigue, sleep disturbance, and emotional distress.
Central Sensitisation and Chronic Secondary Pain
Central sensitisation can also be a feature in chronic secondary pain, that is, pain that is a symptom of disease process. Sometimes, but not always, central sensitisation can play a role in chronic secondary pain. Sometomes diseases like Rheumatoid Arthritis, Ehlers Danlos, osteoarthrits, etc, can have an element of central sensitisation, but this should never be assumed. Chronic pain is individual, and each person needs to be assessed individually.
Treatments for Central Sensitisation
Treatments for central sensitization typically involve addressing the underlying cause of the pain and trying to calm the over sensitization of the central nervous system. This can include physical therapy, medications, psychological therapy, and other pain management strategies.