Central Sensitisation

Key Points:

1. Central sensitisation is defined as “Increased responsiveness of nociceptive neurons in the central nervous system to their normal or subthreshold afferent input”.

2. Treatment options should be targeted and matched to the specific pain phenotypes.

Central sensitisation is a medical term frequently coined by pain specialist. However, most people have little understanding what it means to them. This is a summary from the published article, “Central sensitisation in chronic pain conditions: latest discoveries and their potential for precision medicine”  from Lancet Rheumatology March 30, 2021.

Sometimes, there are discrepancy between the peripheral sources of pain, the intensity of pain, and the disability associated with the pain. Often, the degree of tissue damage, inflammation, trauma does not suffice to explain the symptoms. In the recent years, neuroscience research has help us to understand the pathophysiology of pain, such as neuroplasticity, central nocicpetive signalling processing, etc. Central sensitisation provides an alternative explanation to this phenomena. 

The International Association for the Study of Pain (IASP) defined central sensitisation as “Increased responsiveness of nociceptive neurons in the central nervous system to their normal or subthreshold afferent input”. 

Treatment Options

Treatment reduce peripheral nocicpetion (bottom-up treatments) can potentially attenuate central sensitisation. Patients showing high amounts of central sensitisation before surgery are at higher risk of poor surgical outcomes and require approaches to attenuate central sensitisation (top-down treatment). In some patients, central sensitisation can be maintained by peripheral input (bottom–up), and surgical removal of the source of this input normalises these patients’ pain processing. 

It is also important to highlight that there are other factors, such as pain catastrophising, that interact with central sensitisation to determine whether a postoperative outcome is positive or not. Also, the presence of central sensitisation should not prevent health­care providers from searching for and possibly treating peripheral dysfunctions, in the context of a multifactorial disease model that considers both peripheral and central components. 

Among available and established pharmacological treat­ments, antidepressants are effective in different chronic musculoskeletal pain conditions associated with central sensitisation, such as fibromyalgia, low back pain, neck pain, and knee osteoarthritis. 

Opioids might reduce indices of central sensitisation in the short term (ie, 7·5 h after medication intake), their prolonged use (ie, for months) can lead to enhanced central sensitisation and related hyperalgesia. Therefore, current knowledge does not support the use of opioids to treat central sensitisation and suggests that long­term use of opioids might worsen the condition of patients with established central sensitisation. 

Physical therapy and Exercise produces a hypoalgesic effect and has the potential to reduce central sensitisation. Randomised trials have established the efficacy of psychological treatments for reducing chronic pain, and there is evidence that this effect might be mediated by mechanisms other than an effect on central sensitisation 

Talk to your pain specialist today to see if your pain is related to nervous system overdrive! 

Reference: 

J Nijs, SZ George, DJ Clauw. Central sensitisation in chronic pain conditions: latest discoveries and their potential for precision medicine. The Lancet Rheumatology. March 30, 2021. DOI:https://doi.org/10.1016/S2665-9913(21)00032-1