Nociplastic chronic neck pain: From mechanisms to physical therapy clinical practice

Table 2 Comparison between nociplastic pain and central sensitization

	Nociplastic pain	Central sensitization
What it is	A pain category in which the predominant mechanism of transmission and maintenance relates to altered processing and regulation of nociceptive information by the nervous system, without adequate explanation from dominant tissue damage or documented somatosensory disease	A neurophysiological phenomenon of increased amplification or reduced inhibition of pain signals within the central nervous system, producing enhanced sensitivity to stimuli
Indicative findings (non-specific, non-diagnostic)	Altered modulation of pain; enhanced response to sensory stimuli; reduced descending inhibition; widespread or variable pain distribution; diffuse pressure hypersensitivity; attenuated exercise-induced hypoalgesia; sensorimotor disturbances. May include central sensitization phenomena but is not limited to them	Increased spinal neuron excitability; temporal summation; hyperalgesia; allodynia; expanded receptive fields; and reduced descending inhibition. May contribute to nociplastic pain but does not itself constitute a pain category
Is it a pain category?	Yes, a category based on the predominant mechanism	No, a functional phenomenon, not a diagnosis
Coexistence with other mechanisms?	Frequently coexists with nociceptive or neuropathic features	Can occur across different pain categories
Relationship between the two	May include central sensitization phenomena	Is not equivalent to the nociplastic pain category
Ref.	Treede et al[6], 2019; Kosek et al[7], 2021; Raja et al[9], 2020; Kosek et al[10], 2016

Nociplastic pain is a pain category based on the predominant mechanism of transmission and maintenance, as defined by the International Association for the Study of Pain. Central sensitization is a neurophysiological phenomenon of increased facilitation or reduced inhibitory regulation that can be observed across pain categories. The findings listed are indicative and non-specific and do not constitute diagnostic criteria.