Comparing Central Pain Processing in Individuals With Non-Traumatic Neck Pain and Healthy Individuals: A Systematic Review and Meta-Analysis

Abstract

This systematic review and meta-analysis examined the evidence for altered central pain processing in people with non-traumatic neck pain and the relationship between central pain processing, demographics and pain-related characteristics. Case-control studies reporting measures of altered central pain processing using quantitative sensory testing were reviewed. Standardized mean differences (SMDs) and 95% confidence intervals (CIs) between people with non-traumatic neck pain and controls were calculated. Meta-analysis was performed using random-effects models when appropriate. Associations between SMDs with demographics and pain-related characteristics were explored on a study level using meta-regression. Twenty-six studies were eligible with 25 included for meta-analysis. Meta-analysis demonstrated mechanical hyperalgesia at remote non-painful sites in the full sample [sample size (n)=1305, SMD=-0.68] and in the subgroup with moderate/severe disability [n=165, SMD=-0.86] (moderate-quality evidence). Meta-regression indicated that remote mechanical hyperalgesia was negatively associated with age (R 2 =25.4%, P=0.031). Very-low-to low-quality evidence of remote cold and heat hyperalgesia and dysfunctional conditioned pain modulation were identified. This review suggests that altered central pain processing is present in people with non-traumatic neck pain and may be associated with disability levels and age.

Profiling and Association over Time between Disability and Pain Features in Patients with Chronic Nonspecific Neck Pain: A Longitudinal Study

“…Those with radiating neck-arm pain show reduced heat pain thresholds at distant sites from the primary site of injury [ 11 ]. High pain sensitivity at distant sites from the painful region has also been found by a recent metanalysis in individuals with nontraumatic neck pain [ 12 ]. These results are indicative of altered central pain processing in these populations.…”

Central sensitisation in chronic pain conditions: latest discoveries and their potential for precision medicine

“…QST mea sures of hyperalgesia in the painful body region are not clear indicators of central sensitisation because they can also reflect peripheral sensitisation; however increased sensitivity to sensory input in nonpainful and healthy body parts is generally accepted as a sign of central sensitisation. Interpretation of QST findings in individual patients has to take into account characteristics such as sex, age, ethnic or racial status, and body site of measurement-all of which have been shown by epidemiological studies 61,62 to influence central sensitisation. For instance, women are more sensitive to painful sensory stimuli than men, but the biological sex influence decreases with increasing age, 62 and in nontraumatic neck pain remote mechanical hyperalgesia is negatively associated with age (R²=25•4%, p=0•031).…”

“…For instance, women are more sensitive to painful sensory stimuli than men, but the biological sex influence decreases with increasing age, 62 and in nontraumatic neck pain remote mechanical hyperalgesia is negatively associated with age (R²=25•4%, p=0•031). 61 Patientreported out comes, such as the Central Sensitiza tion Inventory (CSI), 63 have also been used to measure central sensitisation, and they are practical to use in nearly every clinical setting. By contrast with QST, which assesses responses of the sensory system to sensory input, patient reported outcomes primarily assess symp toms considered to be related to central sensitisation (eg, unrefreshing sleep, sleep problems, sensitivity to light, spreading pain, concentration difficulties, stress as an aggravating factor, sensitivity to odours, restless legs).…”

Does My Neck Make Me Clumsy? A Systematic Review of Clinical and Neurophysiological Studies in Humans

“…While the studies included in this review did not use quantitative sensory testing of pain to examine the presence of central sensitization except for the article of Steinmetz and Jull ( 24 ), we did find evidence for an association between the extent of deterioration in performance of upper limb sensorimotor tasks and self-reported measures of pain, physical functioning and levels of reported self- efficacy. There is evidence, that central sensitization is responsible for ongoing reports of pain and disability in people suffering chronic WAD ( 43 ) and altered central pain processing in those with non-traumatic neck pain ( 44 ). Future studies need to examine if disturbed body schema is part of central sensitization, and partly responsible for deteriorated quality of life and disability associated with chronic musculoskeletal pain.…”