PMID- 33351923 OWN - NLM STAT- MEDLINE DCOM- 20210625 LR - 20210625 IS - 1538-6724 (Electronic) IS - 0031-9023 (Linking) VI - 101 IP - 3 DP - 2021 Mar 3 TI - Enhanced Pronociceptive and Disrupted Antinociceptive Mechanisms in Nonspecific Chronic Neck Pain. LID - pzaa223 [pii] LID - 10.1093/ptj/pzaa223 [doi] AB - OBJECTIVE: Evidence suggests altered pronociceptive and antinociceptive mechanisms in many chronic pain conditions. Knowledge about these mechanisms in nonspecific chronic neck pain (NSNP) would improve understanding of the causes and the design of more effective treatments. Pressure pain threshold (PPT) is often used to assess presence of altered nociceptive processing in NSNP; however, its usefulness to detect this is yet to be established. The purpose of this study was to determine the functional status of temporal summation of second pain (TSSP) and conditioned pain modulation (CPM) in NSNP and to characterize the association of both measures with PPT and clinical features of NSNP. METHODS: Thirty-two participants with NSNP (mean [SD] age = 44 [11] years; 27 female) and 32 age- and sex-matched healthy controls were recruited. TSSP was assessed using an electrical stimulus at the dorsum of the hand, and CPM was evaluated with the Cold Pressor Test. PPT was assessed bilaterally at the neck and tibialis anterior muscles. RESULTS: Participants with NSNP showed greater TSPP (mean difference = 0.23; 95% CI = 0.46-0.01; Cohen d = 0.51) and lower CPM (mean difference = 19.44; 95% CI = 10.42-28.46; Cohen d = 1.09). Pooled data from all participants showed lower PPTs at the neck than the tibialis anterior. However, PPT measures did not differ between groups at either location. PPT measures were not correlated with CPM and TSP. CONCLUSION: NSNP is associated with enhanced pronociceptive and impaired antinociceptive mechanisms, which may explain long-lasting pain and failure of some treatments to resolve symptoms. However, due to the observational nature of this study, a clear cause-effect relationship cannot be established. Normal PPT values in the clinic should not be interpreted as absence of altered nociceptive processing. IMPACT: This study fills in some gaps in knowledge. Changes in central nociceptive processing may explain persistent and recurrent symptoms in NSNP and failure of treatments to obtain long-lasting relief. Further research is required to ascertain if TSSP and CPM assessment in the clinic may help predict physical therapy treatment outcome. Whether symptomatic relief with physical therapy is mediated by an improvement in TSSP and CPM should also be explored. PPTs were unaltered in participants with NSNP despite evidence of impairment in the central pain modulatory systems. Normal PPTs should not be interpreted as evidence of unaltered central pain-related processing. CI - (c) The Author(s) 2020. Published by Oxford University Press on behalf of the American Physical Therapy Association. All rights reserved. For permissions, please email: journals.permissions@oup.com. FAU - Zabala Mata, Josu AU - Zabala Mata J AD - Physiotherapy, Department of Physiology, Faculty of Medicine and Nursing, University of the Basque Country UPV/EHU, Leioa, Spain. AD - Department of Neurosciences, Faculty of Medicine and Nursing, University of the Basque Country UPV/EHU, Leioa, Spain. FAU - Lascurain-Aguirrebena, Ion AU - Lascurain-Aguirrebena I AD - Physiotherapy, Department of Physiology, Faculty of Medicine and Nursing, University of the Basque Country UPV/EHU, Leioa, Spain. FAU - Dominguez Lopez, Estibaliz AU - Dominguez Lopez E AD - Department of Neurosciences, Faculty of Medicine and Nursing, University of the Basque Country UPV/EHU, Leioa, Spain. FAU - Azkue, Jon Jatsu AU - Azkue JJ AD - Department of Neurosciences, Faculty of Medicine and Nursing, University of the Basque Country UPV/EHU, Leioa, Spain. LA - eng PT - Comparative Study PT - Journal Article PL - United States TA - Phys Ther JT - Physical therapy JID - 0022623 SB - IM MH - Adult MH - Case-Control Studies MH - Central Nervous System Sensitization/*physiology MH - Chronic Pain/*physiopathology MH - Disability Evaluation MH - Female MH - Humans MH - Male MH - Middle Aged MH - Neck Pain/*physiopathology MH - Pain Measurement MH - Pain Threshold/*physiology OTO - NOTNLM OT - Conditioned Pain Modulation OT - Neck Pain OT - Pressure Pain Threshold OT - Temporal Summation of Second Pain EDAT- 2020/12/23 06:00 MHDA- 2021/06/29 06:00 CRDT- 2020/12/22 17:14 PHST- 2020/05/12 00:00 [received] PHST- 2020/11/30 00:00 [accepted] PHST- 2020/12/23 06:00 [pubmed] PHST- 2021/06/29 06:00 [medline] PHST- 2020/12/22 17:14 [entrez] AID - 6044312 [pii] AID - 10.1093/ptj/pzaa223 [doi] PST - ppublish SO - Phys Ther. 2021 Mar 3;101(3):pzaa223. doi: 10.1093/ptj/pzaa223.