Open this publication in new window or tab >>Show others...
2005 (English)In: Pain, ISSN 0304-3959, E-ISSN 1872-6623, Vol. 119, no 1-3, p. 201-209Article in journal (Refereed) Published
Abstract [en]
The mechanisms behind the development of work-related trapezius pain are suggested to involve both peripheral and central components, but the specific contribution of alterations in muscle nociceptive and other substances is not clear. Female patients with chronic trapezius myalgia (N=19, TM) and female controls (N=20, CON) were studied at rest, during 20 min repetitive low-force exercise and recovery, and had their interstitial concentrations of potassium (K+), lactate dehydrogenase (LDH), interleukin-6 (IL-6) and collagen turnover determined in the trapezius muscle by the microdialysis technique. K+ levels were at all time points higher in TM than in CON (P<0.0001). Baseline levels of LDH and IL-6 were similar in both groups. In response to exercise pain intensity, rated perceived exertion, and the concentrations of K+, LDH and IL-6 increased significantly in both groups. [K+] immediately decreased to baseline levels in CON but remained elevated during the first 20 min of recovery in TM (P<0.01) whereafter it returned to baseline level. In all subjects taken together mean [K+] correlated negatively with pressure pain threshold of trapezius (P<0.001), positively with mean pain intensity VAS (P<0.001) and mean perceived exertion (P<0.001). Rises in muscle LDH and IL-6 as well as the anabolic ratio for collagen type I was not significantly different between groups. In conclusion, patients with chronic pain in the trapezius muscle had increased levels of interstitial potassium. This finding could be causally related to myalgia or secondary to pain due to deconditioned muscle or altered muscle activity pattern. © 2005 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:liu:diva-31094 (URN)10.1016/j.pain.2005.09.026 (DOI)16824 (Local ID)16824 (Archive number)16824 (OAI)
2009-10-092009-10-092017-12-13