TUMOR-NECROSIS-FACTOR, INTERLEUKIN-1-BETA, AND TISSUE OXYGEN LEVELS IN MYOFASCIAL PAIN AND FIBROMYALGIA SYNDROMES

Objectives: First, to determine the serum levels of the cytokines tumo r necrosis factor [TNF-alpha] and interleukin-1 beta [IL-1 beta] and t issue oxygen levels in groups of patients with chronic, soft-tissue-pa in fibromyalgia [FMS], myofascial pain syndrome [MPS], and in healthy controls. Second, to determine if any differences exist between FMS an d MPS subjects in relation to the above-mentioned parameters. Methods: Ten patients who fulfilled the established criteria for FMS, 10 patie nts who fulfilled the established criteria for MPS, and 10 healthy con trols comprised the subject groups. A trigger or tender point in the u pper trapezius muscle was identified and a tissue oximeter [RunMan dev ice] was placed over that point to record tissue oxygen levels. The su bjects then abducted the ipsilateral shoulder to 90 degrees for 5 minu tes [min] with no additional weight, for 3 min with a l-kg weight, and for 2 min with a 2-kg weight, with 4-min rest intervals between each contraction exercise. Blood was drawn at baseline before exercise, and then again at intervals up to 60 min after the final contraction/rela xation trial. The tissue oximeter readings were recorded for the entir e exercise protocol and for five min thereafter, Results: The tissue o ximeter, which measures deoxygenated blood in situ, detected no signif icant differences in tissue oxygenation among the three groups. The FM S and MPS subjects did not have a significantly higher serum TNF-alpha level than the controls. Most of the subjects in all three groups had non-detectable serum lL-1 beta levels. Conclusion: The origin of MPS and FMS pain does not appear to be related to local tissue hypoxia or to cytokine-induced soft tissue sensitization.