[Tissue pO2 measurement in taut back musculature (m. erector spinae)]

Measurements with polarographic needle probes in fibromyalgic muscles (mm. erectores spinae) revealed an elevated mean tissue-pO2. The total mean tissue-pO2 in the patient group was significantly higher than that in the control group. Greater pathological tension in fibromyalgic muscles increases the mean tissue-pO2. The distribution of local tissue-pO2 values was normal; there was no evidence of small hypoxic areas in the muscle. The elevated tissue-pO2 in fibromyalgic muscles could either be explained by an increase in local blood flow or by disturbance of oxygen-utilization of the muscle cells. The mean tissue-pO2 in patients treated with NSAD was lower than in patients without this treatment. Myogelosises (i.e., circumscript tautness in muscles, that, contrary to fibromyalgic muscles, do not relax under general anesthesia) showed low tissue-pO2 values and even hypoxia in the core. In myogelosises, pain could be hypoxic in nature. However, in fibromyalgic muscles no evidence for hypoxia or hypoxia-related pain could be found.