Turn-amplitude analysis as a diagnostic test for myofascial syndrome in patients with chronic pelvic pain

BACKGROUND: Myofascial pain syndrome of the pelvic floor (MPSPF) is a common disease in the context of chronic pelvic pain (CPP); however, there is currently no gold-standard test to diagnose it. OBJECTIVE: To validate the turns-amplitude analysis (TAA) as a diagnostic test for MPSPF in patients with CPP. METHODS: A case-control study was performed, and patients were consecutively sampled within a specified period of time. A total of 128 patients were included: 64 patients with CPP (32 men and 32 women) and 64 control patients (32 men and 32 women). The same operator conducted all tests. Electromyography of the TAA is based on the collection of motor unit potentials that measure the number of changes in the signal and the mean amplitude of the changes. The electromyogram transfers the data to a graphical point cloud, which enables the patient’s results to be compared with the results of the healthy subjects. RESULTS: In patients and control subjects, the sensitivity and specificity of the proposed diagnostic test showed a marked clinical significance: the sensitivity was 83%, and the specificity was 100%. A positive predictive value of 1 (95% CI 1 to 1) and a negative predictive value of 0.85 (95% CI 0.77 to 0.93) were observed. CONCLUSION: TAA is a reliable diagnostic test to detect MPSPF. Further studies are needed to reproduce these results.