Vulvodynia: a psychophysiological profile based on electromyographic assessment

The objective of this study was to explore the relationship between psychological and physiological processes and how these interact in the case of vulvodynia. The study design consisted of a retrospective review of predominantly premenopausal women presenting with vulvodynia via analyses of questionnaires, psychometric tests, sexual history, surface electromyographic (sEMG) assessments, and clinical notes. Five hundred and twenty-nine patients with vulvodynia (mean age 27.7 years) were studied. The average age of symptom onset was 22.8 years and the average duration of symptoms was 5.0 years. Patients scored higher than the comparison group on global dimensions of the Symptom Checklist-90 Revised (SCL-90R), with anxiety and depression scores showing a significant but modest correlation with severity of pain. sEMG data confirmed an association with pelvic muscle dysfunction but there was no correlation with severity of vulvar pain. A negative correlation between sEMG readings and duration of pain was noted and may be due to progressive time-related quieting of electrical activity in muscle tissues, which is commonly associated with the development of a functional muscle contracture. In conclusion, it is important to view chronic pain syndromes like vulvodynia from a psychophysiological perspective which recognizes the potential contribution of psychological and physiological variables in the aetiology of chronic vulvar pain.