Vulvodynia is a chronic vulvar pain disorder and fibromyalgia is a chronic widespread musculoskeletal pain disorder, both of unknown etiology. Association of these conditions is well documented. Intravaginal algometer measurement of tenderness to pressure applied to the pelvic floor muscles helps define vulvodynia associated with musculoskeletal factors. Women with both vulvodynia and fibromyalgia might have increased pelvic muscle pain compared to women with vulvodynia alone, defining the possible link of these 2 conditions.
We sought to: (1) correlate pain intensity during the nongenital tender point tenderness examination to pain intensity with the vaginal algometer in women with provoked vestibulodynia, and (2) determine whether subjects with provoked vestibulodynia and fibromyalgia had higher pain intensity scores with the vaginal algometer than those without fibromyalgia.
In all, 92 subjects referred for vulvar pain were confirmed to have provoked vestibulodynia using the cotton swab test. A diagnosis of fibromyalgia was made if pain was present (numeric rating scale >1) in at least 11 sites of the 18-point nongenital tender point tenderness exam. Vaginal pain sensitivity was measured using an intravaginal pressure algometer, where 0.1, 0.3, and 0.5 kg/cm
A significant correlation was found between numeric rating scale pain scores on the nongenital tender point tenderness exam and algometer testing on the iliococcygeus region (r = 0.44, P < .0001) and the posterior vaginal wall (r = 0.45, P < .0001). Subjects with fibromyalgia by tender point tenderness had significantly higher iliococcygeal pain (6.14 ± 2.07 vs 3.74 ± 2.22, P = .0001) and posterior vaginal wall pain (5.67 ± 2.10 vs 3.07 ± 2.16, P < .0001) than women without fibromyalgia by tender point tenderness.
Women with provoked vestibulodynia who experience more severe pain with nongenital tender point palpation also experience more deep vaginal pain on pelvic exam. Those who fulfill the diagnosis of fibromyalgia show significantly more intense deep vaginal pain to palpation of iliococcygeus muscles and posterior vaginal wall. Further research using a more precise definition of fibromyalgia is necessary to confirm this relationship, but findings suggest that women with provoked vestibulodynia coexisting with fibromyalgia have greater risk of superimposed vaginal muscle pain and may be candidates for early adjunctive pelvic floor physical therapy. These findings need to be explored in women with generalized, nonprovoked vulvodynia.