N80
Conditions
Interventions
Group 1: Participants diagnosed with endometriosis. Their pelvic floor muscle tension will be measured using sEMG in the lab and are exposed to experimental stressors. They then receive a biofeedback
Sponsors
Philipps Universität Marburg
Eligibility
Sex/Gender
All
Age
18 Years to 49 Years
Inclusion criteria
Inclusion criteria: For participants with endometriosis: ? A histologically confirmed diagnosis of endometriosis that was made at least six months prior. ? Participants must have been suffering from chronic pelvic pain for at least six months, with a pain intensity of at least 4 on the Visual Analogue Scale (VAS) (0 = no pain, 10 = worst imaginable pain). ? Sufficient knowledge of German is required to complete the study-related questionnaires. ? Other pelvic floor disorders, such as irritable bowel syndrome, interstitial cystitis, pudendal neuralgia, or vulvodynia, are not excluded, but will be considered as control variables. For healthy controls: ? Sufficient knowledge of German to understand and complete the study and related questionnaires.
Exclusion criteria
Exclusion criteria: Exclusion criteria for participants with endometriosis: ? Inability to undergo a pelvic examination, such as in cases of vaginismus Previous participation in biofeedback therapy ? Current pregnancy, breastfeeding, or a vaginal birth in the last two years ? Use of hormonal treatments for less than three months or long-term use of pain medications ? Presence of severe internal (I50, 125, C00-C97, K70-K77, N18), neurological (G30, G35, G40, G20, G93.4), or psychiatric disorders , such as schizophrenia (F20, F22, F23.1), dementia (F00-F03), or alcohol/substance abuse (F10-F19), or affective disorder (F30. F31, F32.2, F33.2, F32.3, F33.3), or acute suicidality ? Nickel allergy ? Prior experience with biofeedback Exclusion criteria for healthy controls: ? Inability to undergo a pelvic examination, such as in cases of vaginismus ? Presence of endometriosis or other pelvic floor disorders, such as irritable bowel syndrome, interstitial cystitis, pudendal neuralgia, or vulvodynia ? Presence of severe internal (I50, 125, C00-C97, K70-K77, N18), neurological (G30, G35, G40, G20, G93.4), or psychiatric disorders , such as schizophrenia (F20, F22, F23.1), dementia (F00-F03), or alcohol/substance abuse (F10-F19), or affective disorder (F30. F31, F32.2, F33.2, F32.3, F33.3), or acute suicidality ? Use of hormonal treatments for less than three months or long-term use of pain medications ? Current pregnancy, breastfeeding, or a vaginal birth in the last two years ? Nickel allergy ? Prior experience with biofeedback
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| 1) Physiological endpoint: Pelvic floor muscle activity, measured as the difference in muscle tension (mean in microvolts, µV) between the study groups. Measurement will be performed in a single session using surface electromyography (sEMG) with a vaginal probe. Two consecutive protocols will be applied: a) Glazer protocol (Glazer & Hacad, 2012): Assessment of muscle activity in different functional states: •Mean muscle tone at rest •Peak activity during maximal voluntary contraction •Stability of muscle activity during a 10-second hold phase •Return of muscle activity to baseline after contraction •Contraction-to-rest ratio b) Stimulus protocol: Immediately following the Glazer protocol, a stress-induced protocol will be conducted, consisting of four stressors (each: 3 minutes stressor, 2 minutes recovery phase, 1 minute rest phase). The mean pelvic floor muscle tone (µV) will be measured during the rest phases and at minute 2 of each stress phase. 2) Psychological endpoint: Acceptance of the biofeedback session Assessed once after the biofeedback session in the endometriosis group using a self-developed evaluation form (17 items total), consisting of 11 closed questions assessing usability, perceived ability to modulate muscle activity, and willingness for further use, as well as 4 open-ended questions for qualitative feedback. Reference: Glazer, H. I., Rodke, G., Swencionis, C., Hertz, R., & Young, A. W. (1995). Treatment of vulvar vestibulitis syndrome with electromyographic biofeedback of pelvic floor musculature. The Journal of Reproductive Medicine, 40(4), 283–290. | — |
Secondary
| Measure | Time frame |
|---|---|
| Single assessment conducted exclusively in the endometriosis group using validated questionnaires. Before the physiological assessment: • Pain intensity: VAS (Cleeland & Ryan, 1994) • Self-efficacy: FESS (Mangels et al., 2009) • Pain catastrophizing: PCS (Sullivan et al., 1995) • Central sensitization: CSI (Mayer et al., 2012) • Mental health: WSQ (Donker et al., 2009), PHQ-9 (Kroenke et al., 2001) • Endometriosis-related quality of life: EHP-30 (Jones et al., 2001) • Treatment expectations: GEEE (Rief et al., 2021), TEX-Q (Shedden-Mora et al., 2023) After the biofeedback session: • Negative treatment effects: NEQ (Rozental et al., 2019) References: Cleeland, C. S., & Ryan, K. M. (1994). Pain assessment: Global use of the Brief Pain Inventory. Annals of the Academy of Medicine, Singapore, 23(2), 129–138. Donker, T., Straten, A. van, Marks, I. M., & Cuijpers, P. (2009). A Brief Web-Based Screening Questionnaire for Common Mental Disorders: Development and Validation. Journal of Medical Internet Research, 11(3), e1134. https://doi.org/10.2196/jmir.1134 Jones, G., Kennedy, S., Barnard, A., Wong, J., & Jenkinson, C. (2001). Development of an endometriosis quality-of-life instrument: The Endometriosis Health Profile-30. Obstetrics and Gynecology, 98(2), 258–264. https://doi.org/10.1016/s0029-7844(01)01433-8 Kroenke, K., Spitzer, R. L., & Williams, J. B. (2001). The PHQ-9: Validity of a brief depression severity measure. Journal of General Internal Medicine, 16(9), 606–613. https://doi.org/10.1046/j.1525-1497.2001.016009606.x Mangels, M., Schwarz, S., Sohr, G., Holme, M., & Rief, W. (2009). Der Fragebogen zur Erfassung der schmerzspezifischen Selbstwirksamkeit (FESS). Diagnostica. https://econtent.hogrefe.com/doi/10.1026/0012-1924.55.2.84 Mayer, T. G., Neblett, R., Cohen, H., Howard, K. J., Choi, Y. H., Williams, M. J., Perez, Y., & Gatchel, R. J. (2012). The development and psychometric validation of the central sensitization inventory. Pain Practice | — |
Countries
Germany
Contacts
Public ContactCornelia Weise
Friedrich-Alexander Universität Erlangen-Nürnberg
Outcome results
None listed