Development of a Pelvic Floor Muscle Strength Evaluation Device
Jittima Manonai MD*, Sakuntala Kamthaworn MSc**, Kuson Petsarb MSc**, Rujira Wattanayingcharoenchai MD*
Affiliation : * Department of Obstetrics & Gynaecology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand ** Biomedical Instrumentation Research and Development Center, Institute of Molecular Biosciences, Mahidol University, Bangkok, Thailand
Objective : To validate the device and investigate the effect of this device on symptoms, quality of life, and pelvic floor muscle
strength.
Material and Method: The device was designed to measure vaginal pressure changes using air-pressure balloon and
abdominal wall muscle activities using surface electromyography. To test the accuracy of the device, for vaginal pressure
measurement, a Mercury sphygmomanometer was used as a gold standard, and for abdominal wall muscle activity, a
standard biofeedback machine was used as a reference device. A randomized, controlled trial was conducted in sixty-one
women with stress urinary incontinence. They were randomly divided into two groups undergoing PFMT with a single
15-minute biofeedback session (BF + PFMT group) or without biofeedback (PFMT group). The pelvic floor muscle strength,
abdominal wall muscle activity and incontinence-specific quality of life questionnaire (I-QOL), measurements were evaluated
at baseline and at 8- and 16-week after treatment.
Results : The accuracy of vaginal probe pressure perineometry was 98% compared to a standard sphygmomanometer. The
device could detect abdominal wall muscles activities at 10 milliseconds (100 Hz), 20 milliseconds (50 Hz), and 50 milliseconds
(20 Hz). After 8 and 16 weeks of treatment, there were statistically significant intra-group differences in the maximum vaginal
squeeze pressure in both groups. However, the inter-group differences were not demonstrated. The proportion of women
who performed pelvic floor muscle exercise correctly was significantly higher in the BF + PFMT group (72.41%) compared
to the PFMT group (21.88%) at week 16 (p<0.05).
Conclusion : The simple pelvic floor muscle strength evaluation device might be helpful in pelvic floor muscle training in
a low resource setting.
Keywords : Device, Pelvic floor muscle, Quality of life, Stress urinary incontinence, Biofeedback
