The state of pelvic floor muscle dynamometry: A scoping review.

AIMS: To discuss the advantages and limitation of the different pelvic floor muscle (PFM) dynamometers available, both in research and industry, and to present the extent of variation between them in terms of structure, functioning, psychometric properties, and assessment procedures. METHODS: We identified relevant studies from four databases (MEDLINE, Compendex, Web of Science, and Derwent Innovations Index) up to December 2020 using terms related to dynamometry and PFM. In addition, we conducted a hand search of the bibliographies of all relevant reports. Peer-reviewed papers, conference proceedings, patents and user's manuals for commercial dynamometers were included and assessed by two independent reviewers. RESULTS: One hundred and one records were included and 23 PFM dynamometers from 15 research groups were identified. From these, 20 were considered as clinical dynamometers (meant for research settings) and three as personal dynamometers (developed by the industry). Overall, significant heterogeneity was found in their structure and functioning, which limits development of normative data for PFM force in women. Further research is needed to assess the psychometric properties of PFM dynamometers and to standardize assessment procedures. CONCLUSION: This review points up to the heterogeneity of existing dynamometers and methods of assessing PFM function. It highlights the need to better document their design and assessment protocol methods. Additionally, this review recommends standards for new dynamometers to allow the establishment of normalized data.

Portable Dynamometer-Based Measurement of Pelvic Floor Muscle Force.

OBJECTIVE: In attempts to improve the quality of life of women, continuous projects are sought between rehabilitation intervention and engineering. Using the knowledge of the pelvic floor muscle (PFM) physiology, assessment and training methods are developed to reduce lower urinary tract symptoms such as urinary incontinence. Therefore, this paper covers the design and implementation of a portable vaginal dynamometer. METHODS: A PFM probe is designed, 3D printed, assembled, and tested in ten women to assess its acceptability and usability. The feedback from the usability study is used to optimize the PFM probe design. A vaginal dynamometer is developed based on the designed PFM probe, then tested for linearity, repeatability, hysteresis, noise and heat effect, and power consumption. The variability between the different produced PFM probe prototypes is evaluated. RESULTS: Force measurements are made using a load cell. Wireless communication is performed through a Bluetooth low energy transceiver v5.0, with a corresponding interface on both computer and smartphone. The device operates at a 3.3V supply and achieves a power consumption of 49.5 mW in operating mode. Two PFM probe sizes are designed to accommodate different vaginal hiatus sizes, based on usability study feedback. The proposed system allows the physiotherapist to wirelessly monitor variation in pelvic floor muscle force during assessment and/or training. DISCUSSION/CONCLUSION: The testing results showed that the newly designed system has the potential to measure the PFM function in functional conditions such as the standing position.

A Dynamometer-based Wireless Pelvic Floor Muscle Force Monitoring.

This paper covers the design and implementation of a proof of concept for a wireless system measuring pelvic floor muscle forces based on a dynamometer. The proposed device is the main component of a novel assessment tool intended for pelvic floor muscle rehabilitation in women suffering from urinary incontinence. The proposed system allows the physiotherapist to wirelessly monitor variation in pelvic floor muscle forces during assessment or training. Wireless communication is provided by a Bluetooth low energy transceiver and a corresponding interface designed for this purpose. Force measurements are sensed with strain gauge precision sensors operated in a Wheatstone bridge configuration. The designed module consumes 14 mW of power in operating mode. System design and experimental results are reported and discussed.