Absolute and Relative Reliability of the Assessment of the Muscle Mechanical Properties of Pelvic Floor Muscles in Women with and without Urinary Incontinence

Abstract

An analysis of the muscle mechanical properties (MMPs) of the pelvic floor muscles (PFMs) is relevant for understanding the physiopathology of urinary incontinence (UI). However, there is no objective and reliable methodology currently available for quantifying the MMPs of PFMs. Thus, the objective was to determine the intra-rater and inter-rater reliability of the MMPs of PFM assessment with a hand-held tonometer device, called the MyotonPRO, in young women with and without UI. Sociodemographic and pelvic floor questionnaires, plus MMPs of PFMs were assessed in 38 nulliparous women with UI and 40 matched healthy women by two trained physiotherapists on two different occasions, 48–72 h apart. Good to excellent absolute reliability was found for tone, stiffness, and decrement of both intra- and inter-rater analyses in both study groups (Intraclass Correlation Coefficient ranged from 0.75 to 0.92), with a trend of lower values for relaxation and creep. The standard error of measurement (SEM) did not achieve 10% of the mean values for any MMPs. The minimum detectable change (MDC) values were also provided for clinical applications. In conclusion, the relative reliability of tone, stiffness, and the assessment of the decrement of PFMs with MyotonPRO is good to excellent for UI and healthy women. The SEM and MDC values were acceptable for their application in clinical settings.

Influence of vaginal birth on lumbopelvic muscle mechanical properties on urinary incontinence

“…26 A Visual Analog Scale was also applied to identify any pain or discomfort due to the measurements. 20 Afterwards, MMP measurements of the PF and LP muscles were performed bilaterally with a handheld tonometer (MyotonPRO Myoton AS, Estonia). 27 During the assessment of the MMP of the PF, the volunteers were positioned supine on a table with the knees flexed and the feet resting on the table (modified lithotomy position).…”

“…To estimate the sample size, a minimum detectable difference of 0.86 Hz and a pooled standard deviation of 1.23 Hz were used for the PF frequency, 20 resulting in a medium effect size (f = 0.35). Assuming a power of 0.9 and a significance level of 0.05, for a one-covariate ANCOVA model, the number of subjects needed per subgroup is at least 22 (G*Power 3.1.9.2).…”

“…11,12 Although the assessment of MMP is considered relevant in the clinical settings of different regions, including spinal 13 and PF disorders, 14,15 the previously used methods for muscle assessment have focused exclusively on measuring different types of muscle force 16 and electromyographic activity, 17 or are based on subjective approaches. 18,19 However, valid, reliable, noninvasive, inexpensive, and portable tools, such as hand-held tonometers, are now available to determine MMP, both at PF 20,21 and LP levels. 22,23 Tonometry is based on the application of mechanical impulses to soft biological tissues, with predefined time and pulse force, to record the dynamic tissue response in the form of physical displacement and oscillation acceleration signal.…”

Multifunctional Evaluation Technology for Diagnosing Malfunctions of Regional Pelvic Floor Muscles Based on Stretchable Electrode Array Probe

“…For example, the vaginal pressure airbag is a common device for evaluating PFM force [ 12 , 13 ]. Handheld devices are used for measuring the mechanical properties of PFM [ 14 ]. The surface electromyogram (sEMG) is the main technology for evaluating the PFM activity status in clinic [ 8 , 15 , 16 , 17 ].…”

Influence of Spinal Movements Associated with Physical Evaluation on Muscle Mechanical Properties of the Lumbar Paraspinal in Subjects with Acute Low Back Pain

“…However, their high cost makes them inaccessible to a clinical setting, challenging the determination of the MMPs. Since a decade ago, the device MyotonPRO© emerged as a non-invasive and reliable alternative to assess and monitor MMPs with clinical applications Several studies have shown sufficient accuracy and precision to determine MMPs in spinal muscles [ 23 , 24 , 25 , 26 ] and other tissues and regions [ 23 , 27 , 28 , 29 ], although efforts to better determine the concurrent validity need further research [ 30 ]. Previous research has associated MMPs alterations, specifically an increase in stiffness and tone or a decrease in elasticity, and axial spondyloarthritis [ 24 ].…”