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

Daiana Priscila Rodrigues-De-Souza,Juan Luis Garrido-Castro,Inés Cruz-Medel,Sandra Alcaraz-Clariana,Lourdes García-Luque,Paula R Camargo,Francisco Alburquerque-Sendín,Cristina Carmona-Pérez

doi:10.3390/diagnostics11122315

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.

Highlights

The pelvic floor (PF) is a complex set of connective tissues and striated muscles that simultaneously counteract inertial forces and intra-abdominal pressures while maintaining the position of the pelvic organs [1]
The most common type of incontinence in this population is stress urinary incontinence (SUI), defined as the involuntary loss of urine that occurs through physical exertion, such as sneezing or coughing [8], and which exceeds 60% of the total UI cases reported in this female population, mixed UI and urgency UI are found [4]
The present study showed good to excellent intra-rater and inter-rater reliability for the determination of muscle mechanical properties (MMPs), and for measurement of tone and biomechanical properties, such as stiffness and decrement, in pelvic floor muscles (PFMs)

Summary

Introduction

The pelvic floor (PF) is a complex set of connective tissues and striated muscles that simultaneously counteract inertial forces and intra-abdominal pressures while maintaining the position of the pelvic organs [1]. The pelvic floor muscles (PFMs) support the pelvic organs through coordinated contraction and relaxation. An increase in intra-abdominal pressure reflexively contracts the PFM, closing the vaginal, urethral and anal hiatus [2]. One of the consequences of the deterioration of these mechanisms is urinary incontinence (UI) [3], which negatively impacts on quality of life and limits activities of daily living [4]. The effect of risk factors for SUI on the PFMs may not be evident until later stages in life [9,10,11], which increases the relevance of the evaluations of PFM, even in subclinical phases

Objectives

Discussion

Conclusion