File
Aljuraifani R1,2, Stafford R1, Hodges P1
1University of Queensland, Brisbane, Australia, 2Princess Nourah Bint Abdulrahman University, Riyadh, Saudi Arabia
Background: Pelvic floor muscles (PFM) are anatomically arranged in deep and superficial layers. Each layer includes several muscles, and preliminary evidence shows that the layers contract deferentially during voluntary and involuntary tasks.
Purpose: This study aimed to simultaneously investigate contraction characteristics of deep and superficial PFM layers across a range of tasks using transperineal ultrasound imaging (US).
Methods: Seventeen females without pelvic floor dysfunction participated. Displacement of pelvic floor landmarks produced by contraction of deep and superficial PFM was measured from US images made during four tasks: two submaximal voluntary contractions (using different verbal instructions), maximal voluntary contraction (MVC) and a ramped Valsalva manoeuvre. Temporal and spatial features of landmark displacement were analysed.
Results: The time of onset and peak displacement of the superficial PFM was earlier than that for the deep PFM during the submaximal and maximal voluntary contractions (P≤0.01). Amplitude of displacement was greater for MVC than submaximal tasks for deep (P 0.001) but not superficial (P>0.42) PFM. Shortening of deep PFM was sustained for longer (P= 0.0037) and with greater steadiness during the MVC than superficial PFM. During the Valsalva, superficial PFM lengthened for most participants, whereas deep PFMs mostly shortened. In this task, shortening (when present) was less than that recorded for the voluntary PFM contractions (All: P 0.05).
Conclusion(s): Properties of contraction differed between deep and superficial PFM across all tasks in females without pelvic floor dysfunction. In general, contraction of superficial PFM was rapid but poorly sustained, whereas deep PFM contraction was slower and could be maintained smoothly for longer periods. These data provide a foundation to investigate differences in pelvic floor conditions.
Implications: The results of the study provide evidence that spatial and temporal activation characteristics of PFM differ between the deep and superficial layers. The PFM complex cannot be addressed as a single unit during function assessment and these differences may have relevance for specific urogynaecological conditions.
Keywords: Pelvic floor muscles, ultrasound imaging, bulbocavernosus
Funding acknowledgements: provided by the National Health and Medical Research Council (NHMRC) of Australia (Fellowship to PH (APP1002190); Program Grant (ID631717))
Purpose: This study aimed to simultaneously investigate contraction characteristics of deep and superficial PFM layers across a range of tasks using transperineal ultrasound imaging (US).
Methods: Seventeen females without pelvic floor dysfunction participated. Displacement of pelvic floor landmarks produced by contraction of deep and superficial PFM was measured from US images made during four tasks: two submaximal voluntary contractions (using different verbal instructions), maximal voluntary contraction (MVC) and a ramped Valsalva manoeuvre. Temporal and spatial features of landmark displacement were analysed.
Results: The time of onset and peak displacement of the superficial PFM was earlier than that for the deep PFM during the submaximal and maximal voluntary contractions (P≤0.01). Amplitude of displacement was greater for MVC than submaximal tasks for deep (P 0.001) but not superficial (P>0.42) PFM. Shortening of deep PFM was sustained for longer (P= 0.0037) and with greater steadiness during the MVC than superficial PFM. During the Valsalva, superficial PFM lengthened for most participants, whereas deep PFMs mostly shortened. In this task, shortening (when present) was less than that recorded for the voluntary PFM contractions (All: P 0.05).
Conclusion(s): Properties of contraction differed between deep and superficial PFM across all tasks in females without pelvic floor dysfunction. In general, contraction of superficial PFM was rapid but poorly sustained, whereas deep PFM contraction was slower and could be maintained smoothly for longer periods. These data provide a foundation to investigate differences in pelvic floor conditions.
Implications: The results of the study provide evidence that spatial and temporal activation characteristics of PFM differ between the deep and superficial layers. The PFM complex cannot be addressed as a single unit during function assessment and these differences may have relevance for specific urogynaecological conditions.
Keywords: Pelvic floor muscles, ultrasound imaging, bulbocavernosus
Funding acknowledgements: provided by the National Health and Medical Research Council (NHMRC) of Australia (Fellowship to PH (APP1002190); Program Grant (ID631717))
Topic: Women's & men's pelvic health
Ethics approval required: Yes
Institution: University of Queensland (UQ)
Ethics committee: The Medical Research Ethics Committee of UQ
Ethics number: 2010000545
All authors, affiliations and abstracts have been published as submitted.
