An Approach to Assessment of Female Urinary Incontinence Risk using the Thickness of the Transverse Abdominal Muscle during Co-contraction of both the Transverse Abdominal Muscle and the Pelvic Floor Muscle

Abstract

Abstract. [Purpose] This study examined physical factors associated with urinary incontinence (UI) in women. We hypothesized that, women with UI would show decreased thickness of the transverse abdominal muscle (TA) during maximal co-contraction of both TA and the pelvic floor muscle (PFM) compared with the women with no history of UI.[Subjects] The subjects were thirty-two women who subjects were divided into two groups: the UI group and the No-UI group. [Methods] We evaluated the thickness of TA by ultrasound, and hand-grip strength and the muscular strength of adduction in flexion of hip joint. The thickness of TA was measured during performance of 4 tasks: (1) at rest, (2) maximal contraction of TA, (3) maximal contraction of PFM, and (4) maximal co-contraction of both TA and PFM.[Results] The No-UI group had thicknesses of TA that were greater than those seen in the UI group in the tasks 3 and 4. In logistic regression analysis with UI as the dependent variable, the thickness of TA during maximal cocontraction was identified as an independent factor, and the cut-off value of the thickness of TA was 2.55 mm as determined by the Receiver-Operating-Characteristic (ROC) curve. [Conclusion] We found that the thickness of TA during maximal co-contraction of both TA and PFM is reliable and useful for the evaluating the risk of UI in women.

An Approach to Assessment of Female Urinary Incontinence Risk Using the Thickness of the Transverse Abdominal Muscle

“…This finding is consistent with our previous study 10) . In the present study, the cut-off value of the thickness of TA during maximal cocontraction of both TA and PFM was 5.00 mm, as determined from the ROC curve, and the sensitivity was 81% and the specificity was 64%.…”

Pelvic floor and abdominal muscle cocontraction in women with and without pelvic floor dysfunction: a systematic review and meta-analysis

“…Four studies (28,32,33,39) considered different positions – standing, sitting and supine, and one did not report the position for the assessment of coactivity (26). Fifteen studies (8,9,23,25,26,28,30-35,37-39) measured the contraction by EMG, four studies (22,24,27,36) measured the contraction by US, and one study (29) measured the contraction by visual inspection and digital palpation scale (Table 2).…”

“…Six observational studies compared women with and without PFD. The main problems with the studies were follow-up (24,29,31,34,36,38), information regarding cointerventions (24,29,31,34,36,38), assessment of outcome (24,29,34,36,38) and exposure (31,36,38). Table 3 details the description for each study.…”

“…The results from two studies (24,36) with a total of 52 participants assessing cocontraction by US failed to show a difference in the cocontraction of the TrA in women with and without PFD (SMD −0.61 [95% CI −1.41 to 0.20], p =0.14; I 2 = 41%) (Figure 3). However, a plausible sensitivity analysis, excluding the study of Arab et al (24), yielded results that were inconsistent with the primary analysis, showing higher coactivity of the TrA during MVC of the PFMs in women without PFD (SMD −1.02 [95% CI −1.90 to −0.14], p =0.02; I 2 = not applicable) (Figure 4).…”

“…The fibers from the TrA are prolonged by the transverse perineal muscle because these muscles belong to the same muscle chain. This is an important conclusion for rehabilitation therapy, since numerous studies focus only on TrA strengthening to induce greater contractile strength of PFMs (22,27,35,36). Knowledge of the synergism among PFMs and AbMs may be useful for assessing PFMs and teaching women how to perform PFM exercises.…”