Morgan Daniel M, Kaur Gurpreet, Hsu Yvonne, Fenner Dee E, Guire Kenneth, Miller Janis, Ashton-Miller James A, Delancey John O L
Department of Obstetrics and Gynecology, Pelvic Floor Research Group, University of Michigan Medical School, Ann Arbor 48109, USA.
Am J Obstet Gynecol. 2005 May;192(5):1722-8. doi: 10.1016/j.ajog.2004.11.050.
This study was undertaken to quantify resting vaginal closure force (VCF(REST)), maximum vaginal closure force (VCF(MAX)), and augmentation of vaginal closure force augmentation (VCF(AUG)) when supine and standing and to determine whether the change in intra-abdominal pressure associated with change in posture accounts for differences in VCF.
Thirty-nine asymptomatic, continent women were recruited to determine, when supine and standing, the vaginal closure force (eg, the force closing the vagina in the mid-sagittal plane) and bladder pressures at rest and at maximal voluntary contraction. VCF was measured with an instrumented vaginal speculum and bladder pressure was determined with a microtip catheter. VCF(REST) was the resting pelvic floor tone, and VCF(MAX) was the peak pelvic floor force during a maximal voluntary contraction. VCF(AUG) was the difference between VCF(MAX) and VCF(REST). T tests and Pearson correlation coefficients were used for analysis.
VCF(REST) when supine was 3.6 +/- 0.8 N and when standing was 6.9 +/- 1.5 N--a 92% difference (P < .001). The VCF(MAX) when supine was 7.5 +/- 2.9 N and when standing was 10.1 +/- 2.4 N--a 35% difference (P < .001). Bladder pressure when supine (10.5 +/- 4.7 cm H2O) was significantly less (P < .001) than when standing (31.0 +/- 6.4 cm H2O). The differences in bladder pressure when either supine or standing did not correlate with the corresponding differences in VCF at rest or at maximal voluntary contraction. The supine VCF(AUG) of 3.9 +/- 2.7 N, was significantly greater than the standing VCF(AUG) of 3.3+/-1.9 N.
With change in posture, vaginal closure force increases because of higher intra-abdominal pressure and greater resistance in the pelvic floor muscles.
本研究旨在量化仰卧位和站立位时的静息阴道闭合力（VCF(REST)）、最大阴道闭合力（VCF(MAX)）以及阴道闭合力增强（VCF(AUG)），并确定与姿势改变相关的腹内压变化是否可解释VCF的差异。
招募39名无症状、控尿正常的女性，以确定其仰卧位和站立位时的阴道闭合力（如矢状面中部闭合阴道的力）以及静息和最大自主收缩时的膀胱压力。使用装有传感器的阴道窥器测量VCF，并用微尖导管测定膀胱压力。VCF(REST)为静息盆底张力，VCF(MAX)为最大自主收缩时的盆底峰值力。VCF(AUG)为VCF(MAX)与VCF(REST)之差。采用t检验和Pearson相关系数进行分析。
仰卧位时VCF(REST)为3.6±0.8N，站立位时为6.9±1.5N，相差92%（P<.001）。仰卧位时VCF(MAX)为7.5±2.9N，站立位时为10.1±2.4N，相差35%（P<.001）。仰卧位时膀胱压力（10.5±4.7cm H2O）显著低于站立位时（31.0±6.4cm H2O）（P<.001）。仰卧位或站立位时膀胱压力的差异与静息或最大自主收缩时VCF的相应差异无关。仰卧位时VCF(AUG)为3.9±2.7N，显著大于站立位时的VCF(AUG) 3.3±1.9N。
随着姿势改变，由于腹内压升高和盆底肌肉阻力增大，阴道闭合力增加。
