Faculty of Mechanical and Electrical Engineering, Kunming University of Science and Technology, No.727, Jingming South Road, Chenggong District, Kunming, 650500, China.
The First Department of Urology, The First Affiliated Hospital of Kunming Medical University, 295 Xichang Road, Kunming, 650032, China.
Biomech Model Mechanobiol. 2023 Aug;22(4):1425-1446. doi: 10.1007/s10237-023-01729-y. Epub 2023 Jun 9.
We developed the pelvic floor model in physiological and pathological states to understand the changes of biomechanical axis and support that may occur from the normal physiological state to the prolapse pathological state of the pelvic floor. Based on the physiological state model of the pelvic floor, we model the uterus to the pathological state position by balancing intra-abdominal pressure (IAP) and uterine pathological position load. Under combined impairments, we compared the patterns of changes in pelvic floor biomechanics that may be induced by different uterine morphological characteristic positions under different IAP. The orientation of the uterine orifice gradually changes from the sacrococcygeal direction to the vertical downward of vaginal orifice, and a large downward prolapse displacement occurs, and the posterior vaginal wall shows "kneeling" profile with posterior wall bulging prolapse. When the abdominal pressure value was 148.1 cmHO, the descent displacement of the cervix in the normal and pathological pelvic floor system was 11.94, 20, 21.83 and 19.06 mm in the healthy state, and 13.63, 21.67, 22.94 and 19.38 mm in the combined impairment, respectively. The above suggests a maximum cervical descent displacement of the uterus in the anomalous 90° position, with possible cervical-uterine prolapse as well as prolapse of the posterior vaginal wall. The combined forces of the pelvic floor point in the direction of vertical downward prolapse of the vaginal orifice, and the biomechanical support of the bladder and sacrococcygeal bone gradually diminishes, which may exacerbate the soft tissue impairments and biomechanical imbalances of the pelvic floor to occur of POP disease.
我们构建了生理和病理状态下的盆底模型，以了解从正常生理状态到盆底脱垂病理状态下可能发生的生物力学轴和支撑的变化。基于盆底的生理状态模型，我们通过平衡腹腔内压（IAP）和子宫病理性位置负荷，将子宫模型模拟到病理性位置。在联合损伤的情况下，我们比较了不同 IAP 下不同子宫形态特征位置可能引起的盆底生物力学变化模式。子宫口的方向逐渐从骶尾骨方向变为阴道口的垂直向下，发生较大的向下脱垂位移，阴道后壁呈“下跪”状膨出脱垂。当腹压值为 148.1cmHO 时，正常和病理性盆底系统中宫颈在健康状态下的下降位移分别为 11.94、20、21.83 和 19.06mm，在联合损伤状态下分别为 13.63、21.67、22.94 和 19.38mm。这表明子宫在异常 90°位置的最大宫颈下降位移，可能伴有宫颈-子宫脱垂以及阴道后壁脱垂。盆底的联合力指向阴道口向下脱垂的方向，膀胱和骶尾骨的生物力学支撑逐渐减弱，这可能会加重盆底软组织损伤和生物力学失衡，导致 POP 疾病的发生。
