Institute for Mechanical Systems, ETH Zürich, Zurich, Switzerland.
Department of Obstetrics and Gynecology, University Hospital of Zurich, Zurich, Switzerland.
Ann Biomed Eng. 2024 Jun;52(6):1576-1590. doi: 10.1007/s10439-024-03472-6. Epub 2024 Feb 29.
Supraphysiological stretches are exploited in skin expanders to induce tissue growth for autologous implants. As pregnancy is associated with large levels of sustained stretch, we investigated whether skin growth occurs in pregnancy. Therefore, we combined a mechanical model of skin and the observations from suction experiments on several body locations of five pregnant women at different gestational ages. The measurements show a continuous increase in stiffness, with the largest change observed during the last trimester. A comparison with numerical simulations indicates that the measured increase in skin stiffness is far below the level expected for the corresponding deformation of abdominal skin. A new set of simulations accounting for growth could rationalize all observations. The predicted amount of tissue growth corresponds to approximately 40% area increase before delivery. The results of the simulations also offered the opportunity to investigate the biophysical cues present in abdominal skin along gestation and to compare them with those arising in skin expanders. Alterations of the skin mechanome were quantified, including tissue stiffness, hydrostatic and osmotic pressure of the interstitial fluid, its flow velocity and electrical potential. The comparison between pregnancy and skin expansion highlights similarities as well as differences possibly influencing growth and remodeling.
超生理拉伸被用于皮肤扩张器中，以诱导组织生长用于自体植入物。由于妊娠与大量持续拉伸有关，我们研究了妊娠期间是否会发生皮肤生长。因此，我们结合了皮肤的力学模型和对五名不同妊娠阶段的孕妇身体多个部位进行的抽吸实验的观察结果。测量结果显示皮肤的硬度持续增加，最后三个月观察到的变化最大。与数值模拟的比较表明，测量到的皮肤硬度增加远低于腹部皮肤相应变形所预期的水平。一组新的考虑到生长的模拟可以使所有观察结果合理化。预测的组织生长量与分娩前大约 40%的面积增加相对应。模拟的结果还提供了研究妊娠期间腹部皮肤中存在的生物物理线索的机会，并将其与皮肤扩张器中的线索进行了比较。量化了皮肤力学的变化，包括组织硬度、细胞外间质液的静水和渗透压、其流速和电势。妊娠和皮肤扩张的比较突出了相似之处和差异，这些可能影响生长和重塑。
