Measurement of the Mechanical Properties of the Human Kidney

The kidney plays an important role by filtering of all the blood in the body. Mechanical loading as a result of accident or any kind of trauma can disrupt the normal function of the kidney. Since the abdominal injuries these days are on the rise, understanding the mechanical response of the kidney, as one of the most important organs in the abdomen, is of great interest to design of protective equipment as well as preventive measures. Therefore, the precise reliable mechanical properties of the human kidney are a crucial tool for the biomechanical analyses of such conditions. However, so far almost all the reported results on the mechanical properties of the kidney are related to the animals and there is a paucity of knowledge on the mechanical properties of the human kidney. Hence, this study was aimed at experimentally measuring the axial and transversal mechanical properties of the human kidney under the tensile loading. To do that, the kidney of 20 human cadavers was excised during the autopsy and histologically analyzed to extract the mean angle of collagen fibers. Thereafter, the samples were cut and subjected to a series of axial and transversal tensile loadings. The results revealed the tensile elastic modulus of 180.32 +/- 11.11 kPa (Mean +/- SD) and 95.64 +/- 9.39 kPa under the axial and transversal loadings, respectively. Correspondingly, the maximum/failure stresses of 24.46 +/- 3.14 kPa and 31.00 +/- 5.06 kPa were observed under the axial and transversal loadings, respectively. The kidney showed a significantly (p < 0.01, post hoc Scheffe method) higher elastic modulus under the axial loading compared to the transverse one. In addition, a significantly (p < 0.05, post hoc Scheffe method) higher maximum/failure stress was observed under the transverse loading compared to the axial one. The findings of the current study have implications not only for understanding the mechanical properties of the human kidney tissue under axial and transversal tensile loadings, but also for providing a raw data for both the doctors and engineers to be used for diagnosis and simulation purposes as well as tissue engineering. (C) 2017 AGBM. Published by Elsevier Masson SAS. All rights reserved.