Comparative Analysis of Anisotropic Tensile Strength of Human Abdominal Skin

The mechanical properties of human skin have been investigated for decades, yet studies using fresh human tissue remain limited. In this study, we examined the anisotropic behavior of human abdominal skin by assessing tensile strength in panniculectomy specimens obtained from eight female patients. Rectangular 7-mm–long skin samples (0.5, 1.0, and 1.5 cm widths) were excised from each pannus specimen and subjected to uniaxial dynamic tensometry, with the long axis oriented either parallel or perpendicular to Langer’s lines. Samples tested parallel to Langer’s lines exhibited a 2- to 3-fold greater maximum load capacity compared with those tested perpendicular. No statistically significant correlation was detected between tensile strength and body mass index (BMI), skin thickness, or age. Histology confirmed that higher tensile strength occurred when dermal collagen fibers were aligned parallel to the direction of the applied load. These findings demonstrate that collagen orientation strongly influences the mechanical behavior of human skin, with implications for surgical planning, implantable prosthetic design, and wound healing.