Mechanical analyses on urethra wall after suburethral slings for female pig stress urinary incontinence / 第三军医大学学报

ABSTRACT

Objective To analyze the mechanical mechanism of suburethral slings by measuring the mechanical properties of female pig urethra wall and polypropylene mesh.Methods The uniaxial tension tests of 49 female pig urethra wall strips and 27 polypropylene mesh samples were performed to test the mechanical properties.Results The stress and strain of urethra wall displayed a parabola shape and its elastic modulus was proportional to the square root of stress as well as the strain.The maximum calculated elastic moduli of the urethra wall were 0.806 MPa and 0.818 MPa correspondingly calculated with stress and strain.The elastic modulus of polypropylene mesh was(6.977?1.095) MPa.The ultimate stress of polypropylene mesh was significantly higher than that of the urethra wall,and the ultimate strain of polypropylene mesh was significantly lesser than that of the urethra wall.The calculation results suggested that the suburethral slings treatment of poly-propylene mesh decreased the deformation to 1/3 of the untreated stress urinary incontinence.Conclusion Polypropylene mesh has special mechanical properties that suit suburethral slings and enhance the support to the urethra,and improve the continence.