The rigidity of human fingernails: a biophysical investigation on influencing physical parameters

(A) The property of withstanding bending and buckling in a composite material such as the nail is best described by such terms as rigidity or stiffness. (B) The physical property of rigidity can be understood from the macromolecular orientation of the keratin filaments and the cellular architecture of the dorsal and ventral nail plates. (C) The rigidity is influenced by factors such as the water content of the nail material. Specimens investigated must therefore be well equilibrated prior to the measurements. (D) Detergents, organic solvents, oils etc. are factors which are likely to influence nail rigidity.