Variation in glabrous skin physiology across anatomical locations on the human hand

Abstract Skin physiology varies greatly between anatomical locations, with impact on tactile
sensitivity. Research on the variations in morphology and physiology between different anatomical
locations of glabrous skin is limited so far. This study investigates the morphology and physiology
of glabrous skin on the human hand (N = 60), including the index finger pads of dominant and
non-dominant hand, the small finger pads, the thenar palm and the volar arm as hairy skin reference.
We employed laser scanning microscopy, optical coherence tomography, skin corneometry, skin
cutometry and two-point discrimination measurements as non-invasive in situ methods. We found
significant morphological and physiological differences between fingers, palm and volar arm. The
finger pads had a thicker stratum corneum (SC), especially the index finger of the dominant hand.
They also exhibited higher skin hydration and a higher density of Meissner corpuscles and of
sweat glands compared to the palm. All parameters exhibited strong interindividual variability.
A correlation between anatomical positions for individuals was found for some but not all
parameters. The skin’s mechanical response differed significantly between the anatomical locations,
in correlation with skin hydration for all glabrous skin positions. The effect of ageing on skin elasticity
was strongest on the hairy skin of the volar arm. In glabrous skin ageing affected the density of
Meissner corpuscles and thus spatial acuity. Glabrous skin exhibits a high specialization depending
on the anatomical position. Physiological and morphological parameters play a crucial role in its
mechanical properties and tactile acuity.