Morphological architecture and distribution of blood capillaries and elastic fibres in the human skin.

This study was undertaken to clarify the morphological features in the blood capillary and elastic fibre distribution of the human skin in terms of susceptibility to pressure sore development. Skin tissues were obtained from bony areas: the sacrum and ischial tuberosity and non-bony area: the centre of the gluteus maximus of 5 aged subjects post mortem for examination using light and scanning electron microscopy. It was observed that the sacral skin had finger-like papillae and underneath the blood capillary loops were most numerous. In the ischial skin the dermal papillae consisted of a combination of finger-like and trapezoid shapes having moderate density of blood capillaries. In contrast, the dermal papillae in the gluteal skin were almost flat, so that the blood capillaries were scattered. The size of elastic bundles in the papillary layer of the sacral, ischial and gluteal skin ranged from 2 to 3 microns, 5 to 10 microns, and 3 to 5 microns, respectively. The elastic fibres were densely distributed in the ischial skin while less so in the sacral skin.