Dermis

The dermis below the epidermis is further divided into two layers.

The papillary layer which helps to prevent shearing of the epidermis on the dermis. The basal cells of the stratum germinativum are anchored into this area.

Diagrams to show shearing mention re: crural sores. This tends to be lost when the skin becomes wet and macerated.

The reticular layer is the main fibrous bed of the dermis, composed of coarse, dense and interlacing collagen fibres intermingled with a few reticular fibres and numerous elastic fibres. These fibres change with age, becoming less elastic so skin if pinched or stretched does not return to normal shape as quickly.

The predominant direction of all fibres is parallel to the surface. Owing to the direction of the fibres, lines of skin tension, Langer's Lines are formed. These are important surgically as incisions made parallel gape less and heal with less scar tissue than incisions made at right angles or obliquely.