Rete ridge

Rete ridge
Details
System	Integumentary system
Function	Increases surface area for attachment
Identifiers
TA98
TH	{{#property:P1694}}
TE	{{#property:P1693}}
FMA	{{#property:P1402}}
Anatomical terminology

The rete ridges, also known as rete pegs, are epithelial extensions that project into the underlying connective tissue in the skin. These structures are a key component of the epidermis, the outermost layer of the skin, and play a crucial role in the structural integrity and function of the skin.

Structure

Rete ridges are formed by the downward projections of the stratum basale, the deepest layer of the epidermis. These projections interdigitate with the upward projections of the dermal papillae, which are part of the dermis, the layer of skin beneath the epidermis. This interlocking structure increases the surface area for attachment between the epidermis and dermis, enhancing the mechanical stability of the skin.

Function

The primary function of rete ridges is to anchor the epidermis to the dermis, providing resistance to shear forces that can cause the layers to separate. This is particularly important in areas of the body that experience significant mechanical stress, such as the palms of the hands and the soles of the feet.

Rete ridges also play a role in the distribution of nutrients from the dermal blood supply to the avascular epidermis. The increased surface area provided by the rete ridges allows for more efficient diffusion of nutrients and waste products between the two layers.

Clinical Significance

Changes in the morphology of rete ridges can be indicative of various skin conditions. For example, in psoriasis, the rete ridges are often elongated and thickened, contributing to the characteristic appearance of the skin in this condition. In contrast, in lichen planus, the rete ridges may become flattened or even absent.

The study of rete ridges is also important in dermatopathology, where the pattern and structure of these projections can aid in the diagnosis of skin diseases.

Also see

• Epidermis
• Dermis
• Stratum basale
• Dermal papillae
• Psoriasis
• Lichen planus