Skin is a remarkable structure. Skin is
actually the single largest organ in the human body. Estimates of the area
that the human skin covers range up to 15,000 sq. inches, or roughly the size of
a 9'x12' rug. The average man has approximately ten pounds of skin and the
average woman, seven pounds.
Skin functions as a bi-directional barrier
meaning that it keeps the good things in and the bad things out. Skin
holds in water and protects us from our environment shielding us from radiation,
chemicals, microorganisms and physical trauma.
When man (and woman) assumed an upright gait, a
significant burden was placed upon the skin of the lower extremity.
There's a number of unique conditions of the skin that are seen specific to the
feet and legs that are due to weight bearing and are found no where else in the
body. The feet and legs will endure more trauma than any other part of our
body resulting in infections, cuts, and scrapes, corns, calluses, etc. The
feet are also a common site for thermal injuries such as frostbite.
The science of dermatology can be somewhat
complicated, but for our interests, let's consider that the skin consists of
three basic layers; the outer layer or epidermis, the middle layer or dermis and
the inner layer referred to as hypodermis. Each of these layers provides a
specific function and is in a constant state of change. For instance, the
epidermis, or outer layer of the skin, is completely replaced once every 28
days. The 28 day turn over is influenced by many factors such as
hydration, friction, sun exposure and a host of other environmental
issues.
The skin of the foot is unique in many
regards. The skin found on the plantar surface (bottom) of the foot,
referred to as glabrous skin, is a very thick form of skin. Glabrous skin
also contains 4-5 times the normal number of sweat glands, lacks hair follicles
and sebaceous glands that would normally lubricate the hair. The skin on
the dorsum (top) of the foot is also unique and is referred to as hairy skin.
This is skin much like what we would see on the majority of the body such as the
arms and legs.
For additional articles relating to skin and skin
problems of the foot, please refer to the Foot and Ankle Knowledge Base.
Skin is a remarkable structure. Skin is
actually the single largest organ in the human body. Estimates of the area
that the human skin covers range up to 15,000 sq. inches, or roughly the size of
a 9'x12' rug. The average man has approximately ten pounds of skin and the
average woman, seven pounds.
Skin functions as a bi-directional barrier
meaning that it keeps the good things in and the bad things out. Skin
holds in water and protects us from our environment shielding us from radiation,
chemicals, microorganisms and physical trauma.
When man (and woman) assumed an upright gait, a
significant burden was placed upon the skin of the lower extremity.
There's a number of unique conditions of the skin that are seen specific to the
feet and legs that are due to weight bearing and are found no where else in the
body. The feet and legs will endure more trauma than any other part of our
body resulting in infections, cuts, and scrapes, corns, calluses, etc. The
feet are also a common site for thermal injuries such as frostbite.
The science of dermatology can be somewhat
complicated, but for our interests, let's consider that the skin consists of
three basic layers; the outer layer or epidermis, the middle layer or dermis and
the inner layer referred to as hypodermis. Each of these layers provides a
specific function and is in a constant state of change. For instance, the
epidermis, or outer layer of the skin, is completely replaced once every 28
days. The 28 day turn over is influenced by many factors such as
hydration, friction, sun exposure and a host of other environmental
issues.
The skin of the foot is unique in many
regards. The skin found on the plantar surface (bottom) of the foot,
referred to as glabrous skin, is a very thick form of skin. Glabrous skin
also contains 4-5 times the normal number of sweat glands, lacks hair follicles
and sebaceous glands that would normally lubricate the hair. The skin on
the dorsum (top) of the foot is also unique and is referred to as hairy skin.
This is skin much like what we would see on the majority of the body such as the
arms and legs.
For additional articles relating to skin and skin
problems of the foot, please refer to the Foot and Ankle Knowledge Base.
