Diseases of the nails

AL Wright

In animals and birds claws are used for digging and grasping as well as for fighting. The human nail may be used as a weapon but its main function is to protect the distal soft tissues of the fingers and toes.

As an ectodermal derivative composed of keratin, the nail plate grows forward from a fold of epidermis over the nail bed which is continuous with the matrix proximally. The keratin composing the nail is derived mainly from the matrix with contributions from the dorsal surface of the nail fold, and the nail bed also adds keratin to the deep surface.

The nail grows slowly for the first day after birth then more rapidly until it slows in old age. The rate of nail growth is greater in the fingers than the toes, particularly on the dominant hand. It is slower in women but increases during pregnancy. Finger nails grow at approximately 0-8 mm per week and toe nails 0-25 mm per week.

Section through finger showing nail structure
How To Reduce Acne Scarring

How To Reduce Acne Scarring

Acne is a name that is famous in its own right, but for all of the wrong reasons. Most teenagers know, and dread, the very word, as it so prevalently wrecks havoc on their faces throughout their adolescent years.

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