Structure and Function of the Claw and Footpad in Cats
By: Virginia Wells
What Are the Claw and Footpad?
Claws are appendages at the extremities of the digits of cats. The footpads are the tough spongy pads of thick skin beneath each foot.
Where Are the Claw and Footpad Located?
Cats' claws are attached to the last bone of each toe. Footpads are located on each digit, under the metacarpal- and metatarsal-phalangeal joints, and under the segment of the limb between the radius and the ulna (wrist) of cats.
What Is the General Structure of the Claw and Footpad?
The shape of the claw is sickle-like with a needle sharp tip and is designed to allow the cat to grip his prey and hold onto it. Unique in the animal kingdom in design, cats' claws grow continuously and are kept from growing too long through use. Cats maintain the sharp tips by retracting their claws into a skin pouch while walking; this avoids excessive wear and tear.
The claws of a cat are protected by a layer of modified skin, a hard protein cuticle and keratin. Claws grow from within, much like an onion, and the outer worn layers are shed. In fact, your cat's scratching behavior helps the outer layer to loosen from the cuticle and fall off and remain behind at the scratching post.
Cats' footpads are thick and smooth with sweat glands located between their footpads. The hypodermis contains large amounts of adipose tissue.
What Are the Functions of the Claw and Footpad?Claws are also unique in function. They allow the cat to climb, dig, defend himself, fight and attack prey.
The cat's footpads act as shock absorbers for jump-landings and other aerial acrobatic feats. They also enable the cat to walk quietly. The thick pads on the paws insulate the feet and serve as the "housing" for retracted claws.
What Are the Common Diseases of the Claw and Footpad?Among common diseases of the claw and footpad are:
Onychomycosis is fungal disease of the claws in which the claws become misshapen, discolored, thickened and friable.
Onychogryphosis is abnormal hypertrophy and curving of the claws.
What Types of Diagnostic Tests Are Used to Evaluate the Claw and Footpad?
Skin scrapings
X-rays,
Fungal cultures
Biopsy
