Nail Blood and Nerve Supply

A rich supply of nutrients is delivered to the nail unit by the blood. Arteries carry blood from the heart to other parts oft he body. Two arteries supply each nail unit. A single artery runs along each side of the finger passing through the lateral nail fold. After leaving the nail fold, they run deep into the dermis (basement tissue) of the nail bed. Many small branches carry blood from the arteries to other parts of the nail unit. These tiny branches are called capillaries. The capillaries give the nail bed its pinkish color. The capillaries carry blood to the epidermis, just below the nail plate. The result is a healthy pink appearance. The capillaries do not reach into the nail plate. Therefore, the nail plate receives no blood or nutrients. Blood is drained away from the nail unit by veins. Veins collect blood from the capillaries and return it to the heart. The nail unit has two veins. Each lateral nail fold has its own vein. These veins carry blood and waste products away from the nail bed. Figure 1.5 shows the complex system of veins, arteries, and capillaries found in the hand and finger.

Nerves follow a similar path through the nail unit. Nerves provide the sensations of touch, pain, and warmth. They also move the muscles in the fingers and hands. The nerves end near the skin’s surface. The nerve endings are very sensitive. Some are sensitive to pain, some to pressure and others to heat. They relay these sensations back to the brain.