Dark skin pigmentation can occur anywhere on the body, including the ankles, elbows and inner thighs. This pigmentation can be due to a variety of medical disorders, external complications and skin conditions. Because some of these conditions can be dangerous if you don't treat them, you should understand why pigmentation problems occur and how you can treat them.
Darkened pigmentation on the elbows, ankles and inner thighs can be the result of liver spots. Liver spots, also called solar legumes or age spots, occur when excess sun exposure causes melanin, a pigment in the skin, to clump together. Hyperpigmentation can also be due to skin conditions such as acne or ingrown hairs. In addition, physical trauma to the skin can darken the skin. Some medical conditions such as Addison's disease and primary biliary cirrhosis can alter the skin's color as well.
Over-the-counter and prescription skin bleaches can help eliminate dark pigmentation of the skin. These creams typically contain hydroquinone, tretinoin or cortisone and can take up to six weeks to work. A doctor can also perform a variety of procedures to remove the pigmented layer of skin. Laser therapy, dermabrasion and chemical peels all slough away unwanted darkened skin using chemicals or a rapidly spinning brush. Cryotherapy involves freezing and removing the pigmented skin with liquid nitrogen.
Because the sun can exacerbate and sometimes even cause pigmentation problems, the Mayo Clinic suggests limiting outdoor time. Try to stay out of the sun between 10 o'clock in the morning and 4 o'clock in the evening when the sun is strongest. Always wear a broad-spectrum sunscreen that protects your skin from both types of ultraviolet radiation: UVA and UVB. For maximum protection, apply the sunscreen about 30 minutes before you go into the sun.
Although pigmentation problems are not usually cause for alarm, you should contact a doctor or dermatologist if you notice that the spots are sore, bleed, change in size, are multiple colors, have irregular shaped borders or are darkly pigmented. These could be signs of melanoma, a dangerous form of skin cancer that can damage skin tissue and spread throughout the body. To minimize risk, examine your skin monthly.