Cracked heels or heel fissures are a common foot problem. It became painful, unattractive, and very upsetting especially when the cracks are deep; 
the skin bleeds easily and causes a lot of pain. The heel fissures usually occur when the skin becomes dry and aggravates the thick, brittle calluses on the heels. They also develop by placing too much pressure on the heel while walking.
Causes:
There are many causes of cracked heels or heel fissures. Some of the most common causes are inactive sweat glands, dry skin, wearing shoes with an open back, prolonged standing, and surgery to the lower extremities, obesity, high arched feet, flat feet, thyroid disease, improperly fitting shoes, heel spurs, athlete’s foot, psoriasis and diabetes.
Symptoms:
The most common symptoms of cracked heels are the hard growth of skin on the outer edge of the heel, yellow or dark skin on the heel, pain while walking, red or flaky patches on the heel of the foot, Peeling and cracked skin and Itchy skin. In some cases the cracked heels can become infected, and lead to cellulitis. This must be treated with the elevation of the area, debridement of dead tissue, and antibiotics.
The cracked heels became more difficult to treat when the skin around rim of the heel is thick.