1. Diabetic Foot Ulcers (DFU)—Diabetic foot ulcers are a significant problem on a global basis. Approximately 15% of people with diabetes will develop a foot ulcer and it is estimated that more than half of these will experience a second ulcer. Diabetic foot ulcers occur most commonly due to neuropathy (loss of sensation in the lower extremity) and peripheral vascular disease. Neuropathy can occur partially as a complication of prolonged glucose elevation ^{(Steed 2007)} Failure of diabetic foot ulcers to heal may result in amputation.

The main reasons for diabetic foot ulcers failing to heal are two-fold. One primary cause is that the person with the foot ulcer continues to walk on the ulcer causing irritation and skin breakdown. They may also have some type of foreign body enter the skin and be unaware of this happening. For the healing process to take place, these wounds usually have weight redistributed away from the wound in what is known as offloading. Specialty shoes and devices are available to assist with this process.

The second main reason that these ulcers fail to heal is related to proper diabetes control. Uncontrolled blood sugar can prevent the body from healing itself by preventing certain healing process from occurring. Management includes prevention of weight bearing (off loading) , debridement of devitalized tissue, prevention of infection and local wound management.

2. Venous Ulcers—Venous Ulcers are the most common and costly chronic wound ulcer seen in the United States and affect women three times more often than men. The prevalence of lower limb ulcers ranges from 0.12% to 0.32% of the general population. ^{(Burrows 2006)} Patients experiencing venous ulcers suffer from the inability to heal and the high rate of reoccurrence at 72%. ^{(Sibbald 2006)} Venous ulcers can cause pain, limit activities of daily living and negatively impact quality of life.

Venous ulcers can be caused by damaged or leaky venous valves, or a faulty calf muscle pump action which causes to sustained high venous pressure known as venous hypertension. These ulcers are usually located around the medial malleolus and are accompanied by edema or swelling of the affected leg, large amounts of drainage, and often have a scaly type of skin condition known as dermatosis. It is important to note that not all leg ulcers are venous in origin particularly those ulcers located above or below the gaiter and ankle region.

People with venous insufficiency sometimes report having had a blood clot in the affected limb. Due to the interruption of blood flow back to the heart, pooling of blood is seen in the limb that sometimes results in swelling. Eventually, protein from blood vessels can leak into the tissue and cause an ulcer to form. A cornerstone of treatment for venous ulcers beyond local ulcer management is the use of sustained compression in order to decrease the edema by wrapping the legs to promote blood flow back to the heart.

3. Pressure Ulcers—Pressure ulcers are also known as decubitus ulcers or bed sores have a psycologic, physiologic and economic impact on the individual. Pressure ulcers can result from immobility and can occur in persons that are bed ridden, who have had a spinal cord injury, or are in a wheelchair. Prevalence and incidence across all care settings varies ranging from 0.4%-38% in general acute care, 2.2% to 23.9% in long term care, and 0% to 17% in home care. ^{(Source: Weir 2007)} The tissue injury that occurs sometimes is a result of sustained pressure to a bony prominence area such as the hip or heel. The sustained pressure prevents adequate blood flow and causes the tissue to die.

The wounds often fail to heal for a variety of reasons. One main reason is that pressure is not relieved from the wound. Special mattresses, bed and seating cushions are designed to help to relieve pressure to allow better blood flow to the injured area. Other reasons for these wounds to fail to heal often have to do with other underlying medical conditions that affect individuals, such as poor nutrition and incontinence, shear and friction. Pressure ulcer management includes pressure relief/pressure reduction, proper positioning, prevention of infection and local wound management.