In addition to poor circulation, neuropathy, and difficulty moving, factors that contribute to<unk> s include systemic illnesses, age, and repeated trauma. The genetic skin disorders collectively known as epidermolysis bullosa display skin fragility and a tendency to develop<unk> , non-healing wounds. Comorbid ailments that may contribute to the formation of<unk> s include vasculitis (an inflammation of blood vessels), immune suppression, pyoderma gangrenosum, and diseases that cause ischemia. Immune suppression can be caused by illnesses or medical drugs used over a long period, for example steroids. Emotional stress can also negatively affect the healing of a wound, possibly by raising blood pressure and levels of cortisol, which lowers immunity. What appears to be a<unk>  may also be a malignancy; for example, cancerous tissue can grow until blood cannot reach the cells and the tissue becomes an ulcer. Cancer, especially squamous cell carcinoma, may also form as the result of<unk> s, probably due to repetitive tissue damage that stimulates rapid cell proliferation. Another factor that may contribute to<unk> s is old age. The skin of older people is more easily damaged, and older cells do not proliferate as fast and may not have an adequate response to stress in terms of gene upregulation of stress-related proteins. In older cells, stress response genes are overexpressed when the cell is not stressed, but when it is, the expression of these proteins is not upregulated by as much as in younger cells. Comorbid factors that can lead to ischemia are especially likely to contribute to<unk> s. Such factors include<unk>  fibrosis, edema, sickle cell disease, and peripheral artery disease such as by atherosclerosis. Repeated physical trauma plays a role in<unk>  formation by continually initiating the inflammatory cascade. The trauma may occur by accident, for example when a leg is repeatedly bumped against a wheelchair rest, or it may be due to intentional acts. Heroin users who lose venous access may resort to 'skin popping', or injecting the drug subcutaneously, which is highly damaging to tissue and frequently leads to<unk>  ulcers. Children who are repeatedly seen for a wound that does not heal are sometimes found to be victims of a parent with Munchausen syndrome by proxy, a disease in which the abuser may repeatedly inflict harm on the child in order to receive attention. Periwound skin damage caused by excessive amounts of exudate and other bodily fluids can perpetuate the non-healing status of<unk> s. Maceration, excoriation, dry (fragile) skin, hyperkeratosis, callus and eczema are frequent problems that interfere with the integrity of periwound skin. They can create a gateway for infection as well as cause wound edge deterioration preventing wound closure.
Chronic wound
Burn scar contracture
Wound contracture
Implant failure
Cancer cluster
Postoperative wounds
Stab wound
Chronic limb threatening ischemia