A wound is any damage or break in the surface of the skin. Wounds can be:
- Accidental for example, burns, abrasions, paper cuts, skin tears
- Surgical for example an incision to remove a diseased appendix
- Occur because of underlying disease for example diabetic and vascular ulcers
- Some skin conditions may also develop into a wound for example eczema or psoriasis
Wounds generally fall into two categories: acute and chronic.
Chronic wounds are acute wounds have not progressed through the stages of healing normally. They may heal at a much slower rate, heal only partially or reoccur after partial or complete healing. These chronic wounds are almost always associated with underlying chronic diseases that affect either the blood supply or how the cells function at the wound site. Wounds that take a long time to heal need special care. It is important to not only treat the wound but also diagnose and address the underlying condition causing the wound to minimise risk of further chronic wounds.
Major types of chronic wounds
Any acute wound (eg skin tear, surgical incision) can become chronic if the person has risk factors that impact on wound healing. However there are several types of wounds that account for the majority of chronic wounds. These are:
Also known as bed sores, pressure sores or decubitus ulcers, these wounds are caused by pressure and/or shearing force on the skin. These generally occur in people who have limited mobility due to illness and/or frailty and are unable to regularly move part or all of their body to a different position. The skin on the points of the body with the greatest pressure breaks down and the resultant wounds range from small superficial wounds to large deep wounds the depth of which may extend down to bone.
These ulcers generally begin on the feet and are a result of changes to nerves and circulation in the body caused by diabetes. There are three main types:
- Neuropathic (due to lack of feeling in the foot so that eg a blister from new shoes can get easily infected and go unnoticed because the lack of pain );
- Ischaemic (due to poor blood supply or circulation also called peripheral vascular disease);
- Neuro-ischaemic (due to a combination of both poor circulation and lack of feeling in the foot).
Serious ulcers and infections, if left untreated or even with treatment, may lead to minor (foot or toe) or major (below or above the knee) lower leg amputation. The surgical scar from the amputation is also at risk of becoming a chronic wound for the same reasons listed above. When a person has an amputation the chances of needing another one greatly increase.
A leg ulcer is a wound between the knee and ankle joint that is slow to heal because of problems with the circulation in the leg. They can be
- Arterial, This type of ulcer usually occurs on the foot or the lower part of the leg. They can be small and sometimes deep and often quite painful. They are caused when the arterial blood flow to the area is reduced and often occur among people who have some form of heart disease.
- Venous this type of ulcer occurs around the ankle area. They are shallow and can be painful. They are caused when the veins in the legs are damaged or are not working properly and therefore do not return blood back to the heart as efficiently as they should. They are also called venous stasis ulcers or sometimes varicose ulcers.When a swollen leg is injured the swelling can interfere with normal healing and lead to a venous leg ulcer.
- Mixed ulcer: This ulcer is due to a combination of venous and arterial disease.