There are many types of chronic wounds, and each type has different characteristics – some are painful and some are not; some have a round appearance while others are irregular …… Here we focus on the four most common types of chronic wounds These are venous stasis ulcers, diabetic ulcers, pressure ulcers, and postoperative or traumatic ulcers. Venous stasis ulcers, which usually occur in the lower leg, are the main type of chronic trauma and occur mainly in the elderly. It occurs mainly because of a malfunction of the venous valves that prevent the return of blood. Simply put, veins have unidirectional valves that ensure blood flow back to the heart, but in venous insufficiency, damage to the valves leads to increased blood reflux and stagnation in the venous bed, resulting in leakage of body fluids from the veins into the tissue spaces, causing tissue damage and affecting wound healing. Risk factors for venous stasis ulcers. Diabetic ulcers Diabetic ulcers are a major complication of diabetes, with approximately 15% of people with diabetes developing diabetic ulcers during their lifetime. Diabetic ulcers are caused by poor circulation and neuropathy. Diabetic neuropathy can cause dullness of sensation or decreased ability to feel pain, heat or cold, so diabetic patients with neuropathy can inadvertently develop small wounds, blisters or pressure sores due to dullness of sensation, and these small injuries can lead to ulcers or even amputation if left untreated. Preferred sites for diabetic ulcers include the dorsal aspect of the toes, the head of the metatarsal bones and the heel. Pressure sores can develop from prolonged, localized pressure on the body surface, especially in bony prominences such as the sacrococcygeal, heel, scapula and ankle areas, and often occur in people who are bedridden or have severely limited mobility. When the pressure on the tissue is greater than the intracapillary pressure it will cause a reduction in the local blood supply, leading to tissue damage and ulcer formation. Postoperative or traumatic ulcers This type of wound is usually caused by surgical complications, such as incisional dehiscence due to infection. There are also traumatic wounds that fail to close early that may become contaminated or even infected, often with necrotic tissue present. In both cases, foreign bodies such as surgical sutures, implants, exposed bone, tendons or fascia can complicate wound healing by causing persistent infection, which can evolve into chronic wounds. In conclusion, clinically, there are many types of chronic wounds and they vary in etiology and treatment. For further information on chronic trauma, please stay tuned to this topic.