Wounds are a lot more than just a scrape or cut – they can be a sign of something bigger going on in the body. Whether it's a traumatic injury, a surgical wound, a chronic issue like diabetic foot ulcers and leg wounds (in particular venous stasis ulcers and arterial ulcers), ischemic wounds (gangrene) and pressure injuries every wound tells a story. And understanding that story is key to unlocking the right treatment.

A wound isn’t simply a surface problem. It’s a complex process of your body trying to heal itself. To make sure the healing process happens as smoothly as possible, it’s essential to understand not only the wound itself but also what’s going on beneath the surface. This means taking a close look at the type of tissue in the wound, the condition of the surrounding skin, and any underlying health conditions that could be affecting the healing process.

When you look at a wound, you’re not just looking at skin – you’re looking at the body’s response to injury. Here’s a guide to understanding the different tissue types found in wounds.

Eschar is necrotic tissue that appears black or dark brown. It can be either dry or moist and often looks thick, sometimes leathery. Dry eschar forms a protective barrier against microbial contamination, which can be beneficial in cases with compromised circulation, such as in peripheral arterial disease or diabetes. However, moist eschar supports bacterial growth, increasing the risk of infection, so it typically needs to be removed (debrided) to promote healing.

In wounds with poor blood supply, less oxygen and fewer nutrients are reaching the wound bed, limiting healing potential. Removing dry eschar in these cases could worsen the wound and lead to infection. Therefore, leaving it in place until further evaluation is often the best approach.

Slough is also necrotic tissue, but it appears yellow, pale, or greenish and forms from infection or damaged tissue. It may indicate that the wound is stuck in the inflammatory phase (common in chronic wounds) or that the body is cleaning up the wound bed to prepare for healing. Slough usually has a moist, shiny, stringy appearance and can be firmly attached to the wound bed.

Granulation tissue is a key player in the healing process, forming during the proliferative phase. It is collagen-rich and fills in the wound after the blood clot from the haemostasis phase is replaced. Healthy granulation tissue is bright red and has a grainy texture because of new blood vessels forming in the tissue. It should be protected to ensure proper epithelialisation (new skin growth) and the complete closure of the wound.

Granulating wounds require sufficient blood flow, a slightly acidic environment, a stable temperature, good control of bacteria, moisture balance, and protection from physical trauma. These factors help ensure that healing continues effectively and without interference.

Hyper-granulation tissue occurs when there’s too much granulation tissue, beyond what’s needed to close the wound. This excess tissue may appear dark red and devitalised or pale, and it can prevent the wound edges from closing, leading to excessive scarring. Causes include prolonged inflammation (due to infection or foreign bodies), excessive use of occlusive dressings, constant rubbing from tubes or dressings, or even allergies to materials. Managing hyper-granulation involves addressing the underlying cause, using appropriate dressings, and possibly applying light pressure or hypertonic dressings to dehydrate the tissue.

Epithelialisation, the final stage of wound healing, is when new skin (epithelium) forms over the wound. This tissue typically appears light pink and grows from the edges or as small islands over the wound. A warm, moist environment, along with protection from irritants and physical damage, is essential to support this final healing phase.

The condition of the skin around a wound, known as the periwound, can provide important insights into the wound’s health and its ability to heal.

Signs like maceration, inflammation, erythema (redness), heat, oedema (swelling), induration (hardening), and pain can indicate that the wound is struggling to heal and may be at risk of becoming chronic.

The surrounding skin may also offer clues about the underlying cause of the wound. Dystrophic skin changes such as abnormal pigmentation (haemosiderin stain), varicosities, atrophie blanche (white, scar-like tissue), and lipodermatosclerosis (a firm, woody texture) can signal peripheral venous disease.

By understanding the tissue types involved in a wound and their role in healing, healthcare providers can make informed treatment decisions, creating a tailored plan that ensures the wound heals efficiently and effectively.

A holistic wound assessment helps identify underlying causes and conditions that impact healing, improving health, well-being and outcomes. Accurate wound and patient evaluations provide critical information for effective, evidence-based treatment.

Assessing key aspects, such as tissue type, exudate, and surrounding skin, guides appropriate care and monitors progress. Clear documentation ensures that management plans reflect the wound’s current state, supporting continuity of care and better patient outcomes.