What is a key characteristic of a Stage 4 pressure ulcer?

A key characteristic of a Stage 4 pressure ulcer is the exposure of underlying structures such as tendons, muscles, or even bone. This stage represents the most severe form of pressure injury, where significant tissue loss has occurred, often resulting in deep wounds that reach through the dermis and into the subcutaneous tissue. The presence of exposed structures indicates that the ulcer has progressed well beyond superficial skin layers, showcasing serious damage requiring extensive medical attention.

In contrast, partial thickness skin loss is indicative of earlier stages of pressure ulcers, where only the epidermis or part of the dermis is affected. The exposure of subcutaneous tissue alone, while serious, does not encompass the full extent of the damage seen in Stage 4 ulcers. Intact skin would not be characteristic of any pressure ulcer, as the definition of pressure ulcers inherently involves some level of skin damage. Thus, understanding the severity and characteristics of each ulcer stage is crucial for effective treatment and prevention strategies.