Which feature indicates a Stage 4 pressure injury?

Which feature indicates a Stage 4 pressure injury?

• A. Only epidermis damaged
• B. Intact skin with redness
• C. Slough covering wound
• D. Bone, muscle, or tendon visible; full-thickness tissue loss.

Answer: (D)

Understanding pressure injury depth is key here. Stage four represents the deepest level of tissue loss, where the damage is full-thickness and reaches underlying structures. The defining feature is exposed bone, tendon, or muscle, indicating the wound has gone through all skin layers and subcutaneous tissue. Slough or eschar can be present at this stage, and undermining or tunneling may occur, but the critical indicator is the visibility of these deeper structures. Other descriptions describe less severe or different scenarios. Damage confined to the epidermis or a non-bleeding red area corresponds to earlier stages, and a wound with slough but without exposed bone, tendon, or muscle does not by itself confirm stage four.

Understanding pressure injury depth is key here. Stage four represents the deepest level of tissue loss, where the damage is full-thickness and reaches underlying structures. The defining feature is exposed bone, tendon, or muscle, indicating the wound has gone through all skin layers and subcutaneous tissue. Slough or eschar can be present at this stage, and undermining or tunneling may occur, but the critical indicator is the visibility of these deeper structures.

Other descriptions describe less severe or different scenarios. Damage confined to the epidermis or a non-bleeding red area corresponds to earlier stages, and a wound with slough but without exposed bone, tendon, or muscle does not by itself confirm stage four.