A Kennedy Ulcer (KU) is often confused with a standard pressure ulcer, or bedsore, because both involve localized tissue injury. A standard pressure ulcer results from prolonged mechanical pressure, shear, or friction over a bony prominence. The Kennedy Ulcer (KTU) is a specific, rapidly developing skin breakdown that occurs during the final stages of life. While sometimes categorized as a pressure injury, the KU is clinically viewed as an unavoidable manifestation of the body’s internal systems shutting down.
How Standard Pressure Ulcers Develop
Standard pressure ulcers are primarily caused by extrinsic forces that compress soft tissue against a bony area for an extended period, leading to localized tissue ischemia. The sustained force restricts blood flow, depriving the affected area of necessary oxygen and nutrients. This localized deprivation causes the tissue to die, resulting in a visible sore.
Friction (the rubbing of skin against a surface) and shear (the sliding of internal tissues over bone while the skin remains stationary) both contribute to this damage. These mechanical forces cause deformation of the blood vessels, leading to occlusion and subsequent cell death. Clinicians use a staging system (Stage 1 through 4) to classify the severity of this mechanical damage, progressing to full-thickness tissue loss.
Distinctive Features of a Kennedy Ulcer
A Kennedy Ulcer is distinguished by its sudden onset and rapid progression, often developing within hours or a few days—a speed rarely seen in a typical pressure injury. This rapid deterioration led to the nickname “3:30 Syndrome,” reflecting its dramatic appearance during a single shift. The most common location is the sacrum, the triangular bone at the base of the spine, though KUs can appear on other pressure points.
The physical appearance is unique, frequently starting as a dark maroon or purple area of discoloration, often resembling a bruise. The shape is highly characteristic, often described as pear-shaped, horseshoe-shaped, or butterfly-shaped, with irregular borders. Unlike a slowly developing pressure ulcer, the Kennedy Ulcer often presents immediately as a deep tissue injury, signifying extensive damage beneath the surface.
The Role of Skin Failure in Ulcer Formation
The difference between a Kennedy Ulcer and a standard pressure ulcer lies in their underlying causes, separating mechanical injury from systemic collapse. A KU is considered a manifestation of “Skin Changes at Life’s End” (SCALE) or “skin failure,” meaning the skin fails due to intrinsic physiological breakdown. As a person nears the end of life, the body prioritizes blood flow to vital organs like the heart and brain.
This shunting of blood away from the skin leads to diminished tissue perfusion and localized hypoxia. Compromised by poor circulation and multi-organ system failure, the skin loses its ability to tolerate even minimal external pressure. The tissue breakdown is caused by the body’s internal inability to sustain skin viability, not solely by external pressure. This distinction indicates a terminal decline, shifting the focus of care from wound healing to comfort and pain management.