The Pressure Ulcer Scale for Healing Sores

Page content

The Current Pressure Ulcer Scale

The National Pressure Ulcer Advisory Panel (NPUAP) in conjunction with the European Pressure Ulcer Advisory Panel (EPUAP) has created the most commonly used pressure ulcer scale for healing sorse. A pressure ulcers is a sore an area of the skin, generally over a bony bump, induced by pressure is applied to the area, or pressure along with a shear.

The pressure ulcer scale is used to describe how much tissue loss has occurred from the pressure ulcer, organizing the sores into different categories which allows for quick and consistent care and treatment.

Pressure ulcers start with a deep tissue injury before advancing into a Stage I, II, III or IV pressure ulcer.

Suspected Deep Tissue Injury

Pressure ulcers begin with an area of the skin that is maroon or purple-colored, possibly with a blister filled with blood or discolored unbroken skin that has been injured by shear and/or pressure. If the patient has dark skin, the deep tissue injury may be hard to see.

Stage I

A Stage I pressure sore has unbroken skin with a redness that is not pale in a small area typically over a bony bump. If the person is dark skin toned, it may not have noticeable paling, but the skin may look different than the skin around it. The pressure ulcer may be soft, firm, painful and cooler or warmer than the skin next to it.

Stage II

Stage II sores are a partial thickness dermis loss that appears as an open, shallow ulcer with a pinkish-red wound bed with no slough. A blister that is either torn or intact and filled with serum may also be present.

Stage III

Stage III is distinguished by full-thickness loss of tissue. Tendon, bone or muscle is not visible, although subcutaneous fat may be revealed. Additionally, even though it will not block out the tissue loss depth, slough may be visible and it might consist of tunneling and undermining. It depends on where the pressure ulcer is located as to the stage III depth. Stage III ulcers can be shallow in the location of the ear, nose, malleolus and occiput since they do not have any subcutaneous tissue.

Stage IV

A stage IV pressure ulcer is described as full thickness loss of tissue with muscle, tendon, or bone revealed. On some parts of the wound bed, eschar or slough may be revealed and usually includes tunneling and undermining. Just like stage III ulcers, stage IV ulcers can also be shallow in the location of the ear, nose, malleolus and occiput since they do not have any subcutaneous tissue. Stage IV ulcers can also spread into muscle and/or sustaining parts such as the tendon, joint capsule, or fascia causing potential osteomyelitis. Bone and/or tendon are revealed or openly conspicuous.


This stage is described as full thickness tissue loss where the foundation of the ulcer is enveloped by slough which can be brown, green gray, yellow or tan and/or eschar which is black, tan, or brown in the bed of the wound. The correct depth of the wound cannot be established until the slough and/or the eschar is eliminated to reveal the foundation of the ulcer.


National Pressure Ulcer Advisory Panel’s New Pressure Ulcer Staging System: The Updated Staging System. (2007). Retrieved November 28, 2010, from MedScape for Medical Students:

Staging Pressure Ulcers. (2009). Retrieved November 28, 2010, from National Presure Ulcer Advisory Panel: