According to the National Pressure Injury Advisory Panel (NPIAP) staging system, a Stage 3 pressure injury is defined as full-thickness loss of skin. In this stage, adipose (subcutaneous) tissue is visible in the ulcer, and granulation tissue and epibole (rolled wound edges) are often present. The damage extends through the dermis into the subcutaneous tissue, but the underlying fascia, muscle, tendon, or bone are not exposed. Slough or eschar may be present but do not obscure the depth of tissue loss.

A. Persistent focal edema without skin breakage is characteristic of a suspected Deep Tissue Injury (DTI), not a Stage 3 ulcer.

C. Exposed muscle, tendon, or bone signifies a Stage 4 pressure injury, which represents full-thickness skin and tissue loss.

D. Partial-thickness skin loss involving the epidermis and/or dermis, presenting as a blister or shallow crater, defines a Stage 2 pressure injury.

1. Edsberg, L. E., Black, J. M., Goldberg, M., McNichol, L., Moore, L., & Sieggreen, M. (2016). Revised National Pressure Ulcer Advisory Panel Pressure Injury Staging System: Revised Pressure Injury Staging System. Journal of Wound, Ostomy and Continence Nursing, 43(6), 585–597. https://doi.org/10.1097/WON.0000000000000281 (Table 1 provides the official definition for a Stage 3 Pressure Injury: "Full-thickness loss of skin, in which adipose (fat) is visible...")

2. National Pressure Injury Advisory Panel (NPIAP). (2016). Pressure Injury Stages. Retrieved from the NPIAP website. The official guidelines define Stage 3 as "Full-thickness skin loss. Adipose (fat) is visible in the ulcer and granulation tissue and epibole (rolled wound edges) are often present...Fascia, muscle, tendon, ligament, cartilage and/or bone are not exposed."