Stage II: Partial-thickness skin loss involves epidermis and/or dermis. Ulcer is superficial and presents clinically as an abrasion, blister, or shallow crater.

• 二期：部分皮肤层丢失累及表皮和/或真皮。浅表性溃疡。临床表现为擦伤、水泡、或浅表溃疡龛（火山口状溃疡）。