Stage II: There is partial-thickness skin loss involving the...

Stage I: The skin is intact with the presence of non-blanchable erythema

Stage III: There is a full-thickness loss of skin that extends to the subcutaneous tissue but does not cross the fascia beneath it

Stage IV: There is full-thickness skin loss extending through the fascia with considerable tissue loss. There might be possible involvement of the muscle, bone, tendon, or joint

Unstageable