mr. gonzalez, an 82-year-old man, fell down three weeks ago and broke his leg. he has been living at shady grove nursing home for the past two years. his family only visits him every 2-3 months. mr. gonzalez has been confined to the bed. the staff have been ignoring him lately; they don't move him hardly at all sometimes for 24 hours. at first the skin on his buttocks was shiny and red, but progressed to a shallow open sore. there is no sign of infection. based on the most probable diagnosis, can the doctor make this diagnosis just on the visual examination of his skin alone?