What is the definition or description of: bed sore?

Bed Sores: A bed sore is an injury to the skin, and tissues beneath the skin, caused by pressure. They can range from a stage one pressure sore (tender, red and does not blanch) to stage four (an open wound extending down to the bone). Early stage pressure sores can respond to off-loading, while deep ulcers require debridement, dressing changes and sometime surgery.

Pressure ulcer: Bed sores are pressure related wounds or sores - usually from prolonged immobilization. This can occur with traumatic injuries, spinal cord injuries, or prolonged illness that results in being bed ridden. It is a combination of pressure, blood supply interruptions, and immobilization.