What are wounds and wound healing?

Pressure sores are mechanical injuries caused by external forces, such as cuts, tears, or impacts; they can also be caused by physical factors such as high or low temperatures or radiation, resulting in burns or scalds; chemical contact with the skin can cause chemical burns; and biological factors such as bacterial, viral, or parasitic infections can also cause skin damage. Furthermore, prolonged pressure leading to impaired blood circulation can also cause pressure sores. The management of a pressure sore depends on its size, depth, location, and the presence of infection, which will determine the appropriate treatment method.

Wound healing refers to a series of pathophysiological processes in which local tissue repairs itself after tissue loss due to the action of injury-causing factors, through regeneration, repair, and reconstruction. Essentially, it is an inherent defensive and adaptive response of the body to tissue and cell damage caused by various harmful factors. This regenerative repair manifests in the restoration of lost tissue structure and can also restore its function to varying degrees. However, the repair of lost tissue cells can be either a 'complete restoration' of the original tissue cells, known as 'regeneration'; or it can be a 'partial restoration'—known as 'repair'—where non-specific connective tissue proliferation replaces the original tissue cells. Nevertheless, the process is the same for both of these different outcomes.