Here, collagen fibers reorganize, the tissue remodels and matures and there is an overall increase in tensile strength (though maximum strength is limited to 80% of the pre-injured strength). The Proliferative phase often lasts anywhere from four to 24 days.ĭuring the Maturation phase, the new tissue slowly gains strength and flexibility. In the third stage, epithelial cells arise from the wound bed or margins and begin to migrate across the wound bed in leapfrog fashion until the wound is covered with epithelium. During contraction, the wound margins contract and pull toward the center of the wound. The Proliferative phase features three distinct stages: 1) filling the wound 2) contraction of the wound margins and 3) covering the wound (epithelialization).ĭuring the first stage, shiny, deep red granulation tissue fills the wound bed with connective tissue, and new blood vessels are formed. Once the wound is cleaned out, the wound enters Phase 3, the Proliferative Phase, where the focus is to fill and cover the wound. This phase often lasts four to six days and is often associated with edema, erythema (reddening of the skin), heat and pain. These cells also secrete growth factors and proteins that attract immune system cells to the wound to facilitate tissue repair. As the white blood cells leave, specialized cells called macrophages arrive to continue clearing debris. These cells often reach their peak population between 24 and 48 hours after injury, reducing greatly in number after three days.
Healing begins with Hemostasis.ĭuring Phase 2, a type of white blood cells called neutrophils enter the wound to destroy bacteria and remove debris. If Phase 1 is primarily about coagulation, the second phase, called the Defensive/Inflammatory Phase, focuses on destroying bacteria and removing debris-essentially preparing the wound bed for the growth of new tissue. An enzyme called thrombin is at the center, and it initiates the formation of a fibrin mesh, which strengthens the platelet clumps into a stable clot. During this process, platelets come into contact with collagen, resulting in activation and aggregation. In this phase, the body activates its emergency repair system, the blood clotting system, and forms a dam to block the drainage. Hemostasis, the first phase of healing, begins at the onset of injury, and the objective is to stop the bleeding.
The cascade of healing is divided into these four overlapping phases: Hemostasis, Inflammatory, Proliferative, and Maturation.
Fhe 12 stages of healing skin#
When the skin is injured, our body sets into motion an automatic series of events, often referred to as the “cascade of healing,” in order to repair the injured tissues. The body is a complex and remarkable machine, and the dynamic process of wound healing is a great example of how our body’s different systems, along with the proper wound care products, work together to repair and replace devitalized tissues.