Board Review: Wound Healing Phases

Overview / Definition Wound healing is defined as the biological process of tissue repair following injury. It involves a series of coordinated events that restore the integrity of the skin and underlying tissues. The process can be categorized into four primary phases: hemostasis, inflammation, proliferation, and remodeling. Epidemiology Wound healing is a universal process affecting individuals across all demographics. The incidence of wounds varies based on factors such as age, comorbidities, and environmental conditions. Key statistics include: Approximately 2% of the population experiences chronic wounds, particularly among the elderly and those with diabetes. Incidence of surgical wounds and traumatic injuries is significant in urban settings, with thousands of cases reported annually. Pathophysiology / Mechanism The wound healing process involves a complex interplay of cellular and molecular mechanisms: Hemostasis: Immediately after injury, blood vessels constrict, and platelets aggregate to form a clot, preventing further bleeding. Inflammation: Inflammatory cells migrate to the wound site, releasing cytokines and growth factors that initiate healing. Proliferation: Fibroblasts and endothelial cells proliferate, leading to new tissue formation, angiogenesis, and re-epithelialization. Remodeling: Collagen maturation and reorganization occurs over weeks to months, restoring tensile strength to the tissue. Clinical Presentation Clinically, wounds can present in various forms, including: Acute wounds: Surgical incisions, traumatic injuries. Chronic wounds: Non-healing ulcers, pressure sores, diabetic foot ulcers. Signs of inflammation: Redness, swelling, heat, and pain at the wound site. Diagnosis / Workup Diagnosis primarily involves a thorough clinical assessment, which may include: History-taking: Duration, type of injury, comorbidities, and wound care history. Physical examination: Inspecting wound characteristics, size, depth, and signs of infection. Labora