Wound

A wound is a disruption of the skin or mucous membranes resulting from a physical injury. Open wounds involve a break in the surface, such as skin cuts or ulcers; closed wounds involve underlying tissues without an obvious opening, such as contusions. Common wound types include abrasions (scrapes), incisions (surgical or clean cuts), lacerations (tearing), punctures, and avulsions (tearing away of tissue). Wounds are also described by depth: superficial (damage to the epidermis), partial-thickness (epidermis and part of dermis), and full-thickness (through the dermis, potentially involving underlying tissues).

Healing proceeds through phases: hemostasis to stop bleeding, inflammation to clear debris and fight infection, proliferation with tissue formation and epithelialization, and remodeling as scar tissue matures. The duration depends on wound type, size, location, blood supply, and host factors like age and diseases (e.g., diabetes). Some wounds become chronic when healing stalls, requiring medical evaluation.

First aid and medical care aim to prevent infection and promote healing. Clean wounds with mild soap and water or saline; avoid harsh scrubbing or antiseptics like iodine or peroxide for routine cleaning. Debridement or wound-care by a clinician may be needed for dead tissue. Dressings should protect and maintain a moist environment unless there is bleeding, and tetanus vaccination should be updated if indicated. Seek medical help for deep, extensive, heavily bleeding wounds, wounds with foreign bodies, signs of infection, or wounds over joints or tendons.

Complications can include infection, delayed healing, dehiscence (reopening), necrosis, and abnormal scarring such as keloids or contractures. Preventive measures include prompt cleaning, moisture-balanced dressings, appropriate closure for surgical wounds, good nutrition, and management of underlying conditions. Wounds may be classified by contamination level (clean, clean-contaminated, contaminated, dirty) to guide treatment decisions.