Surgery, the branch of medicine concerned with the treatment of injury, disease, and other ailments by manual and instrumental means. Surgery involves the treatment of acute injuries and diseases, as opposed to chronic, slowly progressive diseases, unless patients with the latter diseases must undergo surgery.
There are four main categories of surgery: wound treatment, extirpative surgery, reconstructive surgery, and transplant surgery. The technical aspects of wound surgery, which focus on achieving good healing and avoiding infection. Extirpative surgery involves removing diseased tissue or organs. Cancer surgery often falls into this category, and the most common surgeries include mastectomy (removal of the breast), cholecystectomy (removal of the gallbladder), and hysterectomy (removal of the uterus). Reconstructive surgery involves replacing tissue lost through fractures, burns, or degenerative disease processes, especially in orthopedic and orthopedic surgery. Grafts from patients or others are often used to replace lost tissue. Reconstructive surgery also uses artificial devices (prostheses) to replace damaged or diseased organs or tissues. Common examples are the reconstruction of hip joints using metal and the replacement of heart valves with plastic valves. Transplant surgery involves replacing a patient's diseased organ with an organ transplanted from another body. The kidney is the most common transplant organ.