tree surgery, practice of repairing damaged trees to restore their appearance and to arrest disease. Injured or diseased parts are first removed (even small cavities in the bark may harbor injurious fungi and insects), the surfaces are treated with antiseptics and healing aids, and the cavity may be filled with cement or some special material, e.g., composition filler or elastic cement. Professional tree surgeons commonly perform many tasks in addition to surgery that are difficult for the individual gardener e.g., large-scale pruning and providing proper support when needed.

surgery, branch of medicine concerned with the diagnosis and treatment of injuries and the excision and repair of pathological conditions by means of operative procedures (see also anesthesia; medicine; radiology).

Early History

In prehistoric times, sharpened flints and other sharp-edged devices were used to perform various surgical operations. Circumcision and other ritualistic operations were later performed with similar instruments. There are indications that in Neolithic times saws of stone and bone were used to perform amputations. Nearly all major operations were performed by the ancient Hindus nearly a thousand years before the advent of Greek medicine. Knowledge of the use of soporific potions to alleviate the pain caused by surgery can be traced to remote antiquity.

The early Greeks and Romans practiced surgery with great skill and with such cleanliness that infection of surgical and other wounds was relatively uncommon. Their cleanliness and their use of boiled water or wine for irrigating wounds was probably suggested by Hippocrates, a competent surgeon and diagnostician of that time. Other notable early surgeons were Erasistratus and Herophilus of the medical school at Alexandria, and Galen, whose numerous treatises were long influential.

The surgical and sanitary techniques employed by the Greeks and Romans were lost with the decline of their civilizations. During the Middle Ages in Europe there was a marked regression in surgical knowledge, and postoperative infection was common. Surgical practice soon fell into the hands of the unskilled and uneducated: the barber-surgeon, who performed the usual functions of a barber as well as surgical operations, became a common figure, especially in England and France. It was not until the 18th cent. that surgery began to reach a professional level. There were, nevertheless, notable figures in early surgery, among them Guy de Chauliac in the 14th cent., and in the 16th cent. Ambroise Paré, who developed sutures and ligatures to stop bleeding and sew up wounds.

The Birth of Modern Surgery

With the introduction of antiseptic methods, surgery entered its modern phase. Louis Pasteur established the fact that microbes are responsible for infection and disease. Using this knowledge, Dr. Ignaz Semmelweis reduced postpartum infections (puerperal sepsis) in the wards of Vienna's lying-in hospitals by urging doctors to wash their hands between patients. In the 1860s Joseph Lister introduced the use of carbolic acid as a cleansing and disinfecting agent, and his results in reducing infection were dramatic. It was found later that the carbolic acid spray that Lister used to cleanse the air about the patient was unnecessary, but the antiseptic treatment of instruments and other articles in contact with the patient continued until antisepsis was gradually replaced by the aseptic methods employed in modern hospitals. Before the discovery of antisepsis by Lister, about 80% of surgical patients contracted gangrene.

Ernst von Bergmann is credited with introducing steam sterilization under pressure for treating instruments and all other medical equipment used for a surgical patient. William Stewart Halsted, the famous surgeon at Johns Hopkins Hospital, introduced sterile rubber gloves when the hands of his fiancée became irritated from constant washings and antiseptics. The development of methods of anesthesia, especially the discovery in the 1840s of the value of ether, has also been of immeasurable value.

Surgery in the Twentieth Century

In the 20th cent., surgery has benefited from an improved understanding of the causes of shock and its treatment; knowledge of blood group typing and transfusion techniques; understanding of blood clotting and the use of anticoagulants; and the development of antibiotics to control infection and analgesics to control pain. Surgical instruments have developed along with modern technology and are now sophisticated, meticulously designed devices. Electrically powered surgical instruments are invaluable for cautery and for separating hard tissues such as bone with minimal damage. Surgical stapling instruments, first developed in the Soviet Union, can join blood vessels or other tissues in less than half the time required by hand stitching. New medical glues, surgical tapes, and even zippers now enable surgeons to close some wounds effectively without stitches. With the development of X-ray techniques and fluoroscopy and, later, CAT scans and magnetic resonance imaging (MRI), surgery gained valuable diagnostic instruments. Some operations are now being conducted inside specially adapted MRI devices, allowing the surgeon to have live images for guidance during operations. Holograms can be created using data from MRI and other diagnostic instruments and are beginning to be used in the operating room to give surgeons a three-dimensional image of the area to be operated upon.

Cryogenic, or supercooled, probe beams have been used to precisely remove tissues and abnormal growths. Ultrasound techniques, using very-high-frequency sound waves, are used to break up kidney stones and are employed in brain and inner-ear operations, which require great precision and control. They are also used to scan the pregnant uterus, a process that, unlike X-ray scanning, does not endanger the fetus. Medical lasers, which produce amplified monochromatic light waves in a very narrowly focused beam, have become useful tools in various forms of surgery, notably that of the eye, and are now commonly used to remove or "spot-weld" tissues.

The heart-lung machine made open-heart surgery possible by taking over the blood-pumping and breathing functions of these organs during operations. Hypothermia, or cold surgery, by which the body is cooled to lower the rate of metabolism, thus reducing the need for oxygen, has made long operations, especially those involving transplantation, possible. Other recent transplantation advances include procedures involving the liver, lungs, pancreas, bone marrow, and the kidney. The first human heart transplant was performed in 1967 by South African surgeon Christiaan Barnard. The usefulness of transplantation is currently limited by the fact that drugs must be used constantly to halt the body's rejection of foreign tissue.

New techniques in orthopedic surgery (see also orthopedics) have also been introduced, including the use of cementing substances to unite bones destroyed by tumor and the replacement of joints with metal or plastic devices. Plastic surgery and reconstructive surgery have made enormous strides, and microsurgery is making severed or injured limbs usable.

A trend toward less invasive surgery and shorter hospital stays began in the 1980s. By 1995 more than 56% of all surgical procedures in the United States were done on an outpatient basis, without an overnight stay in a hospital. Endoscopic surgery, using small incisions and tiny instruments attached to fiber-optic viewing devices (see endoscope), has been used in place of more traditional procedures for gall-bladder surgery, and it has been used on the fetus in the womb to correct life-threatening birth defects before birth. Angioplasty is frequently used to circumvent or postpone the need for coronary artery bypass.

plastic surgery, surgical repair of congenital or acquired deformities and the restoration of contour to improve the appearance and function of tissue defects. Development of this specialized branch of surgery received impetus from the need to repair gross deformities sustained in World War I. By the grafting of tissue or the use of artificial materials such as silicone, some remarkable restorations have become possible. Severe burns and the removal of fairly extensive skin cancers leave scars that must be covered by skin grafts; breast reconstruction after mastectomy is another application.

In addition to correcting a disfigurement, plastic surgery is often needed to restore vital movement and function of tissues that have been destroyed. It is also performed for purely cosmetic purposes, such as improving the shape of a nose, bringing outstanding ears closer to the head, or lifting the skin to erase wrinkles, and the term cosmetic surgery is often used to refer to such surgical procedures. Modern plastic surgeons often employ CAT scans to produce computer-generated images that are used to plan or simulate complex reconstructive surgeries.

laparoscopic surgery: see endoscope.

cosmetic surgery, plastic surgery for cosmetic purposes, such as the improvement of the appearance of the face by removing wrinkles or reshaping the nose.

Branch of medicine concerned with treatment by physical means rather than drugs. In addition to operations requiring access to the inside of the body (open surgery), it includes manipulation from outside the body (e.g., setting of a broken bone, skin grafts). Modern surgery began in the mid-19th century with use of anesthetics and antiseptics. Other important advances have included diagnostic imaging, blood typing, intubation to support breathing, intravenous administration of fluids and drugs, heart-lung machines (see artificial heart), endoscopy, and devices that monitor body functions. Specialized instruments used in surgery include scalpels to cut tissue, forceps to hold blood vessels closed or grasp and manipulate structures, clamps to immobilize or crush tissues, gauze sponges to absorb fluids and keep an area dry, retractors to hold incisions open, and curved needles to suture them closed. Pre- and postoperative care is crucial to the success of surgery. Seealso microsurgery, open-heart surgery, orthopedics, plastic surgery, transplant.

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Surgery to correct disfigurement, restore function, or improve appearance. It may involve reshaping or moving tissues to fill a depression, cover a wound, or improve appearance. Cosmetic surgery solely to improve appearance is not the main focus of plastic surgery. It is utilized after disfigurement by burns or tumour removal or for reconstructive work, and it may involve hiding incisions in skin folds or using buried sutures to hold wounds closed. Reconstructive plastic surgery corrects severe functional impairments, fixes physical abnormalities, and compensates for tissue lost to trauma or surgery. Microsurgery and computerized diagnostic imaging techniques have revolutionized the field.

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or orthopedic surgery

Medical specialty concerned with the skeleton and its associated structures. Orthopedists treat fractures, strained muscles, torn ligaments and tendons, and other injuries and deal with acquired and congenital skeletal deformities and the effects of degenerative diseases such as osteoarthritis. Originally dependent on heavy braces and splints, orthopedics now uses bone grafts, hip and other joint replacements, prostheses (see prosthesis), special footwear, and braces to enhance mobility. Orthopedics uses the techniques of physical medicine and rehabilitation and occupational therapy in addition to those of traditional medicine and surgery.

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Any surgical procedure opening the heart and exposing one or more of its chambers, most often to repair valve disease or correct congenital heart malformations (see congenital heart disease). Invention of the heart-lung machine (see artificial heart), which allows the heart to be stopped during surgery, made it possible. The first successful open-heart surgery was performed in the U.S. in 1953 by John H. Gibbon, Jr., to close an atrial septal defect.

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