Stitches and staples are two methods by which a wound may be closed. Stitches use specialized needles and thread to "sew" a wound closed. Staples are thin pieces of metal that are placed with a stapling device through the edges of a wound to hold it closed.
Wounds to the skin, fat, muscle, blood vessels, and other structures in the body may occur accidentally (as in a cut) or purposefully (as in a surgical incision). A number of different methods exist to close a wound; the method selected depends on the type of injury, the type of tissue injured, the location and depth of the injury, and the patient's health. Stitches and staples are two commonly used wound closure methods.
Sutures, as stitches are often called, are the way that most wounds are closed. Suture materials have various characteristics that determine their use. The two main components of suture materials are the needle and thread.
MATERIALS. Suture thread is often characterized by how long it retains its strength in tissue. Absorbable stitches lose their strength in a matter of days or weeks and are eventually absorbed by the tissue. This characteristic is useful for the suturing of subcutaneous tissues. Nonabsorbable stitches retain their strength for months to years and may never be absorbed by the tissue. They are generally used for skin and removed once the wound has sufficiently healed. Suture thread is made of various natural or synthetic components and comes in different diameters for use in different types of tissues. Very fine suture threads are used to close cuts on the face, while threads with a larger diameter are required for subcutaneous tissues.
Suture needles may resemble a conventional sewing needle with an eye through which suture material is threaded, or they come with suture thread attached at one end; this connection is called a swage. Needles may be straight or curved; the most commonly used shape is the semicircle, which permits easier manipulation through tissues by the clinician. Needles vary in length from less than 0.1 in (2 mm) to 2.4 in (60 mm). The point of a needle may be cutting (for such tougher tissues as the skin), rounded (for such easily penetrable tissues as the subcutaneous layers), or blunt (for such easily damaged tissues as the liver).
TECHNIQUE. While various stitching techniques may be used depending on the location of the wound and type of tissue to be sutured, basic suturing technique remains the same. Several instruments are necessary for proper wound closure, including dissecting scissors (for cleaning the wound); suture scissors (for cutting suture thread); a needle holder (for manipulating the needle); and forceps (for manipulating tissue). Wounds resulting from an injury must be cleaned before closure; dead tissue and foreign bodies are removed and the area is cleansed with an antiseptic. Sutures may be interrupted (each stitch is separately placed, tied, and cut) or continuous (one continuous piece of thread composes all the stitches); they may be placed at different angles and depths.
Nonabsorbable stitches should be removed several days to weeks after their placement, depending on their location. For instance, sutures on the face should be removed in approximately 5 days; sutures on the legs and abdomen, in 7 to 10 days; and sutures on the back, in 10 to 14 days. Strips of adhesive tape may be placed over the wound to help support the tissue while it is healing.
A distinct advantage that staples have over sutures is their quick placement—stapling is approximately three to four times faster than suturing. Staples are also associated with a lower risk of infection and tissue reaction than sutures. It is, however, more difficult to correctly align the edges of a wound for stapling, and staples generally cost more than sutures. Common locations of wounds that may be stapled are the arms, legs, abdomen, back, or scalp; wounds on the hands, feet, neck, or face should not be stapled. Additionally, staples may be used to connect cut ends of larger blood vessels or segments of the bowel.
MATERIALS. Individual staples are composed of stainless steel and have a crossbar that lies parallel to the skin, two legs that enter each edge of the wound, and tips that hold the staple in place. Staples are placed with the aid of a stapling device that generally holds between 5 and 25 staples. Forceps are also necessary to help align the edges of the wound together and hold them in place until staples can be placed.
TECHNIQUE. The wound is first cleaned of dead tissue and foreign bodies and washed with an antiseptic. The edges of the wound are aligned and held together with forceps or the clinician's fingers. The stapling device is held against the wound at the point at which the staple is to be placed. By squeezing the trigger on the stapling device, the staple is automatically placed into the skin; the depth of placement is controlled by how hard the stapling device is held against the skin. The staples should be removed in approximately the same time as sutures; this is done with a specialized staple remover.
Lammers, Richard L., and Alexander T. Trott. "Methods of Wound Closure." In Clinical Procedures in Emergency Medicine. Philadelphia: W. B. Saunders Company, 1998.
Polk, Hiram C., William G. Cheadle, and Glen A. Franklin. "Principles of Operative Surgery." In Sabiston Textbook of Surgery. Philadelphia: W. B. Saunders Company, 2001.
Doud Galli, Suzanne K. and Minas Constantinides. "Wound Closure." eMedicine. January 29, 2002 [cited April 29, 2003]. http://www.emedicine.com/ent/topic35.htm .
Lai, Stephen Y. "Sutures and Needles." eMedicine. September 10, 2001 [cited April 29, 2003]. http://www.emedicine.com/ent/topic38.htm .
Terhune, Margaret. "Materials for Wound Closure." eMedicine. March 13, 2002 [cited April 29, 2003]. http://www.emedicine.com/derm/topic825.htm .
Stephanie Dionne Sherk