Scrapes and cuts are inevitable, and most are not a big deal — minor injuries often heal without treatment. However, some cuts and gashes require stitches to ensure proper healing and prevent infection. Stitches or surgical sutures hold body tissues together following an injury or surgery. Several factors determine whether or not a wound needs stitches, including the size and depth. Some cuts bleed significantly, making it difficult to determine if stitches are necessary.

Stitches

There are two main goals of stitches: to help close wounds fully, to promote healing, and to prevent infection. In some cases, physicians may use stitches to prevent scarring in cosmetically significant areas. Different needle size, material, and sewing techniques suit different wounds. Though most stitches use a needle and some form of thread, minor injuries may only require adhesive liquid stitches — essentially gluing the wound closed. Some wounds or procedures require both types.

Location

Certain areas of the body are more likely to need stitches. Joints move so often that the wound may not heal without them. Additionally, wounds that damage ligaments or tendons require immediate medical attention. Lacerations on the genitals or highly visible areas such as the face also require medical evaluation and may need stitches. Cuts on or near the eyes may impair vision without treatment. Deep wounds on the hands or fingers may also inhibit proper function.

Size

One of the most observable indicators that a wound needs stitches is size; specifically, the length and depth of the injury. Cuts deeper or longer than half an inch may need stitches. If an injury is deep enough to expose muscle, bone, or fatty tissue, it requires stitches, as do wounds that are notably wide or gaping, which may not heal at all, otherwise. The size of an injury also determines what type of sutures a doctor will use.

Causes that Require Stitches

Puncture wounds that result from a human or animal bite are particularly prone to infection. Not only will the injury need stitches, but they may also require antibiotics or a tetanus booster. Even minor gunshot wounds, such as grazes, may be of a depth or width that require stitches to close, as may lacerations from objects with jagged edges, such as saws or knives.

Amount of Blood

When an injury is bleeding, placing direct pressure can help slow blood loss. If bleeding does not stop after several minutes of direct pressure, the wound likely needs stitches. Blood that spurts may indicate a severed artery and the need for emergency care and sutures. Excessive bleeding makes it difficult to properly examine a wound, so it is best to seek medical attention.

Types of Wounds

Stitches are usually mandatory for treating open wounds. A physician considers a wound to be “open” if there is a break in the skin. Open wounds can be further subcategorized:

• Lacerations are simple cuts or breaks in the skin.
• Incisions are surgical wounds with smooth edges.
• Punctures result from an object entering the body and then exiting. Large punctures may look similar to lacerations.
• Avulsions occur when flaps of skin are open on three sides or completely torn away.
• Abrasions are scratches that are similar to avulsions, but with less depth.

Signs that Stitches Aren’t Necessary

It is sometimes easier to identify wounds that don’t need stitches. Most puncture wounds are small, but unseen internal damage may require medical attention. Wounds with smooth edges that do not open wider with normal movement will likely heal properly without stitches. Shallow wounds less than .25 inches deep and shorter than .75 inches in length do not typically need stitches.

Stitch Materials

Suture materials are either absorbable or non-absorbable. The body can naturally digest absorbable stitches, so they do not require a doctor for removal. Polydioxanone is a general-use material that can seal soft tissue wounds. Polyglactin is ideal for stitching hand or face injuries. Non-absorbable stitches are more common and are what people typically imagine when they think of stitches. Popular non-absorbable materials are nylon, silk, polyester, and polypropylene. These materials can close many types of wounds in most areas of the body.

Technique

Doctors will use different stitching techniques depending on the area and cause of the wound. Interrupted sutures use several strands of material to close an injury securely. Continuous sutures are easy to place and use a single strand. Buried sutures place the knot of the stitches inside the body. Purse-string sutures are continuous and tighten the skin like a drawstring on a bag. Subcutaneous sutures lie in the dermis of the skin, parallel to the wound.

Removing Stitches

If a doctor uses a non-absorbable material for the stitches, they will remove them at a later date. Face stitches may require removal after only three to five days while hand stitches may need to stay in place for up to three weeks. Doctors will sterilize the area before removal and may numb more sensitive locations. For the removal itself, they will cut one end of the thread and gently pull out the stitch.