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How To Repair a Laceration With Simple Interrupted Sutures


Matthew J. Streitz

, MD, San Antonio Uniformed Services Health Education Consortium

Last full review/revision Mar 2021| Content last modified Mar 2021
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Uncomplicated epidermal closure is most often done using simple interrupted sutures. Each suture consists of a single, roughly circular (ie, simple) loop of suture material, individually tied. This technique permits individual tensioning of each suture, and if one suture should later fail, the others remain unaffected.

Simple cutaneous suture

Simple cutaneous suture


  • Wounds sufficiently deep that they would heal with excess scarring if not closed

  • Wounds having edges that can be satisfactorily approximated using these sutures

  • Wounds that are relatively recent and uncontaminated


Absolute contraindications

  • None

Relative contraindications

Sutures of any type may be contraindicated for wounds that are contaminated, relatively old, or that would be at higher risk of infection if closed by sutures, such as small bites to hands or feet, puncture wounds, or high-velocity missile wounds.

Wounds involving deep structures (eg, nerves, blood vessels, ducts, joints, tendons, bones) and those covering large areas or involving the face or hands may require specific repair techniques or referral to a surgical specialist.


  • Infection

  • Cutting or scarring of skin due to pressure on the skin from the sutures

  • Ischemia and necrosis due to excessively tight sutures


Wound hygiene and closure techniques need not be sterile procedures. Although instruments that touch the wound (eg, forceps, needles, suture) must be sterile, clean nonsterile gloves as well as clean but not sterile water may be used in immunocompetent patients. Some operators prefer the better fit and better barrier protection of sterile gloves.

Clean procedure, barrier protection

Additional Considerations

  • Wound tissue is vulnerable to further injury during any aspect of cleansing and closure. Never grasp the wound edges with a hemostat because doing so can crush the tissue; instead, use a tissue forceps or tissue hook when lifting and everting the wound edges.

  • Use only a needle driver (not a hemostat or forceps) for placing sutures because a driver holds a needle most securely without damaging it.

  • Excessive tension on the repaired laceration increases the degree of wound scarring.


  • Position the patient comfortably reclined or supine.

  • Adjust the stretcher height so that you will be comfortable sitting or standing at the bedside.

  • With lengthy lacerations, position yourself so that the laceration is roughly parallel to the front of your body.

  • The laceration should be well lit, preferably with an overhead procedure light.

Step-by-Step Description of Procedure

  • Cleanse, anesthetize, irrigate, and debride the wound as necessary.

  • Place a sterile fenestrated drape over the wound. Place additional drapes nearby as needed to provide a large enough sterile work area.

Handling the instruments

  • Hold the needle driver in your dominant hand, with your index finger extended along the side. This grip gives the most control. Some experts recommend not putting your fingers in the finger holes of the needle driver while placing sutures; doing so can make it harder to insert the needle perpendicular to the skin. However, you may place your fingers in the holes when releasing the needle from the driver and also when you tie knots using the instrument (instrument tie).

  • Hold the tissue forceps in your nondominant hand, as you would a pencil. Do not close the tips of the forceps tightly on the skin, because this can damage tissues. Use only toothed forceps or a tissue hook when handling tissue to help prevent crushing the tissue.

  • Hold suture scissors with your index finger extended toward the tip for better control.

Inserting the sutures

Simple cutaneous suture

Simple cutaneous suture

Suture spacing

Suture spacing

The instrument tie

  • Hold the tip of the needle driver above and between the entry and exit sites of the suture. Use your nondominant hand to manually hold the long end of the suture (the needle-end). Be mindful of where the needle is lying and be careful to not allow the needle to stick your hand.

  • To lay down the first throw of the knot, wrap the needle-end (long end) of the suture OVER the end of the needle driver twice. Wrapping twice forms the base of the surgeon’s knot, which prevents the first throw from loosening. Next, rotate the driver 90 degrees and with it grasp the free (short) end of the suture. Pull your hands in opposite directions to lay down the first throw securely but not tightly; tight sutures risk cutting into the skin and causing ischemia as wound edema develops over the next several hours.

  • On the second and subsequent throws of the knot, wrap the needle-end of the suture OVER the needle driver only once. Grasp the free end of the suture with the driver and pull in opposite directions to tighten the knot. These subsequent throws may be pulled tightly.

  • Note that the suture is always drawn OVER the needle driver, and that your hands move in alternating directions across the laceration with each throw. Adhering to this method assures that all knots are square knots.

  • Place a total of about 4 throws. After the final throw, cut the suture with a scissors, leaving tails about 1 cm long.


Warnings and Common Errors

  • During pre-procedure preparation of the wound, diligently inspect the wound to avoid the frequent error of failing to note associated injuries of nearby tissues, foreign bodies, or body cavity penetrations.

  • Avoid overly tight sutures and use cautery sparingly because both can cause tissue ischemia.

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