Bovis ISSN 2398-2993

Surgery: suture patterns - overview

Introduction

• Probably as many different suture patterns as there are suture materials. Patterns consist of two basic types:
  • Interrupted -  each stitch is cut and tied as a separate entity.
    • Advantages:
      • Allows precise adjustment of tension along the length of the wound.
      • Failure of a single knot may not cause wound to break down.
      • Suitable for all tissue types.
    • Disadvantages:
      • Time consuming to place.
      • More knots, therefore more suture material left in wound.
  • Continuous - knots are placed only at the beginning and end of a running line of continuous stitches.
    • Advantages:
      • Less time consuming than interrupted sutures patterns.
      • Less suture material left in the wound.
      • Relatively fluid and airtight.
    • Disadvantages:
      • Failure of securing or finishing knot likely to lead to unraveling of entire suture line.
• Suture patterns can also be classified as everting, inverting and apposing:
  • Everting tends to turn the tissue edges outward.
  • Inverting sutures tend to turn the tissue inward.
  • Apposing sutures bring the tissue edges into direct contact without eversion or inversion.
• Another differentiation in suture patterns is whether they are a simple or mattress (tension) suture:
  • Mattress patterns:
    • Close an incision under tension better than simple patterns.
    • May slow down healing by compressing tissue on each side of the incision, compromising local blood supply.
    • Designed to withstand more tension by spreading the tension over a wider area.
    • May be appositional, inverting, or everting depending on whether suture material is placed full or partial thickness within the skin edge.

Suture knots

• There are some guiding principles of knot formation that should be followed:
  • Knots should be as small as possible to minimize foreign body reactions.
  • After the first loop is tied in a knot traction should be maintained to avoid loosening.
  • Extra knots do not add strength to an accurately tied knot.
• Useful knots to learn:
  • Aberdeen knot: the Aberdeen knot has been shown to be stronger and more secure than a surgeon's knot for ending a suture line. The Aberdeen knot is also of a smaller volume than a standard surgeon's knot. An Aberdeen knot tied with 3 throws and 2 turns has been shown to provide the maximum level of security.
  • Sliding knot: useful for placing a ligature deep in a body cavity, it should always be covered with a square knot for security to prevent the knot loosening.

Skin Closure

Muscle and fascia closing

Hollow organ closure

Tension sutures

Tendon repair (anastomosis)

Special Suture and Ligature Patterns