There are many types of suture patterns to close incisions and wounds. The medical practitioner should understand the basic fundamentals of suturing techniques in order to perform the best closure for healing.
Suture patterns can be categorized based on:
- Interrupted or continuous
- Appositional, everted (and inverted)
- Which tissue layer is to be closed
Interrupted Suture Patterns
Allows adjustment of tension throughout the suture line
Failure of one suture knot is often inconsequential
More time needed to tie individual knots
Poor suture economy
Increased amount of foreign material in the wound
Continuous Suture Patterns
Less foreign material in the wound
Potentially better airtight or watertight seal
Failure of knot leads to disruption of the suture line
Less precise control of wound approximation tension.
Apposition, eversion (and inversion)
Wound closure requires apposition of the sides of the tissue planes. Apposition (meaning, side-to-side) refers to bringing the tissue edges, or sides, of the wound next to each other for proper healing. If edges are not touching each other, dead space in the deep tissues, or gapping in the external layers, can lead to poor healing and possibly infection. (Conversely, closing of the wound too tightly can also lead to poor tissue healing due to strangulation and possible necrosis).
As the external skin wound heals, it will naturally contract. Therefore, everting the skin closure allows the final wound to heal flat after contracting, rather than puckering down (i.e., inverting) from the flat plane. (Inverted suture patterns had previously been used in closing hollow viscera, but studies have shown no added benefit to healing viscera, so the inverted suture pattern is now rarely used).
A simple interrupted suture pattern can be used at any layer of a wound (e.g., externally at the skin, deeper at the dermal and subcutaneous layer, or even with repair of blood vessels or viscera). When closing the dermal or subcutaneous layer with simple sutures, remember to pass your needle up from the inside of the layer first (instead of down from the outside as with skin closure) in order for your knot to end up being buried and not poking up at the epidermis (see “How to Suture: Intradermal and Subcuticular Sutures” video).
A simple continuous pattern can also be used externally or internally. Skin closure, deep fascial closure, and blood vessel or hollow viscous anastamosis can use a simple continuous pattern. Be sure that each pass of the needle is of the same depth throughout the continuous suture pattern.
A very cosmetic closure of the skin involves a continuous subcuticular suture pattern (see “How to Suture: Intradermal and Subcuticular Sutures” video) at the plane between the dermis and epidermis. The subcuticular closure allows for slight eversion of the epidermis and a watertight seal and is often used by plastic surgeons for final skin closure.
Final thoughts on suturing-
- Think wound apposition when performing wound closure
- Consider advantages and disadvantages when deciding on interrupted versus continuous suture patterns to close a wound
- Apposition or slight eversion are preferable to facilitate flat healing of the wound.
- Keep it simple and focus on what matters. Don't let yourself be overwhelmed. -Confucius