Understanding Interrupted Sutures
Interrupted sutures are a common technique used for wound closure where each stitch is placed and tied individually. This contrasts with continuous or running sutures, which use a single strand of material to close a wound. The interrupted method is valued for its security, as the failure of one stitch will not compromise the entire closure. However, for many types of wounds, and especially in areas where speed and cosmetic results are a priority, this technique has notable drawbacks.
The Key Disadvantages of Interrupted Sutures
Increased Operative Time
One of the most significant drawbacks of interrupted sutures is the amount of time and surgical material required for their placement. Each individual stitch must be passed through the tissue, and a knot must be tied, cut, and secured. For long incisions, this process can be lengthy and tedious, increasing the overall time spent in the operating room. This time factor is particularly important in emergencies where rapid closure is necessary to minimize blood loss or reduce anesthesia time.
Higher Risk of Infection
Because each stitch is an independent unit, interrupted sutures introduce more foreign material (in the form of multiple knots) and create more entry and exit points in the skin than a continuous suture. These multiple knots and skin punctures can become potential sites for bacterial colonization. Over time, these areas can accumulate debris, increasing the risk of wound exposure and subsequent infection. While aseptic technique minimizes this risk, the sheer number of knots compared to a continuous closure represents a disadvantage.
Less Favorable Cosmetic Outcome
Interrupted sutures are associated with a higher risk of crosshatched marks, often called 'train track' scars, across the suture line. This occurs because each individual stitch applies pressure to the wound edges, and the external knots can cause localized tissue strangulation. To minimize this effect, sutures must be removed early, typically within 5 to 7 days, to prevent epithelialization into the suture tracks. However, early removal may be less ideal for wounds requiring longer support. For cosmetically sensitive areas like the face, many surgeons prefer alternative techniques to achieve a smoother, more aesthetically pleasing result.
Potential for Variable Tension
With interrupted sutures, the tension is isolated to each individual stitch. While this can be beneficial for specific wound configurations, it also means that the tension is not evenly distributed along the entire wound length. This can result in uneven wound approximation if not performed with meticulous precision, potentially causing tissue bunching or gaping. In contrast, a well-placed continuous suture distributes tension more uniformly across the wound. If a surgeon is inconsistent in their technique, the resulting wound closure can have areas of high tension next to areas with inadequate approximation.
Increased Risk of Wound Bleeding
Some evidence suggests that interrupted sutures may lead to more bleeding from the gaps between the individual stitches compared to the sealing effect of a continuous suture. This is more of a theoretical risk, but it is a consideration in cases where hemostasis is a concern.
Interrupted vs. Continuous Sutures: A Comparison
| Feature | Interrupted Sutures | Continuous Sutures |
|---|---|---|
| Time Efficiency | More time-consuming due to individual stitches and knots. | Faster to place, especially for long wounds. |
| Infection Risk | Higher risk due to multiple knots and skin punctures. | Lower risk due to fewer knots and skin entry points. |
| Cosmetic Outcome | Higher risk of prominent scars ('train tracks'). | Generally results in a smoother, more aesthetic scar line. |
| Wound Security | High; failure of one stitch does not cause complete dehiscence. | Lower; if the single strand breaks, the entire wound may open. |
| Tension Distribution | Isolated to each individual stitch, which can be uneven. | Distributed evenly along the entire wound length. |
| Suture Material | Typically requires more material than a continuous suture for the same length of wound. | Requires less material, making it more cost-effective. |
When are Interrupted Sutures a Poor Choice?
Based on their disadvantages, interrupted sutures are not ideal for all wound closures. Specific situations where a surgeon may opt for a different technique include:
- Long, straight incisions: Where speed is a factor, a continuous suture is often more efficient.
- Cosmetically sensitive areas: On the face or other visible areas, continuous subcuticular sutures or other specialized techniques are preferred to minimize scarring.
- Wounds under high tension: For closures that require significant deep support, interrupted sutures alone are often insufficient. Additional techniques like deep dermal sutures or specialized mattress sutures are necessary.
- Wounds with robust blood supply: While some evidence is theoretical, in areas where robust blood supply can compensate for potential microcirculation issues, the speed of a continuous suture can be advantageous.
- Minimizing material use: In cases where minimizing suture material is a consideration, a continuous suture is a more cost-effective choice.
Conclusion
While interrupted sutures remain a valuable and secure method for wound closure, they are not without their disadvantages. The increased time required for placement, higher potential for infection due to multiple knots, and risk of an unfavorable cosmetic outcome are all factors that surgeons must weigh against their known benefits. In modern surgical practice, the choice between interrupted and other techniques, such as continuous or subcuticular sutures, often depends on the specific wound's location, size, and the desired cosmetic result. For many applications, the efficiency and superior aesthetic potential of alternative methods can outweigh the individual security of each interrupted stitch.
For more information on surgical techniques, you can consult authoritative medical resources like Medscape.
