Understanding the Horizontal Mattress Suture
The horizontal mattress suture is a powerful, everting stitch used primarily for skin closure, especially in areas where wound edges are under significant tension. Its design allows it to distribute tension widely and effectively evert the edges, promoting a better cosmetic outcome and preventing inversion, which can lead to a less favorable scar.
The Technique
The placement of a horizontal mattress suture is distinct and involves a four-point entry/exit on the skin surface. The process is as follows:
- First Pass: The needle enters the skin on one side of the wound, travels horizontally through the deep dermis, and exits on the opposite side. The needle enters and exits far from the wound edge (e.g., 5-10mm).
- Second Pass: The needle is then reversed in the needle holder. It re-enters the skin on the same side it just exited, but a short distance away (e.g., 5-10mm) and parallel to the wound edge.
- Final Pass: The needle travels back across the wound, exiting at a point parallel to the initial entry, completing the mattress shape.
- Tying the Knot: The suture is then tied, with the knot lying to one side of the wound. When tied, the parallel external loops create tension, forcing the wound edges to evert.
Key Uses for Horizontal Mattress Sutures
- High-Tension Wounds: Closing wounds over joints or other areas prone to pulling apart.
- Fragile Skin: Effective for delicate or thin skin, such as in the hands, feet, or eyelids.
- Anchoring Sutures: Used to secure skin flaps or as an initial suture to pull wide wound edges together.
- Everting Edges: Ideal when wound edges tend to roll inward, ensuring proper apposition for healing.
Understanding the Figure 8 Suture
Also known as the cruciate mattress suture, the figure 8 suture is a robust and rapid technique, often used for hemostasis (controlling bleeding) and closing deep tissue layers, such as fascia. It is a variant of the horizontal mattress but is distinguished by the 'infinity sign' or 'figure 8' pattern it creates beneath the wound surface when tied.
The Technique
The figure 8 suture is often faster to place than a traditional horizontal mattress as it does not require reversing the needle. The procedure is as follows:
- First Simple Pass: A standard simple interrupted suture is placed, entering on one side and exiting on the other, deep within the tissue.
- Second Simple Pass: The surgeon moves a short distance along the wound and performs a second simple suture pass, parallel to the first, without tying. This creates the 'figure 8' shape under the surface.
- Tying the Knot: When the two ends are tied, the resulting 'X' or '8' shape provides strong tissue approximation and excellent hemostasis by compressing the bleeding vessels between the suture passes.
Key Uses for Figure 8 Sutures
- Deep Tissues: Commonly used for closing fascia in abdominal surgery or uterus after a C-section.
- Hemostasis: Highly effective for controlling bleeding in vascular tissues like the scalp or muscle.
- Large, Gaping Wounds: Provides significant strength for closing wounds where there is a large gap between edges, especially in deep layers.
- Minimized Tension: Unlike the horizontal mattress, the figure 8 minimizes longitudinal tension on the skin, reducing the risk of tissue strangulation.
Comparison of Figure 8 vs. Horizontal Mattress Sutures
| Feature | Horizontal Mattress Suture | Figure 8 Suture |
|---|---|---|
| Primary Function | Excellent edge eversion and tension distribution across the skin. | Strong deep tissue approximation and hemostasis. |
| Tension Management | Spreads tension across the skin surface, making it suitable for high-tension skin closures. | Minimizes longitudinal tension on the skin, ideal for deep layers. |
| Best For | Closing surface wounds under stress, securing skin flaps, or everting wound edges. | Closing deep layers, fascia, or vascular tissue where hemostasis is needed. |
| Technique | Involves two parallel passes, one further from the edge and one closer, with the needle reversed. | Two simple, parallel passes performed in succession without reversing the needle. |
| Speed | Can be more time-consuming due to the need for careful needle reversal and placement. | Generally faster to place than a horizontal mattress stitch. |
| Cosmetic Outcome | Promotes excellent skin edge eversion, which can lead to a less prominent scar if removed early. | Less desirable for surface skin closure as it can cause 'railroad track' scarring if used superficially. |
| Tissue Strangulation | Can cause tissue strangulation if tied too tightly, though this can be mitigated by placing bolsters under the loops. | Preferred over horizontal mattress for deep closures because it lessens strangulation risk on the surface. |
Choosing the Right Suture
The choice between a figure 8 and a horizontal mattress suture depends heavily on the specific clinical scenario. Surgeons evaluate several factors before selecting the appropriate technique:
- Anatomical Location: The type of tissue and its location are critical. A horizontal mattress is often favored for skin closure on flat surfaces or areas where good eversion is needed for cosmetic reasons. The figure 8 is reserved for deeper, more robust tissue or areas where bleeding needs to be controlled.
- Wound Tension: For a wound with significant superficial tension pulling the edges apart, the horizontal mattress is superior for broad tension distribution. However, in deep layers, the figure 8 provides necessary strength without compromising blood flow to the superficial tissue.
- Cosmetic Concerns: When appearance is a primary concern, the horizontal mattress must be used cautiously and removed early to minimize the characteristic 'railroad track' scarring. For deep closures where the final scar is less visible, the figure 8 is a powerful and faster alternative.
- Hemostasis Requirement: If there is significant bleeding from deeper vessels, the figure 8 provides immediate and robust hemostatic control by compressing tissue effectively.
- Tissue Type: The horizontal mattress is suitable for fragile skin, while the figure 8's strength is better suited for dense tissue like fascia.
Conclusion: Suture Selection is a Clinical Art
Ultimately, deciding between a figure 8 and a horizontal mattress suture is a clinical judgment call that balances the need for wound approximation, hemostasis, and cosmetic results. While related in their function of providing strong closure, their distinct applications make them invaluable but not interchangeable tools in a surgeon's armamentarium. The horizontal mattress dominates superficial, high-tension closures, while the figure 8 is the tool of choice for fast, strong closure in deep, vascular tissue. A thorough understanding of each technique ensures the best possible outcome for the patient.
For more detailed information on various wound closure techniques and other mattress sutures, consult authoritative medical resources like the American Academy of Family Physicians, which offers a robust guide on the topic.
