Chapter 5.9: The Running Horizontal Mattress Suture with Intermittent Simple Loops

Like the standard running horizontal mattress suture, this is a running everting technique used for closure and epidermal approximation. It is useful, especially on the face, to aid in everting the wound edges when the dermis has been closed using a deep suturing technique. This technique may also be used in patients with atrophic skin, as the broader anchoring bites may help limit tissue tear-through that may be seen with a simple interrupted suture.

With all techniques, it is best to use the thinnest suture possible in order to minimize the risk of track marks and foreign-body reactions. On the face and eyelids a 6-0 or 7-0 monofilament suture may be used, though fast-absorbing gut may be used on the eyelids and ears to obviate the need for suture removal. Since the goal of this technique is primarily to encourage wound-edge eversion, fine-gauge suture material may be used on the extremities as well.

1. The needle is inserted perpendicular to the epidermis, approximately one-half the radius of the needle distant to the wound edge. This will allow the needle to exit the wound on the contralateral side at an equal distance from the wound edge by simply following the curvature of the needle.

2. With a fluid motion of the wrist, the needle is rotated through the dermis, taking the bite wider at the deep margin than at the surface, and the needle tip exits the skin on the contralateral side.

3. The needle body is grasped with surgical forceps in the left hand, with care being taken to avoid grasping the needle tip, which can be easily dulled by repetitive friction against the surgical forceps. It is gently grasped and pulled upward with the surgical forceps as the body of the needle is released from the needle driver. Alternatively, the needle may be released from the needle driver and the needle driver itself may be used to grasp the needle from the contralateral side of the wound to complete its rotation through its arc, obviating the need for surgical forceps.

4. The suture material is then tied off gently, with care being taken to minimize tension across the epidermis and avoid overly constricting the wound edges. The trailing end of suture is then trimmed.

5. Starting proximal relative to the surgeon, the needle is then reinserted perpendicular to the epidermis, approximately one-half the radius of the needle distant to the wound edge.

6. With a fluid motion of the wrist, the needle is rotated through the dermis, taking the bite wider at the deep margin than at the surface, and the needle tip exits the skin on the contralateral side.

7. The needle body is grasped with surgical forceps in the left hand, and pulled upward with the surgical forceps as the body of the needle is released from the needle driver.

8. The needle is then reloaded in a backhand fashion and inserted at 90-degrees perpendicular to the epidermis proximal (relative to the surgeon) to its exit point on the same side of the incision line as the exit point.

9. The needle is rotated through its arc, exiting on the right side of the wound (relative to the surgeon) in a mirror image of step (6).

10. Steps (5) through (9) are then repeated.

11. Moving proximally, the needle is then reinserted perpendicular to the epidermis on the right side of the wound, approximately one-half the radius of the needle distant to the wound edge.

12. With a fluid motion of the wrist, the needle is rotated through the dermis, taking the bite wider at the deep margin than at the surface, and the needle tip exits the skin on the contralateral side.

13. Again moving proximally, the needle is reinserted perpendicular to the epidermis on the right side of the wound, approximately one-half the radius of the needle distant to the wound edge.

14. With a fluid motion of the wrist, the needle is rotated through the dermis, taking the bite wider at the deep margin than at the surface, and the needle tip exits the skin on the contralateral side.

15. The needle is then reloaded in a backhand fashion and inserted at 90 degrees perpendicular to the epidermis proximal (relative to the surgeon) to its exit point on the same side of the incision line as the exit point.

16. The needle is rotated through its arc, exiting on the right side of the wound (relative to the surgeon) in a mirror image of step (6).

17. Moving proximally relative to the surgeon, these steps are sequentially repeated, occasionally inserting simple interrupted throws between the running horizontal mattress throws, until the end of the wound is reached. At that point, a loop is left in the penultimate throw and the suture material is then tied off gently, with care being taken to minimize tension across the epidermis and avoid overly constricting the wound edges (Figures 5-9A, 5-9B, 5-9C, 5-9D, 5-9E, 5-9F, 5-9G, 5-9H, 5-9I).

The ratio of horizontal mattress to simple running throws can be greater than 1 to 1; many surgeons favor a ratio of 2:1, while the original published description of this approach advocates a ratio of 4:1. On relatively short repairs on the face, a simple running interrupted loop may be placed at the center of the wound.

This approach helps mitigate the problem of challenging suture removal that is associated with the running horizontal mattress approach. The simple running loops are easily accessible at the time of suture removal and may be cut, thus allowing the suture material to be pulled through. An additional benefit is that the intermittent simple running loops help with wound-edge apposition, as the horizontal mattress components tend to evert the edges but do not always bring the wound edges together as elegantly as would otherwise be desired.

This technique is frequently used on the face, as it aids with dramatic wound eversion. Generally, if the dermis was closed using the set-back dermal suture, no additional eversion is needed; however, when the buried dermal suture or even the buried vertical mattress suture, are used, occasionally the wound edges do not evert to the desired degree.

This approach also helps minimize cross-hatched railroad track marks, since most of the suture material does not cross over the incised wound edge. Similarly, this technique can sometimes yield a neater immediate postoperative appearance, as even if bite sizes are not uniform this is not apparent to the observer, as only the portions of suture material parallel to the incision line are visible.

As always, it is important to enter the epidermis at 90 degrees, allowing the needle to travel slightly laterally away from the wound edge before fully following the curvature of the needle when utilizing this technique. This will allow for maximal wound eversion and accurate wound-edge approximation.

As with the simple interrupted suture, care should be taken to avoid skimming the needle superficially beneath the epidermis. This results from failing to enter the skin at a perpendicular angle and failing to follow the curvature of the needle. This may result in wound inversion as the tension vector of the shallow bite pulls the wound edges outward and down.

Even with the placement of intermittent simple running loops, this technique does not uniformly permit the same degree of wound-edge apposition as can be accomplished with other running transepidermal sutures, since the everting effect of the suture technique may even be associated with a small degree of gaping at the center of the horizontal mattress suture, and suture material does not cross over the incised wound edge. In the event that deeper sutures were carefully placed, this may not be a significant drawback, since the wound edges may be well-aligned from the placement of these deeper sutures.

With any suturing technique, knowledge of the relevant anatomy is critical. When placing a running horizontal mattress suture with intermittent simple loops it is important to recall that the structures deep to the epidermis may be compromised by the passage of the needle and suture material.

As always, structures deep to the defect may be constricted. This can lead to necrosis due to vascular compromise or even, theoretically, superficial nerve damage. These concerns are more acute with the running horizontal mattress suture than with the simple running suture, since the wide arc of the suture material and its horizontal component incorporate more skin and underlying structures, thus increasing the risk of strangulation.

This technique may elicit an increased risk of track marks, necrosis, and other complications when compared with techniques that do not entail suture material traversing the scar line, such as buried or subcuticular approaches. Therefore, sutures should be removed as early as possible to minimize these complications, and consideration should be given to adopting other closure techniques or utilizing fast-absorbing gut suture material in the event that sutures will not be able to be removed in a timely fashion.