Chapter 4.15: The Running Percutaneous Buried Vertical Mattress Suture

This running technique is designed to allow for moderate tension relief while concomitantly permitting easy suture placement in relatively tight spaces. It is best suited to areas with thicker dermis, though it may also be utilized in any body area when deep sutures are placed and where insertion of the full needle is challenging.

Some authors have advocated this technique as a replacement for standard running buried suture approaches, while others prefer to treat it as a niche approach exclusively for areas where other running fully buried approaches are more challenging to execute.

Suture choice is dependent in large part on location. Though suture material travels percutaneously, exiting the epidermis and then reentering, the smallest gauge suture material appropriate for the anatomic location should be utilized. Often absorbable suture material is used to allow for an entirely buried suture line. If reentry is to be attempted through the same hole as suture exit, monofilament suture material may be preferred over the braided alternatives. On the back and shoulders, 2-0 or 3-0 suture material is effective, though theoretically the risk of suture spitting or suture abscess formation is greater with the thicker 2-0 suture material, particularly where the material has exited the epidermis entirely. On the extremities, a 3-0 or 4-0 absorbable suture material may be used, and on the face and areas under minimal tension a 5-0 absorbable suture is adequate.

In addition to utilizing absorbable suture material, nonabsorbable suture material may also be utilized with this technique. In that event, the knots at the beginning and end of the suture line are tied externally, permitting easy suture removal. In such cases, a monofilament would be preferable to permit easy pull through at suture removal, reinsertion of the needle through the same hole, and a more pronounced pulley effect.

1. If possible, the wound edge is reflected back using surgical forceps or hooks. In areas under marked tension, or where full visualization is not possible, the needle may be blindly inserted from the undermined space.

2. The suture needle is inserted at a 90-degree angle into the underside of the dermis 4-mm distant from the incised wound edge.

3. The first bite is started by following the needle and traversing from the underside of the dermis in the undermined space and passing entirely through the dermis and exiting the skin.

4. The needle is then reloaded onto the needle driver with a backhanded technique, and inserted through the epidermis either directly through the same hole as the suture followed during exit, or just medial to it. A shallow bite is taken and the needle exits on the margin of the incised wound edge.

5. The needle is then reloaded, again in a backhanded fashion, and it is inserted into the contralateral incised wound edge at the same depth as it exited on the first side. The needle again follows a mirror-image superficial course through the dermis, exiting through the epidermis again approximately 4 mm from the wound edge. Alternatively, this step may be combined with the prior step and the needle can be inserted into the contralateral edge while it is still loaded from the initial pass exiting the incised wound edge.

6. The needle is then loaded in a standard fashion and inserted either through the same hole or just lateral to it, following a deeper course and exiting the undersurface of the dermis into the undermined space.

7. The suture material is then tied, securing the anchoring stitch, and the trailing end is trimmed.

8. Steps (1) through (6) are then repeated sequentially for the desired number of throws, moving proximally toward the surgeon after each set of two sutures.

9. The suture material is then tied utilizing an instrument tie (Figures 4-15A, 4-15B, 4-15C, 4-15D, 4-15E, 4-15F, 4-15G, 4-15H, 4-15I, 4-15J). The final anchoring knot is tied by leaving a loop on the penultimate throw, and tying the free end of suture material from the final throw to this loop. The ends of the suture are then trimmed.

This technique is best for areas where placement of a traditional running buried suture is challenging due to limited space, such as the scalp and lower leg, though it has been advocated as an approach with broader application.

This approach may also be used when it is difficult to visualize the undersurface of the dermis, since the needle throws may be placed in an almost blind fashion. The skin is grasped gently to make it taut and the needle is inserted through the undermined space, exiting on the outside of the skin. This may be executed by feel, an approach well suited to the scalp where minimal dermal elasticity precludes full exposure of the undersurface of the undermined dermis.

It is critical to focus on outstanding knot security, since the entire suture line is held in place by the knots at the beginning and end of the set of suture throws. Adding an additional tacking knot when utilizing this approach is an option as well, and may provide additional knot security. Alternatively, one could consider placing an additional knot throw or leaving a longer suture tail when utilizing this approach.

Like the running percutaneous set-back dermal suture, this technique may be conceptualized as a largely buried alternative to the simple running closure, since both approaches do not require wide undermining or an easily reflected wound edge and both approaches may be utilized in areas under modest tension.

A theoretical benefit of the running approach is that there is less suture material left in situ, since the bulk of retained absorbable suture material is in the knots; as there are knots only at the beginning and end of the row of sutures, this technique theoretically decreases the risk of suture spitting and suture abscess formation.

Since suture material exits the skin and then reenters, dimpling may occur. Patients should be warned that this is expected and will resolve with time. Reentering the skin through the same hole may help minimize the risk of dramatic dimpling, though it carries the attendant risk of damaging the suture material with the needle, potentially leading to suture breakage.

Setting back the first throw far from the incised wound edge may result in over-eversion; the chief drawback of over-eversion is that the dermis may overhang in the center of the incised wound edge, barring the epidermal edges from approximating appropriately, leading to a slightly wider final scar. This may be easily solved by carefully beveling the dermis to allow the epidermal edges to meet unimpeded.

Patients should be cautioned that they might develop a significant ridge in the immediate postoperative period. Depending on the suture material used and the density of the sutures, this ridge may last from weeks to months.

Since suture material traverses the epidermis, there is a theoretically greater risk of infection with this technique than with approaches that remain entirely buried on the undersurface of the dermis. Meticulous attention to sterile technique may help mitigate this theoretical risk, and anecdotally infection is seen no more frequently with this approach than with any other closure technique.