While a central strength of the running subcuticular suture is its entirely intradermal placement, this may also represent one of its greatest drawbacks. This technique results in leaving a significant quantity of foreign-body material in the dermis in a continuous fashion. While this may not represent a major problem in areas with a thick dermis such as the back, in other anatomical locations the large quantity of suture that is left in situ may result in concerns regarding infection, foreign-body reaction, and even the potential that the suture material itself could present a physical barrier that would impinge on the ability of the wound to heal appropriately—essentially an iatrogenic eschar phenomenon.
A similar concern relates to leaving a suture tunnel if nonabsorbable suture material is used and is then removed after a period of time. As one of the benefits of this approach is to permit the suture to remain in place for many weeks or months, it also means that removal of long-standing suture entails a theoretical risk that a potential space—albeit a thin and long one—is created on the removal of the suture material. Again, this theoretical risk may be mitigated by utilizing the thinnest possible suture material.
If nonabsorbable suture material is used, care should be taken to account for the eventual necessity of suture removal. Since the nonabsorbable monofilament will be removed by applying a continuous gentle pull on the free edge of the suture, it is imperative that the length of the continuous suture be kept to a reasonable maximum, to avoid the risk of suture snapping mid pull. In cases where a longer wound is closed using nonabsorbable suture material, a single simple interrupted suture may be placed as part of the course of the suture material every 4 cm or so, providing a site where the suture material may be snipped and pulled through at the time of suture removal.
In the event that slow-absorbing absorbable suture is used, consideration should be given to utilizing undyed suture material, since depending on the depth of suture placement and the degree of epidermal atrophy the suture material may sometimes remain visible.
Depending on the placement of the deep sutures, it is possible for this technique to lead to some mild inversion of the epidermal edges as they are pulled inward by the suture material. This is particularly the case when the suture is finished with a fixed knot holding the ends of the suture material in a fixed position.