With any suturing technique, knowledge of the relevant anatomy is critical. When placing a simple interrupted suture it is important to recall that the structures deep to the epidermis may be compromised by the passage of the needle and suture material. For example, the needle may pierce a vessel leading to increased bleeding.
Similarly, particularly if the knot is tied relatively tightly, structures deep to the defect may be constricted. This can lead to necrosis due to vascular compromise or even, theoretically, superficial nerve damage.
The potential to constrict deeper structures may be used to the surgeon’s advantage in the event that a small vessel deep to the incision line is oozing; rather than opening the wound, localizing the source of the bleed, and tying off the individual vessel, it may be possible to simply place an interrupted suture incorporating the culprit vessel within its arc, tie it tightly, and thus indirectly ligate the vessel. This should only be used in the event that the offending vessel is relatively small, since otherwise there is a significant risk that this indirect ligation will not be sufficiently resilient. Moreover, tying the suture too tightly may increase the risk of developing track marks or superficial necrosis.
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 in the event that sutures will not be able to be removed in a timely fashion. Some studies have also demonstrated an increased rate of dehiscence when utilizing interrupted sutures alone without underlying dermal tension-relieving sutures, highlighting that this technique should be used either for wounds under minimal tension or in concert with deeper tension-relieving sutures.