When the surgeon is aiming to make his scar as inconspicuous as possible suturing of the wound becomes an extremely precise procedure, prefer-ably using the instrumental method of suture tying. The necessarily small needles and fine suture materials make tying by hand clumsy and difficult.
Instrumental tying allows the tension of the suture to be regulated, and knot placement to be carried out with much greater finesse, precision and expedition. The more a wound is traumatised in the process of suturing the less good is the cosmetic result likely to be and the implements used for holding wound margins steady for suturing should be as atraumatic as possible.
The skin hook may cause minimal trauma to the wound margins, but it is difficult to use with elegance and speed, and dissecting forceps are more rou-tinely used. Individual preference will decide whether the toothed or non-toothed variety is used. The decision is immaterial as long as both are used with due regard to the trauma they are causing.
The aim is to produce an accurately and a traum- atically coapted wound, and the technique of handling and suturing is merely a means to this end. First-time accurate placing of the suture is a habit to acquire. The second attempt is all too often worse than the first, and only results in a moth-eaten wound edge and poor scar.
The needles used are curved and move most readily in a circle. The wrist must therefore be rotated as part of the movement involved so that insertion of the needle and its pull-through are in the line of its curve. Slight oedema of the wound tends to develop for a short time after a wound is sutured and allowance should be made for it in tying the suture.
The correct suture tension just avoids blanching the skin held by the suture. Tied too tightly, the suture cuts in more rapidly and is more likely to leave a suture mark. Sutures may be interrupted or continuous.
When the cosmetic result is all-important inter-rupted sutures are used, but continuous sutures are often adequate in other circumstances. Interrupted sutures The standard suture is the simple loop suture .
It consists of a simple loop knotted at one or other side of the wound, and aims to bring the skin edges together accurately with no overlap-ping of one margin. A general tendency towards slight eversion of the suture line helps to ensure complete dermal apposition. It also makes sure that inversion of the wound edges, which generally results in a poorer scar, is avoided.
The suture should include at least the entire thickness of the dermis, and the needle should take an equal bite of each side. The taking of an equal bite can be viewed as the ‘coarse adjust-ment’ of getting the wound edges level. One or other edge may remain a little lower than its fellow, and it can be raised to match the levels of the two edges by manipulating the knot in tying to that side of the wound.
Each suture has an optimal side for its knot, and its manipulation is the fine adjustment’. The desired degree of wound eversion is achieved in several ways. The taking of a slightly greater bite by the needle of its deeper part, dermis or fat, has the effect of approximating the entire face of the wound edge and creates a degree of eversion.
The wound edges are also sometimes undermined for 2-4 mm and held everted as the needle is inserted, allowing its path to take the desirable greater deep bite. As already indicated a skin hook can be used to hold the wound edge everted , though dissecting forceps are more usual. The side of the thumb can also be used effectively to evert the skin during the insertion of the needle. As a rule it is technically easier to suture from the more mobile side of the wound to the more fixed side. Where the skin is thin and poorly supported, or mobile on its deep surface, e.g. around the eyelids, it is particularly difficult to avoid inver-sion, and a solution may be to use the vertical mattress suture .
This suture has no greater tendency to leave suture marks than any other if it is not tied too tightly and is removed early, and if the superficial bite is minimal the tendency to invert is corrected. When there is no tension of the wound, inter-rupted sutures alone are adequate. When there is an element of tension, the use of buried absorbable sutures , or a continuous intradermal suture , is described with the aim of allowing early removal of skin sutures without wound disruption or stretching. Surgeons vary in the extent to which they use buried absorbable sutures to close the skin in layers, as opposed to relying on a single layer of skin sutures. The similarity in the results obtained by surgeons using both techniques would indicate that the routine use of layered closure is not strictly necessary.
The method probably has its real value when it is used to eliminate dead space, and prevent haematoma. The use of a continuous intradermal suture to diffuse wound tension has the merit that the suture can be left in for 10-12 days without leav-ing suture marks. Although it may be used by itself, it will be found that really accurate skin edge apposition is only possible if additional interrupted skin sutures are used.
Its role then is to reduce tension on the interrupted sutures, and the smooth surface of monofilament materials used in this capacity makes for easier removal.
The most useful continuous sutures are the ‘blanket’ stitch and the continuous ‘over-and-over’ . The blanket stitch has the advantage of not ‘bunching up’ the wound and a double turn at each stitch converts it into a locked suture. The ‘over-and-over’ suture unfortunately does tend to bunch the wound.
Such sutures cannot be placed as accurately as the interrupted suture, but where an impeccable scar is not essential they certainly save time. It is sometimes stated that the continuous suture tends to strangulate the wound edge, but this is the result of unduly tight insertion rather than any inherent defect of the method.