'The ideal suture would consist of material which permits its use in any operation, the only variable being the size as determined by the tensile strength. It should handle comfortably and naturally to the surgeon. The tissue reaction stimulated should be minimal and should not create a situation favourable to bacterial growth. The breaking strength should be high in small calibre. A knot should hold securely without fraying or cutting. The material must be sterile. It should not shrink in tissues. It should be non-electrolytic, non-capillary, non-allergenic and non-carcinogenic. Finally, after most operations the suture material should be absorbed with minimal tissue reaction after it has served its purpose.' 1
No single type of suture material has all these properties and therefore, no one suture material is suitable for all purposes. The requirement for wound support varies in different tissues from a few days for muscle, subcutaneous tissue and skin to weeks or months for fascia and tendon, to long-term stability for vascular prosthesis. However, the surgeon must be assured that the selected suture has the following properties:
Suture materials are either absorbable or non-absorbable. Absorbable sutures offer temporary wound support over a period of time and thereafter are gradually absorbed either through a process of enzymatic reaction (catgut) or hydrolysis (synthetic materials). It is important to recognise that losing tensile strength and losing mass absorption are two separate events. A suture may support the wound for only a very short time and yet be present as a foreign body for a long period after. The ideal suture would be one which disappeared immediately after its work was complete, but such a suture does not yet exist.
Non-absorbable sutures do not absorb, but some, especially those of biological origin, lose strength without any change in the mass of the suture material. Others gradually fragment over time. Yet other non-absorbables, especially those of synthetic origin, never lose tensile strength or change in mass following implantation.
Sutures can be subdivided into monofilament or multifilament. A monofilament suture is made of a single strand. It resists harbouring micro-organisms and ties down smoothly. A multifilament suture consists of several filaments twisted or braided together. This gives good handling and tying qualities.
A further classification is based on the origin of the raw material; it can either be from a biological source of from man-made fibres. Sutures have been produced from a biological or natural source for many thousands of years. They tend to create greater tissue reaction than man-made sutures; the result can be localised irritation or even rejection. Another disadvantage is that factors present in the individual patient, such as infection and general health, can affect the rate at which enzymes attack and break down absorbable natural sutures. Man-made or synthetic sutures, on the other hand, are very predictable and elicit minimal tissue reaction.
View the 'factors affecting wound healing' video clip
1 Postlethwait RW. Wound Healing in Surgery. Somerville, NJ: Ethicon Inc; 1971. pp8-9.
