Whenever a suture is required to close a wound, needles to arm the suture material are necessary. The number of sizes and the variety of different shapes of needles run into many thousand. The range supplied by manufactures is usually classified into types for specific surgery, as for example, arterial, general purpose, intestinal, obstetric, ophthalmic, plastic, retention. Shapes are designated as: straight, curved, ½ circle,5/8 circle, etc. and the section as round bodied, triangular cutting edge, riangular reverse cutting, cutting point, trocar point. In addition the length of the needle from point to hilt is specified in millimeters and the hilts are designed to take the various diameters of suture material employed. Needles are chosen by the surgeon to suit his operating technique and it is largely because of the surgeon‟s interest in improving suture efficiency that the development of surgical needles has taken place. In very many cases the surgeon himself has caused needles to be made to his own design and a large number of commonly used needles are referred to by the name of the inventing surgeon.
Surgical needles are of two types; those which have an eye through which have an eye through which the suture is threaded, and eyeless needles where the suture is inserted into the hollow hilt and held in position by swaging the metal around it. The late Sir Henery Souttar obtained the first patent on an eyeless needle in 1921, but in the U.K. their use has only increased appreciably in the past few years. In the U.S.A. 70 percent of the suture needles are of the eyeless type.
The needles themselves are made either of stainless steel or of carbon steel, the latter usually being plated to resist corrosion. At one time the carbon steel needle had a better resistance to bending than its counterpart in stainless steel, but recent technological advances have the added advantage that they will not corroded and do not present the surgeon with the dreaded emergency of having to locate and extract the broken point of a needle embedded somewhere in the tissue of an unfortunate patient.