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Suture Needles
Conventional 1/2 and 3/8 suture needles are commonly used in MIS. Specialized half‐curved (“ski”) needles can be advantageous when operative space is limited. The J needle may be beneficial when closing port incisions. Straight needles can be used in special circumstances, but limited access precludes their general usage (ssss1).
It is helpful to use needles that are flattened along their bodies to allow stable grasping with an endoscopic needle holder. Taper or tapercut points are best. Reverse cutting needles may be used, but one must be conscious of the cutting edge on the convex surface. Inadvertent cutting of vascular structures is possible because of poor visualization of the back side of the reverse cutting needle. Usage of cutting needles should be avoided because the sharp concave edge cuts through tissue during needle passage. This can lead to suture “pull‐through” as well as increased hemorrhage.
Suture needles used in MIS should be strong enough to resist the increased forces placed on them during intracorporeal suturing. Suture needles are made of stainless steel alloys containing chromium and nickel. Chromium confers corrosion resistance, and nickel imparts strength to the needle. With the optimal component ratios, suture needles demonstrate the ability to deform without fracture, a property known as ductility [6]. Major suture manufacturers commonly produce standard and premium grade suture needles as part of their suture line. There is a premium to be paid for higher quality suture needles, which can be custom manufactured in combination with any suture material. Proprietary coatings are applied to suture needles to facilitate their tissue passage.