SURGICAL MESH WITH ADHESIVE
© SCIENTIFIC AMERICAN/LARRY GREENEMEIER

Every operation starts with a cut and ends when the incision is closed. And though the closing act that follows a complicated surgery may seem almost incidental, a surgeon's choice of needles, sutures or adhesives to do the job plays a big part in how well and how quickly the patient heals.

These days, there are more tools than ever at a surgeon's disposal. The choice of which one to use is as much art as science, often boiling down to a surgeon's personal preference, says Lee Nelson, a neurosurgeon with Boulder Neurosurgical Associates in Colorado. "Every surgeon probably uses 10 different types of sutures for different reasons," he adds. Flexibility, elasticity and strength of the materials are part of the calculation.

View our image gallery for a closer look at some of these tools of the trade.

The composition and thickness of a suture and needle depend on what the surgeon is closing. "Tissue near the spine is under a lot of tension, so you need a very strong suture," Nelson says, adding that he also uses a strong, thick suture when performing brain surgery. "But the fascia [or connective tissue] will heal itself and grow together, so you want a suture that's absorbable—generally lasting about three to four months." Closer to the skin, thinner needles and sutures are preferable because they leave fewer marks. (See a video explaining how surgeons chose the right needle for the job.)

Some sutures consist of a single strand of material that moves easily through tissue. Others are braids of multiple strands for increased strength and flexibility. "Monofilament sutures are less pliable than braided sutures but are easier to use in a continuous fashion because they don't cut the tissue as you pull them through," Nelson says. For this reason, he uses a monofilament suture when closing a patient's dura mater (the outermost of three layers of tissue surrounding the brain and spinal cord). "You want the [dura mater] to be watertight," Nelson adds. "The problem with the dura is that you create holes in it while you're suturing it, which could lead to a loss of spinal fluid. No one's been able to solve that problem."

Sutures are typically made from synthetic materials such as polymers. Natural materials, such as animal gut or silk, once dominated the market. But less than 10 percent of the sutures used in the U.S. today are made from gut, says Ed Dormier, vice president for new technology at Ethicon, a unit of Johnson & Johnson, in Somerville, N.J. (See a video of Dormier describing different types of sutures and their use.)

Surgeons also have the option of using staples made of plastic, stainless steel or titanium to tightly close incisions, either of internal organs or skin. Staples, the majority made by Johnson & Johnson's Ethicon Endo-Surgery, Inc., subsidiary in Cincinnati or Mansfield, Mass.–based Covidien, take less time to close a wound but are not as flexible as sutures, whose tension the surgeon controls. "I use staples to close cranial incisions behind the hairline," Nelson says, because they are quick and effective but tend to leave more visible scars. "I close all other visible incisions with suture."