乌鸦传媒

Closure of orthopedic surgery wounds with staples rather than sutures is associated with a significantly higher risk of superficial infection, a meta-analysis found.

After orthopedic procedures in general, the risk of superficial wound infection was more than three times higher with a staple closure (RR 3.83, 95% CI 1.38 to 10.68, P=0.01), according to Toby O. Smith, BSc, and colleagues from Norfolk and Norwich University Hospital in England.

And after hip surgery specifically, the risk was more than four times as great (RR 4.79, 95% CI 1.24 to 18.47, P=0.02), the researchers reported online in the BMJ.

"Superficial infection in hip and knee arthroplasty is a worrying clinical sign because of the risk of the infection spreading through the dermal layers to the implant," they observed.

Both nylon sutures and metal staples are used for skin closure in orthopedic surgery. Some surgeons favor staples, considering them to be easier and quicker to use, but others say they're more expensive and carry a greater risk of infection.

To address this uncertainty, Smith and colleagues conducted a meta-analysis that included six studies, three of which were randomized, and 683 patients.

Three of the studies involved hip surgery, two included hip and knee arthroplasty, and one assessed upper and lower limb trauma surgery.

A total of 332 patients had suture closure and 351 had staples.

Although the risk of superficial infection was greater with staples, there were no differences between the two methods in the incidence of wound discharge, dehiscence, inflammation, necrosis, or allergic reactions.

In the studies that looked at outcomes after knee surgery, there was no difference in the incidence of wound infection.

In one study, patients reported greater pain with staple removal than with removal of sutures, and another determined that staples were three times more expensive than subcuticular vicryl sutures.

In discussing the issue of cost, however, the authors noted that the expense of staples could be offset by shorter operating times and ease of removal.

"This might prove to be false economy, however, as the consequences of a deep infection for the patient are substantial through the increased costs associated with medical care and admission to hospital," they wrote.

Among the consequences of deep infections are the potential need for extensive debridement, revision surgery, and even amputation.

The authors pointed out that only one of the studies was of acceptable methodologic quality, and that the others were hampered by shortcomings such as underpowered cohorts, poor randomization, inadequate follow-up, and lack of blinding.

Other limitations included a lack of demographic data and information about potentially confounding medical variables, and the fact that the studies failed to differentiate between superficial and deep wound infections.

It also was unclear which method provided a superior cosmetic result, because the studies did not analyze the results according to skin type, age, or comorbidities.

Because of these methodologic limitations, the authors called for further well-designed, randomized trials, but said that with the evidence they presented, "patients and doctors should think more carefully about the use of staples for wound closure after hip and knee surgery."

They cautioned, however, that their findings are generalizable only to orthopedic hip and knee arthroplasty surgery.

An accompanying editorial concurred about the need for randomized studies, citing the fact that two of the studies included in the meta-analysis exclusively included patients with hip fracture who may be particularly vulnerable to infection.

Studies are also needed "to discern whether the risks are exclusive to hip surgery and to compare the risk of infection with staples in elective hip arthroplasty as opposed to hip fracture," wrote Bijayendra I. Singh, FRCS, and C. McGarvey, FRCS, of the Medway Foundation NHS Trust in Gillingham, England.

"We now have national databases of the outcome of hip and knee arthroplasty and hip fracture, but currently neither records the method of skin closure. These databases could provide the platform to enable comprehensive adequately powered studies," the editorialists concluded.