A study published on bmj.com today concludes that using metal staples to close wounds after orthopedic (joint) surgery can lead to a greater risk of infection than using traditional nylon sutures.

Therefore, while further trials are carried out to confirm these findings, orthopedic surgeons are advised to reassess their use of staples to close wounds after hip or knee surgery.

Following orthopedic procedures like knee and hip surgery, wound complications are one of the main sources of illness. They can extend a patient’s stay in hospital or even lead to re-admission. In addition, there is a link between superficial wound infection and deep infection.

To close wounds, orthopedic surgeons use both metallic staples and nylon sutures. Staples are considered faster and easier to use than sutures. However, there is suggestion that staples are more likely to cause infection and may also be more expensive.

It is still unclear which method of skin closure is the best. In order to find out more, researchers at Norfolk and Norwich University Hospital analyzed the results of six trials. They compared the use of staples to sutures following orthopedic procedures in adults.

The trials involved 683 wounds from which 322 patients underwent suture closure and 351 staple closure. In general, the risk of developing a superficial wound infection was over three times greater after staple closure than suture closure.

For hip surgery only, the risk of developing a wound infection was four times greater after staple closure than suture closure.

There was no significant difference between sutures and staples in:

• the development of inflammation
• discharge
• dehiscence (re-opening of a previously closed wound)
• necrosis
• allergic reaction

The authors call attention to the fact that the quality of evidence was generally poor. They call for high quality, well designed trials to confirm their findings. However, based on the existing evidence, they suggest that patients and doctors should consider more cautiously the use of staples for wound closure after hip and knee surgery.

In an associated editorial, Bijayendra Singh, Consultant Orthopedic Surgeon, notes that these results correspond with evidence from other specialties. He remarks that the most consistent benefit of staples is more rapid skin closure. However, the time saved is rarely more than two to three minutes. The saving may also be reduced by the increased costs of removing the staples, compared with absorbable stitches. This might be reduced even further by the costs of treating the increased number of infections.

“Sutures versus staples for skin closure in orthopaedic surgery: meta-analysis”
Toby O Smith, research physiotherapist in orthopaedics, honorary lecturer Debbie Sexton, senior orthopaedic physiotherapist Charles Mann, consultant orthopaedic surgeon Simon Donell, consultant orthopaedic surgeon, honorary professor in musculoskeletal disorders
BMJ 2010; 340:c1199

“Staples for skin closure in surgery”
B I Singh, consultant orthopaedic surgeon, C Mcgarvey, specialist registrar, trauma and orthopaedics
BMJ 2010; 340:c403

Written by Stephanie Brunner (B.A.)