Compared with standard dressings, negative pressure wound therapy (NPWT) does not improve 12-month outcomes in patients with open leg fractures, according to a new study published in JAMA.

Since they break the skin, open fractures have a higher risk of healing-related complications. Infection rates can be as high as 27 percent in severe open leg fractures, for example.

NPWT is a new type of postoperative dressing that creates a vacuum, removing the blood and fluid accumulating inside a wound. The vacuum of NPWT may promote the formation of granulation tissue, but the dressings and machines cost considerably more than standard wound dressings.

The researchers enrolled 460 patients from the UK Major Trauma Network into the multicenter randomized clinical trial. Participants were aged 16 or older with a severe open fracture of the lower limb from July 2012 through December 2015.

They had excluded participants who came to the emergency department more than 72 hours after injury, those who had a contraindication to anesthesia, and those who were unable to complete questionnaires.

The team of researchers assigned the participants to two groups. The 226 participants in the NPWT group received treatment that involved placement of gauze or an open-cell solid foam over the surface of the wound. A suction pump creates a partial vacuum over the dressing.

The 234 participants in the other group received standard dressings that did not involve the application of negative pressure.

The researchers assessed self-rated disability, deep infection rate and quality of life after 12 months. The Disability Rating Index (DRI) score at 12 months was the primary outcome measure.

This patient-reported outcome measure provides an assessment of a respondent’s disability. Participants rate their limitations on a scale of 0 (no limitations) to 100 (completely disabled). The researchers set the minimal clinically important difference at 8 points.

Secondary outcomes of the study were complications that included deep infection and quality of life at 30 days. The researchers used the EuroQol 5-dimension 3-level questionnaire (EQ-5D-3L) and the Short Form-12 (SF-12) to assess the participant’s quality of life.

Scores for quality of life ranged from 1 for the best possible to -0.59 for the worst possible. They set the minimal clinically important difference at 0.08.

The researchers collected information at 3, 6, 9, and 12 months. The researchers collected final outcome data through November 2016.

The scientists found no statistically significant difference between the self-rated disabilities between the patients who receive NPWT or standard wound dressing at 12 months. Specifically, those in the negative pressure wound therapy ground had an average self-rated disability score of 45.5 points out of a possible 100 points, while those in the standard wound dressing had an average self-rated disability of 42.4 at 12 months.

There also were no significant differences in secondary outcomes. Specifically, there were no significant differences in surgical site infections or other complications. Complete bone union rates were similar between the two groups as well.

The authors concluded their study by saying, "Among patients with severe open fracture of the lower limb, use of NPWT compared with standard wound dressing did not improve self-rated disability at 12 months. The findings do not support this treatment for severe open fractures."

The results of this study could help save money without compromising outcomes.