Negative pressure wound therapy reduces infections in lower extremity fractures

Prospective randomized trial looked at tibial plateau, pilon, calcaneal fracture wound care.

Issue: February 2008

This patient developed fracture blisters following a calcaneus fracture. The blisters were de-roofed and treated with negative-pressure wound therapy for 5 days, with remarkable improvement in the condition of the skin. Images: Stannard JP

Traumatologists who conducted a multicenter trial into closing high-risk lower extremity fractures with standard dressings vs. negative-pressure wound therapy found the vacuum-assisted closure technique better mitigated the risk of infection.

“Our data suggest there is a significant difference between incidence of infection with the application of negative-pressure wound therapy (NPWT) in a prophylactic manner. They also suggest that there may be a significant decrease in wound dehiscence following high-risk fractures,” James P. Stannard, MD, said.

Stannard and colleagues at his center, the University of Alabama, Birmingham, and others in Nashville, Tenn., Atlanta and Indianapolis conducted the prospective trial, randomizing 249 patients (263 fractures) into two groups. All patients had tibial plateau, pilon or calcaneal fractures that were fixed standardly. Wounds were closed normally, but the control group received a standard dressing and the other group had a vacuum-assisted closure NPWT system placed over their wounds (VAC, Kinetic Concepts Inc.).

The strategy of using NPWT prophylactically is new, yet effective, Stannard said, when he presented the results at the Orthopaedic Trauma Association 23rd Annual Meeting.

Acute vs. delayed infection

Tibial plateau or calcaneus fractures not fixed within 16 days and pilon fractures not fixed within 21 days of injury were excluded from the study. Patients with each type of fracture were equally distributed between the two groups and the groups were similar in terms of soft tissue and injury severity scores.

Investigators used the NPWT system set at 125-mm continuous mercury for about 2.5 days (59 hours) in the treatment group.

Overall six acute and 32 delayed infections occurred in the study cohort with five acute infections in the control (4%) vs. one in the NPWT (0.7%) group. Nineteen delayed infections occurred in the control group (16%) vs. 13 in the NPWT group (9%).

“When you analyze that statistically, acute infections have a borderline or near significant difference in NPWT with a P value of .098,” Stannard said.

$An open tibia fracture$
An open tibia fracture following high-energy trauma.

Wound dehiscence and infection with exposed hardware following ORIF of a calcaneus fracture.

Chronic wound dehiscence with exposed hardware following ORIF of a calcaneus fracture.

Lower dehiscence rate

Concerning total infections, “there was a significant difference with P value .35. Again NPWT helped to prevent and was associated with fewer wound infections,” Stannard said.

There were 32 overall cases of wound dehiscence; 17% occurred in the control and 9% in the NPWT group. Most cases were in patients with calcaneal fractures. Time to discharge was not significantly different between the groups.

More research is needed into NPWT, but “this does provide some level 1 data,” he said.

Negative-pressure wound therapy applied to fracture blisters of a patient following trauma.

For more information:

James P. Stannard, MD, can be reached at 510 20th St. South, 950-B Faculty Office Tower, Birmingham, AL 3524-3409; 205-934-9545; e-mail: james.stannard@ortho.uab.edu. All centers involved in the study received institutional support from Kinetic Concepts Inc.

Reference:

Stannard JP, Volgas DA, McGwin G, et al. Negative-pressure wound therapy following high-risk lower extremity fractures. #12. Presented at the Orthopaedic Trauma Association 23rd Annual Meeting. Oct. 17-20, 2007. Boston.