The Effectiveness of Negative Pressure Wound Therapy Versus Conventional Dressing in the Treatment of Open Fractures: A Systematic Review and Meta-Analysis 

SLR - July 2020 - Fernando Ramirez

Reference: Marc C. Grant-Freemantle, MCh, Éanna J. Ryan, MD, Sean O. Flynn, MCh, Darren P. Moloney, MCh, Michael A. Kelly, MCh, Eamonn I. Coveney, MCh, Brendan J. O’Daly, FRCS (Tr & Orth), and John F. Quinlan, FRCS (Tr & Orth) The Effectiveness of Negative Pressure Wound Therapy Versus Conventional Dressing in the Treatment of Open Fractures A Systematic Review and Meta-Analysis. Journal of Orthopaedic Trauma. 2020 May; 34 (5): 223-230

Scientific Literature Review 

Reviewed By: Fernando Ramirez, DPM 
Residency Program: Kaiser SF Bay Area Foot & Ankle – Oakland, CA

Podiatric Relevance: Open fractures are challenging and complex injuries with high rates of morbidity due to contamination. The Gustilo-Anderson Type III fractures are particularly problematic due to large soft tissue deficit often leading to the need for delayed closure. The literature evaluating the benefits of negative pressure wound therapy (NPWT) between initial intervention and final surgery has no definitive conclusion. In 2018, the Wound Management of Open Lower Limb Fractures (WOLFF) trial was published, which found no significant differences in outcomes between NPWT and conventional dressings (CD). This meta-analysis reevaluated the safety and efficacy of NPWT in the treatment of open fractures.

Methods: A level I systematic review and meta-analysis was performed. The inclusion criteria captured articles that compared NWPT to CD for open fractures at any anatomical site of a skeletally mature patient that was not amendable to closure at initial debridement. The primary outcome of interest was deep infection including osteomyelitis. Secondary outcomes included flap frequency/failures, nonunion, amputation and length of hospital/ICU stay. Ten studies met the inclusion criteria for the meta-analysis. 
 

Results: Deep Infection was found in nine studies and 1095 patients. There were 55 infections in 614 patients in the NPWT group versus 84 infections in 481 patients with CD. These findings were statistically significant (P <0.001). When only including randomized control trials (six out of nine), there was no longer a statistically significant difference in the group utilizing NPWT. A subgroup analysis of two studies that used “sealed dressings”, meaning they were only opened in the operating room, demonstrated that there was no statistical difference in the rate of deep infections between the two groups. However, a second subgroup evaluating “unsealed dressings” demonstrated statically significant decrease of deep infections in the NPWT group. 

Flap frequency was identified in a total of 5 studies, and 474 patients, with 49/292 patients in the NPWT group, and 15/182 patients in the CD group, resulting in no statistical difference. Flap failure was evaluated by 4 studies, and found in 356 patients, 8/241 versus 11/115 flaps failed using NPWT and CD, respectively. There was a statistically significant reduction in flap failure in the NPWT group (P=0.04). Fracture nonunion was evaluated in four studies, and amputation rate in three studies both demonstrating no statistical differences between NPWT and CD. There was no statistical difference in length of hospital stay between the two groups. However, two of the studies, which were identified for evaluating length of ICU stay, found a significant reduction in length of ICU stay in favor of the CD group.

Conclusions: The author concludes that NPWT still remains superior to CD in preventing deep infections and flap failures. Contradicting the results from the WOLFF trial, the largest RCT on this topic to date. There are several confounding factors that can be influencing these results such as time to antibiosis and initial debridement as well as patient comorbidities. The literature is still inconclusive whether there is benefits for the use of NPWT versus CD in open fractures with delayed closure.