Soft Tissue Injury Management With a Continuous External Tissue Expander Gabriel F. Santiago, MD,* Benjamin Bograd, MD,* PatrickL. Basile, MD,*Þþ Robert T. Howard, MD,*Þ Mark Fleming, DO,* and Ian L. Valerio, MD, MS, MBA*Þþ Background: Blast exposure is a common cause of soft tissue injury within the battlefield setting, with the extremities often critically involved. The resulting injury pattern presents with massive soft tissue defects that may be further complicated by varying degrees of accompanying orthopedic and peripheral nerve damage. To address the severe soft tissue defect, various combinations of advanced reconstructive methods are typically required to achieve definitive wound coverage. Continuous external tissue expansion has been used by our institution to significantly reduce wound burden and provide for definitive wound closure in certain blast-injured patients. Methods: The authors present an early series of 14 patients who suffered massive extremity soft tissue injuries and were treated with an external tissue expansion system (DermaClose RC). Outcome measurements included time to definitive closure and method of definitive wound closure. A 5-patient subset of this group was prospectively analyzed to determine measurements including initial wound surface area (WSA), percentage reduction in WSA, and related complications. Results: Overall time to wound coverage ranged from 1 to 6 days, with mean time to wound coverage being 4.4 days. Of the 14 patients included in the series, 12 (85.7%) were able to undergo delayed primary closure, whereas 2 required split thickness skin grafting. In the 5-patient subgroup, WSA initially ranged from 20.25 to 1031.25 cm 2 . Mean wound size was 262.7 cm 2 . Decrease in WSA ranged from 44% to 93% of the initial WSA, with mean decrease being 74.3% (95% confidence interval, 57.33Y91.3). Conclusions: In the management of large complex wounds, external tissue expansion has proven to be a valuable adjunct in achieving definitive wound closure. It can often aid in successful delayed primary closure of certain soft tissue wounds, has low associated morbidities, and can reduce the need for more complex or morbid procedures when used properly. The authors propose an algorithm for the use of continuous external tissue expansion system to achieve effective and successful wound closure, while potentially reducing the need for increased donor-site morbidities associated with more complex or larger reconstruction measures. Key Words: external tissue expansion, tissue creep, biologic creep, soft tissue wound management, tissue expansion, fasciotomy treatment, postsurgical wound management (Ann Plast Surg 2012;69: 418Y421) C omplex soft tissue extremity wounds secondary to blast expo- sure are common injuries suffered in times of war and acts of terrorism. 1Y3 These soft tissue injuries are often composite-type defects, have significant projectile particulate material penetration, and have varying degrees of underlying and surrounding tissue damage because of blast wave transmission. Additionally, ongoing tissue necrosis as well as infections related to the contaminated soft tissue wound bed can further complicate such injuries. 4,5 Given the aforementioned issues, effective management of the soft tissue component in these wounds can be rather challenging to those trauma and reconstructive surgeons involved in their management. 1Y5 Reconstructive surgeons must be adept at applying the prin- ciples of the reconstructive ladder and/or elevator based on the coverage needs of the blast trauma patient. Numerous options have been proposed to effectively address these traumatic wounds, including secondary intention healing, delayed primary closure, skin grafting with or without use of dermal regenerates, local or regional flaps, free tissue transfer, or various combinations of the previously mentioned options, depending on the complexities of the particular blast injury. Additional methods previously explored and described consist of tissue expansion techniques, although with varying degrees of success. 6,7 Both internal and external tissue expansion devices have been used to address complex soft tissue injuries, with some of the earliest descriptions of their use dating back to 1904. 8 Internal tissue expansion typically consists of the use of sili- cone implants, which are placed subcutaneously and serially ex- panded over various time intervals. These devices have been used successfully for reconstruction of various head and neck, breast, abdominal wall, and extremity defects. 7,9Y11 As an alternative to internal tissue expansion, external tissue expansion measures rely on the application of an external force to the underlying skin and its related subcomponents. Typically, these expansion methods use differing tensioning devices that are often secured to the periphery of the wound, whereas other expansion devices use negative pres- sure therapies within the internal aspects or inner areas of a wound to reduce wound size. As the external forces are applied to the overlying skin and underlying attached structures, several cytoskel- etal, extracellular, enzymatic, membrane, and cytosolic components converge to produce a biochemical response that results in an over- all increase of tissue mass. This overall process and biochemical response has been termed biological creep. 12 Both internal and external tissue expanders take advantage of the skin’s inherent ability to undergo mechanical and biological creep, thus potentially pro- viding for successful wound closure in certain applications. 13Y15 Mechanical creep is the relatively immediate increase in length of the same mass of tissue, whereas biological creep is the increase in tissue mass that is a direct response to a stretch stimulus. 12,16 Examples of prior external expander systems include Jacob’s ladder, use of rubber banding, and numerous retention suture methods. All of these methods apply force or tension to a wound edge CLINICAL P APERS 418 www.annalsplasticsurgery.com Annals of Plastic Surgery & Volume 69, Number 4, October 2012 Received January 6, 2012, and accepted for publication, after revision, January 9, 2012. From the *Walter Reed National Military Medical Center, Bethesda, MD; †Division of Plastic and Reconstructive Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA; and ‡Department of Plastic and Reconstructive Surgery, Johns Hopkins University, Baltimore, MD. Presented at the 28th Annual Meeting of the Northeastern Society of Plastic Surgeons, Amelia Island, FL, October 20Y23, 2011. Conflicts of interest and sources of funding: Neither Dr Valerio nor his associated coauthors have received anything of value from or owns stock in a commercial company or institution related directly or indirectly to the subject of this article. Views expressed in this article are those of the authors and do not reflect the official policy or position of the Department of the Navy, Department of De- fense, nor the US Government. Reprints: Ian L. Valerio, MD, MS, MBA, Plastic and Reconstructive Surgery Service, Walter Reed National Medical Center, 8901 Wisconsin Ave, Bethesda, MD 20889. E-mail: ian.valerio@med.navy.mil; iv_cwru@yahoo.com. Copyright * 2012 by Lippincott Williams & Wilkins ISSN: 0148-7043/12/6904-0418 DOI: 10.1097/SAP.0b013e31824a4584 Copyright © 2012 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.