AlloDerm is an intact human tissue matrix with the critical biochemical and structural components of the dermal extracellular scaffold that enable it to recellularize and revascularize. Its biologic nature provides AlloDerm with an improved capacity to reintegrate with surrounding tissues and less inclination toward infection, erosion, extrusion, and rejection compared with synthetic tissue replacement materials. This retrospective review describes the experience with AlloDerm for incisional hernia and transverse rectus abdominis musculocutaneous flap reconstructions at a plastic surgery practice that handles complex, nonprimary repairs. AlloDerm was observed to provide exceptional safety and tolerability, and to become reintegrated and vascularized with surrounding tissue for tolerable and persistent tissue replacement.
Incisional hernia is a common and potentially morbid complication of abdominal surgery, with reported incidences ranging from 1 to 11%. 1-11 In fact, hernia surgery is the most common major operation performed by general surgeons in the United States today, 12 and the frequency of this complication is increasing at a rate of 1 to 2% per year, which is likely a result of longer and more complex operative procedures. 13,14 The success of secondary repair operations when an incisional hernia repair fails becomes increasingly less reliable than the first, with the chances of success diminishing with each successive repair attempt. For this reason, the secondary recurrence rate (or recurrence subsequent to hernia repair from the index operation), which can be as high as 50% in procedures attempting primary closure, can challenge the long-term outcome of thousands of surgical patients. 4,15,16
Several techniques for repair of incisional hernia have been described, including primary closure, use of autogenous fascial flaps, and placement of prosthetic implantable materials to fill the fascial defect or to reinforce primary abdominal tissues. 17-20 Despite much success using these methods, they carry substantial risk for harvesting, longevity, and breakdown complications over time. The introduction in 1958 of the woven polyethylene mesh Marlex, followed by similar plastic implantable prosthetic materials such as Mersilene and Gore-Tex, was a notable advance for surgery, and allowed tension-free repairs that, when used properly, substantially diminished recurrences after hernia repair procedures. Today these prostheses enjoy widespread use, but are associated with serious complications, including surgical site infection, fistula formation, bleeding, skin erosion, and drainage (seroma) issues, occurring in approximately 10 to 15% of cases. 21,22 Thus, attention has continued to focus in recent years on developing new materials and techniques for hernia repair that might further reduce the risk for recurrence and improve tolerability and acceptability of the prosthesis.
Most recently, an acellular human tissue product derived from donated human skin was developed (AlloDerm; LifeCell Corporation, Branchburg, NJ). AlloDerm is created by a patented procedure that eliminates cellular materials from the skin, leaving a matrix that retains a structurally intact basement membrane complex, intact collagen fibers and bundles to support tissue ingrowth, intact elastin filaments for biomechanical integrity, and the biochemical components necessary to initiate angiogenesis and cellular migration (Fig. 1). 23 The resulting tissue derivative is freeze-dried by a unique, proprietary method that prevents hexagonal ice crystallization, which can damage the matrix. The tissue can be stored for as long as 2 years in this freeze-dried form.
AlloDerm has been used for the treatment of severe burns and for the replacement of soft tissue, bladder support, skin and tympanic membrane grafting, and nasal septal reconstruction. The success of this alternative to traditional allografts and synthetic meshes in a variety of surgical settings, proof of its strength and tolerability in a rabbit model of abdominal wall repair, 24 combined with its inherent biocompatibility, provided a rationale for its use as a structural support for the repair of incisional abdominal hernias. In this practice, our early success with acellular tissue matrix led us to the use of this graft material for all subsequent abdominal wall and breast reconstruction repairs. Because of this unique experience and relatively large population managed over a concise period with AlloDerm, we performed a retrospective review of the cases completed since our switch to AlloDerm as the sole graft material. Although not a formal randomized clinical trial, we thought that a careful review of our experience would provide an early opportunity to evaluate the nature of the graft, the success of the repair, and the potential complications when using AlloDerm for these surgical procedures.