The primary objective of this study is to examine and compare the outcomes associated with the use of Flex HD®, a human acellular dermal matrix (HADM), and Strattice™, a porcine acellular dermal matrix, (PADM) when used as a reinforcing material in the repair of large complicated abdominal wall hernias.

At least 100,000 ventral hernia repairs are performed in the U.S. each year. Recently, biologically-based implants derived from acellular human dermis, porcine small intestinal submucosa, and porcine dermis have been reported in a variety of complex abdominal wall repair procedures. A variety of surgical techniques and implant placement methods have been described, with no one standard technique achieving precedence. Biologic implant reinforcement of a myofascial closure by means of component separation, or at a minimum, where three-layer fascial approximation is not possible, sublay placement (i.e., closure of the posterior rectus sheath under the implant) are described strategies. These techniques allow placement of the implant against an intact fascial layer and may improve implant incorporation into host tissue. However, the current literature shows few, if any, prospective, randomized, head-to-head comparisons of human acellular dermal matrix (HADM) allograft and porcine acellular dermal matrix (PADM) xenograft when used as a reinforcing material in the repair of large abdominal hernias by a component separation technique.

The Musculoskeletal Transplant Foundation (MTF) has manufactured and processed Flex HD Acellular Hydrated Dermis. This acellular dermis is derived from human skin. In complicated ventral hernia repairs, this type of graft tissue is necessary. Flex HD has been shown to reduce operative time, lower operative costs and provides minimal elasticity.

The primary objective of this study is to examine and compare the outcomes associated with the use of Flex HD®, a human acellular dermal matrix (HADM), and Strattice™, a porcine acellular dermal matrix, (PADM) when used as a reinforcing material in the repair of large complicated abdominal wall hernias.

Inclusion Criteria:

• 18 years of age or greater
• Have a BMI <40
• Have a hernia of at least 200 cm^2
• Have no contraindications to test material(s)
• Have a life expectancy greater than 1 year in the opinion of the Investigator
• Able to provide informed consent
• Able and willing to return for scheduled study visits over 1 year post-operatively (following research related surgery)

Exclusion Criteria:

• < 18 years of age
• Subject is determined to have an America Society of Anesthesiologists' (ASA) physical class of 4, 5, or 6.
• Have a BMI > 40
• Have a hernia < 2002 cm
• Have abdominal loss of domain such that the operation would be impractical or would adversely affect respiratory or cardiovascular function to an unacceptable degree in the opinion of the Investigator
• Inability to close the fascia primarily without abdominal wall mobilization or component separation
• Participation in an investigational drug or device study within the past 6 weeks prior to enrollment into this trial
• Have active necrotizing fasciitis or any other known active local or systemic infection
• Have a known collagen metabolism disorder or any medical condition that could interfere with normal tissue healing process as determined by the Investigator
• Have a known active malignancy present and/or had chemotherapy 12 weeks prior to screening or planned chemotherapy within 12 weeks of enrollment with the exception of BCC or SCC
• Have known moderate to severe cirrhosis which in the opinion of the Investigator would impact the outcome of this trial
• Have a life expectancy less than 1 year.
• Be unable to participate in the informed consent process
• Be unable or unwilling to return for scheduled study visits over the 1 year post-operative assessment period
• Subject's ventral hernia is related to an organ transplant surgery
• Received high dose steroids (≥100mg of prednisone) within the past 6 weeks
• Tobacco use within the past 6 weeks or positive serum cotinine test at time of admission
• Uncontrolled diabetes (i.e. known HbA1C value > 7%)
• History of drug addiction (recreational drugs, prescription drugs or alcohol) that in the Investigator's opinion may interfere with protocol assessments and/or the subject's ability to complete the required follow up
• Pregnancy and/or breastfeeding
• Enterocutaneous fistula
• Undergoing concomitant panniculectomy
• Ventral hernia repairs involving actively infected mesh removal
• Inability to obtain primary fascial closure (Intra-operatively)