The purpose of this study is to measure the changes in tension after each release in a standard posterior component separation during abdominal wall reconstruction.

Myofascial component separation techniques are purported to reduce tension in abdominal wall reconstruction, but few objective data exist regarding tension reduction with posterior component separation (PCS) techniques. PCS techniques include several unique steps: division of the posterior rectus sheath, division of the posterior lamella of the internal oblique aponeurosis, and transversus abdominis release. Each of these releases carries a certain amount of morbidity, including neurovascular injuries, posterior sheath breakdowns, and musculofascial disruptions resulting in lateral hernias, and thus should only be undertaken if necessary to achieve physiologic tension. More importantly, during a PCS, the surgeon must achieve posterior elements apposition in the midline to allow an adequate pocket to deploy the mesh and avoid breakdown and interstitial hernias and recurrences. Further, the anterior sheath should be reapproximated to complete a functional abdominal wall reconstruction. During each procedure, the surgeon must assess the tension on the posterior closure and decide whether further release is necessary to achieve a safe, durable repair of the posterior elements.

Demographic information, including patient age, gender, BMI, history of diabetes, chronic immunosuppression, smoking history, and history of prior ventral hernia repairs will be captured in the Abdominal Core Health Quality Collaborative (ACHQC), per the investigators' practice standard. Additional intraoperative information collected will be hernia size, extent of posterior component separation, mesh size and type, and location of mesh placement. The ACHQC is a hernia-specific, nationwide registry for quality improvement, featuring prospectively-collected, surgeon-entered data.

The aim of this study is to determine the changes in abdominal wall tension with progressive PCS in abdominal wall reconstruction. The investigators also aim to quantify the reduction in tension on both the anterior and posterior elements of a PCS.

Inclusion Criteria:

• Candidates for abdominal wall reconstruction
• Patients able to provide informed consent

Exclusion Criteria:

• Patients unable to provide informed consent

All patients undergoing abdominal wall reconstruction with posterior component separation.