Noah J Switzer, MD, Mark A Dykstra, MD, Stephanie Lim, BSc, Erica Lester, MD, Richdeep S Gill, MD, PhD, Christopher De Gara, MB, MS, FRCSC, FACS, Xinzhe Shi, Daniel Birch, MD, FRCSC, Shahzeer Karmali, BSc, MD, MPH, FRCSC, FACS. Department of Surgery, University of Alberta, Edmonton, Alberta, Canada, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada, and Center for the Advancement of Minimally Invasive Surgery (CAMIS), Royal Alexandria Hospital.
Background and Objectives
The component separation technique (CST) was developed to improve the integrity of abdominal wall reconstruction for large, complex hernias. CST is based on the concept of reestablishing a functional abdominal wall by relaxing the external oblique aponeurosis bilaterally, allowing for a tension free midline fascial closure. Open CST, introduced in 1990, necessitates a large subcutaneous skin flap in the midline, and therefore is associated with significant wound complications, related to ischemia and infection. The endoscopic component separation technique (ECST) was developed in efforts to minimize wound complications. It has been suggested in preliminary studies to reduce wound complication rates post-operatively. To date, there have been no systematic reviews to assess the effectiveness of endoscopic versus open component separation. In this study, we systematically reviewed the literature comparing open versus endoscopic component separation and performed a meta-analysis of controlled studies.
A comprehensive search of electronic databases (e.g., MEDLINE, EMBASE, SCOPUS, Web of science and the Cochrane Library) using search terms “component separation” was completed. All randomized controlled trials, non-randomized comparison study, case series were included. All human studies limited to English were included. Two independently reviewers screened abstracts, reviewed full text versions of all studies classified and extracted data. All comparison studies included in the meta-analysis were assessed independently by two reviewers for methodological quality using the Cochrane Risk of Bias (RoB) tools. Disagreements were resolved by re-extraction, or third party adjudication. Where possible and appropriate, a meta-analysis was conducted.
64 primary studies (3200 patients) were identified that met our inclusion criteria for the systematic review and were assessed by full manuscript; no randomized controlled trials, 8 controlled studies and 56 case series. Endoscopic CST compared to open CST was shown to have lower mean rates of superficial wound infections (5.0% vs 10.4%), skin dehiscence (2.8% vs 7.2%), necrosis/debridement (4.1% vs 6.1%), hematoma/seroma formation (4.0% vs 9.9%), fistula tract formation (1.0% vs 1.5%), fascial dehiscence (0.0% vs 0.4%) and mortality (0.1% vs 0.7%. The open component CST did have lower rates of intraabdominal abscess formation (3.0 vs 4.3%) and recurrence rates (10.1% vs 12.9%).
The meta-analysis included 8 non-randomized controlled studies (412 patients). Endoscopic CST was associated with a significantly decreased rate of fascial dehiscence (Odds ratio= 3.18, p=0.02). In addition similar trends were found that suggested endoscopic CST has decreased wound infection rates (Odds ratio=1.61), necrosis (Odds ratio=1.44), and hematoma/seroma formation (Odds ratio= 1.93), however these did not reach statistical significance.
This systematic review and meta-analysis comparing ECST to open CST suggests ECST is associated with decreased overall post-operative wound complication rates including superficial infections, hematoma/seroma formation, necrosis, fistula formation, and both skin and fascial dehiscence. Further prospective studies are needed to verify these findings.