The best approach for lateral incisional hernia is not known. Posterior component separation (reverse TAR) offers the possibility of using the retromuscular space for medial extension of the challenging preperitoneal plane.

The main objective of the study was to describe the surgical techniques used and their outcomes in the open lateral approach for the treatment of L3-L4 European Hernia Society (EHS) classification Incisional hernias, comparing the results between reverse TAR and pure lateral retromuscular preperitoneal, and analyzing the short- and long- term complications, including patient-reported outcomes measures (PROMs).

The study report followed the recommendations for reporting outcomes in abdominal wall hernias, and the new international classification of abdominal wall planes (ICAP).

A multicenter retrospective observational study was conducted using a prospectively maintained database from three university hospitals in Spain specialized in complex abdominal wall reconstruction. All patients undergoing open abdominal wall repair through the previous lateral incision for L3-L4 IHs between February 2012 and January 2020 were identified. All patients were operated on by the senior surgeons responsible for the complex abdominal wall units of each participating center. Prior to conducting the study, the approval of the local ethics committee was obtained (ID:39/2019). Written informed consent was also obtained.

The diagnosis of IH was based on clinical examination and imaging from a computed tomography (CT). The investigator only included patients with L3-L4 IHs. Patients with primary lateral hernias, such as Spiegel, Grynfelt and Petit hernias were excluded. We also excluded all patients in which the lateral IH was a parastomal hernia.

Demographic data, patient comorbidities, different classifications of hernia complexity, Carolinas Equation for Determining Associated Risks (CeDAR) and intraoperative and postoperative data were collected All patients followed a similar preoperative optimization program, which included endocrinologic and nutritional evaluations, respiratory physiotherapy, and abstinence from smoking at least 1 month before surgery. Weight loss was extremely recommended but without any mandatory prerequisite.

Inclusion Criteria:

• Patients with a lateral incisional hernia L3 European Hernia Society classification
• Patients with a lateral incisional hernia L4 European Hernia Society classification
• Patients older than 18 years old

Exclusion Criteria:

• Midline incisional hernia.
• Patients with a parastomal hernia
• Patients with a primary midline ventral hernia
• Patients with a primary lateral hernia.
• Age under 18 years old

All patients undergoing open abdominal wall repair through the previous lateral incision for L3-L4 IHs between February 2012 and January 2020 in the three University Hospitals in Spain involving in the multicentric study

We want to protect all the personal data of the patients participating in the study