Background: The management of incisional hernias outside the midline remains a challenging procedure. Evidence-based data and even any kind of guidelines for dealing with this problem are still lacking. The aim of the study was to elucidate this field of hernia surgery and give some guidelines for retromuscular sublay mesh repair outside the midline.
Materials and methods: Fresh-frozen corpses were used to perform anatomical studies. During all the investigations the main target was to find the layer which can maintain the maximum overlap of healthy tissue with the implanted mesh material. Afterwards the findings were evaluated during clinical situations, using photo-documentation and drawings.
Results: The layer between the external oblique muscle and the internal oblique muscle is the ideal place to position the mesh with adequate overlap. Even for subcostal hernias, this layer offers adequate mesh overlap behind the ribs. For lumbar hernias the same plane of dissection is usually useful. Only if the defect is situated close to the bone might preperitoneal dissection and mesh placement be necessary.
Conclusion: The repair of lateral hernias must follow the same principles as median sublay repair. With sufficient knowledge of the anatomical layers of the abdominal wall, adequate mesh overlap can be achieved for any kind of lateral hernia. Therefore the retromuscular sublay repair can be regarded as the standard procedure for all types of hernia outside the midline.