RESUMO
BACKGROUND: The modified medial Stoppa approach is an alternative and new surgical approach to access to the internal pelvis and medial wall of the acetabulum. There is little information about the clinical anatomic specifications of exposure in the literature. In this study, the pertinent surgical anatomy that involved the modified medial Stoppa approach was further defined and the anatomic positions and variations of the structures seen in the surgical site were analyzed. METHODS: We dissected five formalized cadavers to present structures at risk in a standard modified medial Stoppa approach. The internal iliac artery and branches were colored with latex injection in formalized cadavers. Morphometrical measurements of the neurovascular structures adjacent to quadrilateral surface and their anatomic variations were noted. RESULTS: It was detected that the obturator vessels and nerve and the iliolumbar vessels were primarily the structures at risk. Obturator vessels and nerve were the most important structures to pay attention because of their direct contact to quadrilateral surface. There was communication (corona mortis) between obturator and inferior epigastric veins in 4 (40%) of 10 hemipelvises. CONCLUSIONS: Before clinical applications, performing cadaver dissection is important to minimize intraoperative complications. This study was the first anatomic study in the literature that reveals the structures that are at risk during surgical treatment of acetabular fractures, which was treated with the modified medial Stoppa approach.