Masayuki Ishii1,2, Atsushi Shimizu3, Alan Kawarai Lefor3, Yujirou Kokado4, Hideaki Nishigori4, Yasuko Noda5. 1. Department of Anatomy, Bio-imaging and Neuro-cell Science, Jichi Medical University, Tochigi, Japan. m.ishii0104@shinkohp.or.jp. 2. Colorectal and Pelvic Surgery Division, Shinko Hospital, 1-4-47, Wakinohamacho, Chuo-Ku, Kobe, Japan. m.ishii0104@shinkohp.or.jp. 3. Department of Surgery, Jichi Medical University, Tochigi, Japan. 4. Colorectal and Pelvic Surgery Division, Shinko Hospital, 1-4-47, Wakinohamacho, Chuo-Ku, Kobe, Japan. 5. Department of Anatomy, Bio-imaging and Neuro-cell Science, Jichi Medical University, Tochigi, Japan.
Abstract
PURPOSE: The term "lateral rectal ligament" in surgery for rectal cancer has caused confusion regarding its true existence and contents. In previous studies, investigators claimed the existence of the ligament and described its topographical features as neurovascular structures and their surrounding connective tissues located at the anterolateral aspect of the distal rectum or the posterolateral aspect of the middle rectum. The purpose of this study is to evaluate the structure of the so-called "lateral rectal ligament" in cadaver dissections. METHODS: Dissection was performed in nine cadavers (eight males and one female, aged 73 to 94 years) in accordance with typical total mesorectal excision techniques. During dissection, structures related to "the ligament" were examined and images recorded. RESULTS: At the anterolateral aspect of the distal rectum, the middle rectal artery was noted to be crossing the fusion of Denonvilliers' fascia and the proper rectal fascia. At the posterolateral aspect of the middle rectum, there was a structure which consisted of the rectal nerves running through the fusion of the pelvic fasciae. Although called "ligaments," neither structure contained discrete strong connective tissue fixing the rectum to the pelvic wall. CONCLUSIONS: The proper rectal fascia and surrounding pelvic fasciae fuse firmly anterolaterally and posterolaterally where neurovascular structures course toward the rectum. During a total mesorectal excision, the surgical dissection plane coincides with the fused part of the fasciae, which had long been considered the "lateral rectal ligament."
PURPOSE: The term "lateral rectal ligament" in surgery for rectal cancer has caused confusion regarding its true existence and contents. In previous studies, investigators claimed the existence of the ligament and described its topographical features as neurovascular structures and their surrounding connective tissues located at the anterolateral aspect of the distal rectum or the posterolateral aspect of the middle rectum. The purpose of this study is to evaluate the structure of the so-called "lateral rectal ligament" in cadaver dissections. METHODS: Dissection was performed in nine cadavers (eight males and one female, aged 73 to 94 years) in accordance with typical total mesorectal excision techniques. During dissection, structures related to "the ligament" were examined and images recorded. RESULTS: At the anterolateral aspect of the distal rectum, the middle rectal artery was noted to be crossing the fusion of Denonvilliers' fascia and the proper rectal fascia. At the posterolateral aspect of the middle rectum, there was a structure which consisted of the rectal nerves running through the fusion of the pelvic fasciae. Although called "ligaments," neither structure contained discrete strong connective tissue fixing the rectum to the pelvic wall. CONCLUSIONS: The proper rectal fascia and surrounding pelvic fasciae fuse firmly anterolaterally and posterolaterally where neurovascular structures course toward the rectum. During a total mesorectal excision, the surgical dissection plane coincides with the fused part of the fasciae, which had long been considered the "lateral rectal ligament."