Lee JM, Han YD, Cho MS, et al. - Researchers sought the parameters of the shape of pelvic floor muscle that impact the difficulty of total mesorectal excision (TME) and to present a predictive reference value for TME difficulty. They retrospectively studied 85 consecutive patients who had undergone curative resection for middle to lower rectal cancer from January 2015 to December 2015. Per multivariate analysis, independent predictors of surgical duration comprise body mass index, protective stoma, number of surgeon, and incline angle of pelvic floor muscle (β). The incline angle of pelvic floor muscle is a novel index having an independent predictive value for surgical duration. Test statistics of Mann–Whitney U for the difference in surgical duration between groups above and below a β of 54° were maximized. Transabdominal TME is thus expected to be difficult in cases with steeper incline of PFM.