Background: Transanal total mesorectal excision (TaTME) is associated with a relatively long learning curve. Force, motion, and time parameters are increasingly used for objective assessment of skills to enhance laparoscopic training efficacy. The aim of this study was to identify relevant metrics for accurate skill assessment in more complex transanal purse-string suturing. Methods: A box trainer was designed for TaTME and equipped with two custom made multi-DOF force/torque sensors. These sensors measured the applied forces in the axial direction of the instruments (Fz), instrument load orientation expressed in torque (Mx and My) on the entrance port, and the full tissue interaction force (Fft) at the intestine fixation point. In a construct validity study, novices for TaTME performed a purse-string suture to investigate which parameters can be used best to identify meaningful events during tissue manipulation and instrument handling. Results: Significant differences exist between pre- and post-training assessment for the mean axial force at the entrance port Fz (p = 0.01), mean torque in the entrance port Mx (p = 0.03) and mean force on the intestine during suturing Fft (p = 0.05). Furthermore, force levels during suturing exceed safety threshold values, potentially leading to dangerous complications such as rupture of the rectum. Conclusions: Forces and torque measured at the entrance port, and the tissue interaction force signatures provide detailed insight into instrument handling, instrument loading, and tissue handling during purse-string suturing in a TaTME training setup. This newly developed training setup for single-port laparoscopy that enables objective feedback has the potential to enhance surgical training in TaTME.

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Background: According to Dutch guidelines, locally excised, low-risk, pT1 or ypT0–1 rectal cancer should not necessarily be followed by completion total mesorectal excision (cTME) in contrast to rectal cancers with higher T stages or unfavorable features. This study evaluated cTME after local excision at a national level with possible determinants for decision-making. Methods: All patients in the Dutch Colorectal Audit (DCRA) who underwent local excision of rectal cancer between 2012 and 2015 were included. Guideline adherence for performing cTME was determined with univariate and multivariate analyses to identify factors related to noncompliance. Results: According to the guidelines, of 530 included patients, cTME was indicated in 283 (53%), and among those, was performed in 82 (29%). Guideline adherence for performing cTME improved significantly (P<.001), from 10% in 2012 to 44% in 2015. Lower Charlson comorbidity index in patients with high-risk pT1 rectal cancer and younger patients (aged 61–70 years vs ≥80 years) with pT≥2 rectal cancer were associated with increased performance of cTME (odds ratio [OR], 13.50; 95% CI, 1.39–131.32, and OR, 6.25; 95% CI, 1.83–21.31, respectively). Conclusions: In this population-based study from the Netherlands, only a minority of patients underwent cTME after local excision of rectal cancer with pathologic features indicating the need for further treatment according to the guidelines. Although the percentage of patients undergoing cTME increased over time, the study indicated a tendency toward rectal-preserving treatment with potential oncologic risks.@en