Objective assessment of endoscopic knot quality*

https://doi.org/10.1016/S0002-9610(97)00129-3Get rights and content

background

Studies of the surgeon's skill and the ergonomics of task performance in endoscopic surgery can be based on knot-tying tasks. The aim of this study was to establish an objective method for assessing the quality of surgical knots for use in such studies.

methods

In all, 2,700 surgeon's endoscopic knots were studied. Each knot was distracted using a tensiometer, and a computerized system analyzed force-extension curves. The breaking force was taken as an index of knot strength while the force integrated over the slope of the curve reflected knot tightening. A knot quality score (KQS) was obtained from the product of the knot-breaking force and the integrated force expressed as a percentage of the product for the untied ligature.

results

The mean breaking force (24 Newton ± 2.5) and integrated force (7.4 Newton ± 2.8) for broken knots were 71% and 35%, respectively, of those for united ligature. The integrated force yielded a narrower range of variability for untied ligature (SD 3.5% of mean) than for knots (SD 37% of mean). The KQS was higher for broken (25.3% ± 10.3%) than slipped knots (7.1% ± 5.1%).

conclusion

The KQS provides a reliable assessment of knot security and reflects the strength and degree of tightening of the knot.

References (6)

There are more references available in the full text version of this article.

Cited by (0)

*

This work was supported by a grant from the Scottish Office.

View full text