Differences between experts and trainees in the motion pattern of the dominant upper limb during intracorporeal endoscopic knotting

Background: Very little research has been carried out on the ergonomics of surgeon-instrument interface, The aim of this study is to investigate the e ffect of experience on the motion pattern of the dominant upper limb during endoscopic intracorporeal knot tying. Methods: Two groups of 5 surgeons (e xpert consultants and higher surgical trainees) tied 360 surgeon's knots in side an endoscopic trainer in a random sequence. Motion analysis at the elb ow and shoulder joints of the dominant upper limb was carried out using 3-d imensional kinemetrix system. Each knot was distracted using a tensiometer. The endpoints were the execution time, knot quality score, angular velocit y and range of movement. Kruskal-Wallis one-way analysis of variance and Ma nn-Whitney U test were used for analysis. Results: The expert group had a b etter knot quality score (p < 0.005) and shorter execution time (p < 0.0001 ) than beginners. Motion analysis at the shoulder joint showed that experts had a higher angular velocity (p < 0.05) and a wider range of movement wit h more adduction (p < 0.01) compared to beginners. No significant differenc es were found at the elbow. Conclusion: The better task performance by expe rt surgeons is associated with controlled rapid manipulations and a wider r ange of movement at the shoulder joint of the dominant upper limb. Copyrigh t (C) 2000 S. Karger AG, Basel.