Smaller hands and less experience are associated with greater ergonomic strain during endoscopic procedures.

INTRODUCTION Up to 89% of physicians who routinely perform endoscopy experience some type of musculoskeletal pain. In this study, we sought to quantitatively analyze provider factors that influence ergonomic strain during live endoscopic procedures. METHODS Surface electromyography (sEMG) was used to measure ergonomic strain on physicians while performing upper and lower endoscopies. EMG data were normalized to a maximal voluntary contraction (MVC) recording for each muscle group, yielding a %MVC value. Subgroup analyses were performed based on glove size, physician training level, specialty, and handedness. RESULTS A total of 165 upper (n = 68) and lower (n = 97) endoscopies were recorded. Endoscopists with small hand sizes had significantly higher ergonomic strain in the left anterior and posterior forearm muscle compartments as compared to endoscopists with medium or large hands (%MVC L-anterior: small: 9.1 ± 1.1; medium: 6.4 ± 1.2; large: 5.9 ± 1.6; p < 0.001); (%MVC L-posterior: small: 12.0 ± 0.8; medium: 9.4 ± 1.3; large: 8.8 ± 1.4; p < 0.001). Additionally, upper body muscle groups had significantly higher ergonomic strain in endoscopists with less lifetime endoscopic experience (%MVC R-trapezius: expert: 8.4 ± 1.2; novice: 9.3 ± 1.2; p < 0.05); (%MVC R-deltoid: expert: 6.1 ± 1.4; novice: 8.5 ± 1.3; p < 0.001). There were no significant ergonomic differences between surgeons or gastroenterologists and no differences between right- and left-handed dominant individuals. CONCLUSIONS Endoscopists with small hands experienced great ergonomic strain in their left forearm. Our data support the widely held belief that "one size does not fit all" and will hopefully spark change in the design of future endoscopes by device manufacturers. Our data also support that the experience level of the endoscopist contributed significantly to ergonomic performance, likely due to postural differences leading to decreased upper body strain. Therefore, it remains critically important to educate young proceduralists on strategies for ergonomic relief early in his or her endoscopic training program that can ameliorate ergonomic strain that accrues over the lifetime of a physician's career.