How does ergonomic positioning for microlaryngeal surgery (MLS) affect muscle fatigue and pain in the upper back, cervical, and arm muscles?
Background: Musculoskeletal symptoms associated with performing MLS are common, and there is a lack of insight regarding good ergonomics during this surgery. Surgeons unknowingly place themselves at higher risk of musculoskeletal injury if accommodations to avoid pain, muscle fatigue, and number of repetitions associated with MLS are not evaluated and compensated for.
Explore this issue:March 2015
Study design: Individual randomized counterbalanced design study on 18 otolaryngology residents/fellows.
Setting: Training program at the University of Pittsburgh Voice Center, University of Pittsburgh School of Medicine, Penn.
Synopsis: Participants were trained to perform a simulated surgical task consisting of bimanual, ambidextrous, sequential, and repetitive vocal-fold palpation with blunt laryngeal dissectors. Participants performed a simulated surgical task for 15 minutes without stopping, took a 15-minute break, and then repeated the task in a different ergonomic position. Rapid Upper Limb Assessment scores were significantly different between favorable and unfavorable positions, and the number of microbreaks was statistically different between the two. Participants in the favorable position completed significantly more task repetitions. The greatest average electromyographic amplitude differences between positions were noted for the lower trapezius and cervical trapezius, with increased amplitude in the unfavorable position. On average, participants reported greater pain in the unfavorable position; pain was significantly greater in the unfavorable position for the anterior shoulder and posterior shoulder. Participants found the favorable position much easier to use.
Bottom line: There is electromyographic evidence of decreased muscle activation and fatigue and self-reported pain with a more favorable microsurgical ergonomic position. This may help surgeons avoid musculoskeletal injuries.