LAPAROSCOPIC INSTRUMENTS CAUSE INCREASED FOREARM FATIGUE - A SUBJECTIVE AND OBJECTIVE COMPARISON OF OPEN AND LAPAROSCOPIC TECHNIQUES

Background: Endoscopic surgery presents new ergonomic conditions for s urgeons that may cause fatigue and decreased performance during prolon ged laparoscopic procedures, This study uses a post-operative question naire and surface electromyography (EMG) to compare upper extremity di scomfort and muscle contraction during real and simulated laparoscopic and open surgical tasks. Methods: We asked surgeons to rank upper ext remity discomfort immediately following laparoscopic or open operation s on a scale of 0-3. We also measured the surface EMG activity of the right upper forearm flexor and extensor compartment, Deltoid and Trape zius muscles in three surgeons during simulated surgical tasks, The ma ximum voluntary contraction (MVC) for each muscle was used to normaliz e the data between subjects. Statistical comparisons were carried out using paired t-tests and P < 0.05. Results: Surgeons reported a signif icant increase in moderate/severe discomfort of the dominant foream fo llowing laparascopic operations. We found a significant increase in fo rearm flexor muscle contraction during tasks performed with the laparo scopic instrument compared to the haemostat (P = 0.01), Task repetitio n resulted in significant increases in the Deltoid (P = 0.02) and EDC (P = 0.05) muscle contractions with the laparoscopic instrument only. Conclusion: Use of laparoscopic instruments results in greater forearm discomfort, possibly due to the need for increased forearm flexor mus cle contractions compared to conventional surgical instruments. Furthe r studies and design changes are needed to optimize laparoscopic Instr ument design.