Oliver Varban, MD, Thomas Armstrong, PhD
University of Michigan Health System
INTRODUCTION: Prolonged static exertions during surgery can lead to stressful postures, musculoskeletal pain and fatigue. We used simulation to evaluate biomechanical stresses associated with laparoscopic surgery.
METHODS: Static loads imposed by the weight of body segments were estimated for a range of typical laparoscopic surgery postures using a 3D Static Strength Prediction Program (UM 3D SSPP). Previous studies show that localized fatigue and risk of chronic musculoskeletal disorders are related to relative loads on major muscle groups, which is expressed as percent of maximal voluntary contraction (%MVC) and is predicted by the UM 3D SSPP.
RESULTS: Low reaching postures during laparoscopy was defined as operating at 1m of elevation in a surgeon who is 1.75m in height. This stance results in higher levels of stress and fatigue on muscle groups associated with torso flexion (19%MVC), hip flexion (12%MVC), knee flexion (16%MVC) and ankle flexion (17%MVC). High reaching postures (operating at 1.5m of elevation) results in higher levels of stress and fatigue on wrist flexion (4%MVC), shoulder humeral rotation (8%MVC) and shoulder abduction (18%MVC). Positions that simulate a twisting stance during laparoscopy result in higher levels of stress on shoulder abduction (18%MVC), torso flexion (13%MVC), torso lateral bending (20%MVC), hip flexion (8%MVC), knee flexion (10%MVC) and ankle flexion (11%MVC).
CONCLUSION: Fatigue analysis predicts higher levels of stress on major muscle groups during laparoscopic surgery in low, high and twisting postures. Ideal body positioning that minimizes postural stress can lead to less musculoskeletal fatigue and may result in a reduction in errors during surgery.
Session: Poster Presentation
Program Number: P385