Inverse dynamic analysis of the biomechanics of the thumb while pipetting: A case study

• Published in: Medical engineering & physics Vol. 34; no. 6; pp. 693 - 701
• Main Authors: Wu, John Z, Sinsel, Erik W, Gloekler, Daniel S, Wimer, Bryan M, Zhao, Kristin D, An, Kai-Nan, Buczek, Frank L
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.07.2012; Elsevier
• Subjects: Applied physiology; Biological and medical sciences; Biomechanical Phenomena; Carpometacarpal Joints - metabolism; Carpometacarpal Joints - physiology; Computerized, statistical medical data processing and models in biomedicine; Energy Metabolism; Ergonomics; Ergonomics. Work place. Occupational physiology; Female; Human physiology applied to population studies and life conditions. Human ecophysiology; Humans; Joint moment; Kinematics; Laboratories; Mechanical Phenomena; Medical sciences; Metacarpophalangeal Joint - metabolism; Metacarpophalangeal Joint - physiology; Modeling; Models and simulation; Movement; Pipette; Radiology; Thumb; Thumb - physiology; Ergonomics; Modeling; Thumb; Pipette; Kinematics; Joint moment; Osteoarticular system; Biomechanics; Moment; Joint; Biomedical engineering; Inverse problem
• ISSN: 1350-4533; 1873-4030
• DOI: 10.1016/j.medengphy.2011.09.012

Abstract Thumb-push manual pipettes are commonly used tools in many medical, biological, and chemical laboratories. Epidemiological studies indicate that the use of thumb-push mechanical pipettes is associated with musculoskeletal disorders in the hand. The goal of the current study was to evaluate the kinematics and joint loading of the thumb during pipetting. The time-histories of joint angles and the interface contact force between the thumb and plunger during the pipetting action were determined experimentally, and the joint loadings and joint power in the thumb were calculated via an inverse dynamic approach. The moment, power, and energy absorption in each joint of the thumb during the extraction and dispensing actions were analyzed. The results indicate that the majority of the power is generated in the interphalangeal (IP) and carpometacarpal (CMC) joints for the pipetting action. The analysis method and results in the current study will be helpful in exploring the mechanism for musculoskeletal injuries of the hand associated with pipetting, providing a preliminary foundation for ergonomic design of the pipette.