Occupational Biomechanics

DON B. CHAFFIN, PhD, is a Distinguished University Professor of Industrial and Operations Engineering, Biomedical Engineering, and Occupational Health; and Director of the Human Motion Simulation Laboratory at the University of Michigan. GUNNAR B. J. ANDERSSON, MD, PhD, is Chairman and Professor of Orthopedic Surgery at the Rush University Medical Center in Chicago, Illinois.BERNARD J. MARTIN, PhD, DSc, is Associate Professor of Industrial and Operations Engineering and research fellow in the Division of Kinesiology at the University of Michigan.

"This excellent book written by the most prominent authors in the field is a must have for all professionals in this field." (The Applied Ergonomics International News)

• Foreword. Preface. Acknowledgments. 1. Occupational Biomechanics as a Specialty. 1.1 Definition of Occupational Biomechanics. 1.2 Historical Development of Occupational Biomechanics. 1.2.1 Kinesiological Developments. 1.2.2 Developments in Biomechanical Modelling. . 1.2.3 Developments in Anthropometry. 1.2.4 Methods for Evaluating Mechanical Work Capacity. 1.2.5 Developments in Bioinstrumentation. 1.2.6 Developments in Motion Classification and Time Prediction Systems. 1.3 The Need for an Occupational Biomechanics Specialty. 1.3.1 Epidemiological Support for Occupational Biomechanics. 1.3.2 Social and Legal Support for Occupational Biomechanics. 1.3.3 Ergonomic Support for Occupational Biomechanics. 1.4 Who Uses Occupational Biomechanics?. 1.5 Organization of The Book. Review Questions. References. 2. The Structure and Function of the Musculoskeletal System. 2.1 Introduction. 2.2 Connective Tissue. 2.2.1 Ligaments, Tendons, and Fascia. 2.2.2 Cartilage. 2.2.3 Bone. 2.3 Skeletal Muscle. 2.3.1 The Structure of Muscles. 2.3.2 The Molecular Basis of Muscle Contraction. 2.3.3 The Energy Metabolism of Muscle. 2.3.4 The Nerve Impulse Causing Muscle Contraction. 2.3.5 Mechanical Aspects of Muscle Contraction. 2.3.6 Muscle Fatigue. 2.3.7 Quantification and Prediction of Fatigue. 2.4 Joints. 2.4.1 The Synovial Joint. 2.4.2 Joint Lubrication. 2.4.3 Osteoarthritis. 2.4.4 Intervertebral Discs. Review Questions. References. 3. Anthropometry in Occupational Biomechanics. 3.1 Measurement of Physical Properties of Body Segments. 3.1.1 Body-Segment Link Length Measurement Methods. 3.1.2 Body-Segment Volume and Weight. 3.1.3 Body-Segment Locations of Center of Mass. 3.1.4 Body-Segment Inertial Property Measurement Methods. 3.2 Anthropometric Data for Biomechanical Studies in Industry. 3.2.1 Segment Link Length Data. 3.2.2 Segment Weight Data. 3.2.3 Segment Mass-Center Location Data. 3.2.4 Segment Moment-of-inertia and Radius-of-Gyration Data. 3.3 Summary Of Anthropometry in Occupational Biomechanics. Review Questions. References. 4. Mechanical Work Capacity Evaluation. 4.1 Introduction. 4.2 Joint Motion: Methods and Data. 4.2.1 Methods of Measuring Joint Motion. 4.2.2 Normal Ranges of Joint Motion. 4.2.3 Factors Affecting Range-of-Motion Data. 4.3 Muscle Strength Evaluation. 4.3.1 Definition of Muscular Strength. 4.3.2 Static and Dynamic Strength-Testing Methods. 4.3.3 Population Muscle Strength Values. 4.3.4. Personal Factors Affecting Strength. 4.4. Summary and Limitations of Mechanical Work-Capacity Data. Review Questions. References. 5. Bioinstrumentation for Occupational Biomechanics. 5.1 Introduction. 5.2 Human Motion Analysis Systems. 5.2.1 Basis for Measuring Human Motion. 5.3 Muscle Activity Measurement. 5.3 .1 Applied Electromyography. 5.3.2 Mechanomyography. 5.3.3 Intra Muscular Pressure. 5.4 Muscle Strength Measurement Systems. 5.4.1 Localized Static Strength Measurement Systems. 5.4.2 Whole-body Static Strength Measurement System. 5.4.3 Whole-body Dynamic Strength Measurement System. 5.5 Intradiscal Pressure Measurement. 5.5.1 Measurement Concept. 5.5.2 Intradiscal Pressure Measurement System. 5.5.3 Applications and Limitations in Occupational Biomechanics. 5.6 Intra-abdominal (Intragastric) Measurements. 5.6.1 Measurement Development. 5.6.2 Measurement System. 5.6.3 Applications and Limitations in Occupational Biomechanics. 5.7 Seat Pressure Measurement Systems. 5.8 Stature Measurement System. 5.9 Force Platform System. 5.10 Foot and Hand Force Measurement Systems. 5.11 Measurement of Vibration in Humans. Review Questions. References. 6. Occupational Biomechanical Models. 6.1 Why Model?. 6.2 Planar Static Biomechanical Models. 6.2.1 Single-Body-Segment Static Model. 6.2.2 Two-Body-Segment Static Model. 6.2.3 Static Planar Model of Nonparallel Forces. 6.2.4 Planar Static Analysis of Internal Forces. 6.2.5 Multiple-link Coplanar Static Modeling. 6.3 Three-dimensional Modeling of Static Strength. 6.4 Dynamic Biomechanical Models. 6.4.1 Single-Segment Dynamic Biomechanical Model. 6.4.2 Multiple-Segment Biodynamic Model of Load Lifting. 6.4.3 Coplanar Biomechanical Models of Foot Slip Potential While Pushing a Cart. 6.5. Special-purpose Biomechanical Models of Occupational Tasks. 6.5.1 Low-Back Biomechanical Models. 6.5.2 Biomechanical Models of the Wrist and Hand. 6.5.3 Modeling Muscle Strength. 6.6 Future Developments in Occupational Biomechanical Models. Review Questions. References. 7. Methods Of Classifying And Evaluating Manual Work. 7.1 Traditional Methods. 7.1.1 Historical Perspective. 7.2 Traditional Work Analysis System. 7.2.1 MTM: An Example of a Predetermined Motion?Time System. 7.2.2 Benefits and Limitations in Contemporary Work Analysis Systems. 7.3 Contemporary Biomechanical Job Analysis. 7.3.1 Identification of Musculoskeletal Injury Problems. 7.3.2 Analyzing Biomechanical Risk Factors. 7.3.3 Specialized Biomechanical Risk Factor Evaluation. 7.3.4 EMGs in Job Evaluation. 7.4 Future Impact of Occupational Biomechanics on Work Analysis Systems. Review Questions. References. 8. Manual Material-handling Limits. 8.1 Introduction. 8.2. Lifting Limits In Manual Material Handling. 8.2.1 Scope of NIOSH Work Practices Guide for Manual Lifting. 8.2.2 Basis and Structure of the 1994 NIOSH-Recommended Weight-lifting Limit. 8.2.3 Example of NIOSH RWL Procedure. 8.2.4 Comments on the Status of the NIOSH Lifting Guide. 8.2.5 Alternative Recommendations for Evaluating Manual Lifting Tasks. 8.3 Pushing and Pulling Capabilities. 8.3.1 Foot-Slip Prevention During Pushing and Pulling. 8.4 Asymmetric Load Handling. 8.4.1 Toward a Comprehensive Manual Material-Handling Guide. 8.5 Recommendations for Improving Manual Materials Handling Tasks. 8.6 Summary of Manual Material-Handling Recommendations and Evaluation Methods. Review Questions. References. 9. Guidelines For Work In Sitting Postures. 9.1 General Considerations Related to Sitting Postures. 9.2 Anthropometric Aspects of Seated Workers. 9.3 Comfort. 9.4 The Spine and Sitting. 9.4.1 Clinical Aspects of Sitting Postures. 9.4.2 Radiographic Data. 9.4.3 Disc Pressure Data During Sitting. 9.4.4 Muscle Activity. 9.4.5 Sitting Postures and The Spine. 9.5 The Shoulder and Sitting. 9.6 The Legs and Sitting. 9.7 The Sitting Workplace. 9.7.1 The Office Chair. 9.7.2 The Table in a Seated Workplace. 9.7.3 Visual Display Terminal Workstations. 9.8 Summary. Review Questions. References. 10. Biomechanical Considerations in Machine Control and Workplace Design. 10.1 Introduction. 10.1.1 Localized Musculoskeletal Injury in Industry. 10.2 Practical Guidelines for Workplace and Machine Control Layout. 10.2.1 Structure-Function Characteristics of the Shoulder Mechanism. 10.2.2 Shoulder-Dependent Overhead Reach Limitations. 10.2.3 Shoulder-and Arm-Dependent Forward Reach Limits. 10.2.4 Neck?Head Posture Work Limitations. 10.2.5 Torso Postural Considerations in Workbench Height Limitations. 10.2.6 Biomechanical Considerations in the Design of Computer Workstations. 10.3 Summary. Review Questions. References. 11. Hand-Tool Design Guidelines. 11.1 The Need for Biomechanical Concepts In Design. 11.2 Shape and Size Considerations. 11.2.1 Shape for Avoiding Wrist Deviation. 11.2.2 Shape for Avoiding Shoulder Abduction. 11.2.3 Shape to Assist Grip. 11.2.4 Size of Tool Handle to Facilitate Grip. 11.2.5 Finger Clearance Considerations. 11.2.6 Gloves. 11.3 Hand-Tool Weight and Use Considerations. 11.4 Force Reaction Considerations in Powered Hand-tool Design. 11.5 Keyboard Design Considerations. 11.5.1 Posture Stress. 11.5.2 Keying Exertion Force Repetition. 11.6 Summary. Review Questions. References. 12. Guidelines for Whole-Body and Segmental Vibration. 12.1 Definitions and Measurement. 12.1.1 Definitions. 12.1.2 Measurement of Vibration. 12.2 General Effects of Vibration on Human Beings. 12.3 Whole-Body Vibration. 12.3.1 Effects of Low-frequency Vibration. 12.3.2 Effects of Middle-frequency Vibration. 12.3.3 Biomechanical Effects on the Spine. 12.3.4 Physiological Responses. 12.4 Hand?Arm Vibration. 12.4.1 Transmission of Vibration in the Upper Extremity. 12.4.2 Hand?Arm Vibration Syndrome. 12.5 Sensorimotor Effects. 12.6 Vibration Exposure Criteria. 12.6.1 Whole-Body Vibration Recommendations. 12.6.2 Hand-Arm Vibration Recommendations. 12.7 Control and Prevention. Review Questions. References. 13. Worker Selection, Training and Personal Protective Device Consideration. 13.1 Worker Selection. 13.1.1 Introduction to Worker Selection. 13.1.2 History and Physical Examination. 13.1.3 Radiographic Preplacement Examination. 13.1.4 Quantitative Physical Preplacement Screening. 13.2 Preplacement Training. 13.2.1 General Content of Training. 13.2.2 How Workers Should Be Trained. 13.3 Biomechanical Aspects of Back Belts. 13.3.1 Passive Stiffness Effects of Back Belts. 13.3.2 Abdominal Pressure Effects of Back Belts. 13.3.3 Reduced Torso Mobility Effects Due to Back Belts. 13.4 Job Rotation and Psychosocial Stress. 13.5 Summary. Review Questions. References. 14. Summary. Appendix A. Part 1: Anatomical and Anthropometric Landmarks as Presented by Webb and Associates. Part 2: Glossary of Anatomical and Anthropometric Terms. Appendix B Population weight and Mass-Center data. Table B.1 Segment Weight Values Derived from Regression Equations Using Total Body Weight as the Independent Variable. Table B.2 Anatomical Location of Segment Centers of Gravity (Centers of Mass). Table B.3 Segment Moments of Inertia. Table B.4 Joint Center Locations and Link Definitions. Appendix C Terms and Units of Measurement in Biomechanics. Appendix D NIOSH 1994 Tables. Appendix E Push and Pull Force Tables. Appendix F Data Gathering ? Job Risk Factors. Appendix G Some General Web Sites that Complement. References in Text. Index.