Biomechanics of the upper limbs : mechanics, modeling, and musculoskeletal injuries

The repetitive tasks of various forms of manual work can lead to cumulative trauma disorders, increasing staff burn-out rates and the number of sick-days taken by employees. In addition, interest in upper extremity musculoskeletal disorders has grown as the service sector has claimed a larger share of the workforce. These factors introduce the need for an up-to-date text that combines basic biomechanics with practical bioengineering issues. Biomechanics of the Upper Limbs: Mechanics, Modeling, and Musculoskeletal Injuries is an engineering oriented book focusing on upper extremity musculoskeletal disorders, as opposed to the more general introductions to cumulative trauma disorders and medical management related books. It covers musculoskeletal components of the upper extremities, their models, and the measurement and prediction of injury potential. Students and professionals will find it provides an excellent basic grounding in the subject.Topics include:A basic introduction to biomechanical principlesGross structure of the musculoskeletal system, including bone and soft tissueOrganization of muscles and muscle anatomy, types of fibers, contractile theories, and muscle receptorsModeling of muscle mechanicsModels of the upper limbsTypes of musculoskeletal disorders and the scientific evidence for risk factors, as well as epidemiologyInstrumentation for motion, pressure, force and nerve conduction measurements, and electromyographyJob and worksite analysisHand toolsOffice environment seating and computer devices Preface......Page 6 The Author......Page 8 Acknowledgements......Page 10 Contents......Page 12 1.1 What Is Biomechanics?......Page 20 1.2 Basic Concepts......Page 21 1.3 Coordinate Systems......Page 22 1.4 Force Vector Algebra......Page 24 1.5 Static Equilibrium......Page 27 1.6 Anthropometry and Center of Mass Determination......Page 33 1.7 Friction......Page 39 1.8 Dynamics......Page 42 Questions......Page 47 Problems......Page 48 References......Page 50 2.1 Gross Overview of Movements......Page 52 2.2 The Skeletal System......Page 54 2.3 Mechanical Properties of Bone......Page 59 2.4 Soft Connective Tissue......Page 63 2.5.1 Articular Joints......Page 65 2.5.2 Joint Lubrication......Page 68 2.5.4 Cartilaginous Joints......Page 69 Problems......Page 71 References......Page 72 3.1 Introduction to Musculature......Page 74 3.2 Structure of Muscle......Page 76 3.3 Basic Cell Physiology......Page 78 3.4 The Nervous System......Page 82 3.5 The Excitation-Contraction Sequence......Page 84 3.6.1 Types of Motor Units......Page 87 3.6.2 Motor Unit Twitch......Page 88 3.7.1 Active Length-Tension Relationship......Page 91 3.7.2 Passive Length-Tension Relationship......Page 92 3.7.3 Velocity-Tension Relationship......Page 93 3.7.5 Developments Leading to Hill’s Muscle Model......Page 95 3.7.6 Fatigue and Endurance......Page 97 3.8 Energy, Metabolism, and Heat Production......Page 98 3.9 Receptors......Page 102 3.9.1 Muscle Spindles......Page 103 3.9.2 Golgi Tendon Organs......Page 104 3.9.3 Other Receptors......Page 106 3.10 Reflexes and Motor Control......Page 107 3.10.1 Stretch Reflex......Page 108 3.10.2 g-Loop Control......Page 109 3.10.3 a-g Coactivation......Page 112 3.10.5 Clasp-Knife Reflex......Page 113 3.10.6 Other Polysynaptic Reflexes......Page 114 Questions......Page 115 References......Page 117 4.1 Laplace Transforms and Transfer Functions......Page 120 4.1.1 Partial Fraction Expansion......Page 121 4.1.2 Transfer Functions......Page 127 4.2 Viscoelastic Theory......Page 128 4.3 Hill’s Muscle Models......Page 135 4.3.1 Active Muscle Response......Page 138 4.3.2 Tension Buildup......Page 140 4.3.3 Stress Relaxation......Page 142 4.3.4 Creep......Page 143 4.3.5 Time Constant......Page 144 4.4 Frequency Analysis......Page 145 4.4.1 Generalized Approach......Page 146 4.4.2 Magnitude and Phase Angle in the Frequency Domain......Page 147 4.4.3 Magnitude and Phase Angle in the Laplace Domain......Page 152 4.5 Frequency Analysis of Passive Muscle......Page 155 4.6 Hatze’s Multielement Model......Page 157 4.7 Applications of the Hatze Muscle Model......Page 168 4.8.1 Basic Concepts......Page 169 4.8.2 First-Order System......Page 171 4.8.3 Second-Order System......Page 172 4.8.4 Human Information Processing and Control of Movements......Page 179 4.9.1 The Root Locus Method......Page 183 4.9.2 Muscle Spindle Model......Page 195 4.9.3 Time Delays......Page 200 4.9.4 Velocity Control......Page 203 4.9.5 Reflex Stiffness......Page 204 Questions......Page 208 Problems......Page 209 References......Page 210 5.1.1 Bones of the Hand and Wrist......Page 214 5.1.2 Joints of the Hand......Page 215 5.1.3 Muscle of the Forearm, Wrist, and Hand......Page 216 5.1.4 Flexor Digitorum Profundus and Flexor Digitorum Superficialis......Page 217 5.1.5 Flexor Tendon Sheath Pulley Systems......Page 219 5.1.6 Wrist Mechanics......Page 220 5.1.7 Select Finger Anthropometry Data......Page 223 5.2 Static Tendon-Pulley Models......Page 225 5.3 Dynamic Tendon-Pulley Models......Page 229 5.4.1 Reduction Methods......Page 231 5.4.2 Optimization Methods......Page 232 5.4.3 Combined Approaches......Page 233 5.5 A Two-Dimensional Hand Model......Page 234 5.6 Direct Measurement Validation Studies......Page 240 5.7 Critical Evaluation of Modeling Approaches......Page 242 Questions......Page 246 References......Page 247 6.1 The Extent of the Problem......Page 252 6.2 Common MSDs and Their Etiology......Page 253 6.2.1 Tendon Disorders......Page 255 6.2.2 Muscle Disorders......Page 256 6.2.3 Nerve Disorders......Page 258 6.2.5 Bursa Disorders......Page 261 6.3 Medical Diagnosis and Treatment of MSDs......Page 262 6.4.1 Introduction to Epidemiology......Page 269 6.4.2 Statistical analyses......Page 277 6.4.3 Multivariate Modeling......Page 286 6.4.4 Quality of Epidemiological Research......Page 292 6.5.1 Neck Disorders......Page 294 6.5.2 Shoulder Disorders......Page 299 6.5.4 Hand/Wrist - Carpal Tunnel Syndrome......Page 301 6.5.5 Hand/Wrist - Tendinitis......Page 305 6.6 The Scientific Research and Evidence for Psychosocial Risk Factors......Page 307 6.7 Iatrogenesis - A Contrarian View......Page 310 Questions......Page 313 Problems......Page 315 References......Page 318 7.2.1 Types of Measurement Devices......Page 330 7.2.2 Calibration Methods......Page 332 7.2.3 Static Measurements - Range of Motion......Page 335 7.2.4 Dynamic Measurements - Angular Velocity and Acceleration......Page 336 7.3.1 Early Pressure Devices......Page 339 7.3.2 Force Sensing Electronic Components......Page 341 7.3.3 Integrated Touch Glove System......Page 346 7.4.1 Basic Concepts......Page 349 7.4.2 Nerve Stimulation and Recording......Page 351 7.4.3 Response Measures......Page 356 7.4.4 Limitations......Page 358 7.5 Electromyography......Page 360 7.5.1 EMG Instrumentation......Page 362 7.5.2 EMG Analysis......Page 363 Questions......Page 370 References......Page 371 8.1 The Need for Job Analysis......Page 380 8.2.1 Basic Concepts......Page 381 8.2.2 Reliability of Assessments......Page 382 8.2.3 Reliability of Analysts......Page 384 8.2.4 Accuracy and Precision......Page 389 8.2.5 Applications......Page 392 8.3.1 Initial Steps......Page 395 8.3.2.2 Body Discomfort Maps......Page 396 8.3.2.3 Subjective Ratings......Page 398 8.4.1 Early Recording of Postures......Page 399 8.4.2 OWAS......Page 400 8.4.3 Posture Targeting......Page 402 8.4.5 Video Posture Analyses......Page 403 8.4.6 Task Analyses......Page 406 8.5.1 Checklists......Page 408 8.5.3 OCRA......Page 413 8.6 Data-Driven Upper Limb WRMSD Risk Index......Page 419 Questions......Page 426 Problems......Page 427 References......Page 429 9.1.1 Historical Development of Tools......Page 436 9.1.3 General Tool Principles......Page 437 9.2.1 Anatomy and Types of Grip......Page 438 9.2.2 The Biomechanics of a Power Grip......Page 439 9.2.3 The Biomechanics of a Precision Grip......Page 442 9.2.4 Measurement of Skin Coefficient of Friction......Page 444 9.2.5 Grip Force Coordination......Page 445 9.2.6 Static Muscle Loading......Page 447 9.2.7 Awkward Wrist Position......Page 449 9.2.9 Repetitive Finger Action......Page 450 9.3.2 Handle Diameter......Page 451 9.3.3 Handle Shape......Page 452 9.3.5 Angulation of Handle......Page 454 9.4.1 Grip Span......Page 455 9.4.3 Handedness......Page 457 9.5.2 Weight......Page 458 9.5.6 Miscellaneous......Page 459 9.6.1.2 Shovel Load......Page 460 9.6.1.3 Throw Height......Page 461 9.6.1.5 Posture......Page 462 9.6.1.9 Handle Material......Page 463 9.6.1.11 Blade Size, Shape, and Thickness......Page 464 9.6.2.1 Length and Striking Efficiency......Page 465 9.6.2.2 Weight and Striking Efficiency......Page 467 9.6.2.3 Other Considerations......Page 468 9.6.3.2 Pulling vs. Pushing......Page 469 9.6.4.2 Wheelbarrows......Page 470 9.7.1 Pliers......Page 471 9.7.2 Screwdrivers......Page 472 9.7.3 Knives......Page 473 9.7.4 Meat Hooks......Page 474 9.7.5.1 Power Drills......Page 476 9.7.5.2 Nutrunners......Page 477 9.7.5.3 Handle Sizes......Page 478 9.7.6 Railroad Tools......Page 479 9.7.8.2 Surgical Instruments......Page 480 9.7.8.6 Scissors......Page 481 Questions......Page 482 References......Page 483 10.1 General Musculoskeletal Problems......Page 492 10.2.1 Seated Posture......Page 493 10.2.1.1 The Spine......Page 494 10.2.1.2 Disc Compression Forces......Page 496 10.2.1.3 Electromyography......Page 497 10.2.2.1 Standard Posture......Page 498 10.2.2.2 Screen Height......Page 500 10.2.2.5 Alternate Posture......Page 502 10.2.3.2 Postural Changes......Page 503 10.2.3.4 Subjective Assessment......Page 504 10.2.4.1 Seat Pressure Distribution......Page 506 10.2.4.2 Sores and Ulcers......Page 507 10.2.4.3 Adaptive Seats......Page 508 10.2.5.1 Sit-Stand Chairs......Page 509 10.2.5.2 Trunk-Thigh Angle......Page 510 10.2.5.3 Forward-Sloping Chairs......Page 511 10.2.5.5 Compromise Seat Pan......Page 513 10.2.6.1 Work Surface Height......Page 514 10.2.6.2 Line of Sight......Page 516 10.2.6.3 Tilted Work Surface......Page 518 10.2.6.5 Workspace Envelope......Page 519 10.3.1.1 Keyboard Slope......Page 520 10.3.1.2 Keyboard Profile......Page 521 10.3.1.3 Key Size, Displacement, and Resistance......Page 522 10.3.1.4 Key Feedback......Page 523 10.3.2.1 Standard Keyboard Problems......Page 525 10.3.2.3 Performance Effects......Page 527 10.3.3.2 Dvorak Layout......Page 528 10.3.3.3 Other Layouts......Page 529 10.3.5 Numeric Keypads......Page 530 10.4.1 Cursor Positioning......Page 532 10.4.2 The Mouse......Page 533 10.4.3 Mouse Alternatives......Page 536 10.5 Notebooks and Handheld PCs......Page 537 10.6.1 Rest Pauses......Page 538 10.6.2 Exercises......Page 539 Questions......Page 541 References......Page 542 Glossary......Page 560 Name Index......Page 590 Subject Index......Page 610

the Repetitive Tasks Of Various Forms Of Manual Work Can Lead To Cumulative Trauma Disorders, Increasing Staff Burn-out Rates And The Number Of Sick-days Taken By Employees. In Addition, Interest In Upper Extremity Musculoskeletal Disorders Has Grown As The Service Sector Has Claimed A Larger Share Of The Workforce. These Factors Introduce The Need For An Up-to-date Text That Combines Basic Biomechanics With Practical Bioengineering Issues.

biomechanics Of The Upper Limbs: Mechanics, Modeling, And Musculoskeletal Injuries Is An Engineering Oriented Book Focusing On Upper Extremity Musculoskeletal Disorders, As Opposed To The More General Introductions To Cumulative Trauma Disorders And Medical Management Related Books. It Covers Musculoskeletal Components Of The Upper Extremities, Their Models, And The Measurement And Prediction Of Injury Potential. Students And Professionals Will Find It Provides An Excellent Basic Grounding In The Subject.

topics Include:

a Basic Introduction To Biomechanical Principles

gross Structure Of The Musculoskeletal System, Including Bone And Soft Tissue

organization Of Muscles And Muscle Anatomy, Types Of Fibers, Contractile Theories, And Muscle Receptors

modeling Of Muscle Mechanics

models Of The Upper Limbs

types Of Musculoskeletal Disorders And The Scientific Evidence For Risk Factors, As Well As Epidemiology

instrumentation For Motion, Pressure, Force And Nerve Conduction Measurements, And Electromyography

job And Worksite Analysis

hand Tools

office Environment Seating And Computer Devices

"An engineering oriented book focusing on upper extremity musculoskeletal disorders, as opposed to the more general introductions to cumulative trauma disorders and medical management related books. It covers musculoskeletal components of the upper extremities, their models, and the measurement and prediciton of injury potential"--Back cover This text focuses on the upper extremity, the musculoskeletal components, their models, and the measurement and prediction of injury potential. Students and professionals should find it provides an excellent basic grounding to the subject