1. Modeling the Musculoskeletal Biomechanics of the Human Arm
Introduction
Modeling the Musculoskeletal Biomechanics of the Human Arm
B.E.A.R.S Presentation
Brian A. Garner Assistant Professor
Department of Engineering
Textbook pictures from:
Nigg, Benno M. and Herzog, W., Biomechanics of the Musculoskeletal System 2nd edition, Chichester and New York: Wiley, 1999
Anatomy pictures from:
Marieb, Elaine N., Human Anatomy & Physiology 4th
edition, Addison Wesley Longman, Inc. 1998

2. Musculoskeletal Modeling
Model represents:
Bone and Joint Mechanics/Dynamics
Muscle Lines-of-Action
Muscle Physiological Properties
Muscle Activation Dynamics
Model calculations:
Force
Acceleration
F = M * A
Acceleration
Force
A = F / M

3. Anatomical Database Medical Images from Visible Human Project:
CT Images
Cryo-Section Images

4. Anatomical Database
3D Image Reconstruction:

5. Anatomical Database
Reconstructed Bones
and Muscles

6. Skeletal Anatomy of Arm
Carpals
Metacarpals
Phalanges
Clavicle
Scapula
Humerus
Ulna
Radius
Clavicle
Scapula

7. Ball-and-Socket Joint Behavior
Skeletal Anatomy of Arm
Carpals
Metacarpals
Phalanges
Clavicle
Scapula
Humerus
Ulna
Radius
Ball-and-Socket Joint Behavior

8. Shoulder Joint Model

9. Revolute (Hinge) Joint Behavior
Skeletal Anatomy of Arm
Carpals
Metacarpals
Phalanges
Clavicle
Scapula
Humerus
Ulna
Radius
Revolute (Hinge) Joint Behavior

10. Forearm Joints

11. Scapulothoracic Articulation
Clavicle
Scapula

12. Musculoskeletal Modeling
Model represents:
Bone and Joint Mechanics/Dynamics
Muscle Lines-of-Action
Muscle Physiological Properties
Muscle Activation Dynamics
Model calculations:
Force
Acceleration
F = M * A
Acceleration
Force
A = F / M

13. Muscular Anatomy of Arm

14. Muscular Anatomy of Arm

15. Muscular Anatomy of Arm

16. Muscle Force Action
Hypothetical Muscle:
Hypothetical Model:

17. Muscle Path Obstacle Models
A number of simple geometric shapes were used to represent the shapes of underlying structures: single cyl, single sphere, double cyl, stub
each muscle path was given its own set of obstacles
path of muscle computed as shortest distance between attachment sites around obstacles

18. Muscle Force Action Reconstructed Muscle Centroid Line-of-Action
Modeled Muscle Path

19. Muscle Force Action
Other Modeled Muscle Paths:

20. Muscle Force Action
Shoulder Muscles:
Forearm Muscles:

21. Muscle Force Action
Supraspinatus
Biceps Brachii

22. Musculoskeletal Modeling
Model represents:
Bone and Joint Mechanics/Dynamics
Muscle Lines-of-Action
Muscle Physiological Properties
Muscle Activation Dynamics
Model calculations:
Force
Acceleration
F = M * A
Acceleration
Force
A = F / M

23. Muscle Physiology

24. Muscle Physiology

25. Muscle Physiology

26. Muscle Physiology

27. Muscle Physiology

28. Muscle Physiology

29. Modeling Muscle Physiology
Physiological Parameters:
Force vs. Length
maximum isometric force
optimal muscle
fiber length
pennation
angle
rest length of tendon

30. Modeling Muscle Physiology
Optimization of Parameters:

31. Modeling Muscle Physiology