Biomechanics

• applies mechanics to biology

• physiological and medical applications are the main points in this

course

Biomechanics

”Biomechanics is the science that examines forces acting upon and within a biological structure and effects produced by such forces.”

B.M. Nigg

Historical backgroundLeonardo da Vinci, 1452-1519Andreas Vesalius, 1514-1564Galileo Galilei, 1564-1642William Harvey, 1578-1658René Descartes, 1596-1650Giovanni Alfonso Borelli, 1608-1679Robert Boyle, 1627-1691Robert Hooke, 1635-1703Isac Newton, 1642-1727Leonard Euler, 1707-1783Thomas Young, 1773-1829Jean Poiseuille, 1797-1869Adolf Fick, 1829-1901....

Leonardo da Vinci

Andreas Vesalius

Giovanni Alfonso Borelli

The way of solving a Biomechanical problem

1. How does the construction work mechanically ?

0. Description of the anatomy, the CAD-drawing.

Kinematics

AnatomyLimitations

2. What about the loading ?

Outer forces

Equations of equilibrium (forces) Equations of equilibrium (moments)

2. What about the loading?

Internal forces

Loading

Loading

Bending

TensionCompression

Ligament

Cartilage

Bending

TensionCompression

It is not obvious that the position follows unambiguous from the loading …

ONLY PASSIVE ELEMENTS

The position is given from the loading

WITH ACTIVE ELEMENTS

The position can be com-pletely different even if the loading is the same

3. Constitutive relations

Mechanical properties of themost important constituentsof bone, muscles, tendons, ligaments, cartilage etc.

STRAIN

STRESS

STRESSCOMPACT BONE (APATITE AND COLLAGEN TENDON

(COLLAGEN)

STRAIN