Fracture biomechanics and configuration

What are the 5 main forces that can act on any fracture

• Bending

• Torsion

• Tension

• Compression

• Shear

What force results in sharp angulation at the fracture site due to its 3 forces with 2 being at the end of the bone and one being in the center.

Bending force

What force causes the bone to rotate around an imaginary axis drawn through its longest part

Torsional force

In torsional force the ________ of bone rotate with respect to each other

fragments

What force can cause fragments to pull apart

Tension force

Tension force is usually counteracted by _______?

Soft tissue structures

________ acts as the opposite force to tension and with too much can cause overriding in unstable fractures

Compression force

_________ acts a component of compressive force along an oblique fracture line, ultimately causes the bone fragments to slide on each other

Shear force

What are the 6 possible types of fractures

• transverse

• oblique

• spiral

• comminuted

• segmental

• avulsion

a fracture of the perpendicular axis of the bone is known as a _______ fracture

transverse

A transverse fracture is typically the _____ of the bone

diameter

A transverse fracture is seen on a dog the force that would most typically cause this fracture is the _____ force

bending

A fracture that runs between the transverse and longitudinal aspects of the bone would be known as a _____ fracture

oblique

An oblique fracture can be less than or greater than 2x the bones _________

diameter

A dog with a fracture is brought in with his brother you note they both have fractures the older one has one that is 2x the bones diameter while the younger one has one that is shorter than 2x the bones diameter. What is the specific names of the fractures and what forces would be acting on them?

Older: long oblique

Younger: short oblique

shear force

An oblique fracture with a twist is commonly known as a _____ fracture

spiral

what force would cause a spiral fracture

Torsional force

A dog is brought in with a fracture that has cause the bone to break into 3 pieces this would be known as what type of fracture?

Comminuted fracture

A dog is brought in with a fracture that has separated the diaphysis of the femur from either end this would be known as what type of fracture

Segmental fracture

A piece of bone separated due to the pull of a ligament or tendon on the bone is known as an ______

avulsion

what locations doe avulsion typically happen at?

• tibial tubersoity

• greater trochanter

• olecranon

• calcenus

• acromion

• malleolus