Section 19: Fracture Mechanics and Breaks 19-1 FIGURE 32-6 - - PowerPoint PPT Presentation

Section 19: Fracture Mechanics and Breaks

19-1

FIGURE 32-6 Skeletal injuries may be open or closed.

19-2 From: Spotsylvania

19-3 From: Garner

Marieb, 2004

19-4 From: Seeley

Basic Forces Causing Fracture Basic Forces Causing Fracture

• Compression

Compression

• Tension
• Transverse Loading

Transverse Loading

• Torsion

19-5 From: Justice

Tensile Loading

19-6 From: Brown

Compression Loading

19-7 From: Brown

Shear Loading

19-8 From: Brown

19-9 From: Al-Tayyar

19-10 From: Al-Tayyar

Fracture Types

• Fractures are often classified according to the position of the bone

ends after the break:

Open (compound) bone ends penetrate the skin. Closed (simple) bone ends don’t penetrate the skin. Comminuted bone fragments into 3 or more pieces Common Comminuted bone fragments into 3 or more pieces. Common

in the elderly (brittle bones).

Greenstick bone breaks incompletely. One side bent, one side

broken Common in children whose bone contains more collagen

• broken. Common in children whose bone contains more collagen

and are less mineralized.

Spiral ragged break caused by excessive twisting forces. Sports

injury/Injury of abuse injury/Injury of abuse.

Impacted one bone fragment is driven into the medullary space

• r spongy bone of another.

19-11 From: Imholtz

19-12 From: Seeley

19-13 From: Imholtz

19-14 From: Seeley

19-15 From: Seeley

What kind of fracture is this? It’s kind of tough to tell, but hi i f this is a _ _ _ _ _ _ fracture.

19-16 From: Imholtz