1. Bone Fractures Fracture—break in a bone Types of bone fractures
Closed (simple) fracture—break that does not penetrate the skin
Open (compound) fracture—broken bone penetrates through the skin
Bone fractures are treated by reduction and immobilization

2. Common Types of Fractures
Table 5.2

3. Repair of Bone Fractures
Hematoma (blood-filled swelling) is formed
Break is splinted by fibrocartilage to form a callus
Fibrocartilage callus is replaced by a bony callus
Bony callus is remodeled to form a permanent patch

4. Stages in the Healing of a Bone Fracture
Hematoma
Hematoma formation
Figure 5.5, step 1

5. Stages in the Healing of a Bone Fracture
Hematoma
External callus
New blood vessels
Internal callus (fibrous tissue and cartilage)
Spongy bone trabecula
Hematoma formation
Fibrocartilage callus formation
Figure 5.5, step 2

6. Stages in the Healing of a Bone Fracture
Hematoma
External callus
Bony callus of spongy bone
New blood vessels
Internal callus (fibrous tissue and cartilage)
Spongy bone trabecula
Hematoma formation
Fibrocartilage callus formation
Bony callus formation
Figure 5.5, step 3

7. Stages in the Healing of a Bone Fracture
Hematoma
External callus
Bony callus of spongy bone
Healed fracture
New blood vessels
Internal callus (fibrous tissue and cartilage)
Spongy bone trabecula
Hematoma formation
Fibrocartilage callus formation
Bony callus formation
Bone remodeling
Figure 5.5, step 4

8. The Axial Skeleton Forms the longitudinal axis of the body
Divided into three parts
Skull
Vertebral column
Bony thorax

9. The Axial Skeleton
Figure 5.6a

10. The Axial Skeleton
Figure 5.6b

11. The Skull Two sets of bones Bones are joined by sutures
Cranium
Facial bones
Bones are joined by sutures
Only the mandible is attached by a freely movable joint

12. Human Skull, Lateral View
Figure 5.7

13. Human Skull, Superior View
Figure 5.8

14. Human Skull, Inferior View
Figure 5.9

15. Human Skull, Anterior View
Figure 5.11

16. Paranasal Sinuses
Hollow portions of bones surrounding the nasal cavity
Functions of paranasal sinuses
Lighten the skull
Give resonance and amplification to voice

17. Paranasal Sinuses
Figure 5.10a

18. Paranasal Sinuses
Figure 5.10b

19. The Hyoid Bone
The only bone that does not articulate with another bone
Serves as a moveable base for the tongue
Aids in swallowing and speech

20. The Hyoid Bone
Figure 5.12