1. Skeletal System
Axial Skeleton

2. Axial Skeleton
Includes 80 bones of the skull, vertebral column and bony thorax
Functions:
Supports head, neck & trunk
Protects brain, spinal cord and thoracic organs

3. Skull Composed of flat bones Function:
Used for attachment of head muscles & protects the brain

4. Sutures of the Skull
Sutures: interlocking joints that unite skull bones
Coronal: where parietal bones meet frontal
Sagittal: where 2parietal bones meet superiorly
Squamos: where parietal and temporal bones meet on lateral aspects of skull
Lambdoidal: where parietal bones meet occipital bones meet posteriorly

6. Vertebral Column aka the Spine
Location: runs from the base of the skull to the coccyx (tailbone)
Function:
Surrounds and protects the spinal cord
Provides attachment sites for ribs and back muscles

7. Vertebral Column Characteristics 26 interconnected irregular bones
Provides a flexible, curved structure
Serves as axial support of the trunk

8. Vertebral Column Curvatures of the Spine:
S-shaped to prevent shock to head in motion
Allows for trunk flexibility
Increases resiliency & flexibility of the spine
Functions like a spring, not a rod
Cervical & Lumbar Curves: concave posteriorly
Thoracic & Sacral Curves: convex posteriorly

9. Curvatures of the Spine

10. Abnormal Curvatures of the Vertebral Column
Lordosis: aka sway back
An accentuated lumbar curve
Kyphosis: aka hunchback
An exaggerated thoracic curve
Scoliosis: the twisted disease
An abnormal lateral curvature in the thoracic region
Typical in girls in late childhood

11. Lordosis & Kyphosis

12. Scoliosis

13. Cervical Vertebrae
7 total extending from base of skull to ~ shoulder line
Numbered C1-C7
Smallest & lightest vertebrae
Unique vertebrae
Atlas or C1: no body; holds the occipital bone, allows nodding motion (“yes”)
Axis or C2: acts as a pivot for rotation; shake head (“no”)

14. Thoracic Vertebrae 12 total; runs through mid-back Numbered T1-T12
Larger than cervical
Longer, palpable spinous processes
Ribs attach here posteriorly

15. Lumbar Vertebrae 5 total Numbered L1-L5
Huge bodies and short spinous processes
Holds most of body weight & stress; very sturdy

16. Sacrum & Coccyx Sacrum Coccyx Formed from 5 fused vertebrae
Numbered S1-S5
Makes up posterior wall of pelvis
Strengthens & stabilizes pelvis
Coccyx
4 fused vertebrae

17. Ligaments of the Spine There are several; only 2 you need to know
Anterior Longitudinal Ligament: resists back hyperextension
Posterior Longitudinal Ligament: resists back flexion

18. Intervertebral Discs Cushion-like pads between vertebrae
Asts as shock absorbers during motion
Makes up ~25% of length of column
Flattens during the day

19. Intervertebral Discs

20. Ribs Flat bones 12 total pairs Attach posteriorly to thoracic spine
Function:
Protect thoracic organs
True Ribs: the superior 7 pairs
Attach directly to sternum by costal cartilage
False Ribs: the inferior 5
8-10: join each other by cartilage and indirectly attach to sternum
11& 12: the floating ribs, no anaterior attachment

21. Rib Cage

22. Pelvis Has 2 regions: true and false pelvises
False pelvis superior to true pelvis
True pelvis dimensions are a concern to child-bearing women
Pelvic structure differs between men and women

24. Gender Difference of Pelvis
Men
Narrow outlet
Heavier & thicker bone structure
Ilia less flared, more vertical
Sacrum long and curved
Ischia close together
Less rounded pubic arch
Women
Inlet circular & large
Pelvis shallow, lighter & thinner
Ilia flare laterally
Sacrum shorter & less curved
Ischia farther apart & shorter
Pubic arch is more rounded

25. Female vs. Male Pelvis

26. Female vs. Male Skulls

27. FUNTION OF JOINTS They hold bones together.
Allow the rigid skeleton mobility
Joints are classified in 2 ways:
Functionally –amount of movement
Structurally – type of tissue

28. Functionally- amount of movement
1. Synarthrosis- immovable
Ex) sutures in skull
2. Amphiarthrosis- slightly movable
Ex) intervertebral joints
3. diarthrosis-freely movable
Ex) limbs

29. Structurally- tissue type between bones
1) Fibrous- connected by fibrous tissue
- sutures skull
2) Cartilaginous- connected by cartilage
-pubic symphysis
3) Synovial- separated by a joint containing fluid
-6 types based on articulating bone surface

30. Types of Synovial Joints
1. Plane Joint-wrist
2. Hinge Joint- elbow
3. Pivot Joint- ulna & radius
4. Condyloid Joint- metacarpels
5. Saddle Joint- thumb
6. Ball & Socket- shoulder or hip

37. Stress Fracture of the Tibia

43. STAGES OF BONE REPAIR