1. Skeletal System PA 544 Clinical Anatomy Dr. Tony Serino

2. Skeletal System Composed of mineralized CT and their supporting structures including: bone, cartilage, ligaments, tendons, and bursae Functions: support, protection, homeostasis (specifically Ca ++ regulation) and hempoiesis

3. General Osteology Composition Cells –originate from mesechyme (undifferentiated mesodermal cells) Extracellular Matrix –Ground substances: water, salts, cementing substances, glycoproteins –Fibers: collagen and elastin

4. Cartilage Avascular CT Appositional and interstitial growth possible Chondroblast Chondrocyte Perichondrium Lacuna Matrix

5. Hyaline Cartilage

6. Elastic Cartilage

7. Fibrocartilage

8. Cartilage in Adult

9. Bone Heavily mineralized CT Highly vascular Principle storage area of Calcium Provides strength and structural support to body

10. Long Bone Anatomy Fig. 6.3

11. Compact vs. Spongy Bone Trabeculae

12. Bone Histology Fig. 6.5

13. Haversian System Lamellae

14. Ossification Development of bony tissues First bone to form is woven (premature) bone This is eventually replace by mature bone (compact or spongy bone) Two methods for creating bones: –Intramembraneous (bone replaces mesoderm membrane) –Endochondral (bone replaces an intervening cartilage model)

15. Intramembranous Ossification (membrane bone)

16. Endochondral Ossification (replacement bone)

17. Epiphyseal (Growth) Plate Reserve Cartilage (distal perichondrium) Proliferating Cartilage (Growth zone) Hypertrophic zone (Transforming zone) Calcified matrix (Osteogenic zone)

18. Epiphyseal Plate

20. Fracture Healing

21. Osteoporosis Normal Osteoporotic

22. Divisions of Skeletal System Axial Skeleton Fig. 7.1

23. Appendicular Skeleton Fig. 7.21

24. Types of Bones Long Bones

25. Short Bones

26. Flat Bones

27. Irregular bones

28. Sesamoid Bones

29. Accessory Bones: Wormian (Sutural) Bones and other supernumerary bones Results from failure of separate ossifications centers to fuse (common in foot and hand) Heterotropic bones – arise in soft tissue where bones not normally present

30. Articulations Functional Classifications –Synarthrotic (immovable) –Amphiarthrotic (slightly movable) –Diarthrotic (movable) Structural Classification –Fibrous –held by fibrous tissue –Cartilaginous –held by cartilage –Synovial –synovial cavity within joint

31. Suture (synarthrotic, fibrous joint) Found in bones of skull

32. Gomphosis (synarthrotic, fibrous) Ligament cemented to tooth surface

33. Syndesmoses (amphiarthrotic, fibrous)

34. Synchondroses (Synarthrotic, cartilaginous) Epiphyseal Plate

35. Synchondroses (synarthrotic, cartilaginous)

36. Symphyses (amphiarthrotic, cartilaginous) Includes pubic symphysis

37. Synovial = diarthrotic joints The synovial membrane filters the blood to create synovial fluid This fluid lubricates and nourishes the joint Some joints may have an additional wedge of cartilage within the joint (menisci) Fig. 8.3

38. Bursae and Tendon sheaths

39. Arthritis