1. December 12, 2014  Journal: What is the difference between a ball and socket joint and a hinge joint?

3. Bone Growth  Ossification - formation of bone in the body  Bones grow longitudinally to develop height and horizontally so they can better support our weight

4. Cells Involved in Bone Growth  Osteoprogenitor cells  Osteoblasts  Osteocytes  Osteoclasts

5. Osteoprogenitor Cells  Nonspecialized cells that can turn into other cells as needed  Found in the periosteum, endosteum, and the central canal of compact bones

6. Osteoblasts  Actually form the bones by secreting of calcium and other minerals that give a bone its usual characteristics  Developed from osteoprogenitor cells

7. Osteocytes  Mature bone cells  Developed from osteoblasts

8. Osteoclasts  Tears down bone material and help move calcium and minerals into the blood

9. Bone Development  Endochondral Ossification: Shaped cartilage is replaced by bone as a child grows older

10. Development Before Birth  Cartilage bone forms  Periosteum surrounds cartilage bone and the cartilage beings to break down  Spongy bone is created by osteoblasts Now called the primary ossification center  Compact bone begins to replace the spongy bone

11. Development After Birth  Long bones continue to grow  Secondary ossification begins with spongy tissue forming and not breaking down  Epiphyseal plate (growth plate): a thin band of cartilage forms between ossification centers to allow for continued growth Hormones control bone growth Eventually growth plate becomes ossified and growth stops

12. Natural Bone Deterioration  As the body ages the bones and cartilage deteriorates  Total bone mass also gradually decreases as we age as well

13. Osteoporosis  Disease where bone density decreases and tissues deteriorate  Causes bones to break more easily  Occurs in women four times more than men

14. Arthritis  Inflammation of the joints  Cartilage, tendons, and joints becomes less flexible and decreases the range of motion

15. Scoliosis  Abnormal curving of the spine which makes it appear in a ‘c’ or ‘s’ shape instead of a straight line

16. Types of Bone Fractures

17. Hairline Fracture  Fine, fracture that does not completely break the bone  Looks like a piece of hair on X-ray

18. Simple Fracture  Also known as a closed fracture  A break without a puncture to the skin

19. Spiral Fracture  When the bone is severely twisted

20. Greenstick Fractures  Incomplete breaks  Often occurs in children because they have softer bones than adults

21. Comminuted Fracture  Bone is crushed to the point that it becomes fragmented or splintered

22. Compound Fracture  Also known as an open fracture  When the bone is pushed through the skin  Deep tissues have the ability to be exposed to bacteria and infection can occur

23. How a Bone Heals  Bone breaks and severs the blood vessels within the bone  Blood leaking out of these vessels clots to form a fracture hematoma Helps stabilize the bone and line it up for mending  Bone dies without blood and dead cells are removed  Fracture hematoma develops tougher tissue and becomes a soft callus  Fibroblasts produce collagen which strengthens the soft callus  Osteoblasts produce bone cells which form a bone callus  Osteoclasts and osteoblasts work together to replace bone callus with harder compact bone