1. Calcium Bone is major reserve of calcium Calcium ions become available for other tissues –Bone must be destroyed to release the calcium Calcium-too high –Cardiac arrest Calcium-too low –Respiratory failure

2. Nerve function depends on calcium ions Enzymes need it as a cofactor (enzyme connection) Blood clotting is aided by calcium Bones help “buffer” these calcium levels

3. AGING AND SKELETON Bone is continually produced and lost Sex steroids (hormones) cause more loss –Menopausal women increase the chance for osteoporosis –Why not similar loss in men? Bone becomes more brittle –Loosing Collagen & hGH Bone looses mass –Affects teeth too

4. Exercise and Bone Bone has ability to alter its strength Stress causes bone to become stronger –Increases the mineral deposits & collagen Lack of exercise causes demineralization –Loss of bone minerals because they are not being replaced

5. Mechanical Stress Results from pull of skeletal muscles –Problem with bedridden patients –Bones in casts –Athletes have stronger bones! Pull of gravity –Astronauts Walking/ moderate weight lifting Epiphyseal plates & adolescents

6. Repair of Broken Bones Fractures –Partial – not fully broken into two pieces –Complete – broken into two or more pieces –Closed (simple) - the bone is broken, but the skin is intact. –Open (compound) - the bone exits and is visible through the skin Tobacco and nicotine increase the risk of bone fractures

7. http://www.lancastergeneral.org/content/greystone_36734.htm

8. Steps in Healing Hematoma is formed. –Ruptured vessels cause a blood-filled swelling. Fibrocartilage callus forms. –New capillaries grow. –Phagocytes (WBC) dispose of dead tissue. –Connective tissue forms and closes the gap.

9. Bony callus forms. –Osteogenic cells migrate into the area and multiply. –The fibrocartilage is replaced with bone. –This is spongy bone. Bone is remodeled. –Forms a permanent “patch.”

11. DISORDERS Osteoporosis –Condition of porous bones –Reduction of bone mass –Resorption outpaces deposition –Older females are more prone –Prevention is the best cure

12. Normal vs Osteoporosis

13. http://cbs5.com/health/rickets.childhood.disease.2.446155.html Rickets –Bone not being calcified –Bone becomes soft and rubbery –Vitamin D deficiency Herniated Disc –Ligaments become injured or weakened –Pressure ruptures the fibrocartilage –Material protrudes--herniates

15. Spina Bifida –Congenital defect (starts at birth) –Vertebral column laminae do not unite –Can cause paralysis –Absence of reflexes –Folic acid prevents this (when mother takes right from the start)

17. CONDITIONS Bunion –Deformity of big toe –Inflammation, bone spurs, calluses Kyphosis –Exaggeration of the thoracic curve of the vertebral column

18. Lordosis –Exaggeration of the lumbar curve in the vertebral column –Swayback Scoliosis –A sideways bending of the vertebral column –School testing

20. Osteogenic sarcoma –Bone cancer affecting osteoblasts –Femur, tibia, humerus of teenagers Sprain –Tearing or stretching of ligaments Strain –Stretching or partial tearing of a muscle

21. Rheumatoid arthritis –Autoimmune disease –Attackes cartilage and joint linings –Redness, swelling, pain, loss of function Osteoarthritis –Deterioration of articular cartilage –Wear & tear arthritis –Larger joints affected

22. Rheumatoid Arthritis