Skeletal System Study Questions

Contentious Bones                                    

     Your 80 year-old great aunt, Persis, was placing a canning jar on the top shelf of her pantry when she stepped awkwardly off the stool and twisted her leg at the hip.  She felt a sharp pain in her hip and, after collapsing to the floor, found she could no longer stand.  She was taken to the emergency room where an X ray showed that the neck of her femur was fractured.  More detailed X ray images revealed reduced bone mass in the head and neck regions of the injured femur, in the ends of other long bones of the body and in the vertebrae.  Surgery was necessary to repair the fractured femur and a biopsy of the bone tissue indicated that the composition of the osteoid was normal.  Healing of the fractured femur is proceeding slowly.

     1. What organ(s) is(are) involved?

     2. What primary tissue type is involved?

     3. What specific type of tissue is affected?

     4. What specific types of cells produce the normal microanatomy of the tissue?

     5a.What is the significance of your great aunt's age and gender?

     5b. What normally happens to the microanatomy of the specific tissue you identified as it ages?

     6. What age-related alterations in the activities of the cells you identified cause this change in microanatomy?

     7. What is the significance of your great aunt being a woman?

     8. What disease caused the abnormal anatomical symptoms and led to the fracture?

     Underline one:  Osteoporosis  or  Paget's disease (osteitis deformans)

     9. What aspects of the above description help you distinguish these two possibilities? Explain.

     10. What notable anatomical features do the diseased locations have in common?

     11. Choose a therapy that is listed in your text and explain how it works to prevent this
     disease.

     [If modification of the diet is suggested, which of the basic four food groups would you recommend increasing consumption?]

Novel therapies

     The orthopedic surgeon suggests a new therapy for your great aunt's condition that relies upon the administration of the hormone calcitonin.  Your relatives want to understand how this hormone works.

     12. What effect does calcitonin have on the organ(s) affected by the disease?

     13. What effect does it have on the cells involved?

     14. What might its effects be on the body when given in excess of what the body normally produces?

     15. What dietary supplement might you recommend to accompany the calcitonin treatment?
     Why?
          
     One of your friends suggests treatment with parathyroid hormone (PTH) since it would elevate plasma calcium levels and would presumably enhance bone formation.

     16. Based on the actions of PTH do you think it will be effective in reversing the effects of the disease?  Explain.