Bone disease Part 3

Question 1

what are the 4 stages that happen when there is low levels of calcium in the blood

Answer 1

1. Increased PTH secretion
2. Osteoclasts stimulated to resorb bone
3. Calcium is released into plasma
4. Feedback to reduce PTH secretion

Question 2

2. What is hyperparathyroidism

Answer 2

Increased osteoclast activity as a result of increased levels of PTH with Destruction of cortical and trabecular bone and Inadequate osteoblast compensation

Question 3

4. What 3 things that hyperparathyroidism make bones more susceptible to?

Answer 3

• Fractures
• Bone deformation
• Joint issues

Question 4

5. What can reverse the bone changes in hyperparathyroidism

Answer 4

Reduction PTH levels

Question 5

6. What are the two types of hyperparathyroidism and explain them

Answer 5

• Primary: Tumour with elevated serum calcium + focal osteolytic lesions
• Secondary: low serum calcium caused by renal disease (excessive loss via abnormal kidneys) causes hyperplasia of parathyroid glands (kidney disease causes osteomalacia)

Question 6

7. What is Paget’s disease

Answer 6

Overactive osteoclasts destroy bone and result in osteoblasts laying down bone rapidly - it is immature woven bone.

Bone mass is increased but it is weak

Question 7

8. What percentage of Europe and US population is affected by Paget’s disease

Answer 7

2.5% of population In Europe and US

Question 8

9. Why is metabolic demand high in Paget’s disease

Answer 8

high due to excessive bone turnover

Question 9

10. What is the cause of bone pain in Paget’s disease

Answer 9

consequences of nerve impingement (headaches, back pain

Question 10

11. Where is 80% of pain in Paget’s disease found?

Answer 10

80% in axial skeleton/proximal femur

Question 11

12. Although there is no known cause of Paget’s disease, what are 2 thought reasons of Paget’s disease

Answer 11

• Viral infection of osteoclasts (paramyxovirus)
• hypersensitivity of osteoclasts