Osteoporosis Flashcards
Role of osteoblasts
Fill in bone cavity
Release cytokines to attract osteoclasts
Build Bone
Role of osteoclasts
Releases proteases which dissolves bone
Clears damaged bone
Release chemicals that attract osteoblasts
What does T-score show? E.G: a value more that 2.5 and a value of 1?
No. of standard deviations away from mean peak Bone Mass Density
2.5 = osteoporosis
1= normal
Primary Osteoporosis
Diagnosed when patient has no other osteoporosis causing disorders
E.g: Postmenopausal women
Secondary Osteoporosis
IBD
Endocrine illnesses
Drug therapies
Rheumatoid Arthritis
Most common cause of secondary Osteoporosis?
Corticosteroids
Decrease osteoblast activity and life span
Decrease calcium absorption
Suppresses sex hormone production
What is a fragility fracture?
Fracture from a force that wouldn’t usually cause a fracture: falling from standing etc.
what is kyphosis?
Deformed spine- forward curvature
Groups of people who need prophylaxis of osteoporosis
Anyone with fragility fracture
women over 70yrs
Post menopausal women
men over 50 years if on high dose steroids
What is FRAX score
To predict 10 yr risk of osteoporotic fracture
Treatment for Low Risk Osteoporosis
Lifestyle and calcium/ vitamin D
Treatment for Medium Risk Osteoporosis
Assess BMD with DEXA scan
Treatment for High Risk Osteoporosis
Start treatment without BMD assessment
Lifestyle changes for osteoporosis
Low impact exercise
Muscle training for hip, spine or wrist
Avoid smoking/ drinking
Eat calcium rich foods
Exposure to sun
Dosage of calcium and vit. D
1000mg calcium
800 units vit. D
What medications increase risk of falls
Anti-hypertensives
Sedatives
Diuretics
Vision problems
Drug treatments for osteoporosis
1st line: Bisphosphonates
2nd line: Denosumab, raloxifene, HRT / also with Calcium and Vitamin D
Example of bisphosphonates
Alendronate
Risedronate
Counselling points for bisposphonates
Empty stomach
30mins before food
With water
Remain upright for 30mins
Report any oesophageal irritation
Vitamin D deficiency (~25nmol/L)
Loading dose ~300k units over 6-10 weeks
Maintenance dose: 800-2000 units daily
Bisphosphonates Pharmacology
Alendronic acid- binds to calcium in bone
Released as bone is reabsorbed
Main action is osteoclasts
Raloxifene Pharmacology
Selective oestrogen receptor modulator
Stimulates osteoblast activity
Denosumab Pharmacology
Monoclonal antibody to RANKL
Inhibits binding of RANKL to RANK
Calcitonin Pharmacology
Antagonistic to PTH
increases conc. of calcium in urine
Decreases conc. of calcium
Teriparatide Pharmacology
Active fragment of PTH
Acts at PTH receptors
Opposite effects to PTH
Strontium Pharmacology
Increases sensitivity of calcium sensing receptor in parathyroid cells
Decreases PTH secretion
