Osteoporosis

Question 1

If crush fractures > long bone fractures in osteoporosis - which part of the bone is affected? vice versa?

Answer 1

If trabecular bone is aff ected, crush fractures of vertebrae are common (hence the ‘littleness’ of little old ladies and their dowager’s hump); if cortical bone is affected, long bone fractures are more likely, eg femoral neck:

Question 2

Risk factors for osteoporosis?

Answer 2

parental history
alcohol >4 units daily
rheumatoid arthritis, BMI <19
prolonged immobility
untreated menopause

Steroid use
Hyperthyroidism/ hyperparathyroidism/ hypercalciuria
Alcohol and tobacco use
Thin (BMI <18.5)
Testosterone low ((eg anti androgen ca prostate Tx).
Early Menopause
Renal or liver failure
Erosive/inflammatory bone disease (eg. myeloma or rheumatoid arthritis)
Dietary calcium reduced or malabsorption; diabetes mellitus type 1

Question 3

Osteoporosis investigations?

Answer 3

DEXA scan

Urea & Electrolytes, Calcium, Phosphate, Alkaline Phosphatase, Thyroid Function.
Consider 25-OH Vitamin D if clinical evidence of osteomalacia.

Question 4

Indications for a DEXA scan? When is DEXA not needed

Answer 4

NICE suggests DEXA if previous low-trauma fracture or for women ≥ 65yrs with one or more risk factors for osteoporosis, or younger if two or more.

prior to giving long-term prednisolone (eg >3 months at >5mg/d)

Men or women with osteopenia if low-trauma, non-vertebral fracture.

Bone and bone-remodelling disorders (eg parathyroid disorders, myeloma, HIV, esp. if on protease inhibitors).

DEXA is not needed pre-treatment for women over 75yrs if previous low-trauma
fracture
or ≥ 2 present of rheumatoid arthritis, alcohol excess, or positive family history.

Question 5

How do steroids cause osteoporosis?

Answer 5

by promoting osteoclast bone resorption, reducing muscle mass, and reducing Ca2+
absorption from the gut.

Question 6

Risk assessment tool for osteoporotic fracture?

Answer 6

FRAX, which is a WHO risk assessment

tool for estimating 10-yr risk of osteoporotic fracture in untreated patients

Question 7

Lifestyle measure for osteoporosis Mx?

Answer 7

Advise adequate intake of calcium, vit D and protein, weight bearing physical exercise, smoking cessation, minimize excess alcohol intake

Question 8

Pharmacological Mx of osteoporosis?

Answer 8

Bisophonates: 1st line: Alendronic acid - If intolerant, try etidronate or risedronate. -

Question 9

What medication is used for pharmacological Mx of osteoporosis?

Answer 9

Bisphosphonates
Calcium and vit D
strontium ranelate
HRT
Raloxifene
Teriparatide
Calcitonin
Testosterone
Denosumab

Question 10

How to take bisphosphonates? examples? SEs? Ix before commencing? CI? Alternative to oral bisphos?

Answer 10

Bisophonates: 1st line: Alendronic acid - If intolerant, try etidronate or risedronate.
Tell patient to swallow pills with 240ml water while remaining upright for >30min and wait 30min before eating or other drugs.

SE: photosensitivity
oesophageal reactions: oesophagitis, oesophageal ulcers
increased risk of atypical stress fractures of the proximal femoral shaft in patients taking alendronate
acute phase response: fever, myalgia and arthralgia may occur following administration
hypocalcaemia: due to reduced calcium efflux from bone. Usually clinically unimportant

Calcium, Vit D, renal function (eGFR>30)

CrCl>35 - if less use raloxefine

CI: Achalasia, strictures, ulcers - in which case

IV Zoledronate once a year (30min infusion) - optimise calcium and vit D - check teetch and post infusion Ca2+

Question 11

Strontium ranelate SE? Use?

Answer 11

increased risk of CV events, thromboembolic events and serious skin reactions
should only be used in those with severe intolerance of other agents and without cardiovascular disease

Question 12

HRT use? SE? Alternative?

Answer 12

no longer recommended for primary or secondary prevention of osteoporosis unless the woman is suffering from vasomotor symptoms
Increased risk of breast ca. and CV disease

raloxifene

Question 13

Raloxifene MOA?

Answer 13

selective oestrogen receptor modulator (SERM) that acts similarly to
HRT, but with reduced breast cancer risk.

Question 14

Teriparatide use? SE?

Answer 14

(recombinant PTH)

useful in those who suffer further fractures despite treatment with other agents. There is a potential increased risk of renal malignancy

Question 15

Calcitonin use?

Answer 15

may reduce pain after a vertebral fracture

Question 16

Denosumab MOA? Use? SEs? Admin?

Answer 16

a monoclonal Ab to RANK ligand

Inhibits ossteoclast formation, reduces bone resorption and increases BMD

Use if intolerant to other therapies eg. IV zoledronate + in those with impaired renal function

SEs: Skin infections, ONJ, stress fractures

Admin: Subcut once every 6 months - cannot be stopped abruptly –> rapid drop in BMD –> vertebral fracture

Question 17

Common bone problems in elderly?

Answer 17

Osteoporosis and vit D deficiency. Also Paget’s disease of the bone, osteomalacia (clinically evident vitamin D deficiency), and Hyperparathyroidism.

o Bone pain or hypercalcaemia raises the suspicion of fractures, bony metastases or primary malignancy of the bone.

Question 18

Phases of bone loss in women?

Answer 18

1. occurs predominantly in trabecular bone and starting at menopause – menopause related bone loss
2. After 4-8 years, the second phase exhibits a persistent, slower loss of both trabecular and cortical bone, and is mainly attributed to reduced bone formation - This is age related bone loss, which is the only phase that also happens in men.

Question 19

Medications that contribute to bone loss?

Answer 19

	SSRIs
	antiepileptics
	proton pump inhibitors
	glitazones
	long term heparin therapy
	aromatase inhibitors e.g. anastrozole
	Glucocorticoids
Hormonal treatment (tamoxifen)

Question 20

Define fragility fracture? Common fractures?

Answer 20

Fracture from falling from standing height, or lower at walking speed or slower
Vertebrae, proximal femur, wrist (distal radius, pelvis, ribs

Question 21

Define alcohol excess for men and women

Answer 21

Alcohol excess for osteoporosis = >14 units in women, >21 units per week in men