Osteoporosis

Question 1

what is osteoporosis (3)

Answer 1

defect of bone characterised by reduced bone mineral density and increased porosity (i.e. the bone is of normal quality, there is just not enough of it).

leads to fragility of the bone and increased fracture risk with fractures occurring after little or no trauma.

bone mineral density less than 2.5 standard deviations below the mean peak value of young adults of the same race and sex.

Question 2

what is osteopenia

Answer 2

an intermediate stage where bone mineral density is between 1 to 2.5 standard deviations below mean peak value.

Question 3

bone mineral density

Answer 3

Loss of bone mineral density is for the most part a physiologic phenomenon which starts at around the age of 30 with a very gradual slowdown in osteoblastic activity.

Females tend to lose more bone mineral density after the menopause due to an increase in osteoclastic bone resorption with the loss of protective effects of oestrogen.

Question 4

Type 1 (4)

Answer 4

Post‐Menopausal Osteoporosis with an exacerbated loss of bone in the post‐menopausal period.

Early menopaiuse may have an influence whilst familial and environmental factors (white Caucasians at particular risk) may play a role.

Further risk factors include smoking, alcohol abuse, lack of exercise and poor diet.

Colles fractures and vertebral insufficiency fractures tend to occur in this group.

Question 5

Type 2 (3)

Answer 5

old age with a greater decline in bone mineral density than expected.

Risk factors are similar with the added risks of chronic disease, inactivity and reduced sunlight exposure (Vitamin D).

Femoral neck fractures and vertebral fractures predominate in this group.

Question 6

Other conditions can cause osteoporosis (5)

Answer 6

-corticosteroid use
-alcohol abuse
-malnutrition,
-chronic disease (CKD, malignancy, Rheumatoid arthritis)
-endocrine disorders (Cushing’s, Hyperthyroidism, Hyperparathyroidism).

Question 7

diagnosis (2)

Answer 7

DEXA scanning to provide a measure of bone mineral density, and values are compared with standard peak values for race and sex as well as age standardized values.

Serum calcium and phosphate are normal.

Question 8

treatment - non pharma (3)

Answer 8

no treatments can increase bone mineral density.

treatments aim to slow any further deterioration and hopefully decrease the risk of subsequent fracture.

exercise, good diet and healthy levels of sunlight exposure

Question 9

treatment- pharma (5)

Answer 9

prevent fragility fractures include

-calcium and vitamin D supplements (if dietary intake is poor)

-bisphosphonates (alendronate, risedronate, etidronate) which reduce osteoclastic resorption,

-Desunomab (a monoclonal antibody which reduces osteoclast activity)

-strontium (which increases osteoblast replication and reduces resorption).

-Zoledronic acid is a once yearly intravenous bisphosphonate but is substantially more expensive than oral forms.