Ostoporosis Flashcards
What is osteoporosis
Defined as a BMD that lies 2,5 standard deviations below average
So a T score of < -2.5
What are the risk factors for osteoporosis
- Failures to achieve peak bone mass as an adult
- Bone loss later in life
- Genetic
- Idiopathic
What is primary osteoporosis
Aging process including the menopause
What is secondary osteoperosis
Secondary to pathological condition or medication
What age do people reach peak bone age
30
What decreases bone mass
Smoking, poor nutrition, inactivity, alcohol
What is primary osteoporosis type 1
•Post menopausal osteoporosis
• 15-20 years after menopause (55-70 years old)
• due to low oestrogen
• exclusively cancellous bone
• mainly affecting - vertebrae, distal radius
What is primary osteoporosis type 2
- Senile osteoporosis
-> 70 years old - directly related to the aging process
- both cancellous and cortical bone
- mainly affecting - hip, pelvis, long bones and vertebrae
What is secondary osteoporosis
Due to something else. Eg:
- endocrine diseases
- chronic diseases such as COPD or liver disease
- medications: corticosteroids, phenytoin
- nutritional deficiency: malnutrition, anorexia
what is involved in a fracture risk assessment?
Including which tools can be used?
Assesses 10-year probability of major osteoporotic fracture risk
Frax - fracture risk tool
QFracture tool
What are the indications for a fracture risk assessment?
~ all women over 65
~ all men over 75
~ those under these ages but with other risk factors
What does DEXA stand for?
Dual-energy X-ray absorptiometry scan
DEXA scan info
Very low dose
- most common L-spine and femur
Forearm can be used if these are not available
What is a T-score?
The T-score shows how much your bone mass differs from the bone mass of an average 30 year old adult.
What is a Z-score?
The Z-score compares your bone density with that of people your own age,size and sex.
How is the score from the DEXA scan measured?
As a standard deviation from the mean
How often is a DEXA scan repeated?
2 - 5 years depending on individual case
What are the Advantages of CT looking at bone density?
Highly specific
Better accuracy
Enter in axial skeleton assessment (multi detector)
What are the disadvantages of CT for looking at Bone density?
More expensive
More radiation
What are the advantages of DEXA scanning?
- cheap
- widely used
- high sensitivity
What are the disadvantages of DEXA scanning?
- operator dependant
-Less accurate - Low specificity
What is osteopenia?
Bone density has begun to dwindle but is not yet considered dangerous
What is the T - value for osteopenia?
Between -1 and -2 SD
What is osteoporosis?
Bone density levels become critical and frequent fractures are likely.
What is the T-value for osteoporosis?
T-value < -2 standard deviations
How do osteoporotic bones show under X-ray ?
- Increased radiolucency
- Cortical thinning
- Altered trabecular pattern
What is Osteomalacia and rickets?
Osteomalacia = soft bones
Decreased mineralisation of newly formed bone matrix
Rickets is the same condition but in children
Both increase the risk of fractures and bone deformities.
What are the preventative measures for loss of bone density?
+ strength training exercises
+ diet (high calcium intake)
+ vitamin D supplements
+ medications (such as bisphosphonates)
+ stopping medications causing osteoporosis
+ bone protection for people on long-term steroids
+ reducing alcohol intake and smoking
