Osteoporosis Flashcards
What is osteoporosis?
What is the outcome if trabecular or cortical bone is involved?
Osteoporosis = reduced bone mass + increased bone fragility and risk of fracture.
If trabecular bone affected = crush fractures of vertebrae hence the dowager’s hump in ladies
If cortical bone affected = long bone fractures i.e. femoral neck (big cause of death & orthopaedic expense)
Who does osteoporosis affect?
> 50 years old
Women > Men
=> Women lose trabecular bone with age. 80% hip fractures occur in women
=> Men have reduced bone formation but the numbers of trabeculae are stable => less risk of fractures
There are two types of osteoporosis:
i. Primary osteoporosis
ii. Secondary osteoporosis
What are the causes of each?
Primary osteoporosis due to age
Secondary osteoporosis due to a condition / drugs
Osteoporosis is a major cause of morbidity and mortality in the elderly.
What are the risk factors for osteoporosis?
SHATTERED pneumonic
Steroid use >5mg/d of prednisolone
Hyperthyroidism, hyperparathyroidism, hypercalcaemia
Alcohol & tobacco use
Thin BMI <18.5
Testosterone low e.g. antiandrogen prostate cancer treatment
Early menopause
Renal or liver failure
Erosive/inflammatory bone disease e.g. myeloma or RA
Dietary low calcium / malabsorption ; Diabetes type 1
What are age independent risk factors for primary osteoporosis?
- Parental hx
- Alcohol >4units daily
- RA
- BMI <18.5
- Prolonged immobility
- Untreated menopause
What is the investigation for osteoporosis?
X-ray (low sensitivity / specificity)
DEXA
What is the investigation for osteoporosis?
X-ray (low sensitivity / specificity)
DEXA - measures bone density
=> usually of the lumbar spine and proximal femur
=> gold standard in diagnosis of osteoporosis
Bloods: calcium, phosphate and ALP normal
What are some indications for DEXA scan?
=> previous low trauma fractures for women >65yrs with one or more risk factor for osteoporosis / 2 or more risk factor if younger
=> prior to long term prednisolone
*bc steroids cause osteoporosis by promoting osteoclast bone resorption, reduced calcium absorption in the gut, reduced muscle mass
=> bone disorders i.e. myeloma, parathyroid disorders
What are some lifestyle advice to help prevent / delay osteoporosis?
- Stop smoking
- Reduce alcohol
- Weight bearing exercise may increase bone density
- Balance exercises i.e. tai-chi reduce risk of falls
- Calcium and vitamin D rich diet + supplements
- Home-based fall prevention programme with visual assessment + home visit
What is the pharmacological management of osteoporosis?
- Bisphosphonates: 1st line
=> e.g. Alendronic acid
=> Inhibit osteoclast activity
=> also used for prevention in long term steroid use
=> SE: photosensitivity, GI upset, oesophageal ulcers - Calcium & vitamin D: used in deficiency ; rarely used for prophylaxis (lacking evidence)
- HRT in post-menopausal women
=> can help prevent osteoporosis post menopause
