Osteoperosis Flashcards
What are osteoclasts and what do they do ?
Bone degrading cells that initiate bone remodelling. While degrading bone they release proteases which go on to dissolve more bone mineral matrix and collagen.
What are osteoblasts and what do they do ?
Bone forming cells that…
* Fill in bone cavity with bone matrix.
* Release cytokines to attract osteoclasts.
What are the genetic risk factors of osteoperosis ?
Genetic factors
* Direct family with osteoperosis
* Vitamin D receptor gene
* Oestrogen receptor gene
* Interleukin-6 gene
What are the environmental risk factors of osteoperosis ?
Environmental:
* Low calcium intake/absorption
* Low vitamin D intake
* Physical inactivity
* Alcohol
* Smoking
* Thin body type
What is Osteoperosis ?
A common metabolic bone disease. It is the severe reduction in bone density. It can come in the form of primary or secondary osteoperosis.
How is osteoperosis measured and diagnosed?
It is measured and daignosed via a T-score test. T-score results…
* Healthy: > -1
* Osteopenia: Between -1 and -2.5
* Osteoperosis: < -2.5
What is osteopenia ?
Osteopenia is the clinical term for a lower than average bone density but not low enough to be classed as osteoperosis.
Can osteoperosis be detected ?
X-ray
* Cannot detect bone loss until 30% is lost [TOO LATE]
* Not sufficient in diagnosing osteopenia or osteoperosis.
Dual Energy X-ray Absoption (DEXA)
* Expensive
* Accurately and reproducibly measures bone mass density.
What is primary osteoperosis ?
Primary osteoperosis is when there is no other disorder present (that is known to cause OP). Primary osteoperosis is almost always related to age (e.g. postmenopausal osteoperosis)
What is secondary osteoperosis ?
Osteoperosis that is either drug-induced (steroids) or by a known underlying disorder/disease such as…
* Anorexia nervosa (gaslighting yourself to believing you are fat)
* IBD (inflammatory bowel disease)
* Type 1 DM
* Cushing’s syndrome
What is drug-induced osteoperosis ?
Prescribed steroid use can result in osteoperosis as it…
* Decreases osteoblast activity
* Decrease calcium absorption
* Increase renal calcium loss
* Supress sex hormone production (oestrogen is important for bone structure)
What are the symptoms of osteoperosis ?
Symptoms include:
* Fragility fractures
* Kyphosis
What is Kyphosis ?
It is the gradual collapse of the spine resulting in a forward curviture which also leads to height loss.
What are fragility fractures ?
Fractures that occur upon a mechanical force that would not ordinarily cause a fracture. This is seen in patients with osteoperosis.
Most common fractures:
* Vertebra (spine)
* Distal radius (wrist)
* Neck of femur (hip)
People of risk to Osteoperosis ?
- Postmenopausal women
- BMI < 19 kg/m2
- Untreated premature menopause
- Alcohol & smoking
- Family history of maternal hip fracture before the age of 75.
- Disease {hyperthyroidism, coliac disease, rheumatoid arthritis, inflammatory bowel disease}
- Glucocorticoid therapy {prednisolone, hydrocortisone etc.}
*
What medication can cause osteoperosis ?
Glucocorticoids long-term therapy (few months) leads to…
* Increased risk of spine fracture
* Increased risk of hip fracture
* Massive rate of loss of bone mass density
What is FRAX ?
Fracture risk assessment tool
* An online tool that predicts a persons 10-year risk of developing a major osteoperotic fracture.
* It dictates the next steps in assessing or diagnosing for osteoperosis.
