Osteoporosis Flashcards
(29 cards)
What structural bone changes occur in osteoporosis?
Decreased osteon size, trabecular thinning, enlargement of Haversian and marrow spaces.
What is Type 1 osteoporosis?
Post-menopausal osteoporosis affecting cancellous bone, common fractures: vertebrae and distal radius; related to estrogen loss; F:M ratio = 6:1.`
What is Type 2 osteoporosis?
Age-related osteoporosis (>75 years), affects both cancellous and cortical bone; common fractures: hip and pelvis; F:M = 2:1.
What is disuse osteoporosis?
Osteoporosis caused by prolonged immobilisation, especially in neurological or muscle diseases.
How prevalent is osteoporosis in the UK?
Affects about 3 million people; 1 in 3 women and 1 in 12 men.
What is a fragility fracture?
A fracture caused by low-energy trauma, such as a fall from standing height.
What is the annual cost of fragility fractures to the NHS?
Over £4.4 billion.
What are the morbidity stats associated with hip fractures?
20–30% fatality, only 30% fully recover, 50% become permanently disabled.
What are the common fracture sites in osteoporosis?
Proximal humerus, distal radius, spine, femoral neck, vertebral body.
Name at least three risk factors that reduce bone strength.
Hormonal imbalance, poor nutrition, lack of exercise, lifestyle factors (e.g., smoking, alcohol).
How does osteoporosis prevalence vary by ethnicity?
Lower in Black Americans; fracture rates 4.7x higher in White women in the UK; Latin Americans have higher risk in the US; Chinese women have lower BMD but also lower fracture rates.
How does GAHT (gender-affirming hormone therapy) affect BMD in transgender patients?
May protect BMD in both trans women and men; trans women have lower BMD pre-GAHT.
What lifestyle factors increase osteoporosis risk?
Smoking, excess alcohol, sedentary lifestyle, prolonged immobilisation
Name three medical conditions that increase osteoporosis risk.
Diabetes, IBD, epilepsy, HIV, CKD, chronic liver disease, endocrine disorders.
List three drugs associated with increased osteoporosis risk.
Glucocorticoids, antiepileptics, antidepressants, aromatase inhibitors, PPIs, GnRH agonists, thiazolidinediones.
How does a previous fragility fracture impact future fracture risk?
Previous wrist fracture doubles risk of hip fracture and triples risk of vertebral fracture.
What is the primary imaging method for osteoporosis diagnosis?
DEXA scan (Dual-energy X-ray absorptiometry).
What do T and Z scores represent in a DEXA scan?
T score compares to young adult peak bone mass; Z score compares to age/sex/size-matched controls.
What are bone turnover markers and their types?
Biochemical tests used to assess bone formation (e.g. ALP) or resorption (e.g. CTX).
Name two investigations to rule out secondary causes of osteoporosis.
Thyroid function tests; testosterone and gonadotrophin levels (in men).
What is the mechanism of action of bisphosphonates?
Antiresorptive: they disrupt osteoclast activity.
What are side effects of bisphosphonates?
GI upset, oesophagitis, mandibular necrosis, uveitis, atypical femur fractures.
What is Denosumab and its mechanism?
A monoclonal antibody against RANKL that prevents osteoclast formation and lifespan.
What is Romosozumab and how does it act?
A monoclonal antibody against SOST; both antiresorptive and anabolic by promoting osteoblasts and inhibiting osteoclasts.
