Bone Disorders Flashcards
what are the three main types of bone cells?
osteoclasts
osteoblasts
osteocytes
what do osteoclasts do?
responsible for bone resorption
what do osteoblasts do?
responsible for bone formation
what is the primary cell of mature bone?
osteocytes
name five factors that affect the ability to achieve peak bone mass
genetics being underweight sex hormones diet exercise
name six factors that increase the rate of physiological bone loss
sex hormone deficiency body weight diet immobility disease drugs
what two types of drugs increase rate of physiological bone loss?
glucocorticoids
aromatase inhibitors
when is peak bone mass usually attained?
around 30
when does age related bone loss start?
around 50
what is it called when the bone mass stays stable?
consolidation
what causes a steep decline in bone mass in women?
menopause
who has a higher bone mass throughout life - males or females?
males
what is the major determinant of bone loss in women after the menopause?
oestrogen deficiency
what are four common fracture sites in osteoporosis?
neck of femur
vertebral body
distal radius
humeral neck
name two tools that can be used to assess fracture risk in osteoporosis?
QFracture
FRAX
name some non modifiable risks for osteoporotic fractures
age gender previous fractures family history early menopause
name some modifiable risks for osteoporotic fractures
bone mineral density alcohol weight smoking inactivity
who should be assessed for osteoporosis?
> 50 with any risk factors
< 50 with very strong risk factors
what are the very strong risk factors for osteoporosis?
early menopause
glucorticoids
how should be referred for a DEXA scan?
patients with 10 year risk for osteoporotic fractures >10%
what is the most common method for measuring BMD?
DEXA scan
what two areas are scanned in a DEXA scan?
L1-L4
non dominant hip
what is the Z score in a DEXA scan?
their BMD compared to the peak in a young population - assesses whether loss is age appropriate
what is the T score in a DEXA scan?
BMD compared to their own age group
what is normal on a DEXA scan?
BMD within 1SD of the young adult reference mean
what is osteopenia on a DEXA scan?
BMD >1SD below the young adult mean
what is osteoporosis on a DEXA scan?
BMD >2.5SD below the young adult mean
what is severe osteoporosis on a DEXA scan?
BMD >2.5SD from young adult mean alongside a fracture
what lifestyle advice is given for osteoporosis?
strength training
low impact exercise
alcohol and smoking avoidance
fall prevention - OT
what mineral do people with osteoporosis need to eat more than average of?
calcium
eat 1000mg a day
what is the first line drug management of osteoporosis?
calcium + vit D supplements
bisphosphonates
when can calcium supplements not be taken?
within 2 hours of bisphosphonates
how do bisphosphonates work?
anti resorptive agents - preventing bone loss
name two bisphosphonates
alendronate
risedronate
what are the complications of long term use of bisphosphonates?
osteonecrosis of the jaw
oesophageal carcinoma
atypical fractures
what are the possible second line drugs for osteoporosis?
zoledronic acid
denosumab
teriparatide
romosozumab
what should be considered in patients with early menopause tor reduce fracture risk?
HRT
what is the pathophysiology of Paget’s disease of bone?
initially normal bone resorption followed by increased bone formation
= results in abnormal structure with reduced strength
what is it called when Paget’s disease of bone affects one site?
monostotic
what is it called when Paget’s disease of bone affects more than one site?
polyostotic
where does Paget’s disease of bone usually affect?
long bones
pelvis
lumbar spine
skull
how does Paget’s disease of bone present?
bone pain
deformity
deafness
compression neuropathies
what is a rare complication of Paget’s disease of bone?
osteosarcoma
how is Paget’s disease of bone diagnosed?
x-ray
isotope bone scan
bloods
what is seen on bloods in Paget’s disease of bone?
raised ALP
how is Paget’s disease of bone managed?
analgesia
bisphosphonates
what is osteogenesis imperfecta?
group of genetic disorder affecting bone
what can osteogenesis imperfecta be associated with?
blue sclerae
dentinogenesis imperfecta
how is osteogenesis imperfecta managed?
fracture fixation
surgery for deformities
bisphosphonates
