biochemistry Flashcards
what is osteochondritis dissecans?
inflammation of bone and cartilage
who does osteochondritis dissecans usually occur in and why?
young adults
increased physical activity and body weight
what does recurrent impact trauma lead to?
bleeding + oedema in bone -> capillary compression -> bone necrosis -> bone fragmentation
how does osteochondritis dissecans usually present?
poorly localised pain
effusion
locking
what is the management of osteochondritis dissecans?
pinning or removal or unstable fragments
what is avascular necrosis?
ischaemic necrosis of bone (common at hip)
what is avascular necrosis due to?
fractures disrupting blood supply
alcohol
steroid abuse
SLE
how can necrosis lead to OA?
necrosis -> patchy sclerosis -> subchondral collapse + irregular articular surface -> OA
what is osteoporosis?
fragile bone due to reduced bone mineral density -> fractures
what are the risk factors of osteoporosis?
lack of exercise
poor diet
lack of sunlight
when does osteoporosis usually occur?
post-menopause
old age
steroid/alcohol use
malnutrition
what is the diagnostic test for osteoporosis?
DEXA scan
what is the management of osteoporosis?
prevent fractures - lifestyle + strengthen + vitD/Ca2+ supplements
what is the treatment for slow deteriorating osteoporosis?
bisphosphonates -> reduce osteoclast activity
teriparatide -> synthetic PTH -> stimulates osteoclasts
what is osteomalacia and Rickett’s?
abnormal softening of bone due to deficient mineralisation
what is osteomalacia and Rickett’s due to?
insufficient calcium absorption
less dietary calcium/vitD deficiency/less phosphate (inc. renal losses)
how does osteomalacia and Rickett’s present?
bone pain
soft bone deformities fractures
hypocalcaemia signs
what is a physical sign of Rickett’s?
bowing of the legs
what will be seen in investigations in osteomalacia and Rickett’s?
low calcium
low serum phosphate
high serum ALP
what is the management of osteomalacia and Rickett’s?
vitD + calcium + phosphate supplementation
what is Paget’s disease?
thickened brittle and misshapen bones
what causes Paget’s disease?
osteoclasts/osteoblasts speeding up
what are the stages of Paget’s disease?
lytic phase -> mixed -> sclerotic phase
who does Paget’s disease usually affect and where?
older patients
pelvis
spine
skull
femur
how does Paget’s disease usually present?
constant dull bone pain
what will be seen in investigations?
raised ALP
normal calcium + phosphorus
what investigation is used in Paget’s disease?
imaging
what is the management of Paget’s disease?
bisphosphonates (calcitonin if excessive)
