Nutritional Metabolic and Endocrine Flashcards
what is the most common metabolic bone disorder
osteoporosis
what is defined as skeletal disease characterized by low bone mass and micoarchitectural deterioration of bone tissue with increase in bone fragility and susceptibility to fracture
osteoporosis
what is osteoporosis
what bones are affected
reduction in bone quantity - decreased bone density -
normal bone just not enough of it
axial skeleton and long bones
what is osteopenia
poverty of bone causes increased radiolucency of bone
what is regional osteoporosis
what is this due to
decrease bone density in region or segment of body - limb or portion of limb
immobilization after fracture
complex regional pain syndrome - reflex sympathetic dystrophy
transient osteoporosis of the hip is seen on what imaging
bone scan - hot
T1 - diffuse zone of low signal intensity - edema
T2- high signal - edema
what is localized osteoporosis
causes
focal loss of bone density affecting a small area of bone
inflammatory arthropathy
neoplasm
infection
what is senescent osteoporosis
senile or old age osteoporosis
what does bone mass start decreases
what percent is lost per year? cortical and trabecular
what percent is lost by age 65
at menopause, bone loss accelerates to what fold? what percent per year
> 35 years old
1% of bone mass lost per year of cortical bone
2% of bone mass lost per year of trabecular bone
20-40% of bone mass lost by age 65
menopause - 10 fold increase - 20 fold increase in lumbar spine - 6% lost per year
reduction in skeletal mass is gradual and is clinically evident in the __ decades of females life and __ decades of males
females - 5th and 6th decade
males - 6th and 7th decade
are men or women more affected by osteoporosis
at what age is the ratio equal
women MC 4:1
age 80 M=F
what are the risk factors and things than prevent osteoporosis
stay active and get exercise eat protein, calcium, vitamin c dont drink excessively take estrogen after menopause vitamin d
what are complications of osteoporosis
spinal cord compression fractures
increase thoracic kyphosis
fractures - femur, ribs, humerus, radius
incidence of __ fracture __ every __ years after the age of __ with osteoporosis
hip fracture
doubles
5 years
age 60
what are complications of bisphosphonates
example of drug
subtrochanteric femoral fracture - atypical stress fractures in femur diaphysis
alendronate
fosamax
actonel
what is the swedish study
2009 swedish study
study performed by Aspberger
incidence of mid femur stress fracture is 50x higher for patients on bisphosphonates
if osteoporotic patient presents with pain on coughing sneezing and straining what should you consider
acute compression fracture
progressive angular kyphotic deformity within a year of spinal compression fracture results in what
spinal stenosis
neurological abnormalities are __ with spinal compression fractures
infrequent
what is (percutaneous) vertebroplasty
results
complications
polymethylmethacrylate PMMA (acrylic bone cement) is injected into vertebral body to stabilize and strengthen collapsed vertebrae - outpatient
immediate and substantial results in perception of pain and function - strengthen and stabilize vertebrae
may have nerve root pain from leakage of injected material
20% of patients with osteoporosis compression fracture will experience what within 1 year
another fracture
what uses a balloon dilatation of vertebral body with subsequent instillation of polymethylmethacrylate
kyphoplasty
emphasis on balloon
what is a kyphoplasty procedure like
surgeon inserts catheter into vertebrae and then inserts and inflates a small balloon - this creates a cavity as it inflates - balloon is deflated and withdrawn from vertebrae - surgeon inserts needle into catheter to deliver cement into cavity - cement hardens and provides immediate stability
in weight bearing joints, preferential resorption of non essential supporting trabeculae occurs during bone loss with sparing of the most important trabeculae that are oriented ___
vertically - most important - they are spared in osteoporosis
what are some features of single photon absorptiometry
- high false negative rates - unreliable
- 2-5 mRad
- single photon emitted that is attentuated through bone - calcaneus or radius
- equal degree of association with vertebral osteoporosis
what are some features of dual photon absorptiometry
- photons emitted at 2 different levels
- applied to spine and proximal femur
- influenced by osteophytes, scoliosis, vascular calcifications, sclerosis
- 5-15 mRad
- low radiation dose to the patient
- high resolution images have been useful for evaluating vertebral fractures
ALSO CALLED DEXA!
dual energy xray absorptiometry
DEXA scores are reported as what
and what do these scores mean
T score and Z score
T score - comparison of bone density with that of a 30 year old of the same sex
Z score - comparison of bone density with that of an average person of same age and sex
what do the T scores of a DEXA scan indicate
T score
> -1 = normal
-1 to -2.5 = osteopenia
< -2.5 = osteoporosis
what do the Z scores of a DEXA scan indicate
< -2 = may indicate something other than the aging process is causing abnormal bone loss
what is a quantitative CT scan
MC used to assess the strength of vertebrae in assessment of fracture
measurements correlate with prevalence of fracture
200-250 mRAD!! alot of radiation
calibration with standard, dual photon beam passes through vertebral body, then compared to patient density with phantom density
what is used to assess bone mineral density as a diagnostic tool for osteoporosis and other related fractures
due to lower radiation dose and cost, DEXA scan remains the dominant screening tool
quantitative CT has increased with advent of new developments in CT technique
what are the advantages of quantitative CT over DEXA scan
- ability to separate cortical and trabecular bone
- provides true volumetric density in units of mg/cc
- no errions due to spinal degeneration cahanges or aortic calcification
- information on bone morphometry
what are the roentgen signs of osteoporosis
decrease bone density and mass - bone density approaches that of soft tissues
cortical thinning - pencil thin cortices, endosteal scalloping
altered trabecular pattern - trabecular resorption with accentuation of remaining trabeculae weigh bearing regions of bones, washed out appearance in severe stages
what is the generic term for bone loss
osteopenia
what percent of bone mass needs to occur before you see it on xray? appendicular skeleton? axial skeleton?
30-50% of bone mass needed to see on xray in appendicular skeleton
50-70% of bone mass loss needed to see on xray in axial skeleton
what are the features of osteoporosis in the spine
decreased bone density cortical thinning - end plates trabecular changes altered vertebral body shape increased kyphosis scoliosis due to compression fractures resorption of trabeculae
resorption of trabeculae due to osteoporosis will occur in what trabeculae first
what appearance does this give to the vertebral body
transverse vertebral body trabeculae resorbed first
pseudohemangioma appearance
osteoporosis can result in compression fractures of anterior and posterior portion of the vertebral body giving it the name of
vertebral plana or pancake vertebrae or crush
when you see pancake vertebrae or vertebral plana you must rule out what other conditions
how do we rule out
lymphoma
multiple myeloma
metastatic disease
lab studies
what is it called when there is loss of anterior vertebral body height
what is this due to
wedge vertebrae
may be due to trauma with normal bone mineralization or no trauma and poor bone mineralization
wedge vertebraes are most common where
mid thoracic
and
TL region
what shaped vertebrae is due to pressure of nucleus pulposus and weakened vertebral endplates
compare disc height to normal
biconcave vertebrae or hourglass vertebrae or fish vertebrae
normal disc height
what are schmorls nodes characteristics
small but can be large
painful
can trigger premature DDD process due to loss of nuclear pressure
there is strong evidence that pain carrying nerve fibers can grow inward, deep into the __ and __
this can cause pain known as __
middle annulus and nucleus pulposus
discogenic pain
what is our ddx if we see a vertebral body with GAS inside the body
metastatic disease myeloma radiation amyloidosis corticosteroid induced AVN
gas in a vertebral body will have what signal intensity on MRI
low signal
what are fractures that are oriented VERTICALLY seen as areas of osteolysis and adjacent areas of sclerosis
stress fractures
- sacrum and symphysis
insufficiency fractures are confirmed with what
MRI ?
bone scan
CT
what do sacral insufficiency fractures present as
what do rami fractures present as
sacral tenderness
pain in the low back, groin, and hip
some patients may be asymptomatic with both
sacral stress fracture has a characteristic ___ pattern that indicates insufficiency fracture
H pattern
or
Honda Sign
what do stress fractures look like in appendicular skeleton
how do they appear on MRI
cortical disruption along with a fine line of increased density - sclerotic bone forms after stress fracture
low signal intensity on T1
longitudinal stress fractures that are parallel with the bone appear how on MRI and CT
periosteal edema
marrow edema
transverse CT cuts are needed
in a running athlete with lower leg pain, the primary differential diagnosis includes
whats in your ddx if they are no distant runners
muscle and tendon injury
chronic compartment syndrome
shin splints
stress fracture
intermittent claudication
osteomyelitis
neoplasm
what is reflex sympathetic dystrophy syndrome
what is another term
complex regional pain syndrome
usually due to trauma
patient > 50
acute onset of painful regional osteoporosis
progressive pain, stiffness, swelling, atrophy, contracture
reflex sympathetic dystrophy syndrome or complex regional pain syndrome affects what areas MC
hand and shoulder
what causes the osteoporosis in complex regional pain syndrome
hyperemia of bone augments osteoclastic resorption of bone resulting in rapid progressive osteoporosis
what is the recover like for reflex sympathetic dystrophy syndrome
slow recovery
may never recover fully
residual dystrophy, contracture, joint stiffness
what are the joints and margins like in complex regional pain syndrome
joint spaces and margins are normal
what are the characteristics of transient osteoporosis of the hip
- left hip exclusively in females - severe osteoprosis of femoral head
- may have joint effusion
- unknown etiology
- 20-40 years old
- may be associated with pregnancy
- sudden onset of pain, antalgia, and limp
- full recovery in 3-12 months
what is another name for transient osteoporosis of the hip
why
transient bone marrow edema
presents with bone marrow edema in the femoral head and neck
what conditions cause transient bone marrow edema
transient osteoporosis of the hip AVN epiphyseal fractures arthropathies osteoid osteoma infection
what does transient osteoporosis of the hip look like on MRI
decreased signal on T1
increased signal on t2 (edema)
how does disuse and immobilization osteoporosis occur
immobilization inhibits osteoblastic activity in bone and accelerates osteoclastic activity of bone
when do xray changes occur in disuse and immobilization osteoporosis
does this process last forever
7-10 days
pronounced after 2-3 months
no, complete resolution of normal bone density after therapy
what are the 4 patterns of disuse osteoporosis
what is the most common pattern or form
uniform - all bone involved have similar degree of bone loss - MC form
spotty - localized circular lesions predominate especially in epiphyseal regions
bands - linear transverse subchondral or metaphyseal lucent zones
cortical - lamination or scalloping loss of definition in the outer and inner cortical margins
while steroids do decrease inflammation, they can also lead to steroid induced osteoporosis. how does this occur
steroids have the following affects:
decrease formation of new bone
increase breakdown of old bone
decrease absorption of calcium from food by the body
what is osteomalacia
what does it mean
what is it due to
altered quality of bone
means soft bone
lack of calcium deposited in osteoid due to altered calcium, phosphorous, or vitamin D metabolism
what are some conditions that can lead to osteomalacia
malabsorption syndrome
hypovitaminosis D
renal osteodystrophy
sprue - celiac disease
osteomalacia deformities of weight bearing bones are due to what
uncalcified osteoid located on surfaces of trabeculae and linings of haverians canals
what are the radiographic findings of osteomalacia
pseudofractures - also called looser or milkman lines
osteopenia
bone defomities
what do the pseudofractures appear like in osteomalacia on xray
fractures at right angles to the cortex
uncalcified osteoid
bilateral and symmetrical
after you see radiographic findings of osteomalacia, what is the next step
confirm with lab dx
what is rickets due to
due to deficiency of vitamin D, calcium, or phosphate
malabsorption
renal disorders
anticonvulsant drugs - dilantin
lack of sunshine
what is a systemic disease of young children and infants
what is the adult version
rickets
osteomalacia
when does rickets usually occur in children
6-12 months of age
what are the soft tissue abnormalities that occur in rickets
what are the gross general abnormalities that occur
soft tissue swelling around growth plates due to hypertrophied cartilage
rachitic rosary - unmineralized osteoid along anterior rib cage
what are characteristics of rickets
physis cartilage grow normally but fail to calcify
absent zone of provisional calcification
widening of growth plates due to accumulation of osteoid
irregular, frayed, cupped, metaphyseal margins
“paint brush” frayed zones of provisional calcification
bowing deformities, fractures, osteopenia, scoliosis, pseudofractures, abnormal bone length
what does scurvy do to bone
supresses osteoblastic activity
decreased production of collagen and osteoid
what people get scurvy
infants 8-14 months fed only boiled or pasteurized milk
or
long term deficieny of vitamin C
in scurvy, you need at least __ (amount of time) of avitaminosis C before symptoms and skeletal changes occur
4 months
what is the clinical hallmark of scurvy
spontaneous hemorrhages due to capillary fragility
what are the signs and radiographic findings of scurvy
generalized osteopenia due to inhibition of cell activity
white line of frankel - dense zone of provisional calcification
wimbergers rings - dense peripheral ring epiphysis
corner sign - infarction of epiphyseal/metaphyseal margins in irregularity affecting lateral and medial margins of zopc/white line of frankel
pelken spurs - spurs at metaphyseal margins extending perpendicular to cortex
scorburitc zone or trumerfeld zone - poor osteoid located along metaphyseal side of zopc which appears as radiolucent band
subperiosteal hemmorhage - blood elevates periosteum which may calcify when healing occurs
what area may collapse in scurvy
corner sign - may collapse or fracture with impaction
what is hyperparathyroidism due to
what does excessive PTH due
overactive parathyroid gland
initiates osteoclasts to resorption with fibrous tissue replacement causing osteitis fibrosa cystica (soft fragile bone)
what is tertiary hyperparathyroidism
state of excessive secretion of PTH after a long period of secondary PTH and resulting in high blood calcium levels
unregulated PTH
what are characteristics of hyperparathyroidism
brown tumors - accumulation of fibrous tissue produces cyst like destructive brown bone lesions
subperiosteal resorption - pathological - occurs along outer cortex at insertional points of ligaments and tendons
what are predictable locations for subperiosteal resorption in hyperparathyroidism
radial margins of middle and proximal phalanges - 2 and 3 digits
medial metaphysis of humerus and tibia
distal clavicles
trochanters and tuberosities
lacelike appearance of external bone
SI erosion
widening of pubic symphysis and AC joint
salt and pepper skull is characteristic of what diseases
hyperparathyroidism
salt and pepper - granular appearance of osteopenia
what do browns tumors look like in hyperparathyroidism
expansile
septated
mimics destructive lesion
fluid levels seen on MRI
rugger jersey sign is seen in what condition
hyperparathyroidism
seen in vertebrae
since blood calcium is increased in hyperparathyroidism, what can occur
calcification with tissues and organs
nephrocalcinosis - renal caliculi
chondrocalcinosis
sclerosis of monckenberg
monckenberg medial calcific sclerosis is a disease of what
medium sized muscular arteries
what are characteristics of monkenberg medial calcific sclerosis
- people over 50
- calcium deposits in tunica MEDIA of artery
- no intima involvment
- no vascular narrowing
- calcium may undergo calcificaiton
- seen on xray
what radiographic feature is pathognomonic for scurvy
trummerfeld zones
what are the clinical features of hypervitaminosis A
hepatosplenomegaly jaundice - yellow skin dermatitis pruritis alopecia osteopenia
what kind of periosteal reactions are noted on xray in hypervitaminosis A
solid periosteal reactions on shafts of long bones
femur, tibia, fibula, metatarsal, humerus, ulna, radius, metacarapals
what is the etiology of acromegaly
what does the etiology cause
secretory eosinophilic adenoma of anterior pituitary gland
produces intramembranous bone tissue growth and subcutaneous hypertrophy
what does secretory eosinophilic adenoma of anterior pituitary gland cause before the closure of growth plates? and after closure of growth plates?
before - gigantism
after - acromegaly
what are relevant features of acromegaly
heel pad thickness enlarged sella turcica widened mandible angle sinus enlargement prominent ungal tufts spade like ungal tufts premature DJD increase ADI due to cartilage overgrowth
why is heel pad thickness and ADI increased in acromegaly
what is the heel pad thicknesss in acromegaly
cartilage thickening
> 20 mm
what is lead poisoning also called
plumbism
what does plumbism cause
dense metaphyseal bands
aka lead lines
why is lead put into bone during lead poisoning
lead has higher affinity for bone than calcium so it replaces calcium
lead poisoning deposits lead into what part of the bone
during growing bone, lead is primarily deposited into the metaphysis
in children, lead poisoning affects what bones
why
metaphysis of distal femur, both ends of tibia, and distal radii
most rapidly growing bones in the body
what are clinical features of lead poisoning
pica - weird cravings of dirt and clay
