osteomalacia, rickets, scurvy, HPT

Question 1

describe osteomalacia

Answer 1

altered bone quality
lack of calcium salts deposited
abnormally high ratio of osteoid to mineralized bone

Question 2

causes of osteomalacia

Answer 2

vitamin D metabolism

renal tubular phosphate loss (X-linked hypophosphatemia familial vitamin D resistant rickets, Fanconi’s syndrome)

Question 3

radiography of osteomalacia

Answer 3

non specific
osteopenia
coarsened trabeculation
looser zones
bone softening deformities
basilar invagination
acetabular protrusion

Question 4

what is the best diagnostic feature of osteomalacia

Answer 4

bone biopsy

Question 5

describe rickets

Answer 5

systemic disease of infant and young children
equivalent to osteomalacia in the adult
rare in western world
deficient in vitamin d, calcium or phosphate

Question 6

symptoms of rickets

Answer 6

decreased quantity of calcified osteoid
muscle tetany, irritabililty, weakness, delayed development, small stature, bone deformities and pain
soft tissue welling around the growth plates due to hypertrophied cartilage
calcium and phosphorus levels may be normal to low
ELEVATED ALKALINE PHOSPHATASE

Question 7

radiography of rickets

Answer 7

findings are most prominent in the fastest growing bones in the body
widened, bulky physeal plates and irregulatiry
splaying (cupping) of weakened bone at junction/metaphysis and physis
bowing deformities
“rachitic rosary” of chest due to cartilage overgrown and metaphyseal splaying at costochondral junction of ribs

Question 8

unique radiographic features of rickets

Answer 8

lack of provisional zone of calcification

paintbrush metaphysis

Question 9

describe scurvey

Answer 9

AKA barlow’s disease
long term deficiency of vitamin C
mostly involves infants fed pasteurized or boiled milk
occasionally elderly

Question 10

symptoms of scurvey

Answer 10

spontaneous hemorrhaging due to capillary fragility
cutaneous petechiae, bleeding gums, hematuria
joint swelling, irritability, pain and a tendancy to lie supine and motionless with thighs abducted

Question 11

scurvy can be mistaken for what?

Answer 11

child abuse

Question 12

lab findings and imaging findings for scurvy

Answer 12

low serum ascorbic acid levels
cartilage slow to proliferate but is mineralized
bone is osteopenic

Question 13

radiological features of scurvy

Answer 13

dense zone of provisional calcification
beak like metaphyseal outgrowths extended at right angles to shaft
radiodense sclerosis around epiphysis, radiolucent centrally
Trummerfeld’s zone (radiolucent band may be visible directly beneath zone of provisional calcification
corner sign (irregularity of metaphyseal margins)

Question 14

describe hyperparathyroidism

Answer 14

overactivity of the parathyroid gland

Question 15

primary HPT

Answer 15

parathyroid adenoma
MC type
MC cause of hypercalcemia
parathyroid adenoma (90%)
carcinoma, hyperplasia, ecroptic PTH producing tumors
elevated parathromone levels, hypercalcemia, hypophosphatemia

Question 16

secondary HPT

Answer 16

complication of chronic renal disease
persistant loss of calcium and phosphorus
stimulates PTH release

Question 17

tertiary HPT

Answer 17

seen in dialysis patients, parathyroid gland acts independent of serum calcium levels

Question 18

clinical features of HPT

Answer 18

30-50 years

women

Question 19

signs and symptoms of HPT

Answer 19

bone pain, fractures, weakness, lethargy, polydipsia, polyuria
hypercalcemia leads to muscle weakness, hypotonia
renal stones
pancreatitis
hypercalcemia in primary and tertiary
normal to low calcium in secondary
ALL have elevated alkaline phosphatase and elevated PTH

Question 20

radiography of HPT

Answer 20

osteopenia
subperiosteal resorption
distal tuft resorption
accentuated trabeculation
brown tumors
loss of cortial definition
soft tissue calcification

Question 21

what is the most definitive radiographic sign of HPT?

Answer 21

subperiosteal resorption

Question 22

subperiosteal resorption of HPT

Answer 22

especially at radial margins (middle and proximal phalanges of 2nd and 3rd digits)
outer cortical erosion may appear frayed or lace like
widened joint spaces and osteolysis, especially in the AC and SI joint

Question 23

axial skeletal problems of HPT

Answer 23

rugger jersey spine
subperiosteal resorption at SI joints
salt and pepper skull

Question 24

brown tumor

Answer 24

feature of HPT
geographic lytic lesion containing osteoclasts and mononuclear cells and fibroblasts with focal hemorrhages
central and slightly expansile
AKA osteoclastoma

Question 25

renal osteodystrophy

Answer 25

bone disorder occuring when the kidneys fail to maintain proper levels of calcium and phosphorus in the blood
affects patients on dialysis