Brs - Musculoskeletal System

Front 1

difference between becker and duchenne muscular dystrophy

Back 1

dmd invariably forms a stop codon with a frame-shift mutation in the dystrophin protein
bmd has segmental deletions that are less severe, and there is no coding frameshift

Front 2

which types of muscular dystrophy has an autosomal dominant inheritance?

Back 2

fascioscapulohumeral muscular dystrophy
myotonic dystrophy

Front 3

which type of muscular dystrophy has autosomal recessive inheritance?

Back 3

limb-girdle dystrophy

Front 4

describe presentation of fascioscapulohumeral muscular dystrophy?

Back 4

slowly progressive
non-disabling course
almost-normal life expectancy
sequentially involves muscles in face, scapula, and humerus

Front 5

difference between hypertrophy and pseudohypertrophy?

Back 5

hypertrophy begins first where there is compensation by distal muscles of legs (calves)
pseudohypertrophy has the appearance of being enlarged, but has increased fibrous tissue and adipose tissue

Front 6

what are the 3 types of congenital myopathies?

Back 6

central core disease
nemaline disease
mitochondrial myopathy

Front 7

what are hte histological differences between the 3 types of congenital myopathies

Back 7

central core disease: loss of mitochondria and other organelles in center portion of type 1 muscles

nemaline disease: small rod shaped granules and tangles in type 1 fibers

mitochondrial myopathies: ragged red appearance of muscle fibers

Front 8

clinical presentation of central core disease

Back 8

muscle weakness and hypotonia, although affected infants can become ambulatory

Front 9

clinical presentation of nemaline myopathy

Back 9

varies from mild, non-progressive dz to severe weakness ending in death from respiratory failure

Front 10

clinical presentation of mitochondrial myopathy

Back 10

varies

Front 11

example of mitochondrial myopathy

Back 11

kearns-sayre syndrome -->
opthralmoplegia, pigmentary retinopathy, heart block, cerebelar ataxia

Front 12

pathogenesis of MG

Back 12

autoantibodies to ACh receptors

Front 13

clinical presentation of MG

Back 13

weakness intensified with muscle use, with recovery on rest
effort associated weakness of all muscles (incl extraoc)
ptosis and diplopia common presenting features
difficulty chewing, speaking, swallowing

Front 14

what is MG associatd with?

Back 14

tumors of thymus
thymic hyperplasia

Front 15

Lambert-eaton syndrome

Back 15

paraneoplastic d/o (most commonly associated with small cell carcinoma of the lung)
similar clinical presentation to MG

Front 16

mechanism behind Lambert-eaton

Back 16

ab that react to presynaptic voltage gated ca channels that inhibits the release of ACh

Front 17

radiographic appearance of osteoporotic bones

Back 17

radiolucent

Front 18

what effect do glucocorticoids have on bone

Back 18

demineralization b/c of overall catabolic effects

Front 19

cause of von recklinghausen disease of bone

Back 19

primary or 2ndary hyperparathyroidism

Front 20

gross appearance of von recklinghausen disease of bone

Back 20

osteolytic lesions
can be a brown tumor (from hemorrhage, made of bone, cystic spaces, and multinucleated osteoclsts filled with vascular stroma)
bone may appear like osteoporosis

Front 21

what is the bone alk-phos level in osteoporosis

Back 21

normal or decreased

Front 22

what is the bone alk-phos level in von-recklinghausen?

Back 22

increase

Front 23

what is the bone alk-phos level in osteomalacia and rickets?

Back 23

increased or normal

Front 24

what is the bone alk-phos level in paget dz of bone

Back 24

markedly increased

Front 25

cuase of osteomalacia

Back 25

vitamin d deficiency in adults

Front 26

cause of rickets

Back 26

vitamin d deficiency in children

Front 27

appearance of bone in rickets

Back 27

decreased calcification and excess accumulation of osteoid --> increased thickness of epiphyseal growth plats and other skeletal deformities

Front 28

clinical manifestations of rickets

Back 28

craniotabes
late closing fontanelles
rachitic rosary
harrison groove
pigeon breast
decreased height

Front 29

what is rachitic rosary

Back 29

thickening of costochondral junctions --> string of beads appearance

Front 30

what is harrison's groove?

Back 30

depression along line of insertion of diaphragm into rib cage

Front 31

morphology of paget disease of bone

Back 31

osteolytic phase (osteoclastic resorption predominates)
mixed osteoblastic/osteolytic pase (mosaic pattern)
late phase (bone density increased, thick trabeulae, prominent mosaic pattern)

Front 32

clinical complications of paget's disease of bone

Back 32

bone pain resulting from fractures
high output cardiac failure
hearing loss (narrowed auditory foramen)
osteosarcoma

Front 33

cause of scurvy

Back 33

vitamin c deficiency -> impaired osteoid matrix formation from lack of pro/lys hydroxylation

Front 34

manifestations of scurvy

Back 34

subperiosteal hemorrhage
osteoporosis
epiphyseal cartilage not replaced by osteoid

Front 35

what is the most common cause of dwarfism

Back 35

achondroplasia

Front 36

what is the genetic defect in achondroplasia

Back 36

mutation in FGF receptor 3 gene (FRFR3) on 4p

Front 37

what are the different types of fibrous dysplasia

Back 37

monostotic fibrous dysplasia (solitary lesion)
polyostotic fibrous dysplasia (multiple sites)
mccune-albright syndrome (polycystic fibrous dysplasia, precocious puberty, cafe-au-ait spots on skin, short sttature, YOUNG GIRLS!)

Front 38

what is fibrous dysplasia

Back 38

replacement of bone with fibrous tissue

Front 39

what is the most common cause for ABN?

Back 39

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