musculoskeletal system Flashcards
osteoblasts are derived from what?
mesenchymal “osteoprogenitor” cells
osteoclasts are derived from what?
granulocyte/moncyte
primary idiopathic osteoporosis =
senile or postmenopausal
–bone loss = 2 phases: 1st= slow & 2nd = woman speed up
secondary osteoporosis =
- -low dietary calcium/poor assimilation of calcium
- -endocrine disease = hypogonadism, cushing’s, hyperparathyroidism, hypopituitarism
- -pregnancy
- -malabsorption//malnutrition
osteoporosis morphology
- -greatest bone loss is in trabecular bone
- -vertebral bodies, proximal femur & distal radius are most commonly affected
osteoporosis morphology
in woman the vertebral bodies are progressively disabled
a) Cod fish vertebrae
b) Schmorl’s nodes
c) Crush fractures
Von Recklinghausen’s Disease of Bone
advanced hyperparathyroidism
- -month-eaten X-rays
- -“brown tumors”
- -loss of lamina dura
paget’s disease
reabsorbed bone looks “tile-like mosaic”
Stages = hot –> mixed –> cold
–monostotic = 15% ~tibia
–polyostotic = 85%
osteomyelitis
infection of marrow
- -pyogenic osteomyelitis
- -STAPH. aureus = adult
- -H. influenza & B. hemolytic strep = child
- -severe = necrotic sequestrum surrounded by an involucrum
- -Brodie’s abscess = small intraosseous abscesses that are “walled off” (tibia & long bones)
tuberculous osteomyelitis
- -grow nodules most common in lungs
- -locations = in spine: POTT’S DISEASE
malignant tumors (primary & secondary)
primary = mesenchymal cells
–chondrosarcoma, Ewing’s sarcoma, osteosarcoma**, malignant giant cell
secondary = carcinomas
osteosarcoma
most common primary bone
Primary = 75% = age 10-25
morphology = codman’s triangle = zone of reactice bone that forms at angle of periosteal reflection
chondrosarcoma
- large bulky masses
- pelvis most common
Ewing’s sarcoma
highlt malignany & typically in marrow
commonly associated w/ fever, swelling, anemia
Giant cell tumor (osteoclastoma)
clin features = soap bubble appearance
- 20-55 age
- majority are benign
Duchenne (muscular dystrophy)
X-linked - pelvis & legs
fatal 2-3yrs
mutation in the gene which produces dystrophin
*becker = similar but mild form
facioscapulohumeral (muscular dystrophy)
autosomal dominant
mild severity
face & shoulders
limb girdle
autosomal recessive
moderate severity
pelvis & shoulders
myasthenia gravis
block at the myoneural junction (aka- antibodies stop ACh)
-thymic hyperplasia
osteopgenesis imperfecta
“brittle bone disease”
- -osteopenia =thinning of bone
- -blue sclera -choroid shows thru
- -hearing loss
- -small teeth
osteppetrosis
“marble bones” aka-Albers-Schonberg
–overgrowth or cortex & medullary cavity
- -malignant pattern = autosomal recessive condition
- -adult pattern = milder autosomal dominant
Achondroplasia
abnormality in epiphyseal plates = dwarfism
marfan’s syndrome
congenital disorder = CT = changes in skeleton, eyes, and cardiovascular system
–due to defect in fibrillin (chromosome 15)
rhabdomyolysis =
rupture of skeletal muscle