Musculoskeletal Flashcards
hereditary disorder of bone growth; mutation of FGFR3; impaired maturation of cartilage that affects all bones; major cause of dwarfism
achondroplasia
short stature; shortened proximal extremities; bowed legs; normal torso length; large head to body size; lordotic posture (excessive inward curvature of lumbar vertebrae)
achondroplasia
heterogeneous group of heritable connective tissue disorders; mutations in either the COL1A1 or COL1A2 genes, which guide type 1 collagen formation
osteogenesis imperfecta
most common and least severe form of osteogenesis imperfecta; opalescent teeth
type 1
most severe form of osteogenesis imperfecta
type 2
most severe form beyond perinatal period of osteogenesis imperfecta
type 3
form of osteogenesis imperfecta where blue sclera fade with age
type 4
cortical bone appears attenuated; reduced bone matrix production; bone architecture remains immature throughout life, with woven bone failing to transform to lamellar bone
osteogenesis imperfecta
treatment for osteogenesis imperfecta
bisphosphonate therapy
hereditary disorder characterized by increased bone density; secondary to defect in osteoclastic function; thickening of cortical bone and sclerosis of cancellous bone
osteopetrosis
which form of osteopetrosis?: normocytic anemia; symptoms secondary to cranial nerve pressure; pathologic fracture; skull deformities, hypertelorism; delayed tooth eruption; autosomal recessive
infantile (malignant) form
which form of osteopetrosis?: milder, typically detected upon routine radiograph; no anemia; no cranial nerve compression; uncommon pathologic fracture; osteomyelitis; autosomal dominant
adult (benign)
numerous osteoclasts; lack of Howship’s lacunae; dense bone formation
osteopetrosis
porous bones, reduced bone mass resulting in increased bone fragility; can by primary or secondary to a variety of conditions; most common: senile, post-menopausal
osteoporosis
which demographic is most prone to osteoporosis?
caucasian females
fractures of vertebrae, pelvis, femur; kyphosis (overcurvature of thoracic vertebrae, hunchback)
osteoporosis
disease of bone characterized by abnormal resorption and deposition of bone; unknown etiology; possible viral etiology; recent gene mutations have been identified
pagets disease of bone
older individuals; monostotic or polyostotic; thickened, enlarged, and weakened bones; often painful
pagets disease
maxilla>mandible; enlarged alveolar ridges; may see spacing of the teeth
pagets disease
early - decreased radiodensity and altered trabeculation; later - patchy, sclerotic bone (cotton wool); hypercementosis
pagets disease
increased serum alkaline phosphatase; normal calcium and phosphorous levels; elevated urinary hydroxyproline
pagets disease
osteoblastic formation and osteoclastic resorption of bone; basophilic reversal lines (mosaic or jigsaw pattern)
pagets disease
… develops in about 1% of pagets disease patients
osteosarcoma
defective mineralization of bone matrix; due to vitamin D deficiency
rickets and osteomalacia
in infancy/childhood; bowing of legs; Rachitic rosary (prominence of the costochondral junction)
rickets
in adults; diffuse skeletal pain; susceptibility to bone fracture
osteomalacia
one of the most common pathologies affect bone; causes- traumatic, stress (repetitive loading), pathologic (in an area of existing bone disease)
fractures
a bony … bridges the fracture
callus
inflammation of the bone and marrow; implies infection (most often bacterial); entry of microorganisms (hematogenous spread, extension from a contiguous site, compound fracture)
osteomyelitis
can be acute or chronic; sequestrum (a detached, necrotic bone fragment) formation
osteomyelitis
developmental process secondary to a postzygotic mutation in the GNAS 1 gene; typically affects children during the first or second decade
fibrous dysplasia
slowly growing enlargement of a single bone; frequently involves the jaws; “ground glass” radiograph
fibrous dysplasia (monostotic)
typically involves the long bones; pathologic fracture, pain, deformity; cafe au lait pigmentation
fibrous dysplasia (jaffe-lichtenstein syndrome)
polyostotic features; cafe au lait pigmentation; multiple endocrinopathies (sexual precocity, gigantism, etc)
fibrous dysplasia (mccune-albright syndrome)
cellular fibrous stroma; irregular shaped trabeculae of woven bone (Chinese script); skull and jaw lesions mature differently
fibrous dysplasia
most common primary malignancy of bone (excluding hematopoetic malignancies); tumor cells produce bone matrix (osteoid)
osteosarcoma
75% of cases occur before age 20; most frequently affect the distal femur/proximal tibia (knee area); fills medullary cavity, breaks through cortex; hematogenous spread to lung
osteosarcoma
which variant of tumor with chromosomal translocation t(11;22)?: shows neural differentiation
PNET
which variant of tumor with chromosomal translocation t(11;22)?: undifferentiated
Ewing sarcoma
children usually age 10-15; painful, enlarging mass; classic “onion skin” periosteal proliferation on radiographs
Ewing sarcoma/PNET
most common form of skeletal malignancy; in adults, over 75% of bone metastases originate from cancers of: prostate, breast, kidney, lung
metastatic disease
most common bones involved: vertebrae, pelvis, ribs, skull; radiographic appearance may be radiolucent, radiopaque, or mixed
metastatic disease
degenerative joint disease; often an inevitable part of aging, but biomechanical factors (weight, strength) contribute
osteoarthritis
progressive erosion of articular cartilage; increased joint friction; “joint mice” (dislodged fragments of bone and cartilage); osteophytes (excess bone growth at the edges); inflammation is secondary to degeneration
osteoarthritis
chronic, non-suppurative inflammatory destruction of the joints; unknown etiology; considered an autoimmune condition; associated with certain HLA types
rheumatoid arthritis
RA-attack against the synovial membrane
synovitis
RA-reactive fibroblastic and macrophage proliferation
pannus
collagenase/protease destruction of cartilage and bone with subsequent joint deformation
rheumatoid arthritis
25-35 years, with males younger; variable involvement from mild involvement to severe pain and deformity (anvil shape); predominantly affects the small joints of the hands and feet; rheumatoid nodules; TMJ involvement about 75%
rheumatoid arthritis
elevated rheumatoid factor; antinuclear antibodies; elevated erythrocyte sedimentation rate; possible anemia
RA
hyperplasia of synovial lining cells; hyperemia, edema, mixed perivascular infiltrate; rheumatoid nodules
RA
hematogenous spread, traumatic implantation, or direct (adjacent) spread of microorganisms; bacterial infections usually cause an acute suppurative arthritis
infectious arthritis
predisposing factors (immunodeficiency, joint trauma, IV drug abuse); gonococci, staph, strep, H influenzae; salmonella occurs in patients with sickle cell disease
infectious arthritis
episodes of acute arthritis from precipitation of urates into the joints and soft tissues; increases uric acid in blood
gout
chronic gout is associated with the development of …, leading to chronic renal failure and death in 20% of those affected
nephropathy
tophi=large aggregates of urate cyrstals and surrounding granulomatous inflammation; big toe is affected in 90% of cases
gout
3 major syndromes: progressive muscular atrophy; progressive bulbar palsy; amyotrophic lateral sclerosis (Lou Gehrig’s disease)
motor neuron disease
motor neuron disease: childhood onset; progressive limb weakness and sensory disturbances; facial muscles spared
progressive muscular atrophy
motor neuron disease: children and young adults; sensory perceptions normal; begins with difficulty in articulation or swallowing
progressive bulbar palsy
motor neuron disease: middle age; difficulty walking; spastic quadriparesis; normal senses; increased tendon reflexes; fasciculation of the shoulders and thighs; muscle atrophy and dysfunction of muscles controlled by medulla oblongata
ALS
… agents may slow the progression of ALS
antiglutamate
inflammatory disorder of skin and skeletal muscle; it is characterized by a distinctive skin rash that may accompany or precede the onset of muscle disease
dermatomyositis
classic rash- discoloration of the upper eyelids and periorbital edema; muscle weakness; dysphagia (difficulty swallowing)
dermatomyositis
perifascicular atrophy and inflammation; treatment consists of immunosuppressive therapy
dermatomyositis
absence of dystrophin; low IQ, mental retardation; progressive loss of intercostal muscles; respiratory difficulty and death from pneumonia
duchenne muscular dystrophy
abnormal dystrophin; progresses more slowly than Duchenne, with symptoms developing in later childhood or adolescence; near normal life span
becker muscular dystrophy
autoimmune disease affecting the Ach receptors of muscle fibers; results in progressive weakness of skeletal muscle; often associated with hyperplasia or thymoma of the thymus gland
myasthenia gravis
progressive muscle weakness, first apparent in the small muscles of the head and neck; inability to focus, ptosis, diplopia; difficulty chewing, dysphagia, dysarthria, repeated contraction leads to progressive weakness
myasthenia gravis
degeneration of muscle fibers; elevated serum Ach receptor antibody levels; improved muscle strength after injection of edrophonium
myasthenia gravis
malignant tumor of skeletal muscle; 3 types: embryonal, alveolar, pleomorphic
rhabdomyosarcoma
potentially rapidly growing, infiltrative mass; orbit, nasal cavity, nasopharynx
rhabdomyosarcoma
