Flashcards in Week 5 Bone Pathology- Witrak Deck (36)
Generalized decrease in bone mineralization
What is a pathological fracture?
fracture through a diseased bone- usually refers to fracture through tumorous or tumor-like bone
What molecule is required for MINERALIZATION of bone osteoid?
What do you need for healthy bone?
-Ca, P from diet
-good absorption in gut
Why is the parathyroid important?
It is the master gland for Ca regulation and bone metabolism
What is osteoporosis?
A type of osteopenia due to bone atrophy caused by an imbalance of the bone remodeling process
Who is likely to have osteoporosis?
POSTMENOPAUSAL/ SENILE women
What happens to PTH secretion in osteoporosis?
Diminished PTH secretion by parathyroid glands in response to hypocalcemic stimulus.
What is the difference between secondary and common osteoporosis?
Secondary = often more treatable/ reversible causes (ex. hyperthyroidism).
Common = everything else, if its not secondary.
Best prevention of osteoporosis? Predictor of risk?
-maximize peak bone mass while teen/young adult
-encourage weight bearing exercise and Ca supplementation
-Maternal hip fracture = strong predictor of risk
Who do anit-osteoporosis medications work?
Inhibit bone resorption
Is there a biochemical serum marker of bone formation and resorption?
NO! Not sufficiently standardized or studied
What is primary hyperparathyroidism?
Hypercalcemia due to primary hyperlasia or neoplastic enlargement of parathyroid glands
-spectrum of bony changes!
What is osteomalacia?
Decreased bone mineralization with excess osteoid due to interference with Ca, P, or Vit D metabolism
-Radiologically appears osteopenic
-may present with diffuse skeletal pain
What is a common cause of osteomalacia?
Liver or renal disease (impaired hydroxylation of Vit D)
What is osteomyelitis?
Infection of bone
Primary- from blood
Secondary- from other joint or soft tissue infection
Direct- compound fractures
Most common cause of osteomyelitis?
If sickel-cell then salmonella
Clinical presentation of osteomyelitis?
Best way to detect osteomyelitis?
bone scans/MRI scans better at early detection
What is often associated with osteomyelitis in adults?
diabetic vascular disease
Treatment for osteomyelitis?
AGGRESSIVE IV antibiotic therapy
What is avascular bone necrosis/ infarction?
Bone infarcts due to ischemia of varring/often poorly understood causations
Most common cause of avascular bone necrosis?
Prolonged Cortiocosteroid therapy
What is Paget's disease?
Deforming bone disease of middle-aged to elderly adults
-latent viral infection of osteoclasts in a genetically susceptible person
What are the three phases of paget's disease?
-Lytic (inc. osteoclast with bone resorption, increased vascularity)
-Mixed (inc. osteoclast and osteoblasts, increased vascularity)
-Sclerotic- (osteoblastic phase, most characteristic radiologically)
Clinical findings of Paget's disease?
but may see WIDENING/bowing of long bones, general WEAKENING of affected bone, causing more fractures
Biochemcial give-away of Paget's?
increased serum alkaline phosphatase (sign of bone break down) typical for active disease with normal serum calcium
Congenital disorders of type 1 collagen
-abnormal or not enough
-insufficient/inadequate collagen for normal osteoid production
-results in varying degrees of osteopenia/osteoporosis
Classifications of bone tumors by x-rays
Osteolytic- demineralizing effect
Osteoblastic- increased bone density relative to normal bone