Bone Pathology Flashcards
1
Q
- Hematogenous spread by bacteremia from trivial causes
- Causes worm eaten lytic lesions showing necrotic resorbing bone masses used as a scaffold by osteoblasts to form new bone
- Marrow spaces replaced by pus
A
Osteomyelitis
2
Q
- Type 1 collagen is defective with inadequate bone formation resulting in thin cortices and trabeculae
- Mistaken for child abuse
- Autosomal Dominant
- Feature: dentinogenesis imperfecta and blue sclera
A
Osteogenesis Imperfecta
3
Q
- Osteoclasts lack the ability to remodel bone, causing obliteration of marrow space
- Marrow crowded out, causing myelophthisic anemia and extramedullary hematopoiesis with hepatosplenomegaly
- Deafness and Blindness due to constricted nerve ostea
- Dense bone easily infected causing osteomyelitis
- Autosomal Dominant most common and compatible with survival
- Autosomal Recessive causes death by anemia
A
Osteopetrosis - Marble Bone Ds
4
Q
Explain how Estrogen is protective in Osteoporosis of Post-Menopausal Women.
A
- Counter acts cytokines (IL-1, 6, TNF) by monocytes that cause resorption by:
- Augmenting RANK receptor
- Recruiting osteoclasts
- Stimulates OPG (inhibits osteoclasts)
5
Q
- Spontaneous wedge shaped infact of medullary subchondral bone mostly in the head of femur
A
Aseptic (Avascular) Necrosis
6
Q
- Increased remodleing not in response to physiological demands
- Increased thickness of architecturally weak bone
- Disease of Elderly
- Cause - paramyxovirus
- Cotton wool appearance in skull
- Increase in skull (hat) size
- Maxillary expansion
- Complication of High CO Failure
- Dx - elevated alkaline phosphatase
A
Paget Disease - Osteitis Deformans
7
Q
- Develpmental bone disease of continued production of immature bone matrix
- A switch for bone growth is turned on
- Non-heritable somatic mutation
- Continual production of cAMP (causes bone matrix formation)
- Severity depends on how early in embryogenesis the mutation occurs
- Begins in childhood, stopping after growth spurt
- Chinese Character Lettering - trabeculae form without regard to physiologic demands
- Woven bone matrix forms metaplastically from stroma, without osteoblastic rimming
A
Fibrous Dysplasia
8
Q
What is the worst form of Fibrous Dysplasia?
A
Albright Sx - severe polyostotic (many bones affected) fibrous dysplasia + precocious puberty in females; mutation occurs in the embryo
9
Q
- X-linked Dominant
- Kidney can’t resorb phosphate (it is excreted in urine)
- Short stature
- Elongated pulp horns stretch all the way to the DEJ, resulting in exposure upon tx
A
Vitamin D Resistant Rickets - Hypophosphatemia
10
Q
- Deficiency of tissue alkaline phosphatase
- Hammared copper skull appearance
- Wide pulp canals
- Early deciduous tooth loss due to lack of cementum
- Dx Tests:
- urinary phosphoethanolamine
- Low serum alkaline phosphatase
A
Hypophosphatasia
11
Q
- Adenoma secreting PTH, causing hypercalcemia
- Ca is leached out of the bone into the blood, leaving rarefied bone or giant cell lesions composed of osteoclasts (brown tumor)
- High serum Ca –> Metastic calcification with:
- depostion in kidneys, pancreatic ducts
- causes gastrin secretion (peptic ulcers)
A
Primary Hyperparathyroidism
12
Q
- Compensatory PTH release triggered by low serum Ca, usually due to phosphate retention seen in kidney failure
A
Secondary Hyperparathyroidism
13
Q
- Benign neoplasm of bone
- Tumor composed of mature bone
- Projects as a slow growing bony mass
- Multiple osteomas of facial and jaw bones signal Gardner Sx
A
Osteoma
14
Q
- Small tumor, not clinically noted
- Long bones, rarely jaws
- Sever pain at night - relieved by aspirn
- Pain produced by prostaglandin E produced by osteoblasts
- Men age 10-20
- Histology shows osteoblasts producing bone
A
Osteoid Osteoma
15
Q
- Large tumor
- Most cases in spine; some in jaws
- Dull Pain - not relieved by aspirin
- Men age 10-20
- Histology shows osteoblasts producing bone
A
Osteoblastoma
