Bone 1

  1. What are paraneoplastic syndromes that result in excess PTH-like substance?
    Squamous Cell Carcinoma, Renal Cell Carcinoma
  2. What's the primary cause of hyperparathyroidism?
    Parathyroid Adenoma
  3. What's the most common cause of secondary hyperparathyrodism?
    Renal Failure
  4. What's a common clinical presentation of vitamin D deficiency?
    Bone issues
  5. What's a common presentation of vitamin C deficiency?
    Bone & Bleeding issues
  6. What's the connection between primary hyperparathyrodism and pancreatitis?
    Activation of trypsin --> pancreatitis
  7. At what levels do you see symptoms of hypercalcemia? Organ calcification?
    Coma/cardiac arrest?
    • Symptoms > 11.5
    • Organs > 13
    • Coma/arrest >15
  8. What are functions facilitated by calcium levels?
    Cell signaling, neuromuscular function, bone metabolism
  9. Through what mechanisms does PTH regulate calcium?
    Renal tubular reabsorption, osteoclast stimulation, renal 1 hydroxylase activity
  10. What's the mechanism of calcitonin's suppression of Ca levels?
    Inhibits osteoclasts
  11. What's the histological findings in bone lesions?
    • Increased osteoclastic activity
    • fibrous tissue replacement of bone
    • thinned trabeculae
    • cystic spaces
  12. What are brown tumors characteristic of?
    • Hyperparathyroidism
    • Osteoclasts, giant cells, hemorrhagic debris
  13. Where are metastatic calcifications found in secondary hyperparathyroidism?
    Vessels, lung, heart, stomach
  14. What does the term Renal Osteodystrophy describe?
    Bone changes secondary to chronic renal failure (atrophied bone)
  15. What is characteristic of osteomalacia?
    Decreased bone matrix mineralization with normal matrix (vs. osteoporosis)
  16. What's the difference between parathyroid adenoma vs. carcinoma?
  17. What are lab findings in osteoporosis?
    Normal calcium, phosphate, PTH
  18. What's the mechanism of postmenopausal osteoperosis?
    • Increased cytokine --> activation of osteoclasts
    • TNF -> RANK(L)
  19. What's the mechanism of senile osteoporosis?
    Decreased osteoblast function
  20. Where are the most common fractures found in osteoporosis?
    • Vertebrae, weight bearing bones
    • Usually asymptomatic
  21. What's the best way to diagnose osteoporosis?
    Bone mineral densitomerty
  22. What's the effect of estrogen on bone?
    Reduction in osteoclastogenensis;
  23. What are risk factors for bone fractures?
    Fracture history, glucocorticoid use, cigarette smoking, alcoholism, family history of fracture, low bodyweight
  24. What is Osteits Deformans?
    Paget Disease
  25. What is the gold standard for assessing bone mineral density?
    • Dual-Energy x-ray absorptiometry (DXA) of spine & hip
    • Osteopenia: (-1.0) - (-2.5) SD
    • Osteoperosis: < -2.5 SD
  26. In what disease is morning joint stiffness MOST common?
    Rheumatoid Arthritis
  27. What clinical findings are present in Rheumatoid Arthritis?
    Morning stiffness, bilateral pain, MCP joint involvement, swan neck deformities
  28. What is a swan-neck deformity and when is it found?
    Hyperextension of PIP; RA
  29. When are osteophytes found?
    Bony outgrowths found in osteoarthritis
  30. What are risk factors for osteoarthritis?
    Obesity, diabetes, ochronosis, hemochromatosis, trauma/overuse, bone/joint deformities
  31. Where are common joints of involvement for OA?
    • Large: intervertebral, hips, knees
    • DIP
  32. What's the most commn joint disorder in the US?
  33. What are heberden nodules and when are they found?
    Osteophytes at DIPs in OA
  34. What are bouchard nodules and when are they found?
    Osteophytes at PIP joints found in OA
  35. What histological findings are characteristic of RA in the joints?
    Synovial hyperplasia, lymphocytosis, involvment of smaller joints
  36. What are complications of HFE gene mutations?
    • Hemochromatosis:
    • Iron absorption, cirrhosis, cardiomyopathy, diabetes, OA
  37. What's the common demographic of osteosarcoma?
    • 10-20 y/o
    • Elderly with prior Paget's Disease/radiation exposure
    • Males
  38. Where are common sites of involvement for Osteosarcoma?
    • Young - femur or tibial metaphysis
    • Old - axial or craniofacial
  39. What's the common gross presentation of osteosarcoma?
    • Blastic/lytic masses with infiltrative margins
    • Elevation of periosteum = Codman Triangle
  40. Where are most common metastases locations of osteosarcoma?
    • Lungs - 80%
    • Bones - 15%
  41. What's the definition of and osteosarcoma?
    Any malignant cell that produces osteoid (regardless of what else may be produced)
  42. What's the most common primary bone tumor?
  43. What are common mutations found in osteosarcomas?
    • Sporadic: RB & p53
    • Familial: Rb, associated hereditary retinoblastomas
  44. What are common clinical symptoms of Paget Disease?
    • asymptomatic
    • bone pain, fractures, anterior tibial bowing, warmth & tenderness, cardiac failure
  45. What's a common lab presentation for paget disesase?
    • Increased alkaline phosphatase (5x)
    • Increased urinary hydrokyproline
  46. What's the most common location for Paget's disease?
    • Axial skeleton (80%) - also skull, tibia, pelvis
    • Polyostotic (85%)
  47. What's the histological pattern of Paget's disease?
    Mosaic pattern from disorganized degeneration/regeneration
  48. What are the stages of Paget's disease?
    • 1. osteolytic
    • 2. mixed
    • 3. osteosclerotic
  49. What are complications of paget's disease?
    • Skeletal deformities
    • Nerve compression (deafness)
    • Increased vascularity (AV shunting -> high output cardiac failure)
  50. What neoplasmic sequelae follow Paget's diesease?
    Osteosarcoma, MFH, chondrosarcoma in 10%
  51. What are most commonly involved sites of chondrosarcoma?
    Axial skeleton (ribs, shoulder, pelvis), proximal femur & pelvis
  52. What are the most common etiologies of chondrosarcomas?
    • Primary (85%) from previously normal bones
    • Secondary (15%) from benign precursors
  53. What's a histological characteristic of chondrosarcoma?
    2+ cells per lacuna
  54. What's the metastasis profile of chondrosarcoma?
    • Typically slow growing (slow to metastsize)
    • De-Differentiated chondrosarcomas: rapid metastases in lung, brain, bone
  55. What's the metastasis profile of osteosarcomas?
    20% have pulmonary metastases at diagnosis
Card Set
Bone 1
Lab Notes for Exam 4