Pathology 1 Flashcards
Failure of longitudinal bone growth (endochondral ossification) SHORT LIMBS
Achondroplasia
Constitutive activation of FGFR3
Inhibits chondrocyte formation, causing achondroplasia
DEXA Scan
determines bone mineral density
T score <-2.5 is osteoporosis
Trabecular (spongy) bone loss
Osteoporosis
Osteoporosis Type 1
Post-menopausal, increased bone resorption from decreased estrogen
Osteoporosis Type 2
senile Osteoporosis, affect men and women >70 years old
Prophylaxis for Osteoporosis
Regular Weight bearing exercise and adequate calcium and vitamin D
Femoral neck fz, distal radius (Colles) Fz
Type I Osteoporosis
Tx for Osteoporosis
Bisphosphonates, PTH, SERMs, denosumab (Mab against RANKL)
Marble Bone Disease
Osteopetrosis
Defective Osteoclasts, mutations in carbonic anhydrase II
Osteopetrosis
Thicken, dense bones prone to fracture
Osteopetrosis
Hyperactivity of osteoblasts
increase in ALP
Osteitis deformans
Paget disease of the bone, common localized disorder of bone remodeling caused by increase in both osteoblastic and osteoclastic activity
Stages of Paget (bone) Disease
Lytic - osteoclast
Mixed - osteoclast + osteoblast
Sclerotic - Osteoblasts
Quiescent - minimal osteoblast/clast activity
Hat Size increased; hearing loss from auditory foramen narrowing
Osteitis deformans (paget disease)
Mosaic Pattern of woven and lamellar bone
Osteitis deformans (paget disease)
Most common site for avascular necrosis
Femoral head due to insufficiency of medial circumflex femoral artery
Long bone Chalk Stick fractures
Osteitis deformans (paget disease)
Bone disorder caused by oversupplementation or granulomatous disease like sarcoidosis
Hypervitaminosis D