Gen Path Exam 4 - Musculoskeletal Pathology Flashcards
What are the components of bone?
35% organic osteoid
65% hydroxyapatite (inorganic)
What is found in organic osteoid?
Type I collagen
Glycosaminoglycans
Which component of bone is responsible for rigidity and hardness?
Hydroxyapatite
What are the 2 types of bone?
Woven
Lamellar
Which type of bone is rapidly produced and has less structural integrity?
Woven
Which type of bone is involved in fetal development and fracture repair?
Woven
Which type of bone is slowly produced and has more structural strength?
Lamellar
Which type of bone has parallel collagen fibers?
Lamellar
Which cell type?
Located on surface of bone matrix
Osteoblasts
Which cell type?
Synthesize, transport, assemble bone matrix
Osteoblasts
Which cell type?
Located within bone
Osteocytes
Which cell type?
Interconnected by cytoplasmic processes through canaliculi
Osteocytes
Which cell type?
Controls Ca2+ and phosphate levels
Osteocytes
Which cell type?
Detects mechanical forces
Osteocytes
Which cell type?
Located on bone surface
Osteoclasts
Which cell type?
Specialized multinucleated macrophages
Osteoclasts
Which cell type?
Responsible for bone resorption
Osteoclasts
Which cell type?
Secrete acid and neutral proteases (MMPs) to resorb bone
Osteoclasts
Constant, regulated process of bone turnover
Remodeling
What is remodeling of bone regulated by?
Cytokines
Cell-cell interactions
What are the 4 specific things that regulate remodeling of bone?
RANK receptors
RANK ligand (RANKL)
RANK-RANKL binding
Osteoprotegerin (OPG)
Which part of regulating remodeling of bone?
On osteoclast precursors
RANK receptors
Which part of regulating remodeling of bone?
On osteoblasts
RANKL
Which part of regulating remodeling of bone?
Stimulates differentiation into osteoclasts, leads to increased bone resorption
RANK-RANKL binding
Which part of regulating remodeling of bone?
Made by osteoblasts
Osteoprotegerin (OPG)
Which part of regulating remodeling of bone?
Blocks RANK interaction with RANKL
Osteoprotegerin (OPG)
Which part of regulating remodeling of bone?
Prevents osteoclast differentiation, decreases bone resorption
Osteoprotegerin (OPG)
What category of disease?
Osteoporosis
Metabolic
Which disease?
Decreased bone density and increased fracture risk
Osteoporosis
Which disease?
Decreased bone density
Osteopenia
What are the 5 most common causes of osteoporosis?
Increased age
Postmenopause
Sedentary lifestyle
Medications
Endocrine disorders
Which disease?
Affects older adults and postmenopausal women
Osteoporosis
Which disease has the following clinical presentation?
Vertebral fractures (loss of height)
Fractures of femoral neck, pelvis, spine
Osteoporosis
In osteoporosis, fractures of femoral neck, pelvis, and spine lead to what 2 things?
Embolism
Pneumonia
Which disease?
Not detected in plain radiographs until 30-40% of bone is lost
Osteoporosis
Which disease?
Dual energy X-Ray absorptiometry (DEXA scan)
Osteoporosis
Which disease has the following tx methods?
Exercise (load magnitude/resistance training)
Ca2+ and Vitamin D
Drugs that decrease bone resorption
Osteoporosis
Which drug is used to treat osteoporosis because it inhibits osteoclast-mediated bone resorption?
Bisphosphonates
Which category of disease?
Gout
Metabolic
Which disease?
Caused by hyperuricemia -> leads to deposition of urate crystals in joins -> stimulates inflammatory response
Gout
Which disease has the following risk factors?
Age
Genetics
Alcohol
Obesity
Drugs that reduce excretion of urate
Gout
Which disease has the following clinical presentation?
Asymptomatic hyperuricemia
Acute arthritis
Period of resolution, then repeated attacks
Gout
Which clinical presentation of Gout?
Can be present for years before symptoms appear
Asymptomatic hyperuricemia
Which clinical presentation of Gout?
Sudden onset excruciating localized joint pain; often affects joint of 1st toe
Acute arthritis
Which disease is diagnosed by the following?
Elevated uric acid
Synovial fluid shows urate crystals
Gout
Which disease has the following tx methods?
Lifestyle modification
NSAIDs
Meds to lower urate levels
Gout
Which category of disease?
Osteoarthritis
Injury
Which disease?
Caused by degeneration of cartilage
Osteoarthritis