Exam 6 Radiology/fractures/ultrasound

Question 1

What is radiopaque?

Answer 1

relative impenetrability to x-rays

Question 2

What is radiolucent

Answer 2

relative penetrability to X-rays

Question 3

What should be done prior to ordering an x-ray?

Answer 3

an excellent history and physical

Question 4

What is the metaphysis? Diaphysis?

Answer 4

Metaphysis is the end of a bone proximal to the growth plate, diaphysis is the shaft of a bone

Question 5

What is an epiphysis? Epiphyseal plate?

Answer 5

The part of the bone distal to the growth plate; its the growth plate

Question 6

What is an apophysis? Apophyseal plate?

Answer 6

A growth plate that has a tendon attached to it (tibial tuberosity); A growth plate under an apophysis

Question 7

What should always be done with fractures?

Answer 7

Obtain at least 2 views of the involved bone, ideally in perpendicular planes; look for indirect signs of fracture

Question 8

What are indirect signs of a fracture?

Answer 8

soft tissue swelling, obliteration or displacement of fat stripes, periosteal and endosteal reaction/thickening, buckling of cortex, double cortical line

Question 9

What is a supracondylar fracture; intraarticular?

Answer 9

Supra is just above, intraarticular in a break of half of the articular surface

Question 10

What is a comminuted fracture?

Answer 10

a break off of the bone with a complete transverse fracture

Question 11

What is the differential diagnosis of arthridities?

Answer 11

Osteoarthritis, Inflammatory arthritis, Seronegative spondyloarthropathies, crystal depositiona arthropathy, metabolic/endocrine, infectious

Question 12

What is an important clinical presentation that can tell you which arthritis a patient has?

Answer 12

the distribution of the involved joints

Question 13

What does osteoarthritis look like in an x-ray?

Answer 13

marginal osteophytes, cortical irregularity, subchondral sclerosis, subchondral cysts, joint space narrowing

Question 14

What does an xray of rheumatoid arthritis look like?

Answer 14

Periarticular osteoporosis, joint effusion, joint space narrowing, articular erosions/destruction, synovial cysts, deformities

Question 15

What is the composition of bone?

Answer 15

Organic-30% (cells, matrix/collagen), Mineral-70%(hydroxyapatitie, MG, Na, K, Fl, Cl)

Question 16

What is intramembranous ossification?

Answer 16

Mesenchymal progenitor cells differentiate into osteoblasts which then directly form bone

Question 17

What is endochondral ossification?

Answer 17

Mesenchymal progenitor cells differentiate into chondrocytes, initially forming a cartilage intermediate that is replaced as bone is regenerated

Question 18

Where is most cortical/compact bone?

Answer 18

Long bones

Question 19

Where are trabecular/cancellous bone

Answer 19

mostly flat bones

Question 20

What is the structure of cortical bone?

Answer 20

Haversian systems, nutrient arteries, periosteum, endosteium

Question 21

What is the structure of trabecular bone?

Answer 21

mostly a lattice system instead of a Haversian system

Question 22

What are the two types of bone?

Answer 22

Woven and lamellar

Question 23

What is the difference between woven and lamellar?

Answer 23

Woven is laid down pretty quickly, but is transient and replaced by lamellar bone for long term structure

Question 24

What happens in the initial fracture?

Answer 24

Trauma > injury to cells, blood vessels, bone and soft tissue > hematomas form and damage to blood vessels leads to osteocyte death and necrotic tissue

Question 25

What happens in the inflammatory phase of a fracture?

Answer 25

Release of cytokines leads to vasodilation (edema) and migration of inflammatory cells (initially neutrophils, then macrophages and lymphocytes)

Question 26

What does migration of inflammatory cells to the site of the fracture lead to?

Answer 26

release of cytokines to increase angiogenesis leading to increases in fibroblasts and osteoblasts for new matrix, and osteoclasts to resorb necrotic tissue

Question 27

T/F: Osteocytes are involved in fracture repair?

Answer 27

FALSE- they aren’t!!!

Question 28

What decreases pain of a fracture initially?

Answer 28

the formation of a soft callus to lessen movement

Question 29

What do pluripotent mesenchymal cells differentiate into?

Answer 29

osteoblasts, chondrocytes, fibroblasts

Question 30

What do monocytes differentiate into?

Answer 30

osteoclasts

Question 31

What does fracture healing depend on?

Answer 31

recruitment, proliferation, accumulation and differentiation of pluripotent mesenchymal cells at the site of the fracture

Question 32

What does the transition from a soft callus to a hard callus look like?

Answer 32

Intramembranous bone formation at the periphery (proximal and distal to the injury site, endochondral bone formation overlying the site

Question 33

What is a clinical union?

Answer 33

when the fracture site becomes stable and pain free

Question 34

What is a radiographic union?

Answer 34

plain radiographs show bone trabeculae or cortical bone crossing the fracture site

Question 35

What happens in the remodeling phase of fracture healing? How long does it last?

Answer 35

Replacement of woven bone with lamellar bone, resorption of unneeded callus; May continue for years

Question 36

What are some variables that influence fracture healing?

Answer 36

Injury (soft tissue damage, bone comminution and displacement, location of bone injury), Patient’s age, Treatment variables (fracture stabilization)

Question 37

T/F: an internal plate repair affects healing process? How?

Answer 37

True, fracture skips over woven bone formation and directly moves to lamellar bone, leading to not as good of a fracture healing

Question 38

T/F: a Salter-Harris class III fracture is something to worry about in children? Why?

Answer 38

True; affects the proliferating zone of cells at the distal half of the growth plate?

Question 39

Where is the proliferative, hypertrophic and metaphysis section of a growth plate?

Answer 39

Proliferative is at the distal part, hypertrophic is where cells continue to mature until they are added onto the metaphysis. DON’T HURT THE PROLIFERATIVE ZONE