MSK Gen

Question 1

What is bone composed of?

Answer 1

Highly vascularized, metabolically active connective tissue

Made mainly of collagen type I and hydroxyapatite crystal Ca10(PO4)6(OH)2

Question 2

What happens to calcium in bone at lower pH

Answer 2

increase in the amt of Ca2+ leaving the bone at lower pH

Question 3

Bone fns

Answer 3

structure

protection

locomotion

reservoir- for Ca2+, PO4- and fat

hematopoietic and immune cell prod

endocrine- GF, cytokines, FGF23 and osteocalcin

Question 4

What does osteocalcin do?

Answer 4

↑ insulin sensitivity

↑ glucose uptake in
muscle and bones

↑ insulin secretion

↑ beta cell proliferation

↑ Testosterone and bone formation

↑ exercise capacity

osteocytes release FGF23 which ↑ phosphate excretion from kidney

kidney releases erythropoietin and ↑ RBC prod

↓ anxiety and depression

Question 5

What are the 4 design features of bone?

Answer 5

compact (strength) vs porous (low weight and more space)

rigidity vs flexibility

durability (lamellar bone) vs speed (woven bone)

balance in bone formation and reabsorption

Question 6

Describe trabecular (cancellous) bone

Answer 6

interior is porous to ↑ space and ↓ weight

and ↑ surface area to help Ca2+ that is leaching for homeostasis

Question 7

Describe medullary cavity

Answer 7

holds marrow, nerves, vessels

↑ space and ↓ weight

Question 8

Describe cortical bone

Answer 8

compact outer layer that is heavily mineralized (strong) but thin (↓ weight)

Question 9

What fills the porous bone space

Answer 9

red bone marrow- hematopoietic cells

yellow marrow- fat (as we get older)

Question 10

What bone type are vertebra mainly composed of?

Answer 10

trabecular bone

Question 11

What bone type are long bones mainly composed of?

Answer 11

cortical bone

Question 12

What bone type is the hip mainly composed of?

Answer 12

cortical bone

Question 13

Where is red marrow mainly found?

Answer 13

in flat bones such as hip, skull, breast, ribs, vertebra, shoulder blades and cancellous bones at ends of long bones

Question 14

Where is yellow marrow mainly found?

Answer 14

mainly in medullary cavity of long bones

Question 15

Why are trabecular bones more preferentially affected by pathological conditions that disturb bone remodeling?

Answer 15

they are remodeled more each year than cortical bone due to being more porous to provide Ca2+ for homeostasis

Question 16

Describe the structure of hydroxyapatite crystal Ca10(PO4)6(OH)2

Answer 16

strong and resists compression but is weak to tensile strength and shears

Question 17

Describe the structure of collagen fiber type I

Answer 17

weak but flexible to absorb bending and shear strain, resists tensile strain but is weak to compression

Question 18

What happens to hydroxyapatite crystal size in osteopetrotic individuals?

Answer 18

increase in size

Question 19

What happens to hydroxyapatite crystal size in diabetes and Paget’s disease individuals?

Answer 19

decrease in size

Question 20

What determines bone strength?

Answer 20

density
size and geometry
composition (cortical v trabecular)
matrix material property
microsctruture (lamellar vs woven)

Question 21

MC cause of bone tumors

Answer 21

Mets from lung, breast, prostate, kidney, thyroid

Question 22

Oligoarthritis

Answer 22

arthritis affecting two to four joints during the first six months of disease

Question 23

Polyarthritis

Answer 23

any type of arthritis that involves 5 or more joints simultaneously usually associated with autoimmune conditions

Question 24

ankylosis

Answer 24

abnormal stiffening and immobility of a joint due to fusion of the bones

Question 25

osteophytes

Answer 25

a bony outgrowth associated with the degeneration of cartilage at joints

Question 26

If 1 joint is painful and swollen what must you rule out?

Answer 26

septic arthritis

Question 27

Closed Fracture (aka Simple Fracture)

Answer 27

Skin over the fracture is intact

Question 28

Open Fracture (aka Compound Fracture)

Answer 28

Overlying skin is disrupted; “open wound”

Question 29

Fn of Labrum in hip

Answer 29

Increases depth of acetabular cavity creating increased surface and strength of joint

Question 30

What is the MC inj structure of the knee?

Answer 30

MCL

Question 31

Angulated fx

Answer 31

Fracture fragments are malaligned at an angle

Question 32

Segmental fx

Answer 32

Fx with at least two fracture lines that together isolate a segment of bone

Question 33

Comminuted fx

Answer 33

Fx that results in two or more fragments

Question 34

Transverse fx

Answer 34

Fx line forms a right angle with longitudinal axis

Question 35

Rhabdomyolysis

Answer 35

Rapid death of striated muscle cells often with myoglobinuria or acute renal failure

Question 36

ca that mets to bone "BLT w/ pickles and ketchup"

Answer 36

``` breast lung thyroid prostate kidney ```

Question 37

Intra Articular fx

Answer 37

Involving the joint space

Question 38

Extra Articular fx

Answer 38

No involvement of joint space

Question 39

Impacted fx

Answer 39

Fx in which one of the fragments is driven into another fragment

Question 40

Compression Fracture

Answer 40

Vertebral collapse

Question 41

Greenstick fx

Answer 41

One side broken; opposing side bent

Question 42

Occult Fracture

Answer 42

Fx that does not appear on x-ray look for hypodense area (fat pads)

Question 43

Avulsion fx

Answer 43

Release of small portion of bone at location of tendon insertion (tendon pulls bone and fxs it)

Question 44

Stable fx

Answer 44

A fracture that tends to remain in alignment after reduction

Question 45

Unstable fx

Answer 45

A fracture that tends to displace after reduction

Question 46

McCarthy Test

Answer 46

Patient is in supine position. Flex both hips and then extend the affected hip + a catch a labral tear is presen

Question 47

FABER Test

Answer 47

Patient is in a supine position. Put affected leg and on the opposite straight leg in a position of Flexion Abduction External Rotation. Apply pressure to anterior aspect of the knee lowering the test leg into further abduction. + If the leg can not be lowered parallel to the opposite leg or pain

Question 48

Fn of Labrum in hip

Answer 48

Increases depth of acetabular cavity thus, increasing surface and strength of joint

Question 49

What is the MC inj structure of the knee?

Answer 49

MCL

Question 50

Myalgia

Answer 50

Symptom of muscle-discomfort: muscle aches, soreness, tenderness, cramps with a normal CK

Question 51

Myopathy

Answer 51

Muscle weakness (not due to pain), with or without an elevated CK

Question 52

Myositis

Answer 52

Muscle inflammation

Question 53

Myonecrosis

Answer 53

Elevated CK due to death of striated muscle cells

Question 54

Rhabdomyolysis

Answer 54

Rapid death of striated muscle cells often with myoglobinuria or acute renal failure

Question 55

ca that mets to bone "BLT w/ pickles and ketchup"

Answer 55

``` breast lung thyroid prostate kidney ```

Question 56

Why do most herniated lumbar discs occur posteriorly and off to one side?

Answer 56

Posterior longitudinal ligament is strongest in the midline and the posterior-lateral annulus may bear a large share of the axial load.