Test 1: pin and wires

Question 1

the thicker the wire =

Answer 1

the higher the tensile strength (resistant to being pulled apart)

the bigger the number the thinner the wire

18 gage is bigger then 24 gage

Question 2

4 ways to use orthopedic wire

Answer 2

cerclage wire
tension band
interfragmentary wire
ligament substitute

Question 3

Answer 3

cerclage wire

Question 4

how to use cerclage wire

Answer 4

wire wrapped around bone column and compressed

can be spooled wire or eyed wire

use for long oblique or spiral fractures

need at least 2 wires for stabilization

needs to be 0.5 cm from fracture ends

needs 2-3 twists to close, do not bend over

Question 5

cerclage wire are used for what type of fractures?

Answer 5

long oblique or spiral fractures

Fracture line ≥ 2x the diameter of the bone

Must be able to reconstruct bone column (anatomic reduction)

Question 6

how many cerclage wires are need for stabilization

Answer 6

at least 2
needs to hold fragments in place

Question 7

where to place cerclage wire

Answer 7

at least 0.5cm from fracture ends, spaced 0.5-1 x bone diameter apart

place perpendicular to bone

Question 8

can you use cerclage wire alone?

Answer 8

no, not strong enough

Question 9

when to use tension band wires?

Answer 9

avulsion fracture and repair some osteotomies

Question 10

— is fixation used to neutralize the pull of muscle/tendons on the fracture fragment

Answer 10

tension band wire

used for avulsion fractures and some osteotomies

Question 11

Answer 11

pins with tension band wire to reduce pull of muscle/tendon of the fracture fragment

Question 12

tension band wires should be — to the fracture and — to each other

Answer 12

perpendicular

parallel

should penetrate the near and far cortex

Question 13

to place a tension band wire, you should drill hole —

Answer 13

through both bone cortices distal to fracture line to pass wire

distance below the fracture line should = distance between fracture line and insertion point of K-wires

Question 14

for tension band wire you should pass the wire through the hole and around the — and then back —

Answer 14

the end of the pin

back to the other end of the wire creating a figure 8

Question 15

when to use interfragmentary wire

Answer 15

for not weight bearing bones

used to hold pieces together/ acts as suture

Simple fractures of flat, non-weight bearing bones that interdigitate well

Most commonly used for certain mandibular and
maxillary fractures

Question 16

steinmann pins are also called

Answer 16

intramedullary pins

Question 17

steinmann pins range in size from —

Answer 17

1/16 “ to 1/4”
(2-5 mm)

can be trochar or chisel point
smooth or threaded

made from 316L stainless steel cylindrical rods

Question 18

— are very small steinmann pins

Answer 18

kirschner wires

easily bent
0.035”- 0.062”

Question 19

5 ways to use steinmann pin

Answer 19

Intramedullary placement
Cross pinning
Diverging pins
Skewer pin
Tension band constructs

Question 20

advantages of steinmann pins

Answer 20

inexpensive

used for smaller surgeries
less surgical time
easy to remove if needed

Question 21

disadvantages of steinmann pins

Answer 21

only resist bending forces
pins can move

limited application as primary fixation implant

Question 22

IM pins are places in medullary canal to help restore —

Answer 22

length and maintain alignment

only resist bending forces

Question 23

what bone is contraindicated for IM pin placement

Answer 23

radius

IM pin can only resist bending forces, can be used in humerus, femur, tibia, ulna, metatarsals and metacarpals

usually needs other fixation method

Question 24

what to avoid when placing IM pin

Answer 24

avoid joint surface

end point is metaphysis

Normograde vs
Retrograde placement

Pin Diameter Choice:
 With cerclage: 70% canal fill
 With plate: 35-40% canal fill

Question 25

IM pin as primary repair should be —% of canal

with plate — %

Answer 25

70

35-40% canal fill

Question 26

Answer 26

normograde pinning

Question 27

Answer 27

retrograde pinning

Question 28

what to use for simple transverse fracture close to the joint

Answer 28

cross pinning

Typically young animals (Salter Harris type I and II)

Fragments must have good contact to provide load sharing

Question 29

cross pining will counteract — forces

Answer 29

rotational and bending

used for simple transverse fractures close to the joint

Question 30

in cross pinning pins cross above or below fracture line?

Answer 30

above

Question 31

salter harris type — and — can be fixed with cross pinning

Answer 31

1 and 2

Question 32

what technique is used for salter harris 1 fracture of proximal humerus and femoral head

Answer 32

diverging pin technique

will promote normal physeal anatomy and bone growth

Question 33

what is interlocking nail fixation

Answer 33

IM pin and attached plate

will counter bending, rotation, tension and compressive forces

jig used to place bolts

used for diaphyseal and comminuted fracture

Question 34

when to use interlocking nail

Answer 34

diaphyseal comminuted fractures