Principles of internal fixation: wiring technique (Lewis) Flashcards Preview

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Flashcards in Principles of internal fixation: wiring technique (Lewis) Deck (11)
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1
Q

What is a cerclage wire

A

Heavy gauge stainless steel wire placed circumstantially around bone

2
Q

How does a cerclage wire function

A

Neutralize rotational, bending, shearing forces, and fragment apposition

3
Q

10 rules for proper cerclage wire application

A
  1. Sufficient diameter
  2. 260 anatomic reconstruction
  3. Multiple wires
  4. Fx should be long and oblique
  5. Placed 1 cm apart
  6. Placed .5cm from tip of fx
  7. Perpendicular to long axis of bone
  8. Prevent wire from migrating
  9. Do not entrap
  10. Tight
4
Q

Why is a loose cerclage wire so detrimental

A

reduce fx healing
increase risk of infection
Rub against blood supply

5
Q

Advantage of twist knot

A

can re-tighten

Greater resistance to the cyclic forces of weight bearing

6
Q

Disadvantages of twist knot

A

decrease final wire tension
wires protrude
do not alight perpendicular to long axis during tightening

7
Q

Loop wire advantages

A

Greater final wire tension

8
Q

Disadvantage of loop wire

A

cannot re-tighten wires

more cumbersome

9
Q

3 ways to prevent cerclage wire slipping

A

hemicerclage wire
Notch bone
Place wire adjacent to or straddling an inter-fragmentary K wire

10
Q

What is a hemicerclage wire

A

drill a hole into the bone and run cerclage wire through it

11
Q

purpose of Tension band principle

A

Converts distractive (tension) forces to compressive forces