External skeletal fixation (internal fixation) Flashcards Preview

Surgical skills > External skeletal fixation (internal fixation) > Flashcards

Flashcards in External skeletal fixation (internal fixation) Deck (31):
1

What must there be for external skeletal fixation to be effective?

three tranfixation pins in the proximal fragment and three pins in the distal fragment and each pin must fully pass through both cortices of the bone (fewer if IM pin as well)

2

What are benefits of external skeletal placement and removal?

1. relatively sparing of the blood supply
2. usually removal does not require second surgery

3

What are benefits of external skeletal placement and removal?

1. relatively sparing of the blood supply
2. usually removal does not require second surgery

4

What is the technique of external skeletal fixation?

A bone is splinted by passing fixation from the outside of the body through both cortices of the bone in a more or less transverse fashion. Fixation pins are then attached to at least one external connnecting bar. can be combined with IM pin

5

What are transfixation pins?

things that stick into the bone, attach to connecting bars (smooth or threaded--better grip)-

6

What is negative vs positive profile?

in negative profile the threads are cut into the pin. in positive profile the thread is added to the pin

7

What half pins vs full pins? (transfixation pins)

half pins only attach to one connecting bar (end threaded)
full pins have both ends attached to connecting bars (centre threaded)

8

What are clamps?

the grip the transfixation pins as well as the connecting bar.

9

What are clamps?

they grip the transfixation pins as well as the connecting bar. (can use epoxy etc if no clamps)

10

What are connecting bars?

an outside of the limb scaffold that you attach the transfixation pins to.

11

What are the advantages of rod and clamp system?

1. adjustable after you put it in place

12

What are the disadvantages of rod and clamp systems?

1. the transfixation pins have to be in a straight line and of similar size
2. the fracture fragments may not give enough room to put enough pins

13

What are advantages of acrylic connecting bars?

1. tansfixation pins can be of varying sizes, don't need to be in a stright line

14

What is the disadvantage of acrylic connecting bars?

not adjustable

15

What is a cool trick that can do for birds, puppies, cats?

once transifxaiton pins are placed, bend them and the IM pin if present so parallel to limb, then wrap in acrylic putty/thermoplastic

16

What are the 4 classic types of ESF configuration?

1. Type Ia fixator
2. Type IIa fixaor
3. Type Ib fixator
4. Type III fixator

17

What are the 4 classic types of ESF configuration?

1. Type Ia fixator
2. Type IIa fixaor
3. Type Ib fixator
4. Type III fixator

18

What is type Ia fixator?

a unilateral uniplanar fixator--half pins and one bar. weakest configuration. in young animals and perfectly reduced transverse fractures

19

what is a type II fixator?

a bilateral uniplanar fixator. two full pins, two connecting bars and some half pins (more pins, stronger apparatus)

20

What is a type Ib fixator?

a unilateral biplanar fixator--two type Ia fixators at 90 degrees. even stronger if have a bar between the connecting bars

21

what is a type III fixator?

a bilateral biplanar fixator. type II fixator + type Ia fixator. very very strong. But the bone may not get loaded and thus not heal so not used that much

22

What is an IM pin-ESF tie in?

use an IM pin and leave it long. add half pins and have the pins and the IM pins joined to a connecting bar

23

What is transfixation casting?

adding transfixation pins to a cast to hold thhe proximal fragment up to prevent compression. most often large animal

24

What is circular external skeletal fixation

use rings connected with rods.
thin wires under tension run through the bones

25

What is circular external skeletal fixation

use rings connected with rods.
thin wires under tension run through the bones. Can hae hybrids with regular ESF

26

When are circular external skeletal fixators used?

1. when there are short proximal or distal fragments to be dealt with.
2. can grow new bone by distraction osteogenesis

27

What are the "rules" of ESF pins?

1. 3-4 pins per fragments (1-2 if have IM in)
2. predrill all positive profile threaded pins while a guide hole smaller than threads
3. if using smooth pins, angle them, if positive profile, angle or straight
4. ALL transfixation pins (includes half pins!!!) must FULLY penetrate BOTH cortices of the bone
5. connecting bars should be a finger's width from the skin
6. transfixation pins are placed through stab incisions in the skin. cover the pad and soft tissue around pins with Robert Jones bandage until 5 days (granulation tissue)

28

What are the advantages of ESF (6)

1. minimal blood supply disruption
2. hardware removal can be done under sedation without surgery
3. fixator removal can be done in stages to gradually transfer forces back to bone
4. since ESF placement does not require anatomic reconstruction of bone, it can be used to treat highly comminuted fractures
5. good way to deal with fractures with very short proximal or distal fragments
6. sometimes cheap

29

What are the advantages of ESF (6)

1. minimal blood supply disruption
2. hardware removal can be done under sedation without surgery
3. fixator removal can be done in stages to gradually transfer forces back to bone
4. since ESF placement does not require anatomic reconstruction of bone, it can be used to treat highly comminuted fractures
5. good way to deal with fractures with very short proximal or distal fragments
6. sometimes cheap

30

What are the disadvantages of ESF?

1. not good for bones that are surrounded by muscle, trunk
2. hardware must be removed!

31

What is ESF a particularly good choice for?

1. open fractures and degloving injuries
2. highly comminuted fractures (if have IM pin tie in)
3. fractures with short proximal or distal fragments
4. stabilization of corrective osteotomies
5. distraction osteogenesis