External Fixation- Rails Flashcards Preview

Biomechanics & Surgery Exam 3 > External Fixation- Rails > Flashcards

Flashcards in External Fixation- Rails Deck (21):
1

What are the types of external fixation devices?

-unilateral frame
-circular frame
-spatial frame
-hybrid frame

2

what is the hybrid frame a hybrid of?

unilateral + circular frame

3

what is a unilateral frame used for?

-compress fx
-distract fx
-rotate bone/straighten out a bone

4

what is the advantage of a circular frame?

patients can WB

5

what is a spatial frame used for?

has "motors" that can be hooked up to a computer that can adjust for deformities over time

6

a patient has a tibial plateau fracture- what type of external fixator would you use?

hybrid frame

7

what are some advtgs that external fixation has over internal fixation?

-decreased soft tissue dissection
-immobilization of multiple regions of the affected limb with compression or distraction at different sites
-allow debridement or grafting around fixation
-immediate mobilization (circular or hybrid)
-post-op adjustment

8

what are the safe zones for the tibia?

medial and anterior surface of tibia
*this changes though as you move distally

9

what are the indicators for unilateral fixation?

-primary fusion of joints
-lengthening of bone (callous distraction)
-osteomyelitis
-Joint distraction
-comminuted fractures
-bone defect
-excessive shortening trauma
-soft tissue defects
-osteoporotic bone

10

what are the indications for unilateral fixation in the foot and ankle?

-transverse plane deformities
-brachymetatarsia
-fractures
-hallux limitus
-joint fusion

11

what is a jones fracture?

fracture that occurs at the 5th met proximal diaphyseal/metaphyseal junction

12

what is hallux limitus?

a condition involving the 1st MPJ in which there is limited motion and joint jamming

13

what is an arthrodiastasis and how is it used to treat hallux limitus?

the external fixation used to distract the proximal phalanx and the 1st met and re-establish joint space

14

what is brachymetatarsia?

congenital shortening of metatarsal (usually affects the 4th met)

15

what are the parameters for distraction that you must consider when putting an external fixator on a patient?

1. osteotomy vs. corticotomy
2. level of osteotomies
3. latency period
4. rate and frequency of distraction
5. ossification period
6. post-op management
7. complications

16

generally, where should you perform an osteotomy/corticotomy?

in good healing bone (NOT the shaft)- perform it at the proximal/distal metaphysis

17

how long is the latency period before callous distraction begins?

5 days- 2 weeks

18

what is the current recommendation for rate and frequency of distraction?

1mm/day

19

what is the rule of thumb for the time in which the bone is required to lengthen?

1:1 ration between distraction & ossification

20

what are some complications seen with external fixation?

-loss of joint motion
-subluxation/dislocation***
-delayed union or nonunion
-malalignment
-chronic edema
-neurovascular compromise
-pin site irritation/infection

21

what is a PIlon fracture?

fracture of the tibial plafond