External Fixation- Rails

Question 1

What are the types of external fixation devices?

Answer 1

• unilateral frame
• circular frame
• spatial frame
• hybrid frame

Question 2

what is the hybrid frame a hybrid of?

Answer 2

unilateral + circular frame

Question 3

what is a unilateral frame used for?

Answer 3

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

Question 4

what is the advantage of a circular frame?

Answer 4

patients can WB

Question 5

what is a spatial frame used for?

Answer 5

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

Question 6

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

Answer 6

hybrid frame

Question 7

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

Answer 7

• 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

Question 8

what are the safe zones for the tibia?

Answer 8

medial and anterior surface of tibia

*this changes though as you move distally

Question 9

what are the indicators for unilateral fixation?

Answer 9

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

Question 10

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

Answer 10

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

Question 11

what is a jones fracture?

Answer 11

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

Question 12

what is hallux limitus?

Answer 12

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

Question 13

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

Answer 13

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

Question 14

what is brachymetatarsia?

Answer 14

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

Question 15

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

Answer 15

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

Question 16

generally, where should you perform an osteotomy/corticotomy?

Answer 16

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

Question 17

how long is the latency period before callous distraction begins?

Answer 17

5 days- 2 weeks

Question 18

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

Answer 18

1mm/day

Question 19

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

Answer 19

1:1 ration between distraction & ossification

Question 20

what are some complications seen with external fixation?

Answer 20

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

Question 21

what is a PIlon fracture?

Answer 21

fracture of the tibial plafond