ORAL SURG zygomatic fractures

Question 1

what are the 2 categories of tx goals for zygomatic fractures?

Answer 1

1. restore facial projection/ symmetry
2. restore orbital volume/ globe position/ shape palpebral fissure

Question 2

what factors affect treatment of zygomatic fractures?

Answer 2

1. timing
2. type
3. mechanism
4. presentation

Question 3

what are the 3 categories of treatment timing for zygomatic fractures?

Answer 3

1. immediate
2. early
3. delayed

Question 4

when do you ideally want to treat a zygoma fracture?

Answer 4

early (few days-1 week) - this allows for reduction of swelling to understand anatomy better and surgical access

Question 5

what are the 2 mechanisms (fracture types) of zygomatic fractures?

Answer 5

low energy - minimal/ no comminution
high energy - comminution at segment and fracture lines

Question 6

what are the 3 overall zygomatic fracture types?

Answer 6

1. non-displaced
2. displaced, minimally comminuted
3. complex and comminuted
4. isolated zygomatic arch fractures

Question 7

what landmark is the most reliable indicator of proper reduction and orientation of zygomatic fractures?

Answer 7

zygomaticosphenoidal suture

Question 8

what type of treatment is usually given for zygomatic fractures?

Answer 8

open reduction and internal fixation (ORIF)

Question 9

in treating zygomatic fractures, what is ORIF dependent on?

Answer 9

1. degree of comminution
2. stability of fracture
3. presence of other features:
   - orbital content/ volume derangement
   - facial symmetry
   - inf orb nerve issues
   - functional issues
   - associated fractures

Question 10

what are the 4 poor outcomes of zygomatic fracture tx?

Answer 10

• inadequate tx
• inadequate exposure
• inadequate reduction
• failure to restore orbital volume

Question 11

what tx is required for a displaced, minimally comminuted zygomatic fracture?

Answer 11

ORIF

Question 12

how is a non-displaced ZMC confirmed?

Answer 12

CT scan

Question 13

tx for non-displaced ZMC?

Answer 13

non-surgical mx
monitor for facial asymmetry and functional deficit
soft diet

Question 14

tx required for displaced, minimally comminuted ZMC?

Answer 14

1. reduction alone
2. fixation (1point,2 point,3 point+orbital floor)

best managed with ORIF at 2/3 points

Question 15

what is the risk of just reducing a ZMC fracture?

Answer 15

displacement

Question 16

where is one-point fixation carried out?

Answer 16

zygomaticomaxillary buttress

Question 17

where are the 3 points for reduction?

Answer 17

frontozygomatic suture
zygomaticomaxillary buttress
inferior orbital areas

Question 18

what are the advantages of ORIF?

Answer 18

improved alignment
fixation of zygomaticomaxillary buttress provides vertical support
orbital rim exposure allows inspection of orbital floor
inspection of fractures sites prior to closure

Question 19

when exploring the orbital floor, what do we look for?

Answer 19

defects larger than 5mm on CT scan
severe displacement
comminution
soft tissue entrapment with limited upwards gaze
orbital contents herniation into max sinus

Question 20

when do you consider reconstruction of the orbital floor?

Answer 20

enophthalmos
larger defects (5-10mm)
defects posterior to the axis of the globe

Question 21

when do you consider 2 point fixation of ZMC fractures?

Answer 21

1. minimally displaced fractures
2. zygomaticomaxillary complex fracture remains stable after initial reduction with no palpable step deformity in infraorbital rim
3. minimal changes on orbital vol and globe displacement is not evident on CT scan

Question 22

when do you consider 3 point fixation of ZMC fracture?

Answer 22

instability
exploration of orbital floor required

Question 23

list the fixation methods?

Answer 23

titanium plates and screws
resorbable plates and screws

Question 24

what are the 4 sites of fixation?

Answer 24

1. frontozygomatic
2. infraorbital margin
3. zygomaticomaxillary buttress
4. zygomatic arch

Question 25

what is the aim of reduction?

Answer 25

to provide force in the direction opposite to that which caused the fracture and to re-approximate the bone to the original position

Question 26

what are the reduction options?

Answer 26

1. stab incision and intro of an instrument 2. intra-oral approach - vestibular incision 3. screw insertion 4. carroll-girard T-bar screw

Question 27

what does stab incision and instrument reduction involve?

Answer 27

introduction of an instrument (percutaneous bone hook) to hook under the bone to provide traction

Question 28

what does the intra-oral reduction approach involve?

Answer 28

vestibular incision and introduction of bone hook to hook under bone and provide traction

Question 29

what does screw reduction involve?

Answer 29

insert screw percutaneously and wire threaded through to manipulate

Question 30

for isolated arch fractures, where can you approach from?

Answer 30

oral or temporal

Question 31

describe gillies temporal reduction?

Answer 31

incision in hair line - superior and anteriorly to the helix of the ear (avoid the superficial temporal artery) dissect temporalis fascia incise temporalis fascia introduce instrument and navigate beneath zygomatic arch introduce elevator to reduce no requirement for fixation

Question 32

what are the 2 gillies temporal instruments and what do they do?

Answer 32

bristow - lifts laterally and superiorly rowe - provides traction through additional handle

Question 33

explain fixation of the frontozygomatic suture?

Answer 33

surgical exposure of suture apply mini plates and screws

Question 34

explain fixation of the zygomaticomaxillary buttress?

Answer 34

intraoral vestibular approach plates along fracture line and screws in place

Question 35

what does 3 point fixation include?

Answer 35

frontozygomatic suture zygomaticomaxillary buttress infra orbital margin

Question 36

where does 2 point fixation include?

Answer 36

frontozygomatic and zygomaticomaxillary butress regions

Question 37

describe orbital floor repair/ grafting?

Answer 37

Molded orbital floor plate - orbital contents are lifted and plate placed underneath to replace unstable fractures, supporting contents of the orbit

Question 38

what does 4 point fixation include?

Answer 38

reconstruction of the zygomatic arch through a bicoronal flap

Question 39

list the complications to ZMC surgery?

Answer 39

pain facial asymmetry scarring bleeding hardware failure infraorbital nerve paraesthesia temperature sensitivity facial paresis or paralysis poor cosmetic result trisimus

Question 40

what does an eye exam include?

Answer 40

visual activity visual fields extraocular movements

Question 41

what are the complications of orbital reconstruction?

Answer 41

decreased visual activity ectropion/ entropion/ lip malposition corneal exposure/ abrasion ptosis epiphora diplopia blindness SOFS RBH+OCS