Chapter 68- Facial Trauma

Question 1

best time to reduce nasal fx

Answer 1

immediately after (1-2 hr) OR
5-10d later once swelling has subsided

Question 2

how edentulous mandible affects repair

Answer 2

no cross-sectional stability
too weak to load share site w/ small bone plate
needs load-bearing reconstruction

Question 3

color of vision lost earliest with orbital injury

Answer 3

red

Question 4

Feature of all LeFort fxs

Answer 4

traverse pterygomaxillary fissure

interrupt pterygoid plates, mobile palate

Question 5

two most common mandible fx sites

Answer 5

angle

condyle

Question 6

Aspects of PE important with facial trauma

Answer 6

ABC
Cerv spine/brain
CN
Eye
Ear (hearing, hemotymp, fx)
Skull/midface/mandible
Throat: occlusion, TMJ fxn, bleed, hematoma, airway, speech, swallow

Question 7

which areas of h/n difficult to evaluate w/o sagittal/coronal recons?

Answer 7

orbital floor
mandibular condyle
frontal sinus outflow tract

Question 8

Radiographic signs of fx

Answer 8

Non-anatomic linear lucency, cortical defect, suture diastasis, overlapping bone fragment, facial asymm
soft tissue swell, periorbital/IC air, fluid in sinus (indirect)

Question 9

High vs low impact forces

Answer 9

Low are <50g (<50 times force of gravity)

Question 10

g’s that different facial bones can withstand

Answer 10

nasal- 30
zygoma- 50
mandible angle- 70
frontal-glabella- 80
midline maxilla/mandible- 100
supraorbital rim- 200

Question 11

Indications for surgery for A/P table fxs of frontal sinus

Answer 11

Ant: bony displacement causing deformity, FSOT impairment
Post: displace post table >1 table width, dural injury, CSF rhinorrhea, FSOT impairment, severely comminuted

Question 12

Approaches to frontal sinus

Answer 12

trephination, elevate anterior wall
frontoethmoidectomy using lynch incision
ORIF through laceration or coronal flap
obliteration
cranialization

Question 13

How to avoid vessel/nerve injury when raising coronal flap

Answer 13

avoid CN VII frontal branch injury by incising superficial layer of deep temporal fascia at temporal line of fusion, so elevation can be deep to this layer

osteotome to inferior lip of supraorbital/trochlear nerve foramen to allow nerve to move inferiorly

Question 14

How to treat nasal fx that occurred 10d ago

Answer 14

may not be amenable to closed reduction

may need complete healing (3-6mo) then septorhinoplasty

Question 15

3 types of medial canthal tendon injuries

Answer 15

I- single noncomminuted central fragment, MCT attach
2- central fragment comminuted
3- MCT detached

Types 2/3 need transnasal wiring

Question 16

where orbital contents leak into sinuses in blowout fracture

Answer 16

floor (0.5mm)

less often the lamina (0.25mm)

Question 17

When to perform surgery with blowout fx of orbital floor

Answer 17

enophthalmos >2mm
double vision primary or inferior gaze
EOM entrap (forced duction)
>50% floor on CT

Question 18

white eye blowout fracture

Answer 18

greenstick (child)
contents leak out floor, then bone closes, inferior rectus trapped/ischemic
white sclera, usually with nausea

Question 19

Surgical approaches to orbit

Answer 19

Floor: infraorb, subciliary, transconj (pre/post septal)
Med: transcaruncular, endoscopic, lynch (external ethmoidectomy)
Lat: infrabrow, upper lid skin crease (bleph), extended lower lid transconj with lateral canthotomy
Roof: lynch, transbrow, coronal

Question 20

risks of lynch incision

Answer 20

between medial canthus and bridge

skin scar, disinsert medial canthal tendon, damage lacrimal sac, diplopia from trauma to trochlea of sup oblique, scar

Question 21

How does transcaruncular approach compare to lynch for medial orbit access

Answer 21

rapid, less dabmage to skin/muscle layers, better cosmesis, less manipulation of lacrimal sac, MCT

Question 22

absolute indications for lateral canthotomy

Answer 22

retrobulbar hemorrhageg acute loss of visual acuity, increased IOP, proptosis
If unconscious: IOP >40 (NL is 10-21)

Question 23

Optic nerve injury manifestations

Answer 23

First: lose red color vision
Later: other colors, decreased central vision, APD, visual field defect
Tx: steroids (high dose) or surgical decomp

Question 24

traction test

Answer 24

with NOE fx, pull laterally on lower eyelid to see if MCT disrupted

Question 25

4 fractures of ZMC fracture

Answer 25

ZM suture (infraorb rim)
Arch
ZF (lateral rim)
Sphenozygomatic suture

Question 26

Vertical midface buttresses

Answer 26

resist forces of mastication
nasomaxillary (medial) from nasomaxillary to frontal bone
zygomaticomaxillary (lat)
pterygomaxillary (post)

Question 27

Horizontal buttresses

Answer 27

supports between verticals
palate
central facial buttress (malar to malar, interrupted by piriform aperture)
frontal bar
zygomatic arch A/P

Question 28

LeFort I-II-III

Answer 28

I: above maxillary alveolus…float palate
II: nasion - lacrimal bone - inferior orb floor/rim - ant wall max sinus
III: zyg bone, NF, FM sutures, orbit.

Greater wing of sphenoid prevents fx from continuing to optic canal

Question 29

Thirds of Face

Answer 29

Upper: frontal bone/sinus/lobe
Middle: nasal, NOE, orbit, ZMC, maxillary
Lower: mandible, TMJ

Question 30

Order of repairs with panfacial

Answer 30

Stable to unstable

1: nasal and zygomatic bones to cranial bone
2: mandible to maxilla
3: maxilla to nasal and zygomatic bones and cranium

Question 31

what often occurs with a parasymphyseal fx?

Answer 31

condyle fx

Question 32

bite deformity caused by condylar fx

Answer 32

open

Question 33

treatment of condylar fxs

Answer 33

only ORIF if subcondylar
if head/neck, then non-surgical
tough to ORIF b/c near CN VII, bone cannot support hardware, unfavorable due to lateral pterygoid

Question 34

Indications for ORIF of condyle fx

Answer 34

Absolute: displace into MCF/EAC, cannot get adequate occlusion, lateral extracapsular dislocation, contaminated open joint wound

Relative: Bilateral in edentulous patient if splints unavailable, splinting not recommended, bilateral with comminuted facial fxs, bilateral with: retrognathia/prognathia, open bite and periodontal problems, loss of multiple teeth, unstable occlusion, one of the condylar fx with unstable fracture base

Question 35

Why is functional therapy important with condylar fxs?

Answer 35

avoid ankylosis of TMJ

Start right after MMF removed, or right away if no MMF

Question 36

why angle is easy to fx

Answer 36

weakened by 3rd molar

thinner cross-sectional area

Question 37

Which mm pull on angle fx?

Answer 37

masseter, medial pterygoid (unfavorable)

Question 38

Which plate goes on sup border with angle fxs

Answer 38

tension plate on sup border (reduce separation with chewing)

may not need plate at inf border of angle fx b/c compresses with chewing to keep fx reduced

Question 39

Occlusion classes

Answer 39

I- MBC maxillary 1st molar contacts BG mandibular
2 retrognathia- posterior mandible
3- prognathia, anterior mandible

Question 40

Closed vs open mandible fxs

Answer 40

Closed: non-displaced, favorable, pediatric, grossly comminuted, coronoid, adult condyle (some)
Arch Bar/Ivy loop/Risdon wire/splints/dentures

Open: displaced unfavorable, atrophic edentulous, complex facial, condylar if cannot be treated by closed

Question 41

Edentulous mandible considerations: closed and open

Answer 41

Smaller, more fragile, less osteogenesis/blood supply, depend on periosteum for nourishment

Closed: gunning splints, dentures, external pin fixation

Open: heavy load bearing plates with bicortical scres (bone too weak to load share)

Question 42

Pediatric mandible fx considerations

Answer 42

Conical teeth, short roots, not amenable to MMF

6 and younger: closed

12 and older – should have permanent teeth, can do ORIF with mini plate…avoid condylar injury b/c major elongation center