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Facial Plastics & Trauma > Trauma - General, Mandible, Maxilla > Flashcards

Trauma - General, Mandible, Maxilla Flashcards

1
Q

Differentiate Primary vs Secondary Bone, and trabecular and compact bone

A

Primary Bone: Temporary, random arrangement of collagen (=immature, woven bone)

Secondary Bone: Mature bone, orderly collagen fibers and osteoblasts (=mature, lamellar bone)

Trabecular bone = cancellous or spongy bone
Compact bone = dense or cortical bone.

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2
Q

Describe the 2 mechanisms of osteogenesis

A
  1. ENDOCHONDRAL OSSIFICATION
    - Characteristic of long bone ossification
    - Involves the replacement of hyaline cartilage with bone from the perichondrial matrix
    - Perichondrium around the hyaline cartilage “model” is infiltrated with osteoblasts
  2. INTRAMEMBRANOUS OSSIFICATION
    - Involves the replacement of sheet-like connective tissue with bone
    - Includes the flat bones of the skull and irregular bones
    - Mesenchyme becomes osteoblasts, which produce randomly oriented collagen fibers within a matrix known as primary bone
    - Immature primary bone is then replaced by secondary bone
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3
Q

What are the two main types of bone healing?

A

PRIMARY BONE HEALING:
- When there is low mechanical strain or no motion across the fracture line (e.g. ORIF)
- Occurs when there is rigid fixation
- Minimal callus formation

SECONDARY BONE HEALING:
- When there is higher mechanical strain across the fracture line
- Occurs with non-rigid fixation
- More callus formation present to help stabilize site of fracture
- Greater risk of malunion/non-union
- Inability to form a stable callus can also result in a pseudorthrosis (fibrous non-union)

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4
Q

Describe the stages of secondary bone healing. 4

A
  1. Hematoma formation
  2. Fibrocartilaginous callus formation (chondroblasts lay down a collagen rich cartilaginous matrix) - 10-20 days
  3. Bony callus formation (cartilaginous callus undergoes endochondral ossification; differentiation occurs to chondroclasts + osteoblasts; this replaces cartilaginous callus with bony callus) - 20-30 days
  4. Bone Remodelling - 60-90 days

Kevan Page 1

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5
Q

What is the Axhausen two phase theory of osteogenesis?

A

Phase I:
- Initial bone formation comes from surviving transplanted cells, lays down osteoid randomly
- Lasts 4 weeks, determines final size of graft

Phase II:
- Replaces, reorganizes and remodeling of phase I bone
- Last from 2 weeks to 6 months, peak at 6 weeks
- Pluripotent host cells transformed into osteoblastic cells, bone morphogenic protein important for fibroblast ingrowth

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6
Q

What are the risk factors for mandibular non-union? 2

A
  1. Motion at fracture site
  2. Infected tooth
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7
Q

What are the benefits of rigid fixation? 3

A
  1. Minimal callus development (more callus = cosmetically deforming)
  2. Minimizes infection
  3. Allows immediate function (possibly avoiding the need for MMF)
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8
Q

What is Wolff’s Law?

A

Wolff’s Law = Bone will remodel according to the forces acting upon it (form matches function)
- Poses challenges in the craniofacial skeleton, as force based independent healing may impair aesthetics and occlusion
- Hence, fracture healing is guided by reconstruction

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9
Q

Describe the components of the mandible 8

A
  1. Symphysis
  2. Parasymphysis
  3. Body
  4. Alveolus
  5. Angle
  6. Ramus
  7. Condyle
  8. Coronoid process
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10
Q

List the depressors (5) and elevators (4) of the mandible

A

DEPRESSORS:
1. Geniohyoid
2. Mylohyoid
3. Anterior digastric
4. Platysma
5. Lateral pterygoid

ELEVATORS:
1. Masseter
2. Temporalis
3. Medial pterygoid
4. Lateral pterygoid (superior belly)

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11
Q

What are the 3 areas of inherent mandibular weakness?

A
  1. Condylar neck
  2. Angle - 3rd molar region (deepest roots of teeth at the mandibular angle)
  3. Parasymphysis - at Mental foramen
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12
Q

What are the most common sites for a mandibular fracture?

A
  1. Condyle (30%)
  2. Angle (25%)
  3. Parasymphysis
  4. Subcondylar fracture = fractures of the condyle that do not involve the TMJ

similar to sites of inherent weakness

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13
Q

What should you look for if you find one mandibular fracture?

A

Another mandibular fracture!
- 50% bilateral
- 40% ≥2 fractures
- 50% other associated injuries

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14
Q

How are mandibular fractures classified by site? 7

A
  1. Symphyseal/parasymphyseal (between canines)
  2. Body (between canine and anterior attachment of masseter)
  3. Angle
  4. Ramus
  5. Coronoid process
  6. Condyle
  7. Alveolar process
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15
Q

Regarding mandibular fractures, discuss:
1. Incidence
2. Fracture patterns 3
3. Descriptors 5
4. Imaging findings - what are the options for imaging? 4
5. History and physical examination
6. Management 3

A

INCIDENCE:
- Second most common maxillofacial injury after nasal fractures
- 50% unilateral / 50% bilateral
- 50% more than 1 fracture line (40% ≥2 fractures)
- 50% have associated injuries (other maxillofacial injuries, C-spine)

FRACTURE PATTERNS:
1. Single fracture site: e.g. Condyle
2. Unilateral combination: e.g. Angle + parasymphysis
3. Bilateral combinations:
- Parasymphysis + contralateral angle = parasymphysis punch (MOST COMMON COMBO)
- Body + contralateral angle = body punch
- Bilateral condylar fracture +/- symphysis = direct punch to chin (anterior force)

DESCRIPTORS:
1. Open (compound/exposed bone) or closed (simple/intact overlying skin and mucosa)
2. Fracture pattern: As above, or Oblique, transverse, spiral, greenstick, simple or comminuted
3. Displaced or non-displaced
4. Pathologic or non-pathologic
5. Favourable or unfavourable
- Favourable: Muscle tension pulls fracture line together
- Unfavourable: Muscle tension pulls fracture line apart
- Favourability can be assesesd in both a vertical and horizontal plane (vertically favourable, horizontally favourable, etc.)

IMAGING:
- Mandibular series: AP + PA, lateral x2, Bilateral oblique, Towne + reverse Towne (Towne = angled AP of the skull and visualizes petrous part of pyramids - pt flexes head down; Reverse Towne is same position but beam is coming from behind)
- Panorex
- CT head/neck (99% sensitive)

HISTORY/PHYSICAL EXAM:
- AMPLE history
- ATLS: ABCDE

Physical examination:
- Inspection: SEADS, projection, step deformity
- Oral cavity: Occlusion, trismus, TMJ, Lefort #
- Rhinoscopy: Epistaxis, nasal fracture, signs of CSF leak
- Otoscopy: Battle’s sign, raccoon eyes, hemotympanum, hearing assessment
- Cranial nerve examination

MANAGEMENT:
1. Antibiotics, unless closed fracture outside of occlusion zone (e.g. isolated to lateral mandible ramus/coronoid/condyle)
2. Tetanus prophylaxis
3. Fracture repair - Observation, MMF, ORIF

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16
Q

What makes a mandibular fracture “Favourable”?
Vancouver photos wrong

A

Favourable = Muscle tension pulls fragments back into alignment

Unfavourable = Muscle tension pulls fragments out of alignment
THIS MIGHT BE WRONG IT SHOULD BE THE OPPOSITE
- Horizontal unfavourable: Usually at angle; Vector force of masseter and temporalis muscles pulls fragments apart – if its horizontal favourable, means the vectors are pulling it so its closed horizontally (so think of horizontal as not being able to close it horizontally)
- Vertical unfavourable: Usually body/symph/parasymphysis; Vector force of anterior muscles (mylohyoid, digastric) and pterygoid muscles pulls fragments apart – if vertically favourable, vectors would be pulling it to close it vertically (so think of vertical as not being able to close vertically)

Counterintuitive appearance of the muscles

Depends on orientation of fracture relative to mandibular muscles

Kevan Trauma Pg 3
Kevan Gen # 30
Vancouver 329

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17
Q

What are the 7 considerations for when repairing a mandible fracture?

A
  1. Occlusion
  2. Nutrition
  3. Fracture location and orientation (favourable vs. unfavourable)
  4. Number of fractures
  5. Degree of comminution
  6. Degree of displacement
  7. Bone stock
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18
Q

When are antibiotics indicated for a mandibular fracture? 2

A
  1. Any open fracture
  2. Any fracture of the tooth-bearing mandible: symphysis, parasymphysis, body, alveolar ridge
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19
Q

Discuss the classification of the face (upper third, middle third, lower third) wrt fractures

A
  1. Upper third: Frontal bones
  2. Middle third: Maxillae, zygomas, orbit, nose, naso-ethmoid complex (i.e. mid face)
  3. Lower third: Mandible
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20
Q

Define the following terms with respect to dental positioning:
1. Mesial
2. Distal
3. Buccal
4. Lingual

A
  1. Mesial: Toward the incisors
  2. Distal: Towards the posterior mandible or maxilla
  3. Buccal: Towards the cheek
  4. Lingual: Towards the tongue
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21
Q

Discuss the Angle classification of occlusion.
What is maximum intercuspation?

A
  • Defined by the relationship of the mesiobuccal cusp of the maxillary first molar with respect to the buccal groover of the mandibular first molar

Occlusion Classification (Angle):
1. Class 1: Mesiobuccal cusp of maxillary first molar sits in buccal groover of mandibular first molar
2. Class 2: Mesiobuccal cusp of maxillar first molar sits in front of the buccal groove of mandibular first molar (retrognathia)
3. Class 3: Mesiobuccal cusp of maxillary first molar sits behind buccal groover of mandibular first molar (prognathia)

Maximal Intercuspation: The occlusion position of the mandible in which the cusps fully interpose. The goal of reduction.

Kevan Trauma Page 3

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22
Q

Define Overbite vs. Overjet. What is normal

A

Overbite: Vertical overlap of the maxillary incisors over the mandibular incisors (incisors crossing)

Overjet: Horizontal extension of the maxillary incisors in front of the mandibular incisors
(think of the people with big teeth where their maxillary incisors stick out; horizontally extending beyond the mandibular incisors)

Normal to have an overbite and an overjet measured in mm. These terms are called “normal overbite” and “normal overjet”. Typically 1-3mm

23
Q

Describe the features and signs of a unilateral condylar neck (“subcondylar”) fracture (4)

A
  1. Contralateral anterior open bite deformity
  2. Ipsilateral premature contact of molars
  3. Ipsilateral loss of functional height (shortening) of ramus
  4. Ipsilateral jaw deviation

Kevan Trauma Pg 4

24
Q

Describe the features of a bilateral condylar (“subcondylar”) neck fracture (3)

A
  1. Symmetric anterior open bite (due to the loss of vertical height of the posterior mandible)
  2. Bilateral shortened vertical rami
  3. Bilateral premature contact of the posterior molars
25
Q

Describe the classification system for condylar fractures

A
  1. TYPE 1: MINIMAL DISPLACEMENT
    - Fracture through condylar neck with only slight deviation (maximum 45deg angulation), no displacement
  2. TYPE 2: DEVIATED
    - Angulated minimum 45deg to 90 deg
    - Tearing of medial joint capsule
  3. TYPE 3: DISPLACED
    - Fracture fragments not in contact
    - Condylar head is OUTSIDE capsule (medial and forward)
  4. TYPE 4: DEVIATED + DISLOCATED
    - Condylar head angulated and displaced anterior to articular eminence
  5. TYPE 5: DISPLACED + DISLOCATED
    - Vertical or oblique fracture through condylar head
    - NO contact

Kevan Gen #31 image

26
Q

Regarding the management of mandibular fractures, discuss:
1. What are the treatment options? List them and their approaches 3
2. What are the treatment considerations about the fractures? 4
3. What approach would you use for the following: (a) if occlusion is off, (b) normal occlusion, simple fracture, non-displaced, favourable, (c) Multiple fractures, (d) comminuted fractures
4. When would you give antibiotics? 2
5. What are the indications to remove a tooth? 3

A

TREATMENT OPTIONS:
1. Conservative (observation, soft diet)
2. Closed reduction - Maxillomandibular fixation
3. Open reduction - (1) Transoral (2) External approach (e.g. Risdon approach aka. submandibular approach, can be used to approach the mandibular body and angle)

TREATMENT CONSIDERATIONS:
1. Is it open or closed?
2. Simple or comminuted?
3. Non-displaced or displaced?
4. Favourable or unfavourable?

APPROACHES FOR SITUATIONS:
1. If occlusion is off: ORIF
2. Normal occlusion, simple fracture, non-displaced, favourable: Conservative management can be considered (e.g. isolated subcondylar fracture)
3. Multiple fractures: ORIF or MMR
4. Comminuted fractures: MMF preferred

ANTIBIOTICS:
1. Open wound
2. Involving tooth bearing mandible

INDICATIONS FOR TOOTH REMOVAL:
1. Occlusion: Tooth in fracture line interfering with occlusion
2. Infected: Infected tooth within fracture line
3. Fractured: Fractured non-viable tooth with exposed pulp

27
Q

Discuss the general management of mandible fractures from the time of assessment.
What are the different types of plates that can be used, and what are their general indications?

A
  1. ABCDE + C-spine
  2. Antibiotics for any case involving teeth bearing segments, until gingival or mucosa healed
  3. Closed vs. ORIF reduction

RIGID:
1. Load-bearing: plate bears the forces of function at fracture site (therefore used for bad bone where you can’t rely on them to use force)
- Accomplished by locking reconstruction plate
- For edentulous fractures, comminuted fractures, missing piece of bone, reconstruction with flap/graft

  1. Load-sharing (semi-rigid): stability created by frictional resistance between bone ends and the hardware used for fixation
    - Lag screws, miniplate
    - For simple fractures with acceptable amount of bone stock

NON-RIGID (Interosseous wiring)
- ORIF should be done ASAP
- If > 3 days = MMF and IV antibiotics
- Rigid and semirigid techniques obviate the need for MMF
- External fixation (rarely used) - when there is a bone gap, contaminated GSW, or infection

Vancouver 330

28
Q

Describe the Kazanjian & Converse Classification for mandibular fractures and dentition? Significance?

A
  1. CLASS 1: Teeth present on both sides of the fracture line
  2. CLASS 2: Teeth present only on one side of the fracture line
  3. CLASS 3: Patient is edentulous (no teeth on bony fragments)

Clinical significance: Determines ability to use arch bars for MMF

Vancouver 329

29
Q

What are the two forces acting on the mandible in the angle and body?
How does this affect how you manage the mandible fracture?

A

1) COMPRESSION FORCE
- Lower border of mandible
- Pushes segments together
- Need rigid load bearing plate

2) TENSION STRESS
- Upper border of mandible
- Causes distraction and separation
- Need thinner monocortical miniplate or leave arch bars in place

Vancouver 330

30
Q

Discuss indications for MMF 4 vs. ORIF for Condylar fractures 10 5/5

A

MMF INDICATIONS:
1. Split condylar head
2. Intracapsular fracture
3. Small fragments from comminuted condyle
4. Risk of devascularization of the condylar segment with ORIF
Essentially anything that involves the articular surface

“SIRS”

ORIF INDICATIONS:

ABSOLUTE (Zide and Kent):
1. Foreign body in joint space (e.g. gunshot wound)
2. Displacement into middle cranial fossa
3. Inability to achieve occlusion with closed reduction after 1 week
4. Open fracture with potential for fibrosis
5. Lateral extracapsular deviation of condyle

“FILMO” - FB, inability to occlude > 1 week, lateral displacement, MCF displacement, open fracture

RELATIVE:
1. Associated with midface (comminuted) fractures
2. Medically compromised or cognitively impaired patients with displaced fracture / open bite or retrusion
3. Displaced fracture with edentulous or partially edentulous mandible (cannot do MMF)
4. Comminuted symphysis and condyle fracture with loss of teeth
5. Bilateral condylar fractures associated with marked pre-injury malocclusion (gnathologic problem)

31
Q

What are the 8 indications, 8 contraindications, and 10 complications for closed reduction with MMF of non-condylar mandible fractures?

A

INDICATIONS:
1. Contraindications to ORIF (ie. Gross infection, Healing problems, Severe comminution, Pediatric patient)
2. Grossly comminuted fractures (ie. can’t plate)
3. Pediatric fractures (ORIF can injure tooth buds, erupting teeth)
4. No soft tissue covering (can’t achieve closed plate coverate)
5. Non-displaced favourable fractures
6. Atrophic edentulous mandible, if dentures/splints available (insufficient bone height to plate) - e.g. gunning splints
7. Stable coronoid fracture
8. Certain condylar fractures
“Can’t Commit, Promised to See NF Every Saturday, he’s Crowned a Conman”

CONTRAINDICATIONS (essentially, contraindications to having mouth wired shut due to increased risk of aspiration):
1. Unfavourable fractures
2. Medically compromised:
- Alcoholics
- Seizure disorder
- Cognitive impairment / psychiatric disorder
- Nutritional concerns
- Respiratory disease (COPD) or poor resp status

CAPRISUN:
- COPD/Asthma
- Alcoholics
- Psychiatric instability
- Retardation (cognitively unsound)
- Inability to eat (nutritional concerns)
- Seizure disorder
- Unfavourable fracture
- Nausea (chronic); not compliant

COMPLICATIONS:
1. Aspiration
2. Airway obstruction
3. Weight loss, nutritional deficit
4. TMJ ankylosis or dysfunction
5. Dental injury
6. Malocclusion
7. Malunion
8. Non-union
9. Infection
10. Trismus
11. Poor cosmetic outcome

32
Q

What are the 7 indications, 5 contraindications, and 7 complications for ORIF (open reduction, internal fixation) of non-condylar mandible fractures?

A

INDICATIONS:
1. Displaced fracture
2. Unfavourable fractures
3. Panfacial fractures (required as basis for reconstruction)
4. Comminuted (but plate-able)
5. Severely atrophic edentulous mandible (no osteogenic potential to heal on own)
6. Some condylar fractures
7. Medically compromised patients
- Alcoholics
- Seizure disorders
- Cognitive impairment
- Nutritional concerns
- Respiratory disease (COPD) and poor pulmonary reserve
- Elderly

SUMOSA
Stable base needed for reconstruction (ie. panfacial fractures)
Unfavourable and unstabls
Medically can’t do MMF (CAPRISUN)
Obviously displaced
Obviously unstable, Obviously comminuted (but plateable)
Some condylar fractures
Atrophic (severely) edentulous mandible with no osteogenic potential to heal on own

CONTRAINDICATIONS:
1. Gross infection or wound contamination
2. Healing problems (radiation history is a big issue, transplant, steroids)
3. Severe comminution (unable to plate, better to do MMF)
4. Pediatric patient
5. No soft tissue to cover defect

“CHIN”
Comminuted, child
Healing problems
Infected (gross)
No soft tissue to cover defect

COMPLICATIONS:
1. Nerve injury: Mental, inferior alveolar, marginal mandibular
2. Hardware infection
3. Malunion
4. Non-union
5. Malocclusion
6. Hardware exposure
7. Mandible fracture (while drilling)

33
Q

What are the options for MMF? 6

A
  1. Erich arch bars
  2. MMF screws
  3. Bridle wire
  4. Ivy loops
  5. Acrylic splints (useful in children with deciduous/mixed dentition)
  6. Risdon cables (twisted cable is substituted for an arch bar + circumdental wiring)
34
Q

What is the duration of fixation for MMF?

A
  • Children: 3-4 weeks
  • Adults: 4-6 weeks
  • Elderly: 6-8 weeks
  • Condylar fractures: 2-4 weeks
  • Body and angle fractures: 4-6 weeks
35
Q

List the possible approaches for open reduction of a mandibular fracture. 2 adv disadvantage for each

A

INTRAORAL:
1. Labial sulcus incision: symphysis and parasymphysis
2. Vestibular incision: body, angle, ramus

Advantages:
- Avoids scar and marginal mandibular nerve injury
- Faster
- Can reach all areas of mandible (angle and symphyseal & parasymphysis)

TRANSCUTANEOUS:
1. Use of existing lacerations
2. Submental
3. Submandibular (Risdon approach)
4. Retromandibular (Hind’s approach)
5. Preauricular
6. Facelift (rhytidectomy) approach)

Advantages:
- Better visualization of higher fractures and comminuted fractures

Disadvantages:
- Adds scar
- RIsk of marginal mandibular injury

36
Q

What are the techniques on how to perform a mandible ORIF?

A

Rigid fixation:
- Reconstruction plate with 3 screws on each side of the fracture
- Large compression plates
- 2 lag screws across fracture (screw it so that two bone segments can compress together)
- Use of 2 plates over fracture site
- 1 plate and 1 lag screw across fracture site

37
Q

What are the benefits of rigid fixation of mandibular fracture? 5

A
  1. Increases stability across fracture line (Increases likelihood of primary vs. secondary bone healing, decreases callus formation, decreases risk of malunion/non-union)
  2. Immediately functional
  3. Reduces infection risk
38
Q

What are 10 reasons for malocclusion following mandibular fracture repair

A
  1. Poor alignment (surgical)
  2. Malunion
  3. Non-union
  4. Unfavourable fracture
  5. TMJ subluxation / condyle subluxation
  6. TMJ ankylosis
  7. Undiagnosed second fracture of mandible or maxilla
  8. Tooth impaction in fracture line
  9. Osteomyelitis
  10. Delayed union - lack of mineralization at 8-12 months

“NOT SUMO”
Non-union or delayed union
Osteomyelitis
Tooth impaction in fracture line
Subluxation or ankylosis of the TMJ or condyle subluxation
Undiagnosed second fracture
Malunion
Obviously bad surgical alignment or bad fracture

39
Q

What are 3 pitfalls of oral vestibular sulcus incisions for mandibular ORIF?

A
  1. Damage to mental nerve
  2. Failure of water tight closure
  3. Failure to resuspend mentalis
40
Q

Describe the Pruzansky-Kaban’s classification of mandibular hypoplasia / hemifacial microsomia

A
  1. TYPE 1: Smaller than preserved normal side. Otherwise normal features
  2. TYPE 2: Condyle, ramus, sigmoid notch identifiable but grossly distorted
    - 2A: Short abnormal ramus. Glenoid fossa in satisfactory position
    - 2B: TMJ displaced anteromedially and inferiorly
  3. TYPE 3: Absent TMJ, ramus, condyle

Kevan Trauma Pg 7

41
Q

What are the possible complications of maxillofacial surgery? 10

A
  1. Inadequate reduction
  2. Malocclusion
  3. Malunion
  4. Non-union
  5. Osteomyelitis
  6. Pseudoarthrosis
  7. Ocular injury
  8. Intracranial injury
  9. Neurovascular injury
  10. Facial asymmetry (adverse cosmesis)
42
Q

Describe the horizontal and vertical buttresses of the mid-face

A

BUTTRESSES: Describes the relatively stronger areas of the midface skeleton that transmit forces to the skull base

VERTICAL BUTTRESSES: 7 total, 3 paired, 1 unpaired

Paired Buttresses:
A. Nasomaxillary (NM) = Medial
- Travels from the maxillary alveolus along the nasal and lacrimal bones to the frontal bone

B. Zygomaticomaxillary (ZM) = Lateral
- Travels from lateral maxillary alveolus to the malar eminence of the zygoma, then along lateral orbital rim to frontal bone
- Greatest occlusal load

C. Pterygomaxillary = Posterior
- Travels from the maxilla to the pterygoid plates of the sphenoid

Unpaired Buttress:
A. Midline buttress (Frontoethmoid-vomerine)
- Compromised of vomer, perpendicular plate of the ethmoid bone
- Connects the maxillary crest to the frontal bone

HORIZONTAL BUTTRESSES: 3 major
1. Frontal bar (Superior orbital rim + frontal bone)
2. Inferior orbital rims + Zygomatic arch
3. Alveolar process of maxilla
4. Mandible (but not part of mid-face)

Kevan Trauma Pg 8
Vancouver 332

43
Q

What is the normal intercanthal distance? What distance suggests telecanthus?

A

Normal = Approximately 30mm

Telecanthus = >45mm

44
Q

What are the essential elements of a facial trauma history and examination?

A

HISTORY: AMPLE + Tetanus
1. A: Allergies
2. M: Medications
3. P: Past medical history
4. L: Last meal (when)
5. E: Events leading up to incident
6. Tetatnus status

PHYSICAL EXAMINATION
1. ABCDE (including C-spine)
2. Inspection:
- SEADS: Swelling, erythema, atrophy, deformity, scars
- Projection
- Bruising/ecchymosis (battle’s sign, raccoon eyes)
- Facial asymmetry

  1. Intraoral examination:
    - Occlusion
    - Maxillary mobility (assess for Lefort fracture)
    - Assess for open bite deformity (posterior teeth occluded but not anterior)
  2. Anterior Rhinoscopy:
    - Assess for nasal fracture
    - Assess for septal hematoma
    - Assess for epistaxis
    - Assess for signs of CSF leak
  3. Otoscopy
    - Hemotympanum
  4. Cranial nerve examination
    - Visual acuity
    - RAPD
    - Extraocular movements (Especially assess for inferior rectus entrapment)
    - Facial nerve function
    - Hearing testing including tuning fork assessment

https://www.researchgate.net/profile/Yadranko-Ducic/publication/282420956/figure/fig3/AS:391509347192836@1470354510789/Classic-anterior-open-bite-deformity-on-patient-with-subcondylar-fracture.png

45
Q

How do you clear a C-spine? (Ottawa C-Spine Rules)

A

(1) IMMEDIATE INDICATIONS FOR IMAGING:
1. Age ≥ 65
2. Dangerous mechanism
3. Paresthesias in extremities

Dangerous mechanisms:
1. Fall ≥ 3 feet or 5 stairs
2. Axial load to head (E.g. diving)
3. High speed MVC (>100km/hr), rollover, ejection
4. Motorized recreational vehicles
5. Bicycle struck or collisiion

(2) If no immediate indications, then identify any low-risk factors which allows safe assessment of range of motion (just need ONE of the following to move to number 3; if NONE, then radiograph)
1. Simple rear-end MVC (DOES NOT INCLUDE: Pushed into oncoming traffic, hit by bus or large truck, rollover, hit by high speed vehicle)
2. Sitting position in ED
3. Ambulatory at any time
4. Delayed onset of neck pain (not immediate)
5. Absence of midline c-spine tenderness

(3) Able to actively rotate neck 45 degrees left and right?
- Yes = No radiography
- Unable = Radiography

RULE NOT APPLICABLE IF:
1. Non-trauma cases
2. GCS < 15
3. Unstable vital signs
4. Age < 16 years
5. Acute paralysis
6. Known vertebral disease
7. Previous C-spine surgery
8. Pregnant

46
Q

Describe the LeFort fracture classification system

A
  1. LeFORT 1:
    - Floating palate
    - Fracture line extends across maxillary alveolus
    - Involves nasal septum, laterally and posteriorly through all maxillary walls to pterygoid plate
  2. LeFORT 2:
    - Floating maxilla
    - Fracture line disrupts the nasomaxillary buttress
    - Fracture line travels through alveolar ridge, lateral nasal wall, and orbital rim
    - Involves nasofrontal suture, frontal process of maxilla, lamina papyracea, inferior orbital rim and foramen, anterior and posterior maxillary wall, zygomaxillary suture, pterygoid plate, high septum
  3. LeFORT 3:
    - Floating face
    - Fracture line separates the cranium from the facial skeleton
    - Fracture line travels through the zygoma, orbital, nasofrontal suture

Kevan Trauma Pg 9

47
Q

What are the goals and principles of surgical repair for facial fractures? 7

A

Structure-Function-Cosmesis

STRUCTURE:
1. Re-establish stability

FUNCTION:
1. Re-store occlusion
2. Address diplopia or enopthalmos
3. Avoid contracture

COSMESIS:
1. Restore projection
2. Restore symmetry
3. Minimize cutaneous cuts

48
Q

What are the goals and principles of mandibular reconstruction? Name 6

A

Structure-Function-Cosmesis

STRUCTURE:
1. Orocutaneous closure
2. Mandibular continuity
3. Occlusion
4. TMJ integrity

FUNCTION:
1. Articulation
2. Mastication
3. Oral competence
4. Restore/maintain sensation

COSMESIS:
1. Restore projection
2. Height
3. Width
4. Symmetry
5. Contour

49
Q

What are the goals and principles of maxillary reconstruction?

A

Structure-Function-Cosmesis

STRUCTURE:
1. Oronasal closure
2. Orbital support
3. Nasolacrimal patency
4. Occlusion

FUNCTION:
1. Velopharyngeal insufficiency
2. Articulation
3. Swallowing
4. Sensation

COSMESIS:
1. Projection
2. Height
3. Width
4. Symmetry
5. Contour

50
Q

First step/goal in repairing any facial fractures?

A

Restore occlusion

51
Q

How do you immobilize distraction of a facial fracture? How do you immobilize rotation of a facial fracture?

A

Immobilize distraction: 2 point fixation

Immobilize rotation: 4 point fixation

52
Q

Describe the general management of LeFort fractures?

A

Goals:
1. Restore vertical height
2. Restore facial width
3. Improve projection

MANAGEMENT:
1. ABCs
2. Antibiotics
3. Tetanus
4. Reduce fracture (Rowe forceps)
5. MMF
6. Expose fracture site via multiple approaches
7. Plate fractures
8. Release MMF
9. Check occlusion
10. Elastics/replace MMF
11. If minimal displacement, minor malocclusion or poor surgical candidate –> MMF otherwise ORIF

53
Q

In a case of panfacial smash, what order do you fix things in? 5

A
  1. Occlusion
  2. Mandible
  3. Zygoma
  4. Palate
  5. Maxilla

First occlude
Then the “outsides first, down to up” mandible then zygoma
Then the “insides, down to up” palate then maxilla

Skull base can be used as the ultimate reference if the face is completely smashed

54
Q

Discuss the approach to CT evaluation of facial fractures 5

A
  1. Vertical and horizontal buttresses
  2. Zygomatic arches
  3. Orbital walls
  4. Palate
  5. Mandible

Top down plus buttresses

Facial Plastics & Trauma (9 decks)

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