7. Maxillofacial Trauma Flashcards
(116 cards)
1
Q
Glasgow Coma Scale
A
Objective measure of patient’s neurological status and used serially to track clinical progress.
Patients >5yo
Score 8 or less, early airway protection is encouraged
Minimum score is 3
Eye Opening
1 no response
2 to pain only
3 to verbal stimuli, command, speech
4 spontaneous opening with blinking
Verbal Response
1 no response
2 incomprehensible
3 inappropriate words
4 confused conversation but able to answer
5 oriented
Motor Response
1 no response
2 extension in response (decerebrate posturing)
3 flexion in response (decorticate posturing)
4 withdraws in response to pain
5 purposeful movement to pain
6 obeys commands for movement
2
Q
What are the classes of hemorrhagic shock and how much blood loss can be expected with each?
A
1 <750
2 750-1500
3 1500-2000
4 >2000
3
Q
Severity of head injury based on GCS
A
Severe head injury/coma GCS 8 or less
Moderate head injury GCS 9-12
Mild head injury GCS 13-15
Denotation of “T” after the score is applied to intubated patient
4
Q
Describe the zones of the neck for penetrating trauma
A
Zone 1: thoracic inlet to cricoid cartilage
Zone 2: cricoid cartilage to angle of the mandible
Zone 3: angle of the mandible to base of skull
5
Q
Define load bearing vs. load sharing
A
Load bearing is hardware of sufficient strength to bear the entire load
-Plates and screws immobilize fractured segments. Thicker, rigid plates with bicortical screws or lag screws. 3 screws on each segment.
Load sharing is unable to bear all functional load across fracture
- Miniplates and monocortical screws along lines of osteosynthesis as described by Champy
6
Q
What is the ideal line of osteosynthesis of the mandible?
A
Described by Maxime Champy 1976: a line around the mandible where plating the tension and compression forces are balanced, thus offering the best biomechanical advantage for positioning of plates and screws
7
Q
Non-locking plates/screws
A
Plates must be adapted intimately to the bone. Compression of the plate onto the bone may cause bone resorption under the plate.
8
Q
Locking plates/screws
A
Screws lock into the plate while it is being tightened. Does not require a perfect adaptation of the plate to the bone. Plate bears the load of mechanical forces.
9
Q
General approach to facial trauma patient
A
Mechanism of injury, LOC
Confirm ATLS/PALS has been performed w/ appropriate consultations
C spine evaluation and clearance
Physical exam: GCS
Facial asymmetry, lacerations
Cranial nerve exam II-XII
Paresthesias V1, V2, V3
Ocular movements, pupillary reaction, diplopia, intraocular pressure, proptosis, dystopia, enophthalmos, periorbital ecchymosis, telecanthus
Ecchymosis behind ears (Battle’s sign), otorrhea, eval tympanic membrane
Midface loss of projection, edema, step deformities
Nose for asymmetry, septal hematoma, bleeding
Jaws for range deviations on opening, step deformities, hematoma, intraoral lacerations
10
Q
Muscle action classification for mandible fractures
A
Vertically favorable = resistance to medial pull
Horizontally favorable = resistance to upward movement
11
Q
Contraindications for closed reduction of the mandible
A
Alcoholics, seizure disorders, mental retardation, nutritional concerns, respiratory diseases (COPD), unfavorable fractures
12
Q
Considerations for edentulous mandible fractures
A
Decreased bone height, decreased buttressing effect
Significant effect of muscular pull (digastrics)
Biological differences = dependent on periosteal (centripetal) blood flow. Delayed healing, decreased ability to heal with age
Tx: circummandibular wires fixated to piriform rims and circum zygomatic wires with patient’s denture or Gunning style splints. Requires IMF with longer periods due to age.
Open reduction >20mm mandible treated as dentate mandible. Load bearing plates. Bone grafts commonly incorporated.
13
Q
Indications for open reduction of condylar fractures
A
Zide’s absolute indications:
1. middle cranial fossa involvement with disability
2. inability to achieve occlusion with closed reduction
3. invasion of joint space by foreign body
4. lateral capsule violation and displacement
Zide’s relative indications:
1. bilateral condylar fractures where vertical facial height needs to be restored
2. associated injuries that dictate early or immediate function
3. medical conditions that indicate open procedures
4. delayed treatment with misalignment of segments
14
Q
When to remove teeth in the line of fracture
A
- Gross mobility
- Periapical pathology
- Preventing reduction
- Roots with a fracture
- Exposed root
- Delay in repair from time of fracture
- Recurrent infection at fracture site despite antibiotic therapy
15
Q
LeFort classifications
A
LeFort I: horizontal fracture above apices of maxillary dentition across nasal septum and maxillary sinuses. Posteriorly extends through pyramidal process of palatine bone and pterygoid processes of sphenoid bone. May also involve fracture of the palate.
LeFort II: pyramidal fracture extends from nasofrontal region down through medial orbital wall, drossing infraorbital rim and zygomatic buttresses. Posteriorly similar to LF1.
LeFort III: complete craniofacial disjunction with fracture lines through nasofrontal junction, zygomaticofrontal articulations, zygomaticomaxillary suture, temporozygomatic suture, pterygomaxillary junction, medial and lateral orbital walls, and superior articulation of nasal septum.
Usually mixed combination.
16
Q
Four key areas to evaluate for LeFort fractures on CT
A
- Pterygoid plates (strong indication of LeFort fracture)
- Lateral margin of nasal fossa (LeFort I)
- Inferior orbital rim (LeFort II)
- Zygomatic arch (LeFort III)
17
Q
Principles of LeFort fracture management
A
-Non-displaced fractures without clinical compromise = soft diet with observation & soft diet or 4-6 weeks IMF
- Edentulous patients open treatment or observation
Treat as soon as possible. Longer open or compound fractures are untreated, greater incidence of infection and malunion.
- Fixate fractures to allow immobilization and optimal healing
- Use buttresses for fixation
- Restore preoperative occlusion
- Ensure to treat nasal complex and orbital fractures as indicated
18
Q
Four articulations of the zygoma
Where is the weakest portion of the zygomatic arch?
A
- frontozygomatic
- zygomaticomaxillary
- zygomaticosphenoid
- zygomaticotemporal
Weakest portion of the zygomatic arch is not the zygomaticotemporal suture, but a point 1.5cm posterior to this.
19
Q
Recommended sequence of fixation for ZMC fractures
A
- Fixate frontozygomatic region first to restore facial height of the complex
- Fixate zygomaticomaxillary buttress region to restore facial projection and ensure that the medially rotated body is back in its normal anatomical position
- Fixate the orbital rim to define orbital volume and facial volume
- Orbital floor should be managed last as it is critical that the aforementioned sites are placed back into alignment to prevent enophthalmos and facial widening
Alignment of the sphenozygomatic suture is a good indicator of the three-dimensional position of the zygoma.
20
Q
Bones of the orbit
- Orbital roof (2 bones)
- Lateral wall (2 bones)
- Orbital floor (3 bones)
- Medial wall (4 bones)
A
Orbital roof: frontal and lesser wings of sphenoid
Lateral wall: greater wing of sphenoid and zygomatic bone
Orbital floor: maxillary bone, zygomatic bone, and palatine bone
Medial wall: frontal process of maxillary, ethmoid (lamina papyracea), lacrimal, and sphenoid bones
21
Q
Contents of the superior orbital fissure
A
CN III, IV, VI
Sensory nerve V1
Sympathetic fibers
Superior ophthalmic vein
Recurrent and middle meningeal artery
Separates greater and lesser wings of sphenoid
Delineates between orbital roof and lateral orbital wall
22
Q
Contents of the inferior orbital fissure
A
Sensory nerve V2, parasympathetic branch of the pterygopalatine ganglion, and inferior ophthalmic vein
23
Q
Contents of the optic canal
A
Optic nerve, ophthalmic artery, sympathetic fibers
24
Q
Whitnall’s tubercle
A
10mm below FZ suture and 3-4mm inside the lateral orbital rim.
Attachments: (1) lateral horn of levator aponeurosis, (2) lateral canthal tendon of the eyelids, (3) Lockwood’s ligament, (4) check ligaments
All four of these comprise the lateral retinaculum
25
Annulus of Zinn
Tendinous ring of fibrous tissue at apex of the orbit surrounding the optic nerve that is the origin of the rectus muscles of the eye.
26
Describe the measurements for safe dissection in the orbit
All measurements from intact anterior lacrimal crest. Anterior ethmoidal foramen 24mm, posterior ethmoidal foramen 36mm, optic foramen 42mm
27
Layers of the lid
Skin, subcutaneous tissue, orbicularis oculi, septum, tarsal plate, conjunctiva
28
Normal ocular pressures with tonometry pen
10-20mmHg
29
Indications for orbital fracture repair
-Large orbital fractures >50% of orbital floor; enophthalmos >2mm, diplopia in primary gaze
-Asymptomatic patients without the aforementioned signs and symptoms-observation
-Muscle incarceration is a true emergency as entrapped tissue will become ischemic
-Signs of oculocardiac reflex require emergent surgical intervention
-Most fractures can be observed for 2 weeks for resolution of motility disturbance resulting from edema, hemorrhage, or rectus muscle contusion
Antibiotics (sinus coverage), sinus precautions, nasal decongestants, ice packs, HOB elevation
30
Describe your technique for a transconjunctival approach
- Corneal shield with ophthalmic-grade bacitracin/ocular lubricant placed on globe
- Local w/ vasoconstrictor under conjunctiva as well as around lateral canthus if lateral canthotomy is planned
- 15 blade sharp incision through lateral canthus. Tip of iris scissor inside palpebral fissure, extending laterally to depth of underlying lateral orbital rim (do not exceed 7mm laterally to ensure safe distance from temporal branch of facial nerve). Scissors used to cut horizontally through lateral palpebral fissure (skin, orbicularis muscle, orbital septum, lateral canthal tendon, and conjunctiva)
- Using lateral orbital rim as a stop, inferior cantholysis is performed by turning the orientation of the scissors vertically to incise the inferior canthal ligament.
- Conjunctiva is approached using blunt tipped pointed scissors to dissect through the small incision through the conjunctiva made during lateral canthotomy. Bluntly undermine conjunctiva over the orbital septum and extend as far medially (3mm away from caruncle).
- Incise conjunctiva below curvature of tarsal plate
- Palpate inferior orbital rim. Retract orbital contents and lower lid and dissect to rim.
- Strip periosteum over orbital rim, anterior surface of maxilla, zygoma, and orbital floor
- Place broad malleable retractor
- Explore orbit, release entrapped tissue, identify bony landings
- Forced duction test
- 4-0 Vicryl to reattach lower limb of lateral canthal tendon
- Subcutaneous sutures and 6-0 skin suture placed along horizontal lateral canthotomy
- Some surgeons reapproximate bulbar conjunctiva with 6-0 fast gut
31
Test for nasolacrimal duct injury
Jones I test: few drops of fluorescence dye or propofol in the lower conjunctival sac, observe for fluorescein/propofol in the nose. If not identified, proceed to Jones II test
Jones II test: irrigate punctum and inject fluorescein into the (SAC) puncta/canaliculi. If fluorescein is seen, then the blockage is above the lacrimal sac; if not, then blockage is near the punctum or canaliculus
32
Dacryocystorhinostomy
Secondary repair of nasolacrimal duct injury - goal to create a bony window between lacrimal sac and nose
33
What is hyphema?
Bleeding from torn vessels at root of iris in anterior chamber.
Positional blurred vision, photophobia.
Graded based on percent of anterior chamber filled/involved
Grade 1: 1/4 of anterior chamber
Grade 2: 1/2
Grade 3: 3/4
Grade 4: complete coverage (blackball or 8-ball hyphema)
Managed with
- atropine 1% ophthalmic drops to dilate pupil, immobilize iris to prevent future bleeding;
- timolol ophthalmic drops (beta-blocker to decrease intraocular pressure)
- acetazolamide PO (carbonic anhydrase inhibitor)
- steroids
- bed rest, HOB elevated
Complications: rebleeding, glaucoma, corneal staining
34
What is a Marcus Gunn pupil?
afferent pupillary defect - swinging flashlight test
35
What is Horner's syndrome?
Injury to sympathetic nerves supplying the globe
TRIAD
(1) miosis (unopposed parasympathetic)
(2) eyelid ptosis (decreased Muller's muscle tone)
(3) anhidrosis (sweat glands)
Dx: 4% cocaine drops to affected eye fails to dilate compared to unaffectted pupil.
36
What is superior orbital fissure syndrome?
Ophthalmoplegia (CN III, IV, VI)
Lid ptosis (CN III)
Mydriasis and loss of direct pupillary light reflex (CN III parasympathetic fibers)
37
What is orbital apex syndrome?
Superior orbital fissure syndrome + injury to CN II (loss of vision and direct and consensual pupillary light reflex).
Superior orbital fissure syndrome
-Ophthalmoplegia (CN III, IV, VI)
-Lid ptosis (CN III)
-Mydriasis (CN III parasympathetic fibers)
38
NOE complex
Nasal bones, frontal process of the maxilla, nasal process of the frontal bone, and medial orbital wall (composed of lacrimal bone and ethmoid bones)
39
Manson and Markowitz Classification
Classification of NOE fracture based on condition of central fragment (frontal process of the maxilla) and medial canthal tendon.
- Type I: no comminution of the central fragment and tendon is intact
- Type II: comminution of the central fragment and the tendon is intact
- Type III: severe comminution of the central fragment and the tendon is avulsed
40
How do you test for CSF leak
- Beta-2 transferrin
- May also send sample for glucose and chloride level
Chloride is usually greater and glucose is less than serum
- Halo test involves placing drop of the bloody rhinorrhea on filter paper and seeing a center of blood and straw-colored halo
41
How are type III NOE fractures treated?
Canthopexy with posterior-superior vector
Transnasal wiring technique: the vector of fixation is posterior and superior to the lacrimal fossa
Suturing the tendon to a miniplate in the NOE region (non-resorbable suture with posterior-superior vector)
Mitek anchoring procedure (use of suture anchoring device for management of medial canthal tendon)
42
Complications of NOE fracture
Dacryocystitis: infection of lacrimal sac due to obstruction. Antibiotics (PCN-based).
Epiphora: attempt lower lid massage. If no improvement, dacryocystorhinostomy
43
How is a dacryocystorhinostomy performed?
Incision 6mm from medial canthal angle, dissect to lacrimal sac. H incision made in nasal soft tissue and lacrimal sac. Posterior flaps sutured together. Puncta intubated with Crawford tube and passed through the openings of the nose. Ends of the Crawford tube are tied and the anterior flaps of the nasal mucosa and lacrimal sac are sutured together. Orbicularis muscle and skin are closed. Stent left in place for 3-6 months.
44
What is Kiesslebach's plexus?
Located along anterior aspect of the septum, the confluence of anterior ethmoidal artery, posterior ethmoidal artery, nasopalatine artery, and septal branch of the superior labial artery.
Most common site of epistaxis
45
Drainage of the frontal sinus
15% have true nasofrontal duct facilitating sinus drainage into middle meatus of the nose.
The remaining population drains via hiatus semilunaris to nasal frontal tract.
46
Gonty's classification of frontal sinus fractures
1. Isolated anterior table
2. Anterior and posterior table
3. Posterior table
4. Comminuted fracture
47
Management of CSF leak (frontal sinus)
Observation 7 days
Neurosurgical management may include placement of lumbar drain to decrease intracranial pressure or direct repair of dural tear if drain is not successful
48
How is the nasofrontal duct involvement assessed and managed during frontal sinus fracture repair?
Test patency intraoperatively by injection of dye (fluorescein, methylene blue, propofol) into duct/tract with a large bore catheter and observation for passage into nasal sill.)
If outflow is compromised or uncertain, sinus obliteration procedure is recommended.
Expose sinus, obliterate entire mucosal surface (to prevent mucocele formation)
Elevate, invert, and place lining of sinus floor back into infundibulum to obstruct the outflow tract.
Pack with local tissue to ensure separation of inverted mucosa from sinus (temporalis fascia, muscle, thin piece of calvarium, or synthetic fibrin sealants.
Obliterate remaining free space with abdominal fat, iliac crest bone, fascia, muscle, or pericranium. (Synthetic materials such as hydroxyapatite, bioglass, gelfoam is less common).
49
When is cranialization considered for frontal sinus fractures?
In the case of large or highly comminuted displaced posterior fracture fragments.
Frontal craniotomy, repair of dura, debridement of damaged brain segment, repair of dural lacerations, removal of posterior wall, removal of mucosal lining of the sinus, and plugging nasofrontal ducts. Pericranial flap is used to separate the sinus from the splanchnocranium. Brain is allowed to fill into the extradural space and the anterior table is reconstructed.
50
Describe the coronal approach
- Local anesthetic
- Incision 5cm behind hairline
- Skin, subcutaneous tissue, galea between temporal lines exposing loose areolar plane. Blunt dissection in all directions, primarily anterior.
- Extension below temporal line carefully completed using subgaleal plane as a guide to bluntly dissect alongside the anterior helix
- Hemostasis with Raney clips
- 2-3 cm superior to the supraorbital rims, pericranium is incised and dissection can proceed in subpericranial plane to obtain exposure
- If additional exposure is needed, superficial temporalis fascia can be excised at the root of the zygomatic arch meeting the horizontal incision above the orbital rims at a 45-degree angle. (temporal branch of facial nerve should be safely located on the undersurface of the temporoparietal fascia.)
- Orbital foramen/notch may be osteotomized to allow release of the neurovascular bundles and further retraction
- Closure in layered fashion to minimize drooping. Temporalis fascia is often suspended to minimize drooping and protect facial nerve.
51
Describe follow-up protocol for frontal sinus fractures
Weekly for 1 month
Every 3 months for first year
Every year up to year 5
CT scans at years 1, 2, 5 or if symptomatic
52
Complications frontal sinus fracture
- Meningitis
- Mucocele, mucopyocele
- Intracranial abscess
- Cavernous sinus thrombosis
- Contour deformity
53
Approach to the panfacial fracture patient
"Known-to-unknown": begin with less comminuted fractures where anatomic reduction can be more easily assessed, and then proceed to more comminuted regions where bridging constructs and bone grafting may be required.
- Bottom-up and inside-out approach
- Top-down and outside-in approach
Do not deviate from method once you choose one!
54
Bottom Up Inside Out approach to panfacial
Use the mandible as the foundation for reconstruction:
(1) MMF
(2) mandibular fractures. Keep pressure at angle to prevent splaying and increased lower facial width
(3) Condylar fractures if indicated to restore vertical height
(4) Treat ZMC next (frontozygomatic region first to restore height, then zygomaticomaxillary buttress to restore projection, then fixate orbital rim to define orbital volume and facial volume. Orbital floor last).
(5) NOE complex
(6) Frontal sinus
(7) Implants/augmentation (dorsal struts)
(8) Soft tissue support/repair
55
Top-Down, Outside Approach to panfacial fractures
Some authors choose this approach after restoring occlusion
(1) frontal sinus/supraorbital rims
(2) ZMC
(3) NOE
(4) Maxillary/palatal/LeFort
(5) MMF
(6) Subcondylar
(7) Mandibular bony/ramus/angle/symphysis
(8) Implants/augmentation
(9) Soft tissue support/repair
56
Key landmarks for reduction of panfacial fractures
Dental arches, mandible, sphenozygomatic suture, intercanthal region
57
What is the protocol for tetanus prophylaxis?
Tetanus prophylaxis should be evaluated for contaminated wounds.
If the patient has not been administered vaccination over 10 years, failed to complete a primary tetanus vaccination of at least 3 doses, or has an unclean wound and has not received tetanus vaccination in over 5 years (booster dose 0.5ml intramuscular)
If no history of immunization or uncertain, passive immunity with human tetanus immune globulin should be administered (250 U intramuscular single dose).
58
Pulsatile irrigation of wounds requires ___PSI to remove adherent bacteria with a balanced salt solution
7psi
59
Bacteria in dog and feline bites
pasteurella multocida
streptococci
staphylococcus aureus
60
Bacteria in human bites
Eikenella corrodens
Staphylococcus aureus
Haemophilus influenzae
Corynebacterium
(also consider hepatitis B, C, herpes simplex, syphilis, TB, and HIV which can be transmissible through human bites)
61
Antibiotic coverage for animal bites
Augmentin
if penicillin allergic, consider doxycycline and metronidazole
62
Describe the course of Stenson's duct
Site A: Proximal - intraglandular
Site B: superficial to masseter
Site C: anterior to masseter and subsequently enters the buccinators. Terminates adjacent to second molars
63
Treatment of sialocele
Check to ensure saliva (amylase levels >10,000 u/l)
- Pressure dressing
- Multiple aspirations with or without antisialogogues (propantheline 15mg PO QID 30 mins before meals), octreotide, parasympathetic denervation (tympanic neurectomy), secondary duct repair, intraoral fistula creation (dochoplasty), low radiation (1800 rad/treatment for 6 weeks, total 30 Gy) and for non-responders Botox (10-20 units) or superficial or total parotidectomy
- Anticholinergic pharmacotherapy (propantheline, scopolamine, glycopyrrolate) may be used to reduce saliva production
64
Treatment for hypertrophic scars, keloids
Intralesional steroids can be started 1 monht post-op (triamcinolone 40mg/ml, 0.2ml given every 3 weeks for 3 months). Aggressive injections can lead to significant atrophy.
Silicone sheeting, flashlamp-pumped pulsed dye laser 585 nm or 1064 nd:YAG non-ablative laser, dermabrasion at speed of 35,000 RPM with diamond fraise burrs of medium course can also be used.
Radiotherapy 15-20 Gy over 6 sessions can be considered for refractory cases.
65
Antibiotic to cover ear injuries
Fluoroquinolones are prudent for injuries that involve the cartilage to cover Pseudomonas aeruginosa.
Note that it is toxic to developing cartilage and should not be given to patients under 18 years.
If perichondritis develops, assume it is from this pathogen.
66
Treatment for partial ear avulsion
Mladick techinque (retroauricular pocket): de-epithelialize the amputated auricle, perform anatomic cartilage reattachment, and bury into retroauricular pocket. 2 weeks later, elevate the cratilage and split thickness skin graft.
67
Anterior nasal bleed source
Posterior nasal bleed source
Anterior: (more common) from Kiesselbach area aka Little's area. Anterior and posterior ethmoidal arteries and septal branch of superior labial artery
Posterior: sphenopalatine artery and posterior pharyngeal artery (Woodruff's plexus)
68
Defects up to ___% of the width of the upper lip or ___% of the lower lip can be closed primarily
25% of upper lip
30% of lower lip
can be closed primarily
69
Intermediate defects up to 2/3 of upper or lower lip are reconstructed with which flaps?
Larger defects may require which flaps?
Intermediate: Abbe or Estlander flap
Larger: Karapandzic flap, Gilles flap, or Webster-Bernard Flap
70
How long to splint for DA fracture?
8 weeks
71
3 types of post-traumatic external root resorption
1. Surface resorption (repair-related)
2. Inflammatory resorption (infection-related)
3. Replacement resorption (ankylosis-related)
72
Adult has ambiguous tetanus immunization history or has received fewer than 3 prior doses of tetanus toxoid:
Tetanus immune globulin (TIG) and tetaunus-diphtheria (Td) or tetanus-diphtheria-acellular pertussis (Tdap) vaccine
73
Treatment of subluxation
Flexible splint up to 2 weeks for patient comfort only
74
Treatment of extrusive luxation
Flexible splint 2 weeks
75
Treatment of lateral luxation
Flexible splint 4 weeks
76
Treatment of intrusive luxation
- If incomplete root formation, eruption without intervention. If no movement within a few weeks, orthodontic therapy. If intruded >7mm, reposition surgically or with orthodontics.
- If complete root formation and <3mm intrusion, eruption without intervention. If no movement within 2-4 weeks, reposition surgically or with orthodontics (before ankylosis develops). Stabilize with orthodontics or flexible splint 4-8 weeks.
77
Treatment of alveolar segment fracture
Rigid stabilization 8-12 weeks
78
Treatment of avulsed teeth
Flexible splint 7-10 days
79
Treatment of root fracture
Flexible splint x 4 weeks (if fracture is near cervix, stabilize x 4 months)
80
Periodontal injury: concussion
What is it?
Treatment?
No visible trauma to tooth or alveolar structures, but pain on percussion.
Treatment is conservative, no chew diet and surveillance of pulpal vitality.
81
What is subluxation? Treatment?
Increased mobility of tooth without dislocation. Treatment is conservative, although a flexible splint may be applied for patient comfort for up to 2 weeks.
82
What is extrusion? Treatment?
Coronal dislocation of the tooth due to separation of the PDL without alveolar bone disruption.
Reposition, stabilize 2 weeks with non-rigid flexible splint, and RCT in teeth with closed apices.
83
What is lateral luxation?
Treatment?
Tooth displacement with fracture of the alveolar process.
Flexible splinting 4 weeks, RCT indicated for cases of pulpal necrosis to prevent root resorption
84
What is intrusion? Treatment?
Apical dislocation of the tooth with crushing injury of supporting alveolar bone.
Treatment depends on status of root apex.
Incomplete root formation treated conservatively, allowing passive eruption. Orthodontic repositioning may be attempted after several weeks of conservative treatment.
Complete apical development undergo immediate orthodontic repositioning if intruded more than 3mm (conservative observation if less than 3mm) with orthodontic forces after 2-4 weeks. If 7mm or greater intrusive displacement, immediate surgical repositioning regardless of root apex.
Stabilize 4-8 weeks with flexible splint
RCT 2-3 weeks after injury if complete root formation.
85
Contraindications to tooth replantation in setting of traumatic avulsion
Immunosuppressed patient after transplant surgery
Patients with cardiac valve replacement
86
Avulsed tooth, closed apex, with no dry time, stored in Hanks Balanced Salt Solution <24 hours, milk or saliva <6 hours
Place tooth in doxycycline 0.05mg/ml for 5 minutes then replanted.
Stabilize with flexible wire and composite for 7-10 days
Initiate RCT at 7-10 days (pulp extirpation and calcium hydroxide - effective antimicrobial agent that decreases resorption and promotes healing).
87
Avulsed tooth, open apex, with no dry time (stored in appropriate medium)
Doxycycline 0.05mg/ml 5 mins
Replant
Stabilize flexible wire
Monitor for signs of pulpal necrosis
Apexification therapy performed with calcium hydroxide if pulpal necrosis develops.
88
Avulsed tooth out of mouth for >1h and not stored in appropriate medium
Will have necrotic PDL, poorer prognosis.
PDL debrided by placing tooth in sodium hypochlorite solution for 30 minutes. Extraoral RCT completed with gutta percha. Tooth placed sequentially in citric acid solution for 3 minutes, 1% stannous fluoride solution for 5 minutes, and 0.005% doxycycline solution for 5 minutes. The tooth is then replanted and splinted for 7-10 days.
89
Normal intercanthal distance
30-33mm
90
What can be used to pack off anterior nasal bleeding? Posterior bleeding? How long are they left in place? What other adjuncts can be used for bleeding?
Anterior: Ribbon gauze or Merocel sponges
Posterior: usually requires an anteroposterior pack, which frequently includes a balloon as a means of tamponade.
Packs left in place for maximum of 24-48 hours. Antibiotics are initiated.
Persistent epistaxis = FloSeal or other local hemostatic agents.
91
Immediate vs. delayed nasal bone reduction
Immediate if no significant edema that would compromise assessment of surgical intervention.
With significant edema, surgery should be postponed to allow the edema to resolve (3-5 days). In the case of delayed repair, it is recommended that fractures be treated within 10 days of injury for optimal results (earlier in pediatric population).
92
What if the nasal pyramid does not snap into position and is unstable or "drifts" during closed reduction?
Further intervention is indicated.
- Septoplasty should be considered (esp. in patients with a prior history of nasal obstruction)
- Nasal osteotomies are performed if there is continued drift
- Upper lateral cartilages can be released from the nasal septum
- This can be followed by fracturing of the bony septum (anterior extension of the perpendicular plate of the ethmoid and vomer) opposite the deviation by pushing the bony pyramid toward the contralateral lateral canthus.
- Any residual deformity can be corrected with a cartilage camouflage graft in the depressed area.
- External nasal splint 1-2 weeks and endonasal packing 2-3 days to further stabilize.
93
Most common cause of post-reduction nasal deformity
Undiagnosed or untreated nasal-septal fracture or deviation.
14-50%
94
Kiesselbach's plexus (Little's area)
Vascular area in anterior septum where terminal branches of the internal and external carotid arteries meet.
Anterior ethmoidal, septal branches of the superior labial, sphenopalatine, and greater palatine arteries
Injury to this area can cause septal hematoma in subperichondrial plane, disrupting vascular supply to the septum. Requires immediate evacuation with dependent drainage and intranasal packing.
95
Indications for primary open reduction of nasal fractures
1. Inability of the septum to remain in the reduced position
2. Considerable displacement of cartilaginous structures
3. Bilateral fractures with dislocation of the nasal dorsum and septal pathology
4. Fractures of the cartilaginous pyramid, with or without dislocation of the upper lateral cartilages
5. Anticipation of cartilage or bone grafting
96
Is CT a reliable predictor of nasofrontal duct injury?
No.
97
Management of displaced anterior sinus wall fractures without NFOT involvement
Prevent cosmetic deformity
Access through coronal or local approach (existing lacerations, open sky incision)
ORIF with titanium or resorbable microplates.
Bone grafting considered for avulsed fragments or extensive comminution.
Isolated, non-displaced anterior table fractures should be managed conservatively
98
Management of NFOT injury without significantly displaced posterior table fracture
Presents with significantly displaced frontal sinus fractures or concomitant NOE and LeFort fractures.
If untreated, obstructed NFOT prevents evacuation of mucin and may lead to mucocele or mucopyocele formation, osteomyelitis, sinusitis, meningitis, or brain abscess.
Treatment = complete debridement of sinus mucosa using curette or highspeed burr, obliteration of frontal sinus and nasofrontal duct with various materials (bone, temporalis muscle, fat, fascia, Gelfoam, hydroxyapatite cement. Anterior table replaced and stabilized.
99
Management of posterior table fractures
Can present with intracranial injury, dural tear, and CSF leakage. Manage intracranial injury (often with craniotomy), dural repair, and cranialization (remove posterior table, allowing brain parenchyma to occupy the frontal sinus). NFOT obliteration prior to cranialization with a variety of materials. Pedicled pericranial flap placed after cranialization facilitates separation of the brain from the nasal environment.
100
How do you evaluate patency of the NFOT?
For fractures treated non-surgically, interval CT imaging.
Intraoperatively, inject dye into duct and observe its emergency into nasal cavity (accuracy questionable).
101
How are dural tears repaired?
Primary closure
Fascial graft, fibrin glue
102
Early and late complications frontal sinus fracture
Early: first 6 weeks: CSF leakage, wound infection, meningitis, brain abscess, iatrogenic brain injury, NFOT obstruction, supraorbital nerve paresthesia, diplopia, headache, chronic forehead pain.
Late: 6 weeks - 10 years: cosmetic defects, mucocele or mucopyocele, pneumocephalus, osteomyelitis, intracerebral abscess
103
Meningitis after frontal sinus fracture
Incidence as high as 6%
Altered mental status, fever, neck rigidity
Head CT and lumbar puncture
Empiric broad-spectrum antibiotics with high CSF penetrance (nafcillin)
104
Soft tissue intercanthal distances greater than ___mm are suggestive of displaced NOE fracture, and distances greater than ___mm are diagnostic.
35mm; 40mm
105
What is done when the medial canthal tendon is avulsed?
Canthopexy by transnasal wiring or securing a permanent suture to a transnasal wire that is directed superiorly and posteriorly.
106
Repair of nasolacrimal apparatus (early vs. delayed)
Use of a stent (Crawford tube) which acts to bridge the two severed ends of the canaliculi, and careful closure of pericanalicular tissues.
Refractory or uncorrected epiphora necessitates correction through a dacrocystorhinostomy (small incision midway between corner of eye and bridge of nose, lacrimal sac is located, incised, then connected to the nasal mucosa, creating a new tear drainage pathway. Stent placed for a few months).
107
Where does the nasolacrimal duct drain?
Beneath the inferior turbinate 11-17mm above the nasal floor and 11-14mm posterior to the piriform aperture
108
What can be used for posterior nasal packing?
Foley catheter, nasal balloon, endotracheal tube
Pass into nares and beyond the nasopharynx, balloon inflated, and catheter is advanced until the balloons occlude the posterior nasal aperture.
109
Irregular pupil shape
Tear-shaped pupil points to the site of rupture
110
What is a reliable indicator of adequacy of resuscitation and mortality in trauma patients (better marker of blood loss than hemoglobin and hematocrit)?
Base deficit
111
Fixation in LeFort II fractures
Fixation in LeFort III fractures
LeFort II: nasofrontal region, inferior orbital rim, ZM buttress
LeFort III: nasofrontal region, lateral orbital rim (ZF), and zygomatic arch (ZT)
112
Normal intraocular pressure
11-20mmHg
(low = globe rupture)
(high = retrobulbar hemorrhage)
113
Most sensitive/best measure of optic nerve function
Red object held in front of the patient. Assess if same color/hue and brightness/intensity in each eye.
If optic nerve has been damaged (optic neuritis or increased IOP), red object is duller and more brown/grayish in affected eye compared to contralateral eye.
114
Describe how you perform a forced duction test
Topical anesthetic
Two fine forceps used to carefully move the eye in directions of gaze while feeling for mechanical restriction.
115
Absolute indications for orbital floor repair
(what are some relative indications)
- Globe malposition with acute enopthalmos and/or hypoglobus
- Immediate correction of diplopia in setting of muscle (inferior rectus) incarceration and a positive forced duction test result, or unresolved diplopia with a positive forced duction result
- Immediate correction in the symptomatic pediatric patient with an orbital floor "trapdoor" fracture that has elicited the oculocardiac reflex (the oculocardiac reflex can be seen with true entrapment)
(Relative indications = prevention of a cosmetic deformity. Disruption of >50% of the orbital floor is likely to cause cosmetically apparent enophthalmos, especially with fractures in the critical area at the junction of the floor and medial wall. Correction of unresolved diplopia at 7-11 days in the setting of soft tissue prolapse).
116
Contraindications to immediate orbital floor repair
- Any condition that puts the globe in jeopardy (ocular injuries like hyphema, retinal tears, lens displacement).
- The status of the non-injured eye as a possible contraindication. Diplopia (binocular) would not be possible in a patient with one blind eye. Only indication would be to prevent globe malposition).
