Trauma Flashcards
<p>Damage to which portion of frontal sinus would most likely involve the naso-frontal ducts? A. Posterior wall B. Medial portion of floor C. Anterior wall D. Lateral portion of floor</p>
<p>Answer: B Rationale: Damage to the medial portion of the frontal sinus most often involves damage to the naso- frontal ducts. This is an important area to evaluate intraoperatively to evaluate the patency of the naso-frontal ducts. Other areas mentioned do not involve the NFD's. Posterior wall fractures involve the brain, and the lateral aspect of the sinus can involve the orbital roof. Reference: Fonseca. Oral and Maxillofacial Trauma. Evaluation and management of frontal sinus injuries, p 721-736, 2005. Peterson. Principles of Oral and Maxillofacial Surgery. Management of frontal sinus and naso-orbitalethmoid complex fractures, 491-508, 2004.</p>
<p>During a Gillies approach to access the zygomatic arch, the plane of dissection is between which two anatomic layers?
A. Superficial and deep layers of deep temporalis fascia
B. Temporoparietal fascia and superficial layer of deep temporalis fascia
C. Subcutaneous fat layer and temporoparietal fascia
D. Deep layer of deep temporalis fascia and temporalis muscle</p>
<p>Answer: D
Rationale:
The Gillies approach to reduce a zygomatic arch fracture utilizes a dissection between the deep layer of the deep temporalis fascia and the temporalis muscle. The plane of dissection is sub-fascial, but supra-muscular. Dissection in the temporoparietal fascia may damage the facial nerve and will not reach the zygomatic arch. Since the two layers of the deep temporal fascia split to envelop the arch, dissection must be maintained between the muscle and deep layer of the deep temporal fascia in order to place the elevator deep to the arch.
American Board of Oral and Maxillofacial Surgery
144
2008 Oral and Maxillofacial Surgery Self Assessment Tool (OMSSAT)
Reference:
Fonseca. Oral and Maxillofacial. Trauma. Evaluation and management of frontal sinus injuries, p 721-736, 2005.
Peterson. Principles of Oral and Maxillofacial Surgery. Management of frontal sinus and naso-orbitalethmoid complex fractures, 491-508, 2004.</p>
<p>The marginal mandibular nerve is:
A. anterior to the facial artery, but not the vein, in 100% of cases.
B. anterior to the facial vein, but not the artery, in 100% of cases.
C. below the inferior border of the mandible in 19% of the cases where the nerve is posterior to the facial vessels.
D. below the inferior border of the mandible in 5% of the cases where the nerve is anterior to the facial vessels.</p>
<p>Answer: C
Rationale:
The classic 1961 study by Dingman and Grabb showed the relationship of the marginal mandibular branch of the facial nerve in relation to the facial vessels. In 81% of the cases, the nerve was superior to the inferior border of the mandible posterior to the vessels. In 19% of the cases, the nerve ran up to 1 centimeter inferior to the inferior border of the mandible posterior to the vessels, and in 100% of cases, when the nerve was anterior to the vessels, the marginal mandibular branch ran above the inferior border of the mandible. Since the marginal mandibular branch runs from posterior to anterior, it cross the vertically running facial artery and vein and therefore always is found to run anterior to both facial vessels.
Reference:
Dingman RO, Grabb WC. Surgical anatomy of the mandibular ramus of the facial nerve based on the dissection of 100 facial halves. Plastic Reconstrutive Surgery Vol 29, 1962.
Ziarah HA, Atkinson ME. The surgical anatomy of the mandibular distribution of the facial nerve. Br J Oral Surg. 1981 Sep; 19(3):159-70.</p>
<p>The Keen technique is utilized to reduce fracture of what structure? A. Mandibular condyle B. Medial canthal tendon C. Coronoid process D. Zygomatic arch</p>
<p>Answer: D
Rationale:
Keen and Carmedy-Baxon approaches are the two classic methods of approaching and reducing a zygomatic arch trans-orally. Buccal sulcus (vestibular) is the Keen approach, while the lateral coronoid approach (along the ascending ramus) is known as the Carmedy- Baxon. These two approaches allow reduction of a fractured arch The Keen approach allows access to the infraorbital rim and nasomaxillary region as well while the Carmedy- Baxon approach is somewhat more limited in exposure.
Reference:
Quinn JH. Lateral coronoid approach for intraoral reduction of fractures of the zygomatic arch. J Oral Surg 35; 1977.
Courtney DJ. Upper buccal sulcus approach to management of fractures of the zygomatic complex: a retrospective study of 50 cases. Br J Oral Maxillofac Surg, 37, 1999.</p>
<p>What is the most important bony suture for future growth when treating a naso-septal fracture in the pediatric population? A. Nasomaxillary B. Nasofrontal C. Septovomerine D. Frontoethmoidal </p>
<p>Answer: C
Rationale:
The septovomerine junction is considered a growth center in the pediatric nose. Therefore, adequate reduction of this region is imperative to decrease risk of premature ossification which can lead to future growth disturbance.
Reference:
Haug RH.. Maxillofacial injuries in the pediatric patient. Oral Surg, Oral Medicine, Oral Path, 90, 126, 2000.
Rock WP, Brain DJ. The effects of nasal trauma during childhood upon growth of the nose and midface. Br J Orthod 10: 38, 1983.</p>
<p>What is the most important factor in re-establishment of the vertical facial height in the management of pan-facial fractures?
A. Reduction of mandibular condyle fractures
B. Reduction of fronto-zygomatic sutures
C. Establishing proper zygomatic projection
D. Establishing proper dental occlusion</p>
<p>Answer: A
Rationale:
There are several key landmarks when treating pan-facial injuries. While re-establishing proper occlusion is a key component, the posterior facial height and ramus/condyle units must be aligned properly in order to gain vertical height of the face. This is accomplished by proper reduction of mandibular condyles after proper occlusion is established. If teeth are not present, then anatomic reduction of the mandible and/or maxilla must be performed in order to establish proper vertical height. Once proper occlusion and vertical ramus height are established, alignment of vertical and horizontal facial bony buttresses is accomplished.
Reference:
Peterson. Principles of Oral and Maxillofacial Surgery. Management of panfacial fractures, 547-562, 2004.
Markowitz BL, Manson PN. Panfacial fractures: organization of treatment. Clin Plast Surg 16; 105, 1989.</p>
<p>Between which two anatomic layers is the safest plane of dissection during the initial elevation of a coronal flap?
A. Subcutaneous fat and galea
B. Pericranium and galea
C. Subcutaneous fat and temporoparietal fascia D. Galeal fat pad and temporal fat pad</p>
<p>Answer: B
Rationale:
The safest plane of dissection in a coronal flap elevation is the subgaleal plane located between the galea and the pericranium. At this level, the frontal branch is above (superior) the level of the dissection and thus is less susceptible to injury.
Reference:
Frodel JL, Marentette LJ. The coronal approach. Anatomic and technical considerations and morbidity. Arch Otolaryngol Head Neck Surg. 1993 Feb; 119(2):140.
Liebman EP, Webster RC, Berger AS, et al. The frontalis nerve in the temporal brow lift. Arch Otolaryngol 1982 Apr; 108(4):232-5.
</p>
<p>What is the most frequently fractured area of the edentulous mandible? A. Condyle B. Subcondyle C. Symphysis D. Body </p>
<p>Answer: D
Rationale:
43.5% of all fractures of the edentulous mandible occur in the body region. This is compared to only 33% in the dentate patient. The body fracture is the most frequently fractured segment of the edentulous mandible.
Reference:
Bruce RA, Strachan DS. Fractures of the edentulous mandible: the Chalmers j. Lyons Academy stud. J Oral Surg, 34:9073, 1976.
Peterson 2nd edition, Principles of Oral and Maxillofacial Surgery, Principles of management of mandibular fractures, 401-434, 2004
Fonseca, Oral and Maxillofacial Trauma, Mandibular fractures, P 479-522, 2005</p>
<p>What is the mostly commonly used endoscope (offset degree of angulation and diameter) for repair of mandibular condyle fractures? A. 30 degrees, 2mm B. 0 degrees, 2 mm C. 30 degrees, 4mm D. 0 degrees, 4 mm</p>
<p>Answer: C
Rationale:
Although endoscopically assisted condyle repairs are not as commonly performed as the more traditional methods, the most commonly used endoscope is a 30', 4 mm endoscope. This technique requires making a Rison incision and inserting an endoscope while reducing the fracture. Application of fixation can be done directly or via a trocar system.
Reference:
Martin M, Lee C. Endoscopic mandibular condyle fracture repair. Atlas Oral Maxillofac Surg Clin N Am, 11, 2003.
Troulis MJ. Endoscopic open reduction and internal rigid fixation of subcondylar fractures. J Oral Maxillofac Surg 62, 2004.</p>
<p>Which of the following differentiates between superior orbital fissure syndrome and orbital apex syndrome? A. Ophthalmoplegia B. Loss of vision C. Ptosis of the upper lid D. Anesthesia of the forehead </p>
<p>Answer: B
Rationale:
Loss of vision is the defining clinical sign which differentiates superior orbital fissure syndrome from orbital apex syndrome. All other signs and symptoms listed are seen in both conditions. Ophthalmoplegia occurs due to involvement of cranial nerves III, IV, VI. Anesthesia occurs due to the involvement of V1. Ptosis occurs due to loss of sympathetic tone to the Muller's muscle; since the terminal sympathetic fibers travel with the ophthalmic branch of the trigeminal nerve (V1.)
Reference:
Peter ward Booth (ed); Maxillofacial trauma; Periorbital and intraorbital trauma and orbital reconstruction, P 205-222, Churchhill Livingstone; 2003
Eo S, Kim JY, Azari K. Temporary orbital apex syndrome after repair of orbital wall fracture. Plast Reconstr Surg. 2005 Oct; 116(5):85e-89e</p>
<p>Which of the following can cause binocular diplopia? A. Retinal detachment B. Lens dislocation C. Corneal scarring D. Alteration in globe position </p>
<p>Answer: D
Rationale:
Binocular diplopia is more common than monocular diplopia; however both can result from traumatic insult to the globe. Retinal detachment, lens dislocation, cataracts, and corneal scarring are causes of monocular diplopia. Globe position changes can lead to binocular diplopia.
Reference:
Peter ward Booth (ed); Maxillofacial trauma Periorbital and intraorbital trauma and orbital reconstruction, P 205-222, Churchhill Livingstone; 2003
Michael Miloro (ed); Peterson's principles of Oral and Maxillofacial Surgery 2nd edition, Orbital and ocular trauma, P 463-490, BC Decker Inc, 2004</p>
<p>What is the mean distance of the optic canal from the posterior ethmoidal foramen? A. 1mm B. 5mm C. 10 mm D. 12mm</p>
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<p>Answer: B Rationale: When measuring from the anterior lacrimal crest the mean distance of the anterior and posterior ethmiodal foramen are 24 and 36mm respectively, the optic canal is a mean of 5mm posterior to the posterior ethmiodal foramen (or a mean of 42mm from the anterior lacrimal crest). Reference: Michael Miloro (ed); Peterson's principles of Oral and Maxillofacial Surgery 2nd edition, BC Decker Inc, Orbital and ocular trauma, P 463-490,2004, Ray Fonseca (ed); Oral and Maxillofacial Surgery, volume 3; Orbital Trauma, p 205-244, WB Saunders, 2000 <img></img></p>
What is the greatest width of an upper eye lid defect that can be repaired by primary closure without compromising function? A. 10% B. 15% C. 20% D. 25%
Answer: D
Rationale:
Eyelid injuries involving less then 25% can be closed primarily, those which are 25-50% can be repaired with local tissue advancement. Those greater then a 50% defect will require a flap or skin graft which replaces both the anterior and posterior lamellae.
Reference:
Michael Miloro (ed); Peterson’s principles of Oral and Maxillofacial Surgery 2nd edition, BC Decker Inc, Orbital and ocular trauma, P 463-490, 2004
Ray Fonseca (ed); Oral and Maxillofacial Surgery, volume 3; Orbital Trauma, p 205- 244WB Saunders, 2000
A 30 year-old male has bilateral lower leg deformities following a motor vehicle collision. He is anxious, with the follwing vital signs: BP = 130/100, pulse = 110, respiratory rate = 28What is his class of blood loss? A. Class I B. Class II C. Class III D. Class IV
Answer: B
Rationale:
Class II Hemorrhage represents volume loss of 750 to 1500ml of blood. Clinical symptoms include tachycardia, tachypnea and a decrease in pulse pressure. This decrease in pulse pressure is primarily related to a rise in the diastolic component due to an increase in circulating catecholamines which increase the vascular tone and resistance. Systolic pressure changes minimally in early hemorrhagic shock.
Reference:
Advanced Trauma Life Support Student Manual. Shock, 87-107, American College of Surgeons. Sixth Edition. 1997.
Miloro, M. et al, Peterson’s Principles of Oral and Maxillofacial Surgery, Second Edition, Initial management of the trauma patient, p 327-356, BC Decker 2004.
A 25 year-old male presents unconscious following a fall. Neurological evaluation shows that he withdraws from pain, there is no verbal response, and there is no eye opening. What is his Glasgow Coma Score? A. 4 B. 5 C. 6 D. 7
Answer: C
Rationale:
Glasgow Coma Scale is based on three variables: best motor response, best verbal response and eye opening. (GCS = M+V+E) Scores range from 3 to 15. In this case withdrawing from pain represents 4, no verbal response represents 1 and no eye opening represents 1. GCS = (M4+V1+E1) = 6
Reference:
Advanced Trauma Life Support Student Manual. Shock, 87-107, American College of Surgeons. Sixth Edition. 1997.
American Board of Oral and Maxillofacial Surgery
158
2008 Oral and Maxillofacial Surgery Self Assessment Tool (OMSSAT)
Miloro, M. et al, Peterson’s Principles of Oral and Maxillofacial Surgery, Second Edition,
Initial management of the trauma patient, p 327-356, BC Decker 2004. .
After a severe head trauma, the intracranial pressure of 45 year-old male is 30mm Hg. Other vital signs include pulse 90, respiratory rate 20, and blood pressure 130/85. What is the cerebral perfusion pressure of this patient? A. 50 B. 60 C. 70 D. 80
Answer: C
Rationale:
Cerebral blood flow, maintained by autoregulation, depends on cerebral perfusion pressure and intracranial pressure. Cerebral perfusion pressure is the mean arterial blood pressure minus intracranial pressure. (CPP = MAP ñ ICP). Normal CPP in an adult is >50 mm Hg.
One method for the calculation of the mean arterial pressure is diastolic pressure times 2 plus systolic pressure all divided by three.
{MAP = [(2 x Diastolic Pressure) + Systolic Pressure] / 3}
=[(2 x 85) + 130] / 3
=100
CPP = 100 ñ 30 CPP = 70
Reference:
Advanced Trauma Life Support Student Manual. Shock, 87-107American College of Surgeons. Sixth Edition. 1997.
Way, L et al. Current Surgical Diagnosis and Treatment. Fluid and electrolyte management, 129-142, Eleventh Edition. McGraw Hill. 2003.
A 2 year-old male presents with second degree burns of his entire head. What percentage of his body surface area is involved? A. 4.5% B. 9% C. 10% D. 18%
Answer: D
Rationale:
The ìRule of Ninesî is a useful and practical guide to determine the extent of the burn and fluid resuscitation. The infant’s head represents a larger proportion of the surface area. The percentage of total body surface of the infant’s head is twice that of the normal adult (which is 9%).
Reference:
Advanced Trauma Life Support Student Manual. Pediatric trauma, p 289-311, American College of Surgeons. Sixth Edition. 1997.
Way, L et al. Current Surgical Diagnosis and Treatment. Fluid and electrolyte management, 129-14 Eleventh Edition. McGraw Hill. 2003.

Which of the following is a component of Beckís triad? A. Wide pulse pressure B. Decreased central venous pressure C. Increased systolic arterial pressure D. Muffled heart tones
Answer: D
Rationale:
Beck’s triad for diagnosis of cardiac tamponade consists of venous pressure elevation, decline in arterial pressure and muffled heart tones. Wide pulse pressure is seen in shock.
Reference:
Advanced Trauma Life Support Student Manual. Thoracic trauma, p 125-141, American College of Surgeons. Sixth Edition. 1997.
Miloro, M. et al, Peterson’s Principles of Oral and Maxillofacial Surgery, Second Edition, Initial management of the trauma patient, p 327-356BC Decker 2004.
What is the most common midfacial fracture in the pediatric population? A. Orbital roof B. Orbital floor C. Zygomatico-maxillary D. Nose
Answer: D
Rationale:
The nose is a prominent structure in children and the nasal bones are fragile. Nasal fractures are the most common midfacial skeleton injury in children. The low incidence of midfacial fractures in children can also be explained by the elasticity of the child’s facial bones, the retrusive position of the maxilla, nose and infraorbital rims and the anatomic protection afforded by the cranium.
Reference:
Kaban LB, et. al. Pediatric Oral and Maxillofacial Surgery. Ch. 24 Facial Trauma I: Midfacial Fractures, Baumann A, et. al. p.426.
2 Posnick JC. Craniofacial and Maxillofacial Surgery in Children and Young Adults. Ch 30 Primary Craniomaxillofacial Fracture Management, Posnick JC. p.720.
The clinical sign differentiating superior orbital fissure syndrome from orbital apex syndrome is: A. absence of superior palpebral fold B. proptosis C. dilated and fixed pupil D. decreased visual acuity
ANSWER: D
RATIONALE:
Symptoms of superior orbital fissure syndrome include:
1. Pupillary dilation via alteration in cranial nerve III function in it’s innervation of the
pupillary constrictors.
2. Paresis of cranial nerves III, IV, and IV causing ophthalmoplegia.
3. Cranial nerve III involvement causes paresis of the levator palpebrae superiorus muscle,
leading to ptosis and loss of the superior palpebral fold.
4. Neurosensory disturbance to the first division of cranial nerve V with hypesthesia of the
supraorbital and supratrochlear nerves and loss of the corneal reflex.
5. Proptosis from engorgement of the ophthalmic vein and lymphatics.
The orbital apex syndrome includes all of the above plus optic nerve involvement, leading to changes in visual acuity.
Post auricular ecchymosis in cases of high velocity trauma is usually indicative of: A. fracture of the vertex of the skull B. mandibular fracture C. basilar skull fracture D. LeFort III fracture
ANSWER: C
RATIONALE:
A fracture of the skull base results in the extrusion of blood subperiosteally. This hematoma or ecchymosis may be exhibited at the thin skinned mastoid region (post- auricular), as hemotympanum, as bilateral periorbital ecchymosis, or as a posterior pharyngeal ecchymosis or hematoma.
Alignment of which of the following is the most reliable for proper reduction of the zygomaticomaxillary complex fracture? A. Frontozygomatic suture B. Sphenozygomatic suture C. Infraorbital rim D. Medial orbital rim
ANSWER: B
RATIONALE:
The sphenozygomatic suture area has been previously analyzed and shown to be an area for confirmation of alignment of the zygomatic arch and the zygomatic complex (ZMC). This has also been shown to key point for fixation thru biomechanical studies.
The sphenozygomatic suture is a broad area along the greater wing of the sphenoid and can be approached along the internal aspect of the lateral orbit. Even in severe midface fractures the greater wing of the sphenoid is intact thus acting as a key landmark for proper reduction of the ZMC fracture.
Reduction of the frontozygomatic suture or the infraorbital rim alone can result in errors due to the small surface area. The medial orbit is generally not involved in a ZMC fracture.
Which of the following is the least cosmetic surgical approach for an adolescent with an orbital floor fracture?
A. Subciliary incision
B. Post septal transconjunctival incision
C. Infraorbital incision
D. Preseptal transconjunctival incision.
ANSWER: C
RATIONALE:
Although the infraorbital incision provides direct and excellent exposure of the orbital rim and floor with a low incidence of complications, it frequently produces a noticeable scar. In younger people, this scar increases in size with growth. The subciliary incision is more cosmetic. Whether pre- or post-septal, the transconjunctival incisions do not involve the skin and are cosmetically hidden.
The first step in the general order of treatment of panfacial fractures is:
A. Establish soft and hard tissue reduction
B. Expose all fracture sites
C. Alleviate soft tissue entrapments
D. Apply internal fixation
ANSWER: B
RATIONALE:
The first issue in the order of treatment of panfacial fractures is to ascertain the sites and conditions of the disrupted anatomical structures. This can only be accomplished by exposure of the entire injured facial skeleton. Soft tissue entrapments are next alleviated, the osseous fractures are then reduced, and rigid fixation is applied followed by soft tissue approximation.
Acute dacryocystitis following trauma is treated by all of the following except:
A. warm compresses
B. intubation of the canaliculi and injection of dye
C. systemic or topical nasal decongestants
D. incision and drainage
ANSWER: B
RATIONALE:
Dilation, intubation and dye injection are diagnostic, not therapeutic measures. Moreover, these maneuvers should not be attempted in the face of an acute dacryocystitis. Incision and drainage of the lacrimal sac, administration of medicaments (systemic or topical decongestants,) or palliative care(warm compresses) are acceptable treatment modalities.
Epiphora can be caused by all of the following except:
A. Telecanthus with rounding of the medial canthus
B. Entropion of the lower lid
C. Ectropion of the lower lid
D. A soft tissue laceration of the lateral aspect of the upper eyelid
ANSWER: D
RATIONALE:
Ectropion and entropion can affect the contact of the inferior lacrimal punctum with the tear fluid decreasing lacrimal fluid flow through the punctum and leadin to epiphora. Traumatic telecanthus can also lead to alterations in tear flow and drainage in the medial aspect of the inferior palpebral area and decrease lacrimal drainage through the inferior canilculus. The codnition affect lacrimal fluid drainage but not lacrimal fluid delivery to the palpebral fissure. Although a laceration through the laterial aspect of the upper eyelid can disrupt tear flow from the lacrimal gland, such a decrease in tear production would not lead to epiphora.
Disruption of the nasolacrimal apparatus with subsequent epiphora occurs most commonly after which facial fracture: A. Nasal B. LeFort III C. Nasoethmoidal D. Zygomaticomaxillary
ANSWER: C
RATIONALE:
The incidence of nasolacrimal disruption is 0.2% following nasal fracture, 3-4% following midface fractures, 17-21 % following naso-ethmoidal fractures, almost non existent following zygomatic-maxillary fractures. The location of the zygoma is so far removed from the lacrimal apparatus so as to make it a concomitant injury.
Confirmation of a CSF leak following a fontal sinus fracture is best done with which of the following imaging studies?
A. A high resolution computed tomography cisternogram after administration of intrathecal fluorescein
B. A facial series of radiographs to include a Caldwell and lateral view
C. A non contrast computed tomography study of the brain
D. Magnetic resonance imaging of the base of the skull
ANSWER: A
RATIONALE:
Plane radiography is incapable of confirming a CSF leak. While magnetic resonance is helpful with soft tissues, without dye, this diagnostic aid is useless. A similar rationale exists for non- contrast CT. An intrathecal injection of dye, and confirmation of the dye at distant sites is diagnostic.
The most likely diagnosis in a patient with painful proptosis, progressive visual loss, restricted extraocular movement, and increased intraocular pressure following surgery to reduce a zygomatic fracture is: A. Horner’s syndrome B. Movement of an alloplastic implant C. Injury to the infraorbital nerve D. Retrobulbar hematoma
ANSWER: D
RATIONALE:
Movement of an alloplastic implant is generally asymptomatic. Injury to the infraorbital nerve produces anesthesia or paresthesia over it’s cutaneous distribution (the lower eyelid area). Horner’s syndrome, caused by a disruption in the sympathetic innervation to the upsilateral maxillofacial region, is characterized by: a constricted pupil (by unopposed parasympathetic constriction), ptosis (by loss of smpathetic inneration to Mueller’s muscle), and anhidrosis (by interruption of sympathetic innervation to cutaneous sweat glands). The symptoms described are most consistent with retrobulbar hematoma, and require prompt diagnosis and intervention.
Suspension wires utilized to stabilize a LeFort I fracture resists forces in which direction? A. Superior B. Inferior C. Anterior D. Posterior
ANSWER: B
RATIONALE:
The recent development and improvements in miniaturized bone plate systems has greatly enhanced treatment of midface fractures and diminished but not obviated the need for wire suspension with direct wiring techniques. While wires may provide minor resistance to deformation in an anterior and posterior direction, they offer no resistance superiorly. The best answer is that the resist deformation in an inferior direction and thereby resist facial elongation.
When evaluating visual acuity in the orbital trauma patient:
A. The pupils should be dilated.
B. Eyeglasses should not be worn by the patient, even if available.
C. Viewing through a pinhole can compensate for some refractory errors.
D. Topical tetracaine can aid acuity evaluation.
ANSWER: C
RATIONALE:
Dilation may mask signs and symptoms of neurologic injury. Pupillary dilation does not aid in a visual acuity examination but is utilized to fully visualize the retina, vessels and the optic disc. Pre-existing visual acuity defecits (such as myopia and presbyopia) can mimic traumatic visual acuity loss; and therefore the use of prescription eyeglasses can facilitate the distinction of pretaumatic from traumatic visual defecits. Topical tetracaine is a local anesthetic and is of no value in the evaluation of visual acuity. If pretraumatic myopia is prsent, acuity evaluation while looking through a pinhole can substitute somewhat for corrective lenses if such lenses are not available.
Which of the following is true when treating eyelid lacerations:
A. Eyelid and ocular mobility should be evaluated before injecting local anesthetic.
B. Fat herniation is not an indication of orbital septum violation.
C. Fat herniation is not an indication of possible globe penetrating injury.
D. Iridocyclitis describes an irregularly shaped pupil which “points” away from the area of
globe injury.
ANSWER: A
RATIONALE:
Iridocyclitis is a traumatic anisocoria and many times points towards the injury. Fat herniation occurs with aging and of itself is not necessarily indicative of traumatic septum violation. Herniated fat without lid laceration is therefore of no consequence; however, fat herniation through a lid laceration indicates septum violation and mandates the need for careful evaluation for penetrating globe injury. Penetrating globe injury is diagnosed by visualization of the globe surface. The lid should be examined prior to the administration of local anesthesia because edema and local anesthesia may limit motility.
Which of the following is true when treating injuries of the external ear:
A. Cartilage should never be sutured, thereby avoiding necrosis.
B. Loose or macerated skin should be extensively débrided.
C. Cartilage lacerations should be sutured with conventional, interrupted chronic gut sutures
to encourage overlapping.
D. Cartilage should be sutured with slowly resorbable figure-of-eight sutures.
ANSWER: D
RATIONALE:
Cartilagenous lacerations should be approximated to reconstruct anatomy and prevent chronic chondritic inflammation. Interrupted sutures may promote cartilage margin overlap; the use of figure of eight sutures prevents overlap of lacerated cartilage margins. Cartilage has a limited vascurlar supply, originating from overlying soft tissue; therfore extensive debridement of overlying soft tissue should be discourage.
When the medial canthal ligament is attached to a bony segment in naso-orbito-ethmoidal(NOE) fracture repair the transcanthal wire is best placed:
A. after all soft tissue injuries have been addressed.
B. anterior to the original insertion of the canthal ligament.
C. posterior and inferior to the original insertion.
D. posterior and superior to the original insertion.
ANSWER: D
RATIONALE:
The purpose of the trans-canthal wire is to secure the canthal ligament and boney segment in the pretraumatic position. Pull of the soft tissues displaces the bone and canthal ligament in an anterior and inferior direction. Therefore a wire placed posterior and superior to the original insertion provides a vector whose resistance to displacement is most ideal and provides the best alignment.
An 18-year-old man is stabbed to the left upper chest. You record a blood pressure of 75/60. He is gasping for air, breath sounds are diminished on the left, and his trachea is deviated to the right. The initial treatment should be:
A. Perform tracheal intubation.
B. Obtain a chest x-ray to verify the pneumothorax.
C. Place a chest tube between the anterior and midaxillary line in the fifth intercostal space.
D. Perform needle decompression of the left chest.
ANSWER: D
RATIONALE:
This is a classic tension pneumothorax and treatment is a clinical diagnosis with immediate needle decompression of the second intercostal space, midclavicular line The time involved in waiting for a chest x-ray might prove lethal. Insertion of a chest tube in a controlled fashion to facillitate lung re-expansion normally follows needle deompression of the tension pneumothroax. Endotracheal intumbation with positive pressure ventilation often worsen a tension pneumothrorax, but may be indicated for other types of chest injuries.
A 21-year-old female is an unrestrained driver involved in a MVA. She suffers a scalp laceration and is noted to have lost 1000mL of blood at the scene. You would expect her vital signs to be consistent with:
A. Pulse rate >100, normal systolic blood pressure, decreased pulse pressure, respiratory rate of 20-30, urinary output of 20-30mL/hr.
B. Pulse rate 30mL/hr.
C. Pulse rate >120, decreased systolic blood pressure, decreased pulse pressure, respiratory rate of 30-40, urinary output of 5-15mL/hr.
D. Pulse rate >140, decreased systolic blood pressure, decreased pulse pressure, respiratory rate of >35, urinary output that’s negligible.
ANSWER: A
RATIONALE:
These findings are consistent with a Class II hemorrhage, 750-1500ml, The vitals signs or such a blood loss are consistent with those in response A. Response D reflects the vital signs of a Type IV blood loss, Response C a Type III and Response B a Type I.
A 65-year-old man fell down the stairs. Upon examination of him, you notice that he opens his eyes to speech, localizes pain, and mutters inappropriate words. You assess his Glasgow coma scale (GCS) to be: A. 13 B. 11 C. 9 D. 7
ANSWER: B
RATIONALE:
According to the Glascow Coma Scale, the patient can open his eyes in response to commands speech, (3 out of 4); localizes pain, (5 out of 5); yet produces inappropriate words, (3 out of 6); for a Glascow coma score of 11.
The most frequent location of internal orbital injury in children seven years old and under is the? A. floor B. medial wall C. lateral wall D. roof
ANSWER: D
RATIONALE:
Fronto-orbital injuries are the most frequent in this age group. Because the antrum, sphenoid, ethmoid and frontal sinuses are not yet pneumatized in this age group, fronto-basilar (or roof) injuries most commonly occur. Wall or floor injuries occur in young children.
After nasal injuries in children, growth disturbance are most associated with premature ossification of which suture? A. Nasofrontal B. Septovomerine C. Nasomaxillary D. Nasoethmoidal
ANSWER: B
RATIONALE:
The septovomerine suture determines growth in this area. If this suture is involved in trauma growth consequences are a concern since neither of the other sutures, if involved, provides as deforming a growth consequence.
When reconstructing an orbital floor injury, the safe distance for dissection from the infraorbital rim to the anulus of Zinn is up to how many millimeters? A. 20 B. 25 C. 35 D. 40
ANSWER: D
RATIONALE:
According to a recent cadaveric study involving specimens with intact soft tissue, the mean distance from the inferior orbital rims to the annulus of Zinn is 39.4 mm +/- 2/9 mm. Previously cited studies on dry skulls, using bony landmarks only with no soft tissue references at the orbital apex provide clinically less useful information.
The most common chronic problem associated with the surgical treatment of frontal sinus fractures is? A. The development of mucoceles B. Chronic pain C. Osteomyelitis D. Contour deficits and irregularities
ANSWER: B
RATIONALE:
With the advent of rigid internal fixation, contour deficits and irregularities are infrequent. Using modern aseptic protocols, osteomyelitis is very uncommon. While mucoceles do occur in rare instances when sinus membrane regenerates, pain remains the most frequent of chronic problems.
Patients who survive facial fractures are most likely to have suffered what forms of facial injury? A. Upper only B. Mid only C. Lower only D. Combinations of lower, mid and upper
ANSWER: C
RATIONALE:
Mandibular injury is associated with c-spine injury, but mid- and upper are associated with death. Mid- and upper-facial third injuries initially act as shock absorbers until a particular magnitude of impact, after which they transmit force to the neurocranium. The more commonly results in fatality than does trauma to the lower 1/3 of the facial skeleton.
The intercanthal distance in the uninjured adult patient is approximately: A. 25-30 mm B. 31-35 mm C. 36-40 mm D. 41-45 mm
ANSWER: B
RATIONALE:
The inter-canthal distance in adult Caucasians is 33 + mm. This varies minimally with gender and race. The other answers are outside of this range.
Which of the following is true of the annulus of Zinn?
A. It is attached to the lacrimal, ethmoid and sphenoid bones.
B. It contains the ophthalmic artery and its branches.
C. It is the origin of the rectus and oblique muscles.
D. It contains the maxillary and ophthalmic divisions of the trigeminal nerve.
ANSWER: B
RATIONALE:
The annulus of Zinn contains the ophthalmic artery and its branches. The oblique muscles originate outside of the annulus. The annulus is distant from the lacrimal bone, and does not contain the maxillary division of the trigeminal nerve.
Which of the following is the best definition in the Markowitz and Manson classification system of a Type II nasoethmoidal injury?
A. a single large fragment, with the canthal ligament attached. B. minor comminution, with the canthal ligament attached.
C. comminution beneath the canthal ligament.
D. comminution with the canthal ligament detached.
ANSWER: B
RATIONALE:
Below are figures adapted from the original article on nasoethoidmal fractures published by Markowitz and Manson in 1991. Choice B is the correct answer. Choice A represents a Type I fracture. Choice C doesn’t fit into any classification scheme since it doesn’t address the region of the canthal ligaments. Choice D represents a Type III fracture. This figure depicts the nasoethmoidal region. The region shaded is the central fragment. The inset figure represents a Type I fracture, where the canthal ligament is attached to a large central fragment and there is no comminution of the fractured nasoethmoidal region. This figure represents a Type II fracture. There is some comminution of the nasoethmoidal region but the canthal ligament is attached to a substantial fragment of bone. This figure represents a Type III fracture. The canthal ligament is detached or there is severe comminution with the canthal ligament attached to a small fragment of bone.
When repairing cranial bone trauma utilizing a coronal approach, the temporal branches of the facial nerve can best be preserved by:
A. avoid extending the incision into the preauricular areas
B. confining the surgical dissection between the superficial temporal fascia and the deep
temporal fascia
C. insuring the surgical dissection is deep to the superficial layer of the deep temporal fascia
D. avoid reflecting the periosteum of the zygomatic arch.
ANSWER: C
RATIONALE:
The temporal branches lie immediately beneath the superficial layer of the temporal fascia, just above the superficial layer of the deep temoral (temporalis) fascial. Dissection below the superficial temporal fascia this layer may injure the nerve. Dissection beneath the superficial layer of the deep temporal fascia preserves the temporal facial nerve branches.
Which of the following surgical approaches for repair of orbital trauma has the highest incidence of post operative scleral show?
A. Transconjunctival without lateral cantholysis B. Infraorbital (orbital rim)
C. Upper eyelid blepharoplasty
D. Subciliary
ANSWER: D
RATIONALE:
Several studies have shown that the subciliary approach has the highest rate of post operative scleral show. The scar contracture associated with the infraorbital approach does no affect the orbicularis to the same degree as for other incisions. The transconjunctival incision is associated with minimal scleral show. The design of the upper blepharoplasty incision is associated with the least percentage of this complication.
The most sensitive clinical laboratory indicator able to confirm cerebrospinal fluid leakage is:
A. Comparison of suspected fluid glucose to patient’s serum glucose
B. Dipstick test utilizing glucose oxidase
C. Beta 2 transferrin level of suspected fluid
D. Comparison of protein and potassium levels of suspected fluid to nasal secretions and
serum levels
ANSWER: C
RATIONALE:
Beta 2 transferrin is found only in the brain and eyes. The patient’s CSF may be contaminated with blood and therefore mimic serum. The dipstick test is colorimetric and if contaminated with red blood, may alter the results. Again, CSF may be contaminated with nasal secretions or blood and thus mimic those fluids rather than CSF.
The end metabolic degradation byproducts of bioresorbable osseous fixaton devices (plates and screws) are: A. glycolic acid B. lactic acid C. carbon dioxide and water D. Acetic acid
ANSWER: C
RATIONALE:
Both homopolymer and copolymer products follow the same metabolic degradation pathway culminating in the citric acid cycle, ultimately ending with the production of carbon dioxide and water.