(A) Facial (VII)
(B) Glossopharyngeal (IX)
(C) Great auricular
(D) Mandibular
(E) Posterior auricular

The correct response is Option A.

The stylomastoid foramen is located anterior to the mastoid process and posterior to the styloid root. The facial nerve and stylomastoid artery pass through the stylomastoid foramen as they exit the temporal bone; from this point, the facial (VII) nerve gives off branches to sites throughout the face. The main trunk of the facial nerve supplies innervation to the posterior belly of the digastric muscle as it leaves the foramen and enters the parotid gland.

The glossopharyngeal (IX), vagus (X), and spinal accessory (XI) nerves and the internal jugular vein pass through the foramen jugulare. The mandibular nerve and accessory meningeal artery pass through the foramen ovale, which lies anteromedial to the foramen spinosum; the lesser petrosal nerve may also be transmitted through the foramen ovale.

The great auricular nerve is derived from the nerve roots of C2-3 and not from cranial nerves. It travels around the posterior border of the sternocleidomastoid muscle to innervate the skin of the mastoid area.

The posterior auricular nerve branches off from the facial nerve just after it passes through the stylomastoid foramen and supplies innervation to the skin behind the ear.

References
1. Baker DC. Facial paralysis. In: McCarthy JG, ed. Plastic Surgery. Philadelphia, Pa: WB Saunders Co; 1990;3:2237-2319.
2. Putz R, Pabst R, eds. Sobotta's Atlas of Human Anatomy. Baltimore, Md: Williams & Wilkins; 1997;1:43.
3. Williams PL, Warwick R, Dyson M, et al, eds. Gray's Anatomy. Edinburgh, Scotland: Churchill Livingstone, Inc; 1989:337-367.

Anesthesia of the nasal side wall is best accomplished through infiltration of which of the following nerves?

(A) Buccal
(B) Dorsal nasal
(C) Infraorbital
(D) Infratrochlear
(E) Zygomaticofacial

The correct response is Option C.

The infraorbital nerve, which is the terminal branch of the maxillary division of the trigeminal nerve (V2), supplies sensation to the nasal side wall, ala, upper lip, lower eyelid, and medial aspect of the upper cheek. Anesthesia of this nerve is best accomplished by introducing the needle just lateral to the nasal ala and directing it to a point 0.5 cm below the central section of the infraorbital rim, directly into the foramen rotundum.

The buccal nerve is a branch of the mandibular division of the trigeminal nerve (V3). It arises from the surface of the buccinator muscle to supply sensation to the central cheek. Appropriate anesthesia is achieved by injecting the nerve at its origin on the mandibular nerve between the sigmoid notch of the mandible and lateral pterygoid plate.
The dorsal nasal nerve and infratrochlear nerve are branches of the nasociliary nerve, which is derived from the ophthalmic division of the trigeminal nerve (V1). The dorsal nasal nerve branches from the anterior ethmoidal nerve, then emerges at the distal end of the nasal bones to supply sensation to the skin of the dorsal nose from that point distally to the nasal tip. The infratrochlear nerve supplies sensation to the skin of the root of the nose and medial upper eyelid.

The zygomaticofacial nerve is a branch of the zygomatic nerve, which is derived from the maxillary division of the trigeminal nerve (V2). It emerges through one or two foramina just lateral to the infraorbital rim and supplies sensation to the skin over the zygoma and upper portion of the central cheek.

References
1. Moore KL, Dailey AF. Summary of cranial nerves. In: Moore KL, Dailey AF, eds. Clinically Oriented Anatomy. 4th ed. Philadelphia, Pa: Lippincott Williams & Wilkins; 1999:1082-1096.
2. Zide BM, Swift R. How to block and tackle the face. Plast Reconstr Surg. 1998;101:840-851.

Which of the following muscles acts to elevate the mandible?

(A) Anterior digastric
(B) Buccinator
(C) Lateral pterygoid
(D) Medial pterygoid
(E) Posterior digastric

The correct response is Option D.

Knowledge of the muscles of the mandibular region and their functions in the movement of the mandible and displacement of fracture segments is crucial to accurately diagnosing and effectively treating facial fractures.

Contraction of the medial pterygoid muscle elevates the mandible and pulls it medially. This muscle arises inferiorly, laterally, and posteriorly from the medial surface of the pterygoid plate and inserts on the medial ramus and mandibular angle. A patient who sustains a fracture medial to the mandibular angle has displacement of the mandibular ramus medially and cephalad because of the forces of this muscle.

The anterior belly of the digastric muscle originates from the inside lower border of the symphysis and attaches to the lateral corner of the hyoid bone, while the posterior belly of the digastric extends between the hyoid bone and mastoid notch of the temporal bone. The digastric muscle is part of the suprahyoid musculature, which in a patient with a mandibular fracture would pull the anterior mandibular fragments posteroinferiorly.

The buccinator muscle arises from the pterygomandibular raphae to insert into the orbicularis oris muscle and the mucosa and skin of the lips. This muscle of facial expression is innervated by the buccal branches of the facial nerve and acts to flatten the cheek against the teeth. Because it does not arise within the condylar region, it does not exert any forces on the condyle or mandible.
The lateral pterygoid muscle arises from the lateral pterygoid plate of the sphenoid bone and extends posteriorly and horizontally to insert on the neck of the condyle and into the anterior margin of the articular disk of the temporomandibular joint. As the condyle is moved forward, the lateral pterygoid acts to protrude the mandible, then slides down the articular eminence, opening the mouth. In patients with subcondylar fractures, the muscle pulls the condylar head in an anteromedial direction, whereas in patients with unilateral fractures the contralateral pterygoid continues to protrude, resulting in deviation of the mandible to the side of the fracture.

References
1. Dingman RO, Converse JM. The clinical management of facial injuries and fractures of the facial bones. In: Converse JM, ed. Reconstructive Plastic Surgery. Philadelphia, Pa: WB Saunders Co; 1977.
2. Hollinshead WH. The face. In: Anatomy for Surgeons: The Head and Neck. Philadelphia, Pa: Harper & Row; 1982:307.
3. Manson PN, Crawley WA, Yaremchuk MJ, et al. Midface fractures: advantages of immediate extended open reduction and bone grafting. Plast Reconstr Surg. 1985;76.1.

Which of the following branchial arches gives rise to the stylopharyngeus muscle?

(A) First
(B) Second
(C) Third
(D) Fourth
(E) Fifth

PHOTO

Reproduced with permission of Moore KL, ed. The Developing Human. 6th ed. Philadelphia, Pa: WB Saunders Co; 1998:220.

The correct response is Option C.
The stylopharyngeus is the only muscle derived from the third branchial arch. This muscle, which receives its innervation from the glossopharyngeal (X) nerve, is part of the intrinsic musculature of the larynx.

The muscles of mastication, the anterior belly of the digastric, the mylohyoid, the tensor tympani, and the tensor veli palatini are derived from the first branchial arch. These muscles are innervated by the trigeminal (V) nerve. The muscles of facial expression, the posterior belly of the digastric, the stylohyoid, and the stapedius are derived from the second branchial arch and are innervated by the facial (VII) nerve. The fourth branchial arch gives rise to the constrictor muscles of the pharynx, the cricothyroid, the levator veli palatini, the palatopharyngeus, and the palatoglossus. The superior laryngeal branch of the vagus (X) nerve supplies their innervation. The fifth branchial arch is only present in rudimentary forms and is often combined with the sixth branchial arch during any embryologic investigation. The intrinsic muscles of the larynx, except for the cricothyroid and stylopharyngeus, as well as the striated muscles of the esophagus are derivatives. These muscles are innervated by the recurrent laryngeal branch of the vagus (X) nerve.

References
1. Gosain AK, Moore FO. Embryology of the head and neck. In: Aston SJ, Beasley RW, Thorne CH, eds. Grabb & Smith's Plastic Surgery. 5th ed. Philadelphia, Pa: Lippincott-Raven; 1997:223-236.
2. Greene RM, Weston WM. Craniofacial embryology. In: Cohen M, ed. Mastery of Plastic and Reconstructive Surgery. Boston, Mass: Little, Brown & Co; 1994:459-470.
3. Moore KL, ed. The Developing Human. 6th ed. Philadelphia, Pa: WB Saunders Co; 1998:220.

The hamulus bone acts as a pulley for which of the following muscles?

(A) Levator veli palatini
(B) Palatoglossus
(C) Palatopharyngeus
(D) Superior pharyngeal constrictor
(E) Tensor veli palatini

The correct response is Option E.
The hamulus, which is an inferior extension of the medial pterygoid plate, acts as a pulley for the tensor veli palatini muscle. This muscle arises from the medial pterygoid plate and consolidates into a tendon that changes course as it wraps around the hamulus, and then extends medially to form an aponeurosis in the anterior soft palate. The tensor veli palatini also inserts on the posterior hard palate.

The levator veli palatini muscle arises from the inferior surface at the apex of the petrous portion of the temporal bone, and then passes obliquely downward and medially to join fibers from the contralateral muscle in forming the palatine velum. This muscle primarily acts to move the palate. A fibrous linkage exists between the fibers of the levator veli palatini and the tensor veli palatini; therefore, a patient who sustains a fracture of the pterygoid hamulus may have increased medial displacement of these muscles.

The palatoglossus muscle arises from the soft palate and courses downward within the anterior tonsillar pillar to insert into the tongue.

The palatopharyngeus muscle arises from the soft palate, coursing down the posterior tonsillar arch to join the stylopharyngeus, which then inserts on the thyroid cartilage. This muscle can be used for flap transfer in a patient undergoing sphincter pharyngoplasty for pharyngeal reconstruction.

The superior pharyngeal constrictor muscle arises from the posterior aspect of the medial pterygoid plate and from the hamulus, pterygomandibular raphe, and alveolar process of the mandible. The fibers of this muscle wrap around the pharynx and insert on the median raphe to form Passavant's ridge, which contributes to velopharyngeal closure.

References
1. Clemente CD, ed. Anatomy: A Regional Atlas of the Human Body. 4th ed. Baltimore, Md: Williams & Wilkins; 1997:739, 782, 845, 859, 872, 888, 895, 896.
2. Clemente CD, ed. Gray's Anatomy. 30th ed. Philadelphia, Pa: Lea & Febiger; 1985:443-461.

The internal carotid artery supplies which of the following arteries of the scalp?

(A) Frontalis
(B) Occipitalis
(C) Parietal
(D) Posterior auricular
(E) Supraorbital

The correct response is Option E.

The supraorbital and supratrochlear arteries are branches of the internal carotid artery via the ophthalmic artery and, therefore, receive their blood supply from the internal carotid. The arteries of the scalp travel through the subcutaneous fat from the periphery toward the vertex, then anastomose in the midline with branches of the ophthalmic artery. If the internal carotid artery is thrombosed, branches of the external carotid arteries supply blood to the anterior part of the scalp through the angular and ophthalmic arteries.

The frontalis and parietal arteries are branches of the superficial temporal artery, which in turn branches from the external carotid arteries. The occipitalis and posterior auricular arteries are also branches of the external carotid arteries.

References
1. Clemente C. Anatomy: A Regional Atlas of the Human Body. 2nd ed. Baltimore, Md: Urban & Schwarzenberg; 1981.
2. Janfaza P, Nadol JB. Scalp, cranium and brain. In: Janfaza P, Nadol JB, Galla RJ, et al, eds. Surgical Anatomy of the Head and Neck. Philadelphia, Pa: Lippincott Williams & Wilkins; 2001.

The levator palpebrae superioris muscle originates from which of the following structures?

(A) Annulus tendineus
(B) Bulbar fascia
(C) Ethmoid bone
(D) Frontal bone
(E) Sphenoid bone

The correct response is Option E.

The seven ocular muscles in the orbit are the levator palpebrae superioris, the superior and inferior oblique, and the superior, inferior, medial, and lateral recti. The rectus muscles and the superior oblique arise from the fibrous ring around the optic nerve (the annulus tendineus communis). In contrast, the inferior oblique arises from the maxilla, while the levator palpebrae superioris arises from the lesser wing of the sphenoid bone.

References
1. Clemente CD, ed. Anatomy: A Regional Atlas of the Human Body. 4th ed. Baltimore, Md: Williams & Wilkins; 1997:803-816.
2. Clemente CD, ed. Gray's Anatomy. 30th ed. Philadelphia, Pa: Lea & Febiger; 1985:1303-1307.

Which of the following structures is derived from the second branchial arch?

(A) Incus
(B) Malleus
(C) Sphenoid (greater wing)
(D) Stapes
(E) Temporal bone (squamous portion)

The correct response is Option D.

The stapes is derived from Reichert's cartilage, which is the precursor of the second branchial arch. Other structures derived from the second branchial arch include the stylohyoid process, the lesser cornu of the hyoid bone, and the upper part of the body of the hyoid bone.

The other two ossicles of the middle ear (malleus and incus) are derived from the first branchial arch. Cartilage precursors in the first branchial arch are the quadrate cartilage and Meckel's cartilage, both of which give rise to skeletal elements through endochondral ossification. The quadrate cartilage gives rise to the greater wing of the sphenoid bone and the incus, while Meckel's cartilage gives rise to the malleus and the mandibular condyles.

The skeletal elements of the maxillary and mandibular prominences originate from intramembranous ossification, which is derived from direct ossification of the dermal mesenchyme of the arches. The maxillary prominence gives rise to the maxilla, zygoma, and squamous portion of the temporal bone. The mandibular prominence gives rise to the body and ramus of the mandible.
References
1. Gosain AK, Moore FO. Embryology of the head and neck. In: Aston SJ, Beasley RW, Thorne CH, eds. Grabb & Smith's Plastic Surgery. 5th ed. Philadelphia, Pa: Lippincott-Raven; 1997:223-236.
2. Greene RM, Weston WM. Craniofacial embryology. In: Cohen M, ed. Mastery of Plastic and Reconstructive Surgery. Boston, Mass: Little, Brown & Co; 1994:459-470.
3. Moore KL, ed. The Developing Human. 4th ed. Philadelphia, Pa: WB Saunders Co; 1988:170-206.

Which of the following structures drains into the inferior meatus?

(A) Anterior ethmoid air cells
(B) Frontal sinus
(C) Maxillary sinus
(D) Nasolacrimal duct
(E) Sphenoid sinus

The correct response is Option D.

Knowledge of the anatomy of the sinuses is important in the management of patients who have fractures of the frontal sinus. Patency of the drainage system, including the frontonasal and nasolacrimal ducts, must be assessed, as occlusion of the ducts may result in the development of infection or mucocele.

The nasolacrimal duct drains into the inferior meatus. In contrast, the anterior ethmoid air cells and maxillary sinus drain into the middle meatus; the frontal sinus also drains into the middle meatus via the frontonasal duct. The sphenoid sinus drains into the sphenoethmoid recess, which is found above and behind the superior concha.

References
1. Gray H. Gray's Anatomy. 37th ed. Edinburgh, Scotland: Churchill Livingstone, Inc; 1989:182.
2. Hollinshead WH. The face. In: Anatomy for Surgeons: The Head and Neck. Philadelphia, Pa: Harper & Row; 1982:307.

A patient sustains a laceration of the superior helix of the auricle. Adequate anesthesia is most likely to be obtained with block of which of the following nerves?

(A) Facial (VII)
(B) Glossopharyngeal (IX)
(C) Great auricular
(D) Trigeminal (V)
(E) Vagus (X)

PHOTO

Reproduced with permission of Moore KL, ed. Clinically Oriented Anatomy. 3rd ed. Baltimore, Md: Williams & Wilkins; 1992:862.

The correct response is Option D.

Adequate anesthesia is most likely to be obtained with a block of the auriculotemporal nerve, which is a branch of the trigeminal (V) nerve that supplies sensation to the superior aspect of the helix. Sensory innervation to the entire ear is provided by the trigeminal (V), facial (VII), glossopharyngeal (IX), and vagus (X) nerves, as well as the second and third cervical nerves (C2 and C3). More specifically, the auriculotemporal branch of the trigeminal (V) nerve, tympanic branch (Jacobson's nerve) of the glossopharyngeal (IX) nerve, auricular branch (Arnold's nerve) of the vagus (X) nerve, lesser occipital nerve from C2, and great auricular nerve from C2 and C3 are directly involved in the innervation of the ear. The concha is innervated by the facial (VII), glossopharyngeal (IX), and vagus (X) nerves. The auriculotemporal nerve, as well as C2 and C3, supply sensation to the outer portions of the ear.

References
1. Lambert PR, Canalis RF. Anatomy and embryology of the auditory and vestibular systems. In: Canalis RF, Lambert PR, eds. The Ear: Comprehensive Otology. Philadelphia, Pa: Lippincott Williams & Wilkins; 2000:17-53.
2. Moore KL, ed. Clinically Oriented Anatomy. 3rd ed. Baltimore, Md: Williams & Wilkins; 1992:862.
3. Preuss S, Erickson E. Prominent ears. In: Achauer BM, Erikson E, Guyron B, et al, eds. Plastic Surgery: Indications, Operations, and Outcomes. Saint Louis, Mo: Mosby Ð Year Book, Inc; 2000;2:1057-1065.

Which of the following anatomic structures of the ear originates from the second (hyoid) pharyngeal arch?

(A) Antitragus
(B) Helical root
(C) Superior helix
(D) Tragus

The correct response is Option A.

During the sixth week of fetal gestation, the anatomic subunits of the auricle arise from six hillocks that are derived from the first and second pharyngeal arches. The anterior three hillocks from the first (or mandibular) pharyngeal arch ultimately develop into the tragus, helical root, and superior helix. The antihelix, antitragus, inferior helix, and lobule form from the fourth through sixth posterior hillocks from the second (or hyoid) pharyngeal arch. The structures that arise from the first pharyngeal arch typically drain into the parotid lymph nodes, and structures from the second pharyngeal arch drain into the cervical lymph nodes.

References
1. Brent B. Reconstruction of the auricle. In: McCarthy JG, ed. Plastic Surgery. Philadelphia, Pa: WB Saunders Co; 1990;3:2094.
2. Ruberg R, Smith D. Plastic Surgery: A Core Curriculum. Saint Louis, Mo: CV Mosby Co; 1994:251.