Head and Neck

Question 1

Sternocleidomastoid

Answer 1

O: Sternal head – upper part of anterior surface of manubrium of sternum
Clavicular head – superior surface of medial one-third of clavicle

I: Lateral one-half of superior nuchal line and lateral surface of mastoid process

A: Unilaterally: Laterally flex the head and neck to same side, Rotate the head and neck to opposite side
Bilaterally: Flex the neck, Assist to elevate the ribcage during inhalation

N: Accessory nerve (CN XI) and branches from anterior rami C2, C3 (C4)

Question 2

Anterior Scalene

Answer 2

O (superior attachment): Anterior tubercle of transverse processes of 3rd to 6th cervical vertebrae

I: Scalene tubercle and upper surface of 1st rib 

A: Unilaterally: With the ribs fixed, laterally flex the head and neck to the same side and rotate head and neck to the opposite side
Bilaterally: Elevation of 1st rib

N: anterior rami C4-C6

Question 3

Middle Scalene

Answer 3

O (superior attachment): Posterior tubercles of transverse processes of 2nd to 7th cervical vertebrae

I: Upper surface of 1st rib posterior to the groove for the subclavian artery

A: Unilaterally: With the ribs fixed, laterally flex the head and neck to the same side and rotate head and neck to the opposite side
Bilaterally: Elevation of 1st rib

N: Anterior rami of C3-C7

Question 4

Posterior Scalene

Answer 4

O (superior attachment): Posterior tubercle of transverse processes of 4th to 6th cervical vertebrae

I: Upper surface of 2nd rib

A: Unilaterally: With the ribs fixed, laterally flex the head and neck to the same side and rotate head and neck to the opposite side
Bilaterally: Elevation of 2nd rib

N: Anterior rami of C7-C8

Question 5

Longus colli

Answer 5

O (inferior attachment): Anterior bodies of C5-T3; Transverse processes of C3-C5 (some texts describe different parts of this muscle, we will review in lecture)

I (superior attachment): Anterior tubercle of C1; bodies of C1-C3, transverse processes of C3-C6 (some texts describe different parts of this muscle, we will review in lecture)

A:Unilaterally: Laterally flex the head and neck to the same side, slight rotate the head and neck to the opposite side
Bilaterally: flex the head and neck

N: Branches from anterior rami of C2 – C6

Question 6

Longus capitis

Answer 6

O (inferior attachment): anterior tubercles of transverse processes of 3rd to 6th vertebrae

I (superior attachment): inferior surface of basilar part of occiput

A: Unilaterally: Laterally flex the head and neck to the same side, Rotate the head and neck to the same side
Bilaterally: Flex the head and neck

N: Branches from anterior rami of C1 – C3

Question 7

Rectus capitis anterior

Answer 7

O: anterior surface of lateral part of atlas and its transverse process

I: inferior surface of basilar part of occipital bone

A: flexion of the head at the atlanto-occipital joint

N: branches from anterior rami of C1, C2

Question 8

Rectus capitis lateralis

Answer 8

O: superior surface of transverse process of atlas

I: inferior surface of jugular process of occipital bone

A: lateral flexion of the head to the same side

N: branches from anterior rami of C1, C2

Question 9

Rectus capitis posterior major

Answer 9

O: spinous process of axis (C2)

I: lateral portion of inferior nuchal line  

A: extension of the head; rotate the head to the same side

N: posterior ramus of C1, suboccipital n.

Question 10

Rectus capitis posterior minor

Answer 10

O: Tubercle of the posterior arch of atlas (C1)

I: medial portion of inferior nuchal line

A: extension of head

N: posterior ramus of C1, suboccipital n.

Question 11

Obliqus capitis superior

Answer 11

O: transverse process atlas (C1)

I: occipital bone between superior and inferior nuchal lines

A: extension of head; laterally flex the head to the same side

N: posterior ramus of C1 (suboccipital nerve)

Question 12

Obliqus capitis inferior

Answer 12

O: spinous process axis (C2)

I: transverse process atlas (C1)

A: rotation of face head to same side

N: posterior ramus of C1 (suboccipital nerve)

Question 13

Masseter

Answer 13

O: zygomatic arch and the maxillary process of the zygomatic bone

I: ramus of mandible & coronoid process

A: superficial fibers: elevation & protrusion of mandible (acting bilaterally); deep fibers: retrusion (acting bilaterally)

N:  massetric nerve from the anterior trunk of the mandibular branch of the trigeminal nerve CN V

Question 14

Temporalis

Answer 14

O: bone of temporal fossa and temporal fascia

I: coronoid process of mandible and anterior margin of ramus of mandible

A: elevation and retrusion of mandible

N: deep temporal nerves from anterior trunk of mandibular branch of the trigeminal nerve CN V

Question 15

Lateral pterygoid

Answer 15

O: Superior Head: Infratemporal surface and crest of greater sphenoid wing
Inferior Head: Lateral surface of lateral pterygoid plate of sphenoid bone

I: Capsule of temporomandibular joint, articular disc, and the pterygoid fovea on the neck of mandible

A: Deviates mandible to opposite side (i.e. contralateral lateral deviation, acting unilaterally), protrusion of the mandible (acting bilaterally), grinding (acting alternately), superior head: during elevation of the mandible it eccentrically contracts to control posterior glide of disc; inferior head: depression

N: Massetric nerve from the anterior trunk of the mandibular branch of the trigeminal nerve CN V

Question 16

Medial pterygoid

Answer 16

O: Deep head - medial surface of lateral pterygoid plate and pyramidal process of palatine bone
Superficial head - tuberosity and pyramidal process of maxilla

I: Medial surface of ramus of mandible, inferior to mandibular foramen

A: Elevation of mandible; deviates mandible to opposite side (i.e. contralateral lateral deviation; acting unilaterally), protrusion of the mandible (acting bilaterally), grinding (acting alternately)

N: Nerve to medial pterygoid from mandibular nerve CN V
     Nerve to lateral pterygoid directly from the anterior trunk of the mandibular nerve or from the 
 buccal branch