Muscles for Skills Check August 2023

Question 1

Temporalis

Answer 1

O: Floor of Temporal fossa

I: Tip/medial surface of coronoid process and anterior boarder of ramus of mandible

N: CN V3

A: Elevates mandible, clinching teeth

Question 2

Masseter

Answer 2

O: Inferior boarder and medial surface of zygomatic arch

I: Angle and lateral surface of ramus of mandible

N: CN V3

A: Elevates mandible, clinching teeth

Question 3

Lateral pterygoid

Answer 3

O: One head - infratemporal surface and crest of greater wing of sphenoid
Second head - Lateral surface of lateral pterygoid plate

I: Superior head - primarily to TMJ joint capsule and articular disc
Inferior head - primarily to pterygoid fovea on anteromedial aspect of neck of condyloid process of mandible

N: CN V3

A: Acting bilaterally - protracts mandible and depresses chin
Unilaterally - swings jaw toward contralateral side

Question 4

Medial pterygoid

Answer 4

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

I: Medial surface of ramus of mandible; ipsilateral masseter

N: CN V3

A: Acts synergistically with masseter to elevate mandible; alternating unilateral activity produces smaller grinding motions

Question 5

Minor Rhomboid

Answer 5

O: Spinous process of C7 and T1

I: Smooth triangular area medial to scapular spine

N: Dorsal scapular nerve (C4, C5)

A: Retract scapula and rotate its glenoid cavity inferiorly

Question 6

Major Rhomboid

Answer 6

O: Spinous process of T2 - T5

I: Medial boarder of scapula from level of scapular spine to inferior angle

N: Dorsal scapular nerve (C4, C5)

A: Retracts scapula and rotates its glenoid cavity inferiorly