OIAN 10

Question 1

Trapezius (Upper, middle, lower)

Answer 1

Origin:
- External occipital protuberance
- Ligamentum nuchae
- Spinous processes of C1-T12
Insertion:
- Posterior, lateral portion of the clavicle
- Medial surface of the acromion
- Superior spine of the scapula
Action:
- Elevates the scapula (upper)
- Upwardly rotates the scapula (upper and lower)
- Downwardly rotates the scapula (lower)
- Retracts scapula (all)
Nerve:
- Motor: spinal accessory (XI Cranial)
- Sensory: ventral ramii of C3 and C4

Question 2

Latissimus Dorsi

Answer 2

Origin:
- Spinous process of T7-L5
- Iliac crest
- Inferior angle of the scapula
Insertion:
-Bicipital (intertubercular) groove of the humerus
Action:
- Adducts the arm
- Extends the arm (from a flexed position)
- Internally (medially) rotates the arm
- Downwardly rotates the scapula
Nerve:
- Thoracodorsal  (C6,7,8)

Question 3

Levator scapulae

Answer 3

Origin:
- Transverse processes of the upper 3 or 4 cervical vertebrae
Insertion:
- Superior angle of the scapula
Action:
- Elevates the scapula
- Extends and/or laterally flexes the neck
- Assists to downwardly rotate the scapula
Nerve:
- Dorsal scapular
C5

Question 4

Rhomboid minor

Answer 4

Origin:
- Spinous processes of C7 & T1
Insertion:
- Medial border of the scapula at the level of the spine
Action:
- Retracts the scapula
- Assists to downwardly rotate the scapula
- Eccentrically helps to control rate of scapular upward rotation during arm elevation.
Nerve:
- Dorsal scapular
C5

Question 5

Rhomboid major

Answer 5

Origin:
- Spinous processes of T2-T5
Insertion:
- Medial border of the scapula from below the spine
Action:
- Retracts the scapula
- Assists to downwardly rotate the scapula
- Eccentrically helps to control rate of scapular upward rotation during arm elevation.
Nerve:
- Dorsal scapular
C5