Superficial (appendicular) group of back muscles

Question 1

Trapezius

Answer 1

Origin:

• Superior nuchal line
• External occipital protuberance
• Ligamentum nuchae
• Spinous processes of C7 to T12

Insertion:

• Lateral one third of the clavical
• Acromion
• Spine of the scapula

Innervation:

• Motor - accessory nerve [XI]
• Proprioception C3 and C4

Function:

• Assists in rotating the scapula during abduction of humerus above horisontal
• Upper fibres elevate, middle fibres adduct, lower fibres depress scapula

Question 2

Latissimus dorsi

Answer 2

Orgin:

• Spinous processes of T12 to L5 and sacrum
• Iliac crest
• Ribs 10 to 12

Insertion:

• Floor of intertubercular sulcus of humerus

Innervation:

• Thoracodorsal nerve

Function:

• Extends, adducts and medially rotates humerus

Question 3

Levator scapulae

Answer 3

Origin:

• Transverse processes of C1 to C4

Insertion:

• Upper portion of medial border of scapula

Innervation:

• C3 to C4
• Dorsal scapular nerve

Function:

• Elevates scapula

Question 4

Rhomboid major

Answer 4

Origin:

• Spinous processes of T2 to T5

Insertion:

• Medial border of scapula between spine and inferior angle

Innervation:

• Dorsal scapular nerve

Function:

• Retracts (adducts) and elevates scapula

Question 5

Rhomboid minor

Answer 5

Origin:

• Lower portion of ligamentum nuchar
• Spinous processes of C7 and T1

Insertion:

• Medial border of scapula at spine of scapula

Innervation:

• Dorsal scapula nerve

Function:

• Retracts (adducts) and evelates scapula