Back Muscles

Question 1

a. Iliocostalis Lumborum:

Answer 1

i. Origin: Iliac Crest
ii. Insertion: Angles of Ribs
iii. Action: Extend vertebral column
iv. Innervation: Dorsal Rami of Spinal Nerves

Question 2

Longissimus (Thoracis):

Answer 2

i. Origin: Transverse Processes of lumbar to cervical vertebrae
ii. Insertion: Transverse Processes of Superior Vertebrae
iii. Action: Extend vertebral column
iv. Innervation: Dorsal Rami of Spinal Neves

Question 3

Spinalis (Thoracis):

Answer 3

i. Origin: Spinous Processes
ii. Insertion: Spinous Processes superior vertebrae
iii. Action: extend vertebral column
iv. Innervation: Dorsal Rami of Spinal Nerves

Question 4

Latissimus Dorsi:

Answer 4

i. Origin: Spinous Processes of T7 to L5 and the iliac crest
ii. Insertion: Intertubercular Sulcus of Humerus
iii. Action: Adduct Arm
iv. Innervation: Thoracodorsal n.

Question 5

Levator Scapulae:

Answer 5

i. Origin: Transverse Processes of C1 to C4
ii. Insertion: Medial Boarder of the Scapula superior to the spine
iii. Action: Elevate Scapula
iv. Innervation: Dorsal Scapular n.

Question 6

Rhomboids

Answer 6

i.. Origin: Spinous Processes of C7 to T5
ii. Insertion: Medial Border of the scapula
iii. Action: Adduct Scapula
iv. Innervation: Dorsal Scapular n.

Question 7

Splenius Capitis

Answer 7

i. Origin: Spinous Processes of Upper Thoracic Vertebrae
ii. Insertion: Mastoid Process
iii. Action: Extend and hyperextend head
iv. Innervation: Dorsal Rami of spinal nerves

Question 8

Semispinalis Capitis

Answer 8

i. Origin: Transverse Processes of C6 to T12
ii. Insertion: Occipital Bone
iii. Action: Extend head
iv. Innervation: Dorsal Rami of Spinal Nerves

Question 9

Trapezius

Answer 9

i. Origin: Occipital bone and Spinous Processes of C7 to T12
ii. Insertion: Acromion and Spine of Scapula and lateral 1/3 of clavicle
iii. Action: Elevate Shoulders
iv. Innervation: Spinal Accessory Nerve CN XI