Back muscles flash cards

TRAPEZIUS Extrinsic superficial 1st layer of the back

Origin:
• Superior nuchal line
• Ligamentum nuchae
• Spinous processes C7 – T12

Insertion:
• Acromion process
• Superior border of spine of scapula
• Lateral 1/3rd of clavicle

Action:
• Retracts scapula
• Laterally rotates scapula
• Depresses & elevates scapula

LATISSIMUS DORSI Extrinsic superficial 1st layer of the back

Origin:
• Spinous processes T7 – L5
• Sacral iliac crest
• Inferior 4 ribs

Insertion:
• Intertubercular sulcus of the
humerus

Action:
• Adduction, extension, medial
rotation of the arm
• Moves arm inferiorly & posteriorly

, RHOMBOID MAJOR Extrinsic superficial 2nd layer of the back

Origin:
• Spinous processes T2 – T5

Insertion:
• Medial border of scapula inferior
to spine

Action:
• Stabilisation, adduction, elevation
& downward rotation of the
scapula

RHOMBOID MINOR Extrinsic superficial 2nd layer of the back

Origin:
• Spinous processes C7 – T1

Insertion:
• Medial border of scapula superior
to spine

Action:
• Stabilisation, adduction, elevation
& downward rotation of the
scapula

LEVATOR SCAPULA Extrinsic superficial 2nd layer of the back

Origin:
• Transverse processes C1 – C4

Insertion:
• Superior medial border of the
scapula

Action:
• Elevation & downward rotation of
the scapula