Back Muscles (O, I, A, Ns) Flashcards
Origin: trapezius

Skull - external occipital protuberance
Fasica - ligamentum nuchae
Vertebrae - Spine of C7, T1-T12
Insertion: trapezius

Clavicle - lateral 1/3
Scapula - acromion and spine
Action: trapezius
Both elevates and depresses shoulder
Retracts scapula
Extends neck
Nerve: trapezius
Accessory nerve (Cranial nerve XI)
Origin: Latissimus Dorsi

Vertebra - spines of T6-T12
Fasica - thoracolumbar fascia
Pelvic bone - iliac crest
Insertion: Latissimus Dorsi

Humerus - intertubercular groove
Action: Latissimus Dorsi
Adducts, extends, and medially rotates arm
Nerve: Latissimus Dorsi
Thoracodorsal N.
Origin: Levator Scapulae

Vertebrae - transverse processes of C1 - C4
Insertion: Levator Scapulae

Scapula - superior angle and medial border
Action: Levator Scapulae
elevates and abducts scapula
Nerve: Levator Scapulae
Dorsal Scapular nerve
Origin: Rhomboid minor

Vertebrae - spines of C7, T1
Insertion: Rhomboid minor

Scapula - medial border
Action: Rhomboid minor
Elevates and abducts scapula
Nerve: Rhomboid minor
Dorsal Scapular nerve
Origin: Rhomboid major

Vertebra - spines of T2-T5
Insertion: Rhomboid major

Scapula - medial border to inferior angle
Action: Rhomboid major
Elevates and adducts scapula
Nerve: Rhomboid major
Dorsal Scapular nerve
Origin: Teres major

Dorsal surface of the inferior angle of the scapula
Insertion: Teres major

Crest of the lesser tubercle of the humerus
Action: Teres major
Internal rotation, adduction and extension of the arm
Nerve innervation: Teres major
Axillary nerve (C5, C6)
Origin: Teres minor

Upper two-thirds of the lateral margin of the scapula
Insertion: Teres minor

Greater tubercle of the humerus
Action: Teres minor
External rotation and adduction of the arm
Nerve innervation: Teres minor
Lower subscapular nerve
Origin: Levator Costarum
Vertebrae - process of C7, T1 - T11
Insertion: Levator Costarum
Ribs - inferior to origin
Action: Levator Costarum
Raises ribs in inspiration
Nerve: Levator Costarum
Dorsal rami of thoracic spinal nerves
Origin: Serratus posterior superior

Vertebrae - spines of the cervical and upper thoracic vertebrae
Insertion: Serratus posterior superior

Ribs
Action: Serratus posterior superior
Raises ribs in inspiration
Nerve: Serratus posterior superior
Intercoastal nerves
Origin: Serratus posterior inferior

Vertebrae - spines of upper lumbar and lower thoracic vertebrae
Insertion: Serratus posterior inferior

Ribs
Action: Serratus posterior inferior
Lowers ribs in exhalation
Nerve: Serratus posterior inferior
Intercoastal nerves
Origin: infraspinatus

Medial three quarters of infraspinous fossa of scapula and fibrous intermuscular septa
Origin: supraspinatus

Medial three quarters of supraspinous fossa of scapula, upper surface of spine
Insertion: Infraspinatus

Middle facet of greater tuberosity of humerus and capsule of shoulder joint
Action: Infraspinatus
Laterally rotates arm and stabilizes shoulder joint
Nerve: Infraspinatus
Suprascapular nerve (C5, 6 ) (from upper trunk)
Action: Supraspinatus
Abducts arm and stabilizes shoulder jnt
Insertion: Supraspinatus

Superior facet on greater tuberosity of humerus and capsule of shoulder joint
Nerve: Supraspinatus
Suprascapular N (C5, 6)(from upper trunk)
Origin: Splenius
Vertebra - spines of T1 - T4
Insertion: Splenius
Splenius capitis to skull - occipital and temporal bones
Splenius cervicis to vertebrae - transverse processes of C2 - C3
Action: Splenius
Extend neck and head (rotate in unilateral action)
Nerve: Splenius
Dorsal rami of spinal nerves
Origin: Erector Spinae
Iliocostalis
Sacrum, the illiac crest
Insertion: lIiocostalis
lIiocostalis to ribs and transverse processes
Action: IIiocostalis
Extend trunk and vertebral column
Nerve: lIiocostalis
Dorsal rami of spinal nerves
Origin: Longissimus

Logngissisum from transeverse process of vertebra
Insertion: Longissimus

Longissimus to transvers process of vertebrae
Action: Longissimus
Extend trunk and vertebral column
Nerve: Longissimus
Dorsal rami of spinal nerves
Origin: Spinalis

Spinalis from spinous process
Insertion: Spinalis

Spinous processes six levels above
Action: Spinalis
Extend trunk and vertebral column
Nerve: Spinalis
Dorsal rami of spinal nerves