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O,I,N,A - Anatomy Lab

Origin, insertion, nerve innervation and action for Anatomy Lab Practical 1
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Subclavius
O: junction of 1st rib and its costal cartilage
I: subclavian groove of clavicle
N: nerve to Subclavius (C5,C6)
A: anchors and depresses the clavicle
Upper Trapezius
O: Medial third of superior nuchal line, external occipital protuberance, nuchal ligament, and SP C7
I: lateral third of acromion and clavicle
N: CN XI spinal accessory nerve and VR C3,C4
A: elevates, adducts, and upwardly rotates scapula
Middle Trapezius
O:SP T1-T5
I:Medial margin of acromion and superior lip of spine of scapula
N:CN XI spinal accessory nerve and VR C3,C4
A: Adduct the scapula
Lower Trapezius
O: SP T6-T12
I: tubercle at apex of spine of scapula
N:CN XI spinal accessory nerve and VR C3,C4
A: depresses, adducts, upwardly rotates scapula
Latissimus Dorsi
O: SP T7-T12, thoracolumbar fascia, iliac crest, and inferior 4 ribs.
I: floor of intertubercular groove of the humerus
N: Thoracodorsal nerve (C6,C7,C8)
A: extends, adducts, internally rotates humerus
Rhomboid Major
o: SP T2-T5
i: medial border of scapula from level of spine to inferior angle
N: Dorsal Scapular Nerve C4,C5
A: elevates, adducts, downwardly rotates scapula
Rhomboid Minor
o: nuchal ligament, SP C7,T1
i: medial border of scapula at root of spine of scapula
n: Dorsal scapular nerve C4,C5
a: elevates, adducts, downwardly rotates scapula
Levator Scapulae
o: posterior tubercles of TP C1-C4
i: medial border of scapula superior to root of scapular spine
n: dorsal subscapular nerve C5 and VR C3,C4
a: elevates, downwardly rotates the scapula
Serratus Anterior
o: external surfaces of lateral parts of 1st-8th ribs.
i: anterior surface of medial border of scapula
n: long thoracic nerve C5,C6,C7
a: abducts and upwardly rotates scapula; stabilizes medial border of scapula against thoracic wall
Coracobrachialis
o: Tip of coracoid process of scapula
i: middle third of medial surface of humerus
n: musculocutaneous C5,C6,C7
a: adducts and flexes the shoulder
Biceps Brachii
o: long head: supraglenoid tubercle and superior labrum
short head: coracoid process of scapula
i:radial tuberosity and fascia of the forearm via bicipital aponeurosis
n: musculocutaneous C5,C6,C7
a: shoulder flexion, elbow flexion, forearm supination
Anterior Deltoid
o: lateral third of clavicle
i: deltoid tuberosity of the humerus
n: axillary never C5,C6
a: flexes and internally rotates shoulder
Middle Deltoid
o: acromion
i: deltoid tuberosity of the humerus
n: axillary never C5,C6
a: abducts the shoulder
Posterior Deltoid
o: spine of scapula
i: deltoid tuberosity of the humerus
n: axillary never C5,C6
a: extends, externally rotates humerus
Teres Major
o: posterior surface of inferior angle of scapula
i: medial lip of intertubercular groove of the humerus
n: lower subscapular nerve C5,C6
a: extends, internally rotates, adducts humerus
Teres Minor
o: middle part of lateral border of scapula
i:inferior facet of greater tubercle of humerus
n: axillary nerve C5,C6
a. externally rotates humerus, depresses and compresses humeral head in glenoid
Supraspinatus
o: supraspinous fossa of scapula
i: superior facet of greater tubercle of humerus
n: suprascapular nerve C4,C5,C6
a: abducts humerus, depresses and compresses humeral head in glenoid
Infraspinatus
o: infraspinous fossa of scapula
i: middle facet of greater tubercle of humerus
n: suprascapular nerve C5,C6
a: externally rotates humerus, depresses and compresses humeral head in glenoid
Subscapularis
o:subscapular fossa
i: lesser tubercle of humerus
n: upper and lower subscapular nerves C5,C6,C7
a: internally rotates humerus, depresses and compresses humeral head in glenoid
Pectoralis Major
o: clavicular head:anterior surface of medial half of clavicle
sternocostal head: anterior surface of sternum, superior 6 costal cartilages, and aponeurosis of external oblique muscle.
i: lateral lip of intertubercular groove of humerus.
n: Lateral and medial pectoral nerves C5-T1
a: adducts and internally rotates humerus
Pectoralis Minor
o: 3rd-5th ribs near their costal cartilages
i: coracoid process of scapula
n: medial pectoral nerve C8,T1
a:stabilizes scapula by drawing it inferiorly and anteriorly against thoracic wall.
Brachialis
o:distal 1/2 of anterior surface of humerus
i: coronoid process and ulnar tuberosity
n: musculocutaneous C5,C6 and radial C5,C6,C7
a: flexes elbow
Triceps Brachii
o: long head: infraglenoid tubercle
lateral head: posterior surface of humerus superior to spiral (radial) groove
medial head: posterior surface of humerus inferior to spiral (radial) groove
i: olecranon process and fascia of forearm
n: radial C7,C8
a: elbow extension
Brachioradialis
o:proximal 2/3 of lateral supracondylar ridge of humerus
i: lateral surface of distal end of radius proximal to styloid process
n: radial C5,C6,C7
a: elbow flexion (maximal contribution with hand in mid-pronated position)
Multifidus
O: sacrum, transverse processes of C3-L5
I: spinous processes 2-4 vertebral levels superior to their origin
N: dorsal primary rami of spinal nerves C1-L5
A: Bilaterally: Extension of vertebrae.
Unilaterally: Contralateral rotation
Erector spinae
O: iliac crest, sacrum, transverse and spinous processes of vertebrae and supraspinal ligament
I: angles of the ribs, transverse and spinous processes of vertebrae, posterior aspect of the skull
N: segmentally innervated by dorsal primary rami of spinal nerves C1-S5
A: extends and laterally bends the trunk, neck and head
Iliocostalis
O: posterior iliac crest of os coxa;
I: posterior angle of ribs
N: dorsal primary rami of spinal nerves C4-S5
A: extends and laterally bends the trunk and neck
Interspinales
O: upper border of spinous process
I: lower border of spinous process above
N: dorsal primary rami of spinal nerves C1-L5
A: extend trunk and neck
Intertransversarii
O: upper border of transverse process
I: lower border of transverse process above
N: Posterior rami of spinal nerves
• A: Unilateral: Aid in lateral flexion of vertebral column
• A: Bilateral: Stabilize vertebral column
Longissimus
O: Posterior iliac crest, post sacrum, sacroiliac ligaments, sacral and lower lumbar spinous processes, and supraspinous ligament
I: Medial/inferior of all ribs between tubercles, mastoid process, TP of C1-C7
N: Posterior rami of spinal nerves
A: Bilaterally-extend back and neck, control eccentric contraction
Unilaterally-laterally flex vertebral column
Semispinalis
O: transverse processes of C7-T12
I: capitis: back of skull between nuchal lines; cervicis & thoracis: spines 4-6 vertebrae above origin
N: dorsal primary rami of spinal nerves C1-T12
A: extends the trunk and laterally bends the trunk, rotates the trunk to the opposite side
Rotatores
O: Transverse processes of vertebrae
I: Junction of lamina and spinous processes
Brevis-spinous process of vertebrae, immediately superior
Longus-spinous process of vert 2 superior
N: Posterior rami of spinal nerves
A: Stabilize, assist with local extension and rotation, propioception
Levatores costae (longus and brevis)
O: Transverse process C7-T11.
I: Subjacent ribs between tubercle and angle.
N: dorsal rami of spinal nerves C8-T11
A: Elevate ribs for deep inspiration
Sternocleidomastoid
O: two heads 1) Sternum - manubrium 2) clavicle - medial 1/3
I: both heads to temporal bone - Mastoid process
N: Accessory n. (XI)
A: bilateral - flex neck; unilateral - rotate head so face is directed to opposite side
anterior scalene
O: anterior tubercles of the transverse processes of vertebrae C3-C6
I: scalene tubercle of the first rib
N: brachial plexus, C5-C7
A: elevates the first rib; flexes and laterally bends the neck
middle scalene
O: posterior tubercles of the transverse processes of vertebrae C2-C7
I: upper surface of the first rib behind the subclavian artery
N: brachial plexus, C3-C8
A: elevates the first rib; flexes and laterally bends the neck
Omohyoid
O: inferior belly: upper border of the scapula medial to the scapular notch; superior belly: intermediate tendon

I: inferior belly: intermediate tendon; superior belly: lower border of the hyoid bone lateral to the sternohyoid insertion
A: depresses/stabilizes the hyoid bone
N: ansa cervicalis
Sternohyoid
O: posterior surfaces of both the manubrium and sternal end of the clavicle
I: lower border of the hyoid bone, medial to the omohyoid m. insertion
N: Ansa cervicalis
A: depress hyoid bone
Sternothyroid
O: posterior surface of the manubrium below the origin of the sternohyoid m.
I: oblique line of the thyroid cartilage
N: ansa cervicalis
A:depresses/stabilizes the hyoid bone
Thyrohyoid
O: oblique line of the thyroid cartilage
I: lower border of the hyoid bone
N: ansa cervicalis (via fibers running with the hypoglossal nerve that leave XII distal to the superior limb of ansa)
A: elevates the larynx; depresses/stabilizes the hyoid bone
Digastric (has 2 bellies)
O: Posterior belly from temporal bone - mastoid notch (medial to mastoid process); Anterior belly from Mandible -inner side
I: Hyoid bone via intermediate tendon
N: Posterior belly - Facial nerve (VII); Anterior belly - Trigeminal nerve (V)
A: Elevates hyoid bone; depresses mandible
Stylohyoid
O: Temporal bone (styloid process)
I: Hyoid bone
N: Facial n. (VII)
A: Elevates hyoid bone
Mylohyoid
O: Mandible - mylohyoid line
I: Hyoid bone
N: Trigeminal nerve (V)
A: Elevates hyoid bone, Raises floor of mouth during swallowing
Geniohyoid
O: Mandible (inferior mental spine)
I: Hyoid bone
N: Anterior ramus of C1 (via CN XII)
A: Elevates hyoid bone, draws hyoid forward
Platysma
O: subcutaneous tissue of infraclavicular and supraclavicular regions
I: Mandible (inferior border), skin over lower face and angle of mouth
N: Cervical branch of facial n. (VII)
A: Depresses and wrinkles skin of lower face and mouth, tenses skin of neck, aids forced depression of mandible