Functional anatomy exam 3 (shoulder & elbow)

what is the pectoral girdle?

an incomplete ring formed by the clavicle and scapula

what is the purpose of the pectoral girdle?

connect the bones of the upper limbs to the axial skeleton

bones of the shoulder joint

scapula, clavicle, humerus, sternum

what is odd about the coracoacromial ligament and transverse humeral ligament

both ligaments have both attachments on the same bone, THL holds tendon in place

how many distinct bands does the anterior glenohumeral joint have and what are they?

3 - superior, middle, inferior

what plane does the glenohumeral joint IR occur

transverse

which shoulder joint is the only functional joint (aka false joint)?

scapulothoracic

what are the motions of the scapulothoracic joint?

-elevation & depression

-protraction (abd) & retraction (add)

-upward & downward rotation

what are the anterior muscles of the pectoral girlde?

-subclavius

-pectoralis minor

-serratus anterior

origin and insertion of the subclavius

O- junction of the first rib and costal cartilage

I- inferior surface of middle 1/3 of clavicle

action of subclavius

depression of clavicle

innervation of subclavius

cervical nerves 5 & 6

origin and insertion of the pectoralis minor

O- 3rd-5th ribs near the costal cartilage

I- coracoid process

action of pec minor

scapular depression and protraction

pec minor innervation

Medial pectoral nerve

origin and insertion of the serratus anterior

O- external surface of ribs 1-8

I- medial border of scapula

action of serratus anterior

scapular protraction & upward rotation

serratus anterior innervation

long thoracic nerve

sections of the trapezius

upper, middle, lower

trapezius origin and insertion

O- occipital bone

ligamentum nuchae

spinous processes C7-T12

I- lateral 1/3 of clavicle & spine of scapula

action of trapezius

upper- scapular elevation

middle- scapular retraction

lower- scapular depression

also neck extension

trapezius innervation

spinal accessory nerve (cranial nerve 11)

origin and insertion of levator scapulae

O- transverse processes of C1-C4

I- medial superior scapula

action of levator scapulae

scapular elevation & scapular upward rotation

innervation of levator scapulae

dorsal scapular nerve

origin of rhomboid major and minor

major- spinous process of T2-T5

minor- spinous process of C7-T1

insertion of rhomboid major and minor

medial border of the scapula

innervation of rhomboid major and minor

dorsal scapular nerve

actions of rhomboid major and minor

Scapular retraction and downward rotation

muscles of the rotator cuff

supraspinatus, infraspinatus, teres MINOR, subscapularis

supraspinatus origin and insertion

O- supraspinous fossa

I- greater tubercle of humerus

action of supraspinatus

-pull humeral head into glenoid

-GH abduction to 30 degrees

-GH ER

origin and insertion of infraspinatus

O- infraspinous fossa

I- greater tubercle

action of infraspinatus

-pull humeral head into glenoid

-GH ER

innervation of supraspinatus and infraspinatus

suprascapular nerve

origin of subscapularis

subscapular fossa of scapula

insertion of subscapularis

lesser tubercle of humerus

action of subscapularis

-GH IR

-GH adduction

-pulls humeral head into glenoid fossa

innervation of subscapularis

subscapular nerve

what is the only rotator cuff muscle to insert on the lesser tubercle instead of greater tubercle?

subscapularis

what is the only rotator cuff muscle to produce GH internal rotation?

subscapularis

origin and insertion of teres minor

O- lateral border of scapula

I- greater tubercle

teres minor action

-GH ER

-pulls humeral head into glenoid fossa

innervation of teres minor

axillary nerve

what is the only rotator cuff muscle on the anterior aspect?

subscapularis

anterior muscles that move the humerus

pectoralis major, deltoid, coracobrachialis, biceps brachii

what are the three sections of the deltoid

anterior, middle, posterior

origin of deltoid

A- later 1/3 of the clavicle

M- acromion process

P- spine of scapula

deltoid insertion

deltoid tuberosity

innervation of deltoid

axillary nerve

actions of deltoid

A- GH flexion, IR, horizontal adduction

M- Gh abduction

P- GH extension, ER, horizontal abduction

what are the two heads of the pec major

clavicular and sternal

origin of pectoralis major

C- medial 1/2 of clavicle

S- sternum and costal cartilages 2-4

insertion of pectoralis major

lateral lip of intertubercular groove of humerus

actions of the pec major

Gh adduction, flexion, IR, and assisting GH horizontal adduction

pec major innervation

medial and lateral pectoral nerves

origin and insertion of coracobrachialis

O- coracoid process

I- medial 1/3 of humerus

action of coracobrachialis

GH flexion and adduction

coracobracialis innervation

musculocutaneous nerve

origin of biceps brachii

short- coracoid process

long- supraglenoid tubercle

insertion of biceps brachii

radial tuberosity (both heads)

actions of the biceps brachii

-elbow flexion

-forearm supinaiton

-GH flexion

innervation of biceps brachii

musculocutaneous nerve

posterior muscles that move the humerus

triceps brachii, teres MAJOR, latissimus dorsi

origin of lat dorsi

-spinous processes of T7-T12

-thoracolumbar fascia

-illiac crest

-inferior portion of sacrum

insertion of lat dorsi

intertubercular groove of humerus

innervation of lat dosri

thoracodorsal nerve

actions of lat dorsi

GH extension, adduction and IR

origin and insertion of teres major

O- inferior angle of scapula

I- intertubercular groove of humerus

actions of teres major

GH IR, extension, adduction

innervation of teres major

subscapular nerve

sections of the triceps

long, lateral and medial heads

origin of triceps brachii

-long- infraglenoid tubercle of scapula

-lateral- posterior humerus superior to radial groove

-medial- posterior humerus inferior to radial groove

insertion of triceps brachii

olecranon process of ulna

actions of the triceps brachii

elbow and shoulder extension

triceps brachii innervation

radial nerve

what is the purpose of the brachial plexus?

provides the neural supply to the upper extremities

what does the brachial plexus break down into?

roots, trunks, divisions, cords, branches

(real trainers drink cold beer)

what is the brachial plexus formed from?

ventral rami of C5-T1 nerve roots

what bones make up the elbow joint?

distal humerus

proximal ulna

proximal radius

what are the three elbow joints?

-humeroulnar

-humeroradial

-proximal radioulnar

what ligaments resist VARUS forces at the elbow?

radial (lateral) collateral ligament

what ligaments resist VALGUS forces at the elbow?

ulnar (medial) collateral ligament

what is unique about the annular ligament?

it surrounds the neck of the radius

what is the purpose of the interosseous membrane?

to help distribute forces from the distal RADIUS through the rest of the arm

what are the motions of the elbow?

flexion, extension, pronation, supination

what plane of motion does pronation and supination occur?

transverse

what plane of motion does flexion and extension at the elbow occur?

sagittal

anterior muscles of the elbow

biceps brachii, brachialis, brachioradialis, pronator teres

posterior muscles of the elbow

triceps brachii, anconeous

most common motion at the elbow produced by the anterior muscles

flexion

most common motion at the elbow produced by the posterior muscles

extension

what is the carrying angle?

angle between humerus and forearm in the frontal plane

cubitus varus (carrying angle)

angle smaller than normal

cubitus valgus (carrying angle)

angle larger than normal (vaLgus=Larger)

origin and insertion of brachioradialis

O- supracondylar ridge of humerus

I- lateral styloid process of radius

actions of brachioradialis

elbow flexion, assist in pronation & supination

brachioradialis innervation

radial

origin and insertion of brachialis

O- anterior surface of lower half of humerus

I- coronoid process of ulna

brachialis action

elbow flexion