Superficial Back/Scapular/Shoulder/Pectoral

Intertubercular groove mnemonic

"The LADY between TWO MAJORS" - lady = latissimus doris on the floor of the groove - teres major is on the medial lip of the groove - pectoralis major is on the lateral lip

the breast is made of mammary tissue with _________ lobes supported by ___________ ligaments)

15 to 20, suspensory or cooper's

Breast extends from ___ to ___ intercostal space and the nipple is at the ____ intercostal space

2 to 6; 4th

pectoralis minor medial attachment

3rd-5th ribs near their costal cartilages

if the clavicle is fractured what happens to the subclavius

????

pectoralis major main action

Adducts and medially rotates humerus

serratus anterior origin

Anterior surfaces of the first 8 or 9 ribs

Deltoid innervation

Axillary nerve (C5, C6)

teres minor innervation

Axillary nerve (C5, C6)

A 35-year-old man is admitted to the emergency department after a severe car crash. While performing the physical examination the emergency medicine physician observes the patient cannot shrug his shoulders. Which of the following nerves is most likely injured? A. Long thoracic B. Axillary C. Spinal accessory D. Dorsal scapular E. Thoracodorsal

C: The spinal accessory nerve is the only nerve that innervates the trapezius and elevates /shrugs the shoulder. The long thoracic nerve innervates the serratus anterior muscle, which protracts and upwardly rotates the scapula. Persons with injury to this nerve will have their scapulae protrude on their back like a wing. The axillary nerve supplies the deltoid and teres minor muscles. The deltoid abducts, flexes, and extends while the teres minor laterally rotates the arm. The dorsal scapular nerve supplies the rhomboid major and minor muscles and are responsible for retraction of the scapula. The thoracodorsal nerve supplies the latissimus dorsi muscle, which adducts, medially rotates, and extends the arm.

Deltoid (anterior part) movement

Clavicular flexes and medially rotates arm

Pectoralis major medial attachment

Clavicular head: anterior surface of medial half of clavicle Sternocostal head: anterior surface of sternum, superior six costal cartilages, aponeurosis of external oblique muscle

A 25-year-old male bodybuilder complains of difficulty moving his right shoulder for the past 2 weeks. Upon physical examination, the muscles of the left upper back and shoulder were notably larger than the right side. There was a notable decrease of muscle power on his right sided upper back and shoulder muscles when he was asked to pull the shoulder blades toward the middle of his back against resistance. Nerve conduction examination confirmed neurapraxia of the nerves supplying the rhomboid major and minor muscles. In which of the following functions will the bodybuilder most likely also demonstrate weakness?? A. Abduction of the right arm above the horizontal level and protraction of the scapula B. Medial rotation and adduction of the right arm C. Extensions, adduction, and medial rotation of the right arm D. Elevation of the scapula and inferior rotation of the right shoulder E. Abduction of the right arm from 0 to 15 degrees

D. The rhomboid major and minor are supplied by the dorsal scapular nerve which also supplies the levator scapulae. The function of levator scapulae is elevation and inferior rotation of the scapulae. Abduction of the arm above 90 degrees and protraction of the scapula are possible due to the action of serratus anterior, which is supplied by the long thoracic nerve. Medial rotation and adduction of the arm is performed mainly by the pectoralis major and latissimus dorsi, which also extends the arm. These are supplied by the medial and lateral pectoral nerves and thoracodorsal, respectively. Abduction of the arm through 0 to 15 degrees is produced by supraspinatus, which is supplied by the suprascapular nerve

Which muscle abducts the arms from 15 to 90 degrees?

Deltoid

Deltoid Proximal Attachments Mnemonic

Deltoid CLASPs - CLavicle, Acromion, SPine of scapula

A 7-year-old boy was playing on the monkey bars when he lost his grip and fell. He lay on the ground crying that his shoulder hurt. His mother rushed to comfort him and observed swelling in the area of the right shoulder. She drove him to the emergency room where he was examined. Physical examination revealed swelling and tenderness in the shoulder region. Neurovascular assessment was unremarkable and breath sounds were normal. Radiographs showed a fracture of the acromion process. Which muscles are affected? A. Deltoid and Trapezius B. Rhomboid major and minor C. Teres major and Minor D. Levator scapula and Deltoid

Deltoid and Trapezius

Levator scapulae bloodsupply

Dorsal scapular artery

Rhomboid major & minor bloodsupply

Dorsal scapular artery

Rhomboid major & minor innervation

Dorsal scapular nerve (C4, C5)

Levator scapulae innervation

Dorsal scapular nerve (C5), and C3&C4 to upper part

Deltoid (posterior part) movement

Extends and laterally rotates arm

Muscles producing depression of the scapula (in order of importance)

Gravity; pectoralis major; latissimus dorsi; trapezius (inferior); serratus anterior; pectoralis minor

teres minor insertion

Inferior facet of greater tubercle of humerus

pectoralis major innervation

Lateral and medial pectoral nerves; clavicular head (C5, C6), sternocostal head (C7, C8, T1)

Pectoralis major lateral attachment

Lateral lip of intertubercular sulcus of humerus

Muscles producing downward rotation of the scapula (in order of importance)

Latissimus dorsi, gravity, levator scapulae, rhomboids, pectoralis minor, pectoralis major

Dorsal Scapular nerve goes to which muscles

Levator scapulae, rhomboids

teres major innervation

Lower subscapular nerve (C5, C6)

Supraspinatus Origin

Medial 2/3 of supraspinous fossa of scapula

rhomboid minor insertion

Medial border of scapula at spine of scapula

rhomboid major insertion

Medial border of scapula inferior to spine

teres major insertion

Medial lip of intertubercular groove of the anterior surface of the humerus

pectoralis minor innervation

Medial pectoral nerve (C8, T1)

infraspinatous insertion

Middle facet of greater tubercle of humerus

how do you test the accessory nerve

Most common cause - iatrogenic This can be done by asking the patient to shrug his/her shoulders. Other clinical features of accessory nerve damage include muscle wasting, partial paralysis of the sternocleidomastoid, and an asymmetrical neckline

What lies structure lies between the deltoid and pectoralis major and what vein runs through it?

Pectoral groove (deltopectoral triangle), cephalic vein

teres major origin

Posterior surface of inferior angle of scapula, lower lateral border

Serratus Anterior Innervation Mnemonic

SALT - Serratus Anterior = Long Thoracic

pectoralis minor main action

Stabilizes scapula by drawing inferiorly and anteriorly against thoracic wall

supraspinatus insertion

Superior facet of greater tubercle of humerus

infraspinatous innervation

Suprascapular nerve (C4, C5, C6)

Which muscle abducts the arm for the first 15 degrees?

Supraspinatus

A ballet dancer falls to the floor and hurts herself during a practice session before opening night. She sustains an injury to the thoracodorsal nerve that would probably affect the strength of which of the following movements A. Extension of the arm B. Adduction of the scapula C. Elevation of the scapula D. Abduction of the arm

The answer is extension of the arm. The thoracodorsal nerve innervates the latissimus dorsi, which adducts, extends, and medially rotates the arm. The arm is abducted by the supraspinatus and laterally rotated by the infraspinatus, teres minor, and deltoid (posterior part) muscles. The scapula is elevated by the trapezius and levator scapulae muscles and adducted by the rhomboid and trapezius muscles.

Following a radical mastectomy, a surgeon plans to conduct a breast reconstruction utilizing a latissimus dorsi muscle flap. What nerve will the surgeon need to keep intact during the surgical dissection of the chest wall to prevent atrophy of the muscle flap? A. Long thoracic B. Thoracodorsal C. Suprascapular D. Spinal accessory E. Dorsal scapular

The answer is thoracodorsal nerve. Successful transposition of muscle flaps in reconstructive surgery hinges largely on maintaining the neurovascular pedicles that supply the muscle. The latissimus dorsi muscle is innervated by the thoracodorsal (middle subscapular) nerve, a branch of the posterior cord of the brachial plexus. Lesion of this nerve during dissection of the chest wall will cause loss of the muscle flap.

Latissimus dorsi innervation

Thoracodorsal nerve (C6, C7, C8)

how do you test the rhomboids

To test the rhomboids, the individual places his or her hands posteriorly on the hips, and pushes the elbows posteriorly against resistance provided by the examiner. If the rhomboids are acting normally, they can be palpated along the medial borders of the scapulae

how do you test the serratus anterior

To test the serratus anterior - the hand of the outstretched limb is pushed against a wall. If the muscle is acting normally, several digitations of the muscle can be seen and palpated. If the muscle is paralyzed The arm cannot be abducted above the horizontal position because the serratus anterior is unable to rotate the glenoid cavity superiorly to allow complete abduction of the limb.

Trapezius bloodsupply

Transverse cervical artery

Accessorys go around your neck

Transverse cervical artery and accessory nerve for trapezius

Muscles producing elevation of the scapula (in order of importance)

Trapezius (superior), levator scapulae, rhomboids

Triangle of Auscultation significance

Used to listen to (auscultate) the lungs because the stethoscope can be placed close to the thoracic wall at this location Within this triangle, intercostal space 6 has no overlying muscles

Lumbar triangle significance

a hernia of the posterior abdominal wall may develop here

Deltoid (mid part) movement

acromial abducts arm

Teres major movement

adduct and medially rotate arm

subscapularis movement

adduct and medially rotate arm (backward rotation of palm), part of rotator cuff

Rhomboid major & minor movement

adduct, elevate, retract scap; rotate scap to depress glenoid cavity; stabilize scap to thoracic wall

Latissimus dorsi movement

adduct, medially rotate, extend humerus; raises body towards arms during climbing

Subclavius main action

anchors and depresses clavicle

serratus anterior insertion

anterior surface of medial border of scapula

Pectoralis minor is a landmark for the _____ artery

axillary

3 groups of lymph nodes receive lymph from breast tissue

axillary (75%), parasternal (20%), posterior intercostal (5%)

sixties teens love sex and pot

branches of axillary artery: superior thoracic artery, thoracoacromial trunk, lateral thoracic artery, subscapular artery, anterior circumflex humeral artery, posterior circumflex humeral artery

corpses are dead people

branches of thoracoacromial trunk from medial to lateral - clavicular, acromial, deltoid, pectoral

Areola

circular pigmented skin surrounding the nipple; contains modified sebaceous and sweat glands

teres major blood supply

circumflex scapular artery

teres minor blood supply

circumflex scapular artery

Deltoid all movements

clavicular (ant) flexes and medially rotates arm'; acromial (mid) abducts arm; spinal (post) extends and laterally rotates arm *abducts (acromial part) beyond 15 degrees

Subclavius blood supply

clavicular branch of thoracoacromial trunk

subclavius blood supply

clavicular branch of thoracoacromial trunk

pectoralis minor lateral attachment

coracoid process of scapula

what causes winged scapula

damage to the long thoracic nerve which lays above and innervates the serratus anterior

deltoid insertion

deltoid tuberosity of humerus

subclavius movement

depress lateral part of the clavicle

pectoralis minor movement

depress scapula, elevate ribs, protract scapula

Trapezius (inferior part)

depresses scapula

Following a knife wound to the neck, you notice that the medial border of a patient's left scapula is located further from the midline than that of his right scapula. The nerve most likely injured by the wound is which of the following? A. Long thoracic B. Thoracodorsal C. Suprascapular D. Spinal accessory E. Dorsal scapular

dorsal scapular

Nipple

each lobule opens into a lactiferous duct and the duct expands to a sinus and then opens into the nipple

Trapezius (superior part) movement

elevates scapula

Levator scapulae movement

elevates scapula and tilts glenoid cavity inferiorly by rotation

Trapezius all movements

elevates, retracts, depresses (adducts, rotates) scapula

Pectoralis major movement

flex, adduct, and medially rotate arm, draws scapula anterio-inferiorly

supraspinatus movement

initiates/helps deltoid to abduct arm (part of rotator cuff)

Subclavius lateral attachment (insertion)

interior surface of middle 1/3rd of clavicle

latissimus dorsi insertion

intertubercular groove (sulcus) of humerus

greatest clinical importance of breast lymphatics is

its role in the metastasis of breast cancer cells

Subclavius medial attachment (origin)

junction of the 1st rib and its costal cartilage

Deltoid origin

lateral 1/3 of clavicle, acromion, spine of scapula

Trapezius Insertion

lateral 1/3 of clavicle, acromion, spine of scapula

The breast is innervated by the

lateral and anterior branches of the 4-6th intercostal nerves

pectoralis major innervation

lateral and medial pectoral nerves

clavipectoral fascia innervation

lateral pectoral nerve

serratus anterior blood supply

lateral thoracic artery

the thoracodorsal nerve goes to which muscle

latissimus dorsi

Lumbar Triangle boundaries

latissimus dorsi (medially), external oblique (laterally), iliac crest (inferiorly), internal abdominal oblique (floor)

subscapularis insertion

less tubercle of humerus

serratus anterior innervation

long thoracic nerve

Lt. serratus anterior

long thoracic nerve, lateral thoracic artery (run parallel to each other)

Trapezius Origin

medial 1/3 of superior nuchal line, external occipital protuberance, nuchal ligament, spinous processes of C7-T12

infraspinatous origin

medial 2/3s of the infraspinous fossa of the scapula

levator scapulae insertion

medial border of scapula superior to spine

pectoralis minor innervation

medial pectoral nerve

The breast is supplied

medially by the internal thoracic artery (branch of the subclavian) laterally by the lateral thoracic and thoracoacromial branches (originate from the axillary artery), the lateral mammary branches, and the mammary branch lateral thoracic and internal thoracic vein

The breast is a..

modified sweat gland consisting of secretory epithelial tissue within the adipose tissue

subclavius innervation

nerve to subclavius

pectoralis major blood supply

pectoral branch of thoracoacromial trunk

pectoralis minor blood supply

pectoral branch of thoracoacromial trunk

the pectoral nerves go to which muscles

pectoralis major and minor (medial pectoral)

Clavipectoral fascia encloses the

pectoralis minor & subclavius

deltoid blood supply

posterior circumflex humeral artery

glenohumeral joint abduction

prime mover: deltoid synergist: supraspinatus

glenohumeral joint extension

prime mover: deltoid (spinal part) synergist: teres major, latissimus dorsi, long head of triceps brachii

glenohumeral joint lateral rotation

prime mover: infraspinatus synergists: teres minor, deltoid (spinal part)

glenohumeral joint flexion

prime mover: pectoralis major (clavicular head), deltoid (clavicular and acromial head) synergist: coracobrachialis

glenohumeral joint adduction

prime mover: pectoralis major, latissimus dorsi synergists: teres major, long head of triceps brachii

glenohumeral joint medial rotation

prime mover: subscapularis synergists: pectoralis major, deltoid (clavicular part), latissimus dorsi, teres minor

serratus anterior movement

protracts scapula and holds against thoracic wall, rotates scapula

Trapezius (mid part) movement

retracts scapula

The breast lies superficial to the ______

retromammary space, then pectoral fascia, then pectoralis major, then pectoralis minor

infraspinatuous movement

rotates arm laterally (holds humeral head in glenoid cavity), part of rotator cuff

teres minor movement

rotates arm laterally (holds humeral head in glenoid cavity), part of rotator cuff

the long thoracic nerve goes to which muscle

serratus anterior

Muscles producing protraction (opposite of retraction) of the scapula (in order of importance)

serratus anterior, pectoralis major, pectoralis minor

Layers of the back

skin, superficial fascia, deep fascia, muscular fascia, neurovascular bundle

Trapezius innervation

spinal accessory nerve (motor), and ventral rami C3, C4 (proprioception and pain)

rhomboid minor origin

spinous processes of C7-T1 and inferior end of the nuchal ligament

Rhomboid major origin

spinous processes of T2-T5

subclavius innervation

subclavian nerve (C5, C6)

subscapularis blood supply

subscapular artery

Subscapularis origin

subscapular fossa of scapula (anterior side)

the __________ quadrant of the breast extends along the inferior edge of the pectoralis major as the ______ tail

superolateral; axillary

infrapinatous blood supply

suprascapular artery

supraspinatus blood supply

suprascapular artery

supraspinatous innervation

suprascapular nerve (C4, C5, C6)

Rotator Cuff Mnemonic

the SITS muscles - first 3 in the greater tubercle (supraspinatous, infraspinatous, teres minor) - last 1 in the lesser tubercle (subscapularis)

how do you test the latissimus dorsi

the arm is abducted 90 and then adducted against resistance provided by the examiner. If the muscle is normal, the anterior border of the muscle can be seen and easily palpated in the posterior axillary fold It is also useful in restoring the upper limb from abduction superior to the shoulder; hence the latissimus dorsi is important in climbing. In conjunction with the pectoralis major, the latissimus dorsi raises the trunk to the arm, which occurs when performing chin-ups (hoisting oneself so the chin touches an overhead bar) or climbing a tree. These movements are also used when chopping wood, paddling a canoe, and swimming (particularly during the crawl stroke).

what does the dorsal scapular nerve supply

the rhomboids and the levator scapulae

Which muscle abducts the arm above 90 degrees?

this requires rotation of the scapula (including superior rotation of the glenoid fossa) - serratus anterior

clavipectoral fascia artery

thoracoacromial artery

Latissimus dorsi blood supply

thoracodorsal artery

levator scapulae origin

transverse processes of vertebrae C1-C4

the spinal accessory nerve goes to which muscle

trapezius

Triangle of Auscultation boundaries

trapezius (medially), latissimus dorsi (inferiorly), rhomboid major (superiorly), posterior thoracic wall (floor)

Muscles producing retraction of the scapula (in order of importance)

trapezius (middle), trapezius (inferior), serratus anterior

Muscles producing upward rotation of the scapula (in order of importance)

trapezius (superior), serratus anterior, trapezius (inferior)

types of collagen

type 1 - bONE type 2 - carTWOlage type 3 - reTRIcular type 4 - on the floor (rhyme bc 4 is on basement membrane which is like the floor)

Teres minor origin

upper 2/3 of lateral border of scapula (posterior surface)

subscapularis innervation

upper and lower subscapular nerves (C5, C6, C7)

Latissimus dorsi origin

vertebral spines from T7 to the sacrum, posterior third of the iliac crest, lower 3 or 4 ribs, sometimes from the inferior angle of the scapula, thoracolumbar fascia