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