Ch 24 Muscles of the Superficial Back, Shoulder, and Axilla
subscapularis teres major latissimus dorsi
Anterior view of shoulder (after removal of pectoralis major m.):
supraspinatus subscapularis
Anterior view of shoulder:
deltoid pectoralis major
Anterior view:
pectoralis minor serratus anterior
Anterior view:
articular capsule
At insertions, rotator cuff muscle tendons fuse with fibrous .... of glenohumeral joint
holding head of humerus within glenoid fossa of scapula
In addition to the individual actions, all four rotator cuff muscles also have common action of:
anterior axillary fold
In the anterior wall of the axilla is the pectoralis major muscle, the inferior free edge of this muscle forms ...
posterior axillary fold
In the posterior wall of the axilla is the latissimus and teres major muscles, the inferior free edge of these muscles forms ...
latissimus dorsi pectoralis major anterior axillary fold posterior axillary fold
Lateral view:
line of insertion for serratus anterior serratus anterior
Lateral view:
pectoralis minor
Lateral view:
serratus anterior
Lateral view:
subscapularis (deep side of scapula)
Lateral view:
supraspinatus infraspinatus teres minor
Posterior view of shoulder:
supraspinatus m. infraspinatus m. deltoid m. teres minor m. teres major m.
Posterior view of shoulder:
trapezius
Posterior view:
trapezius latissimus dorsi
Posterior view:
trapezius latissimus dorsi aponeurosis
Posterior view:
superior posterior anterior
Rotator Cuff Muscles cross ... , ... , and ... to shoulder joint
scapula greater or lesser tubercles of humerus
Rotator Cuff Muscles have origins from ... and insert onto ...
ligamentum nuchae trapezius
Superficial back muscles:
trapezius
Superficial back muscles:
latissimus dorsi
Superficial muscles of the back:
latissimus dorsi aponeurosis
Superficial muscles of the back:
levator scapulae spine of scapula
Superficial muscles of the back:
rhomboids spine of scapula
Superficial muscles of the back:
upper fibers of trapezius lower fibers of trapezius lower fibers of serratus anterior
Superior Rotation of Scapula:
armpit
The axilla has a pyramid-shaped space - the floor of the pyramid is the ...
upper limb body trunk
The axilla is the junction between the ... and ...
nerves artery vein
The axilla provides passage for major ..., ..., and ... entering upper limb
trapezius (upper fibers) trapezius (lower fibers) serratus anterior (lower fibers)
The muscles that produce superior rotation of the scapula:
pectoralis major teres major latissimus dorsi subscapularis
The powerful actions of adduction and medial rotation of the arm are used for carrying heavy objects against chest and these actions are produced by four muscles:
axial skeleton to shoulder axial skeleton to humerus pectoral girdle to humerus
There are three group muscles indicating where the superficial back muscles and shoulder muscles run:
latissimus dorsi teres major axilla serratus anterior pectoralis major
View of axilla from above:
serratus anterior muscle
a broad, flat muscle that wraps around lateral and posterior sides of rib cage
superior rotation of scapula
action of both trapezius upper and lower muscle fibers:
flexion of arm at shoulder
action of deltoid anterior muscle fibers: (muscle passes anterior to shoulder joint)
abduction of arm at shoulder
action of deltoid middle muscle fibers: (muscle passes super to (over) shoulder joint)
extension of arm at shoulder
action of deltoid posterior muscle fibers: (muscle passes posterior to shoulder joint)
lateral rotation of arm at shoulder joint
action of infraspinatus muscle:
elevates scapula
action of levator scapulae muscle:
inferior rotation of scapula
action of pectoralis minor muscle:
retracts (adducts) scapula
action of rhomboid muscles:
medial rotation of arm at shoulder joint
action of subscapularis muscle:
abduction of humerus at shoulder
action of supraspinatus muscle:
lateral rotation of arm at shoulder joint
action of teres minor muscle:
depression of scapula
action of trapezius lower muscle fibers only:
retraction of scapula
action of trapezius middle muscle fibers only:
elevation of scapula
action of trapezius upper muscle fibers only:
anterior fibers: flexion of arm at shoulder posterior fibers: extension of arm at shoulder middle fibers: abduction of arm at shoulder
actions of deltoid muscle:
extends, adducts, and medially rotates humerus at shoulder
actions of latissimus dorsi muscle (3):
adduction and medial rotation of arm at shoulder extension of flexed arm
actions of pectoralis major muscle:
superior rotation of scapula
actions of serratus anterior muscle (anterior 1/2 only):
-protraction of scapula (during pushing, punching actions) -holds scapula against posterior body wall
actions of serratus anterior muscle (entire muscle):
extends, adducts, and medially rotates arm at shoulder
actions of teres major muscle:
upper fibers only: elevation of scapula middle fibers: retraction of scapula lower fibers only: depression of scapula upper + lower fibers: superior rotation of scapula
actions of trapezius muscle -upper fibers only -middle fibers only -lower fibers only -upper fibers + lower fibers
deltoid
anterior view of shoulder:
teres major
anterior view of shoulder:
anterior and posterior axillary folds
axillary fascia is deep investing fascia that spans between ... and ... (forms floor of armpit)
pectoralis major latissimus dorsi teres major
bicipital groove of humerus is the site if insertion for 3 muscles:
lateral
deltoid muscle is a triangle-shaped muscle that covers the ... shoulder
anterior fibers posterior fibers middle fibers
deltoid muscle is functionally divided into three parts for its actions:
rotator cuff
four muscle tendons + thickened articular capsule
trapezius latissimus dorsi levator scapulae rhomboid
four superficial back muscles:
glenoid fossa (supports shoulder joint)
infraspinatus muscle also holds the head of humerus in ...
shoulder joint
infraspinatus muscle runs laterally, passing posterior to...
deltoid tuberosity of humerus
insertion of deltoid muscle:
greater tubercle of humerus
insertion of infraspinatus muscle:
bicipital groove of humerus (anterior side)
insertion of latissimus dorsi muscle:
medial border of scapula, above base of scapular spine
insertion of levator scapulae muscle:
bicipital groove of humerus
insertion of pectoralis major muscle:
coracoid process of scapula
insertion of pectoralis minor muscle:
medial border of scapula, at and below base of scapular spine
insertion of rhomboid muscles:
-upper 1/2 of muscle: to medial border of scapula -lower 1/2 of muscle: to inferior angle of scapula
insertion of serratus anterior muscle (upper and lower 1/2's):
lesser tubercle of humerus
insertion of subscapularis muscle:
greater tubercle of humerus
insertion of supraspinatus muscle:
bicipital groove of humerus
insertion of teres major muscle:
greater tubercle of humerus
insertion of teres minor muscle:
-upper fibers: lateral clavicle -middle fibers: acromion -lower fibers: spine of scapula
insertion of trapezius muscle -upper fibers -middle fibers -lower fibers
medial rotation of humerus
latissimus dorsi muscle passes to bicipital groove on anterior side of humerus - pulls anterior side of humerus toward mid-line: ...
adducts arm
latissimus dorsi muscle runs from medial to lateral - ...
arm extension
latissimus dorsi muscle runs from posterior back to anterior humerus - can produce full (maximum) range of ...
trapezius
levator scapulae muscle is located deep to upper part of ... muscle
rotator cuff muscles
most important muscles for support of shoulder
subscapularis muscle
only muscle that inserts onto lesser tubercle
lateral clavicle, acromion, and spine of scapula
origin of deltoid muscle:
infraspinous fossa of scapula
origin of infraspinatus muscle:
spinous processes of lower thoracic (T7-T12) vertebrae, lumbar (L1-L5) vertebrae, posterior sacrum, and posterior iliac crest
origin of latissimus dorsi muscle:
cervical vertebrae
origin of levator scapulae muscle:
clavicle, sternum, upper ribs
origin of pectoralis major muscle:
upper, anterior rib cage
origin of pectoralis minor muscle:
spinous processes of upper thoracic vertebrae
origin of rhomboid muscles:
lateral sides of ribs 1-8
origin of serratus anterior muscle:
subscapular fossa of scapula
origin of subscapularis muscle:
supraspinous fossa of scapula
origin of supraspinatus muscle:
lateral border of scapula
origin of teres major muscle:
lateral border of scapule
origin of teres minor muscle:
posterior skull and spinous processes of cervical (C1-C7) and thoracic (T1-T12) vertebrae
origin of trapezius muscle:
winged scapula
paralysis of serratus anterior muscle produces ... - the medial border of scapula pulls away from body during pushing motion
full extension
pectoralis major muscle does not produce ... of arm at shoulder
deltoid
posterior view of shoulder:
teres major
posterior view of shoulder:
trapezius deltoid teres major
posterior view:
middle trapzeius
rhomboid muscles are located deep to ... muscle
rhomboid major rhomboid minor
rhomboid muscles are subdivided into ... and ... muscles
trapezius
serratus anterior muscle acts in combination with upper and lower ... muscle
humerus
serratus anterior muscle holds scapula against posterior body wall - anchors the scapula when rotator cuff muscles contract on the ...
scapula
serratus anterior muscle passes deep to entire ... before inserting
pectoralis minor muscle
small, thin muscle located deep to the pectoralis major muscle
extends arm (moves it posteriorly)
starting from the flexed position, pectoralis major only ... back to the anatomical position
head of humerus
subscapularis muscle also holds .. in glenoid fossa (supports shoulder joint)
inferior 1/2 of serratus anterior muscle
superior rotation of scapula by the upper and lower muscle fibers of trapezius also involves the ... muscle
glenoid fossa (supports shoulder joint)
supraspinatus muscle also holds the head of humerus in ...
supraspinatus middle fibers of deltoid
supraspinatus muscle passes over (superior to) shoulder joint - only ... and ... product abduction of the arm at the shoulder joint
acromion
supraspinatus muscle runs laterally, passing deep to ...
latissimus dorsi
teres major muscle has the same actions as ... muscle
adduction medial rotation extension
teres major muscle is a powerful muscle for ... and ... , but weak muscle for ...
head of humerus
teres minor muscle also holds ... in glenoid fossa (supports shoulder joint)
shoulder joint
teres minor muscle runs laterally, passing posterior to ...
axilla
the "armpit area"
pectoralis major muscle -inferior free edge of muscle forms anterior axillary fold
the anterior wall boundary of the axilla consists of:
clavicle pectoralis minor muscle (at its insertion onto coracoid process of scapula)
the apex of pyramid projects inward, deep to ... and ...
axillary fascia
the base boundary of the axilla consists of:
anterior
the bicipital groove is located on the ... side of humerus
weak
the glenohumeral (shoulder) joint has ... ligaments that allows a large range of motion
latissimus dorsi
the insertion of teres major muscle with bicipital groove is fused with the insertion of ... muscle
aponeurosis
the latissimus dorsi muscle uses broad ... for the origin from thoracic and lumber vertebrae
serratus anterior muscle (passes deep to scapula to insert onto medial border)
the medial wall boundary of the axilla consists of:
middle muscle fibers of deltoid
the muscle fibers that are the most powerful part of deltoid
"serrated"
the origin of serratus anterior muscle is of individual muscle slips off each rib give ... appearance to muscle
latissimus dorsi and teres major muscles -inferior free edge of muscle forms posterior axillary fold
the posterior wall boundary of the axilla consists of:
pectoral girdle (clavicle, scapula) arm at shoulder joint
the superficial back muscles and shoulder muscles are all involved in movements of the ... or the ...
deltoid teres major
there are 2 posterior shoulder muscles:
trapezius levator scapulae rhomboid serratus anterior pectoralis minor muscles
there are five muscles running from axial skeleton into pectoral girdle:
anterior wall posterior wall medial wall base
there are four boundaries of the axilla:
supraspinatus muscle infraspinatus muscle teres minor muscle subscapularis muscle
there are four rotator cuff muscles:
supraspinatus infraspinatus teres minor subscapularis deltoid teres major muscles
there are six muscles running from pectoral girdle to humerus:
pectoralis major muscle pectoralis minor muscle serratus anterior muscle
there are three anterior and lateral shoulder muscles:
latissimus dorsi pectoralis major muscles
there are two muscles running from axial skeleton to humerus:
upper fibers middle fibers lower fibers
three parts of trapezius muscle can be used independently for movements:
latissimus dorsi
trapezius is superficial of ... muscle
back-forth swinging
weaker anterior and posterior muscle fibers of deltoid produce ... of upper limb during walking
