S1| HUMAN ANATOMY

CE
DRA. MARIA LUISA PARLADE | 10 04-05 21
BATCH
2025

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FOUR SEGMENTS OF THE UPPER LIMB
• SHOULDER- pectoral, scapular, and deltoid
regions; pectoral girdle (formed by scapulae
- Flat
-Articulates with acromion of scapula at
acromioclavicular joint.
- Medial 2/3 of the shaft are convex

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and clavicles)
• ARM- longest segment; between shoulder anteriorly while lateral 1/3 flattened and concave
and elbow; humerus anteriorly
• FOREARM- second longest; between elbow B. Superior surface
and wrist; radius and ulna - Smooth
• HAND- wrist, palm, dorsum of hand, and - Lying deep to the skin and platysma
digits muscle (subcutaneous tissue)
C. Inferior surface
- Rough due to the ligaments binding to it
PECTORAL GIRDLE D. Conoid Tubercle
- Bony ring composed of the Clavicle and -Acromial end of clavicle
Scapula -Attaches to the conoid ligaments (medial
- Movement involves: part of coracoclavicular ligament)
• STERNOCLAVICULAR E. Trapezoid line
• ACROMIOCLAVICULAR - Near acromial end
• GLENOHUMERAL JOINTS -Attaches to the trapezoid ligament (lateral
BONES OF THE PECTORAL GIRDLE part of coracoclavicular ligament)
1. CLAVICLE F. SUBCLAVIAN
-Median 1/3 of the shaft
- AKA the collar bone
-Attachment of the subclavius muscle
- ONLY connect of the upper limb to the
G. Impression for costoclavicular ligament
trunk
-More medially found than subclavian
- Long bones and S-shaped
groove (Rough, depressed, oval area)
- No marrow cavity; consist of spongy,
- Attachment of the Costoclavicular
trabecular bone-prone to fracture(Most
ligament- ligament binding the 1st rib to the clavicle
commons site: Junction of the medial 2/3
and lateral 1/3 of the clavicle)
- Fxn:
- Serves as a moveable rigid support, w/c
the scapula and free limb are suspended,
keeping them away from the trunk/body
- Allows maximal movement of limb
- Forms the cervico-axillary canal which
becomes passage way between the neck
and arm for neurovascular bundles
- Transmit shock from upper limb to the

axial skeleton
- Parts:
A. Shaft- Ha double curve horizontally
- Sternal end
- Convex anteriorly
- Enlarge and triangular
- Articulates with manubrium of the
sternoclavicular joint
- Acromial end
-Concave anteriorly
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REYES, BERDIN, MALATE
S1| HUMAN ANATOMY
CE
DRA. MARIA LUISA PARLADE | 10 04-05 21
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2025

|\ 2. SCAPULA
-Prominence indicating medial point of
attachment of deltoid
J. Glenoid cavity
- Lateral surface of the scapula

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-Receives and articulates with head of
humerus at glenohumeral joint.
-Shallow, concave, oval fossa
-Primary feature of the head of scapula
-Oriented: Superiorly, Anteriorly, Laterally
-Contains Superior and Inferior tubercle for
the attachment of long head of biceps brachii and
triceps brachii
K. Coracoid process
- Beak-like
- Superior to the glenoid fossa
- Triangular flat bone on the posterolateral
- Provides inferior attachment for
aspectof the thorax
supporting the coracoclavicular ligament
- Overflies 2nd-7th ribs
- Provides attachment for muscles such as
- Parts:
Pectoralis minor and short heads of the biceps
A. Posterior Surface
brachii
-Convex
L. Head
B. Spine
-Bears the glenoid fossa
- Thick projecting ridge of the bone
M. Neck
- Unevenly divides the posterior surface of
-Shallow constriction between the head and
the scapula
body
- Serve as levers for attached muscles
- Levers- A rigid rod (usually a length of
BOARDERS OF THE SCAPULA
bone) that turns about a pivot (usually a joint); can
• Medial border
be used so that a small force can move a much
- Thin and runs parallel and lateral to the
bigger force.
spinous process of thoracis vertebra
-Align at the 73 spinous process.
- AKA the vertebral border
C. Supraspinous fossa
• Lateral Border
-Smaller division of the posterior surface
- Runs supero-laterally toward apex of axilla
-Provide attachments for SUPRASPINATUS
- AKA the axillary border
muscle
- Made of thick bar bone that prevents
D. Infraspinous fossa
buckling of this part of the scapula
- Larger division of the posterior surface
- Provide attachment for INFRASPINATUS • Superior border
muscle - Marked near junction of the medial 2/3 and
E. Costal surface lateral 1/3 by the suprascapular notch –
-Concave passageway of suprascapular nerve covered
F. Subscapular fossa by transverse scapular ligament
- Formed from the costal surface - Thinnest and shortest among borders
- Provide attachments for SUBSCAPULARIS
muscle. ANGLES OF SCAPULA
G. Body of the scapula • SCAPULA – lies at level T2 vertebra
- Translucent, triangular, and thin, except • Lateral- thickest part, bears head of
for borders and the lateral edge being thicker scapula
-Superior and inferior to the scapular spine • Inferior- T7 vertebra, near 7th rib and 7th
H. Acromion/ Acromion process intercostal space; visible and easily felt
- Lateral continuation of the spine
- Forms the highest and Subcutaneous point
of the shoulder
- Articulates with acromial and end of
clavicle
- Serves as lever for attached muscles.
I. Deltoid Tubercle of scapular spine
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S1| HUMAN ANATOMY
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DRA. MARIA LUISA PARLADE | 10 04-05 21
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2025

|\ •
-
Shaft
Has the following features
➢ Deltoid Tuberosity- For attachment
of deltoid muscles

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- Found Laterally
➢ Radial groove/ Spiral groove
-Found laterally
-For passage of radial nerve and
deep artery
-Common compression site of
3. HUMERUS
radial nerve
• Epicondyles
-Forms the long bone of the arm
- Supraepicondylar ridge
-Largest bone in the upper limb
- Found medially and laterally
- Inferior end of the humerus widens as the
PARTS:
ridges
• HEAD ➢ Medial Epicondyle- For muscle
- Articulates with the scapula at the attachment; common attachment
glenohumeral joint, and with radius and of muscles of the anterior
ulna at the glenohumeral joint, and with compartment of the forearm
radius and ulna at the elbow joint ( superficial layer)
- Attaches to the glenoid fossa of scapula ➢ Lateral Epicondyle- For muscle
- Orientation: Medially, Posteriorly, and attachment ; common attachment
Superiorly of most muscles in the posterior
compartment of the forearm
• Condyle
- Distal end of the humerus
- Has two articular surfaces:
❖ Capitulum- Little head; spherical in
shape
-For articulation with the head of
radius
❖ Trochlea- “pulley”, “Moon-shaped”
-Articulation with proximal end of
ulna.
- Note: Orientation of Humeral head is
• Fossae
aligned with the orientation of glenoid
- Hallows that occur back to the distal end of
fossa- Superiorly, Anteriorly, Laterally
humerus
- Glenoid fossa= superiorly, anteriorly,
❖ Coronoid fossa
laterally
-Anterior-medial
- Huhuhu MPS= Humerus- medially,
-Receives coronoid process for ulna
posteriorly, superior
during full flexion of elbow
• Anatomical neck
❖ Olecranon fossa
- Indicates line of attachment of
-Posterior
glenohumeral joint capsule
-Accommodates olecranon of ulna
• Surgical neck during full flexion of elbow
- Common sight of fracture ❖ Radial fossa-
- May damage Axillary nerve when fracture -Antero-lateral
- Narrow part distal to head and tubercles -Accommodates edge of radius
• Greater Tubercle head
- Found at the lateral margin
FRACTURES OF HUMERUS
• Lesser Tubercle
- Occur during anterior and posterior dislocations of
- Projects anteriorly from the bone
the shoulder joint.
• Bacipital groove/ Intertubercular sulcus - Glenoid labrum produces the fracture
- Separates tubercles - Labrum can become jammed in the defect making
- Provides passage for tendons of biceps- reduction of the shoulder joint difficult
covered by transverse
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S1| HUMAN ANATOMY
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DRA. MARIA LUISA PARLADE | 10 04-05 21
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2025

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GREATER TUBEROSITY FRACTURE
- Direct trauma displaced by the glenoid labrum
during dislocation of shoulder
- avulsed by violent contractions of the
supraspinatus muscles
LESSER TUBEROSITY FRACTURE
- Accompanies posterior dislocation of the joint
- Bone fragments receives insertion of the
subscapularis tendon.

SURGICAL NECK FRACTURES

- Immediately distal to the lesser tuberosity
- By direct blow on the lateral aspect of the shoulder
- Indirect manner by falling out on the outstretched
hand.

JOINTS OF THE UPPER LIMB

HUMERAL SHAFT FRACTURES
-Common

• Defects impair movements of the pectoral

girdle
• Mobility of the scapula – essential for free
movement of the upper limb
• Clavicle forms strut with hold scapula away
from the thorax for independent movement

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REYES, BERDIN, MALATE
S1| HUMAN ANATOMY
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DRA. MARIA LUISA PARLADE | 10 04-05 21
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2025

|\• 15-20° movement at AC – positioning the

glenoid cavity and necessary for arm
movement
- A concentric rim of the fibrocartilage
widens and deepens the shallow
concavity of the bony glenoid
•

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Initial 30° abduction – may occur without - Providing the joint with inherent
scapular movement in overall movement of stability and restricting anterior and
elevating the arm full posterior excursions of the humerus
▪ Occurs in 2:1 ratio
▪ Scapulohumeral rhythm Capsule of the Glenohumeral
Important Movement of Pectoral Joint
Girdle • Fibrous layer that surrounds the
glenohumeral joint
• Elevation and depression • Medially attached to the margin of the
• Protraction (lateral or forward movement of glenoid cavity
scapula) • Laterally attached to the anatomic neck of
• Retraction (medial or backward movement the humerus
of the scapula) • Encloses the proximal attachment of the
• Rotation of the scapula long head of the biceps brachii to the
supraglenoid tubercle of scapula within the
joint
• Fibrous capsule envelops the joint,
• Extending from the base of the coracoid
through the supraglenoid region cranially
• Anatomic neck of the humerus laterally
• Into the labrum posteriorly and inferiorly
• With the arm in neutral position, the lower
portion of the capsule is lax and redundant,
and forms the axillary recess of the joint
• Capsule of the glenohumeral joint
- Is invested by the synovial membrane
• Made up of the relatively small and flat on its deep surface and over-lies some
glenoid fossa and the large and round intracapsular soft-tissue structures,
articular surface of the humeral head including the long head of the biceps
• The glenoid cavity covers only the small tendon.
portion (about one-fourth) of the humeral
2 Apertures
head
• Incongruity along with the relative laxity of 1. Opening between the tubercles of humerus
the joint capsule provides wide mobility but for passage of tendon of long head of the
makes the joint inherently unstable and biceps brachii
prone to subluxation and dislocation 2. Anterior opening inferior to the coracoid
• Articular surfaces of the humeral head and process – allows communication between
the glenoid fossa are covered by the layer of the subcapularis recess and synovial cavity
the hyaline cartilage, which is thicker in its of the joint
center in the humerus and thinner at its
outer edges in the glenoid SUBSCAPULARIS RECESS
• The articulat cartilage reaches the anatomic 1. Superior Subscapularis Recess
neck, the site of attachment of the joint - Communicates with the joint through
capsule an opening in the fibrous capsule
• Labrum – attached at its base to the located between the superior and
periphery of the glenoid middle glenohumeral ligaments

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REYES, BERDIN, MALATE
S1| HUMAN ANATOMY
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DRA. MARIA LUISA PARLADE | 10 04-05 21
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2025

|\ - Small saddle-shaped recess of the

glenohumeral joint that overlies the
subscapularis tendon
• Forms a tubular sheath for the long head of
biceps brachii

LIGAMENTS OF THE

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- Located in close relationship with the
root of the coracoid and plays a role in
GLENOHUMERAL JOINT
protecting the subscapularis tendon
during gliding over the scapular neck
2. Inferior Subscapularis Recess
- Projects between the middle and
inferior glenohumeral ligaments
- Located deep to the subscapularis
muscle due to its more inferior position

Anterior glenohumeral joint cavity has

three main extensions:
- Biceps tendon sheath anteriorly
- Subscapularis recess medially
- Axillary pouch inferiorly

CORACOHUMERAL LIGAMENT
- Strong board band that passes from the
base of the coracoid process to the
anterior aspect of greater tubercle

TRANSVERSE HUMERAL LIGAMENT

- a brand fibrous band that runs obliquely
from greater to the lesser trochanter
- bridges over the intertubercular groove
- converts the groove into a canal
- holds synovial sheath and tendon of
biceps brachii

GLENOHUMERAL LIGAMENT
- three fibrous bands that reinforce the
anterior part of the joint capsule
- radiate laterally and inferiorly from the
glenoid labrum at supraglenoid tubercle
of the scapula
- blend distally with the fibrous layer of
the capsule as attaches to the anatomic
neck of humerus
- extend from the anterior margin of the
glenoid cavity to the lesser tuberosity
and act as check to external rotation
and anterior translation of the humeral
SYNOVIAL MEMBRANE head

• Lines the internal surface of the capsule CORACOHUMERAL LIGAMENT

• Reflects onto the glenoid labrum and
humerus - is a strong band of fibrous tissue arising
from the coracoid and inserting onto
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REYES, BERDIN, MALATE
S1| HUMAN ANATOMY
CE
DRA. MARIA LUISA PARLADE | 10 04-05 21
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2025

|\ the greater and lesser tuberosities to

reinforce the capsule when it passes
over the intra-articular portion of the ▪
head of the humerus against the
glenoid fossa
Adduction: 45 deg across the front the

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biceps tendon chest
▪ Lateral Rotation: 40-45 deg
▪ Medial Rotation: 55 deg; subspularis, lat
dorsi; teres major; ant fibers of deltoid
➢ For every 15 deg of elevation
glenohumeral – 10 deg scapular
movement – 5 deg

STERNOCLAVICULAR JOINT
Articulation: between sternal end of the claviclr
manubrium sterni

CORACOACROMIAL ARCH
- Extrinsic protective structure formed by
smooth inferior aspect of acromion and
the coracoid process of the scapula –
coracoacromial ligament connecting it
- Forms a protective arch that overlies
the humeral head
- Prevents superior displacement from
the glenoid cavity
• Saddle type of synovial joint
- Very strong that forceful superior thrust
• Divided into two compartment by articular
will fracture it
disk
- Supraspinatus muscle passes under arch
• Anterior and Posterior SC ligament
- Subacromial bursa lies between the
arch and supraspinatus tendon and • Thickenings of Fibrous layer of the Joint
tubercle capsule
• Interclavicular ligaments
Movements of the Shoulder
Joint
• Wide range of the movement-stability of
joint is scarified
• Strength of the joint depends on the tone of
the rotator cuff muscles
• Abducted: lower surface of the head of the
humerus is supported by the long head of
triceps
• Inferior part of the capsule is the weakest
area
▪ Flexion: 90 deg ant fiber od deltoid,
pectoralis major, biceps,
coracobrachialis Sternoclavicular Joint
▪ Extension: 45 deg; post deltoid; lat dorsi
▪ Articular disc
▪ Abduction: between scapula and
▪ Great strength of the SC
thoracic wall supraspinatus muscle
▪ Shock absorber
initiates the movement and holds the
• Dislocation of the clavicle is rare

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REYES, BERDIN, MALATE
S1| HUMAN ANATOMY
CE
DRA. MARIA LUISA PARLADE | 10 04-05 21
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2025

|\ •
•
Fracture is common
Only articulation between upper limb and
axial skeleton
• Supplied by internal thoracic and
suprascapular arteries

Nerve Supply of SC Joint

•

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Readily palpated-sternal end of clavicle lies
superior to manubrium of the sternum • Supplied by branches of medial SC nerve
and Subclavius nerve
Articulation of SC Joint

• Sternal end of the clavicle articulates with ACROMIOCLAVICULAR JOINT

manubrium and 1st costal cartilage Articulation: acromion of the scapula and lateral
• Articular surfaces – covered with end of clavicle
fibrocartilage

Joint Capsule of SC Joint

• Surround the SC joint, including epiphysis at

the sternal end of the clavicle
• Attached to margin of the articular surfaces,
including the periphery of the articular disc
• Synovial membrane lines internal surface of
fibrous membrane of the joint capsule,
extending the edge of the articular surfaces

Ligaments of the SC Joint

• Strength of the SC depends on its ligaments

and articular disc
• Anterior and Posterior SC ligament –
reinforce joint capsule anteriorly and
posteriorly
• Interclavicular ligaments – strengthens
capsule superiorly
▪ Extends from sternal end of one clavicle
to the other
▪ In between, attached to superior
boarder of the manubrium
• Costoclavicular ligament – anchors the
inferior surface of sternal end of the clavicle
to 1st rib and its costal cartilage
▪ Limits elevation of pectoral girdle

Movements of SC Joint

▪ Full elevation (clavicle raised approx. 60°) Acromioclavicular Joint

▪ Achieved via Flexion – accompanied
by rotation of the clavicle around • Plane type of synovial joint
longitudinal axis • Located 2-3 cm from the point of the
• Can be moved anteriorly or posteriorly (25- shoulder formed by the lateral part of the
30°) acromion
▪ Not typical movement except
Articulation of AC Joints
calisthenics (systematic body
exercise) • Acromial end of the clavicle articulates with
▪ Moving acromial end along circular acromion of the scapula
path (circumduction) • Articular surface (covered with
fibrocartilage) – separated by incomplete
Blood Supply of SC Joint
wedge – shaped articular
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REYES, BERDIN, MALATE
S1| HUMAN ANATOMY
CE
DRA. MARIA LUISA PARLADE | 10 04-05 21
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2025

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JOINT CAPSULE OF THE AC JOINT
•

•
Associated with motion at the physiological
scapulothoracic joint
No muscles connect the articulating bone to

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move the AC joint
• Caused by the Axio-appendicular muscle
(attach and move the scapula)

Blood Supply and Nerve Supply of AC Joint

Blood Supply: Suprascapular and Thoracoacromial

arteries

Nerve Supply: Lateral Pectoral and Axillary Nerves

• Hilton’s Law (Joints are supplies by articular

branches of the nerves supplying the
muscles that act on the joints)
• Sleeve-like, relatively loose fibrous layer is
• Subcutaneous Location: no muscles cut
attached to margins of articular surfaces
across the joint
• Synovial membrane – lines the fibrous layer
▪ Innervation is also provided to the AC
• Strengthen superiorly by fibers of the
Joint by cutaneous lateral
trapezius (relatively weak)
supraclavicular nerve (typical of the
Ligaments of the AC Joints distal limb)

• Fibrous band extending from the acromion

to the clavicle BURSAE IN THE SHOULDER JOINT
• Strengthen the AC joints superiorly
Subscapular Bursae
• Integrity of the joint – maintained by
extrinsic ligament (distant from the joint) • Between the tendon and subscapularis and
CORACOCLAVICULAR Ligament neck of the scapula
• Protects the tendon where it passes inferior
• Strong pair of bands to the root of the coracoid process and over
• Unites the coracoid process of scapula to the neck of the scapula
clavicle • Communicatees with the joint cavity
• Consist of two ligament: through an opening in the capsule
▪ Conoid Ligament
Subacromial Bursae
- Inverted triangle
- Apex inferiorly attached to the root of • The acromion, coracoacromial ligament and
the coracoid process deltoid – superiorly
- Wide attachment-conoid tubercle on • Supraspinatus tendon and joint capsule
the inferior surface of the clavicle inferiorly
▪ Trapezoid Ligament • Facilitates movement on the supraspinatus
- Attached to superior surface of the tendon under the coracoacromial arch and
coracoid process the deltoid
- Extends laterally to the trapezoid line • Does not communicate with the joint cavity
on the inferior surface of the clavicle
• Provides mean by which scapula and free
limb are suspended from the clavicular strut
(passively)

MOVEMENT OF THE AC JOINT

• Acromion of the scapula rotates the

acromial end of the clavicle

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REYES, BERDIN, MALATE
S1| HUMAN ANATOMY
CE
DRA. MARIA LUISA PARLADE | 10 04-05 21
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2025

|\
BURSAE IN THE SHOULDER JOINT
• SUBSCAPULAR BURSAE
- Between the tendon of subscapularis and
MUSCLES OF PECTORAL AND SCAPULAR REGIONS
• Anterior axio-appendicular muscles
-Moves the pectoral girdle

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neck of the scapula -Four: pectoralis major, pectoralis minor,
- Protects the tendon where it passes subclavius, and the serratus anterior
inferior to the root of the coracoid process ➢ Pectoralis minor
and over the neck of the scapula - Stabilizes the scapula and is used
when stretching the upper limb
• SUBACROMIAL BURSAE
toward to touch an object that is
- The acromion, coracoacromial ligament
out of reach
and deltoid- superiorly - Also assists in the elevating the
- supraspinatus tendon and joint capsule ribs for deep inspiration when the
inferiorly pectoral girdle is fixed or elevated
- facilitates movement of the supraspinatus - Lies in the anterior wall of the
tendon under the coracoacromial and axilla
deltoid - Useful anatomical and surgical
- Does not communicate with the joint landmark for structures
cavity - Almost completely covered by the
pectoralis major
- Triangular shape
- Base proximal attachment :
formed by fleshy slips attached to
the anterior ends of the 3rd to 5th
ribs near the costal cartilages
- Apex (distal) attachment : on the
coracoid process of the scapula

➢ Pectoralis Minor
- Has clavicular and sternocostal
heads
- when acting together: produces
powerful adduction and medial
rotation
- Clavicular hear: flexes the
humerus
-Sternocostal head: extends the
humerus
- Large, fan-shaped muscles
- Covers the superior part of the
thorax
- Forms the narrow deltopectoral
groove with the adjacent deltoid
muscles.
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REYES, BERDIN, MALATE
S1| HUMAN ANATOMY
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DRA. MARIA LUISA PARLADE | 10 04-05 21
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2025

|\ muscles to use it as a fixed bone for

movements of the humerus
- Overlies the lateral part of the
thorax and forms the medial wall of

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the axilla
- From latin serratus “a saw” – saw-
toothed appearance of its fleshy
slips or digitations

➢ Subclavius
- Lies almost horizontally when the
arm is in the anatomical position
- Small, round muscles
- Located inferior to the clavicle-
protects the subclavian vessels and
the superior trunk of the bronchial
plexus if the clavicle fractures
- Anchors and depresses the
clavicle; stabilizes it during
movements of the upper limb
- Helps resist tendency for the
clavicle to dislocate at the
sternoclavicular joint.

• Postero Axio-Appendicular

➢ Trapezius
- Direct attachment of the pectoral
girdle to the trunk
- Large, triangular muscle covering
the posterior aspect of the neck and
the superior half of the trunk
- Attaches the pectoral girdle to the
➢ Serratus anterior
cranium and vertebral column
- One of the most powerful muscle
- Drooping of shoulders- caused by
in the pectoral girdle
weakness of the trapezius
- Strong protractor of the scapula:
used when punching or reaching
anteriorly
- “boxer’s muscle” holds the scapula
against the thoracic wall when
doing push ups or when pushing
against resistance
- Strong inferior part of the serratus
anterior rotates the scapula
(elevating its glenoid cavity so the
arm can be raised above the
shoulder ); also anchors the scapula,
keeping its closely applied to the
thoracic wall- enabling other

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REYES, BERDIN, MALATE
S1| HUMAN ANATOMY
CE
DRA. MARIA LUISA PARLADE | 10 04-05 21
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2025

|\ ➢ Latissimus dorsi
-Latin for “widest of back”- muscle
covers wide area of the back
- Extend retracts, and rotates the
- Deltoid, teres major, teres minor,
supraspinatus, infraspinatus, and
subscapularis

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humerus medially (e.g. folding your • Deltoid
arms behind your back, scratching -Thick, powerful, coarse-textured muscles
the skin over the opposite scapula) covering the shoulder and forming its round
- Along with the pectoralis major, it contour
is a powerful adductor of the - Shaped like the inverted Greek Letter delta
humerus; plays a major role role in Δ
downward rotation of the scapula; - Divided into unipennate anterior and
raises trunk to the arm (pull ups, posterior parts and a multipennate
swimming, paddling) middle part
- Restores the upper limb from the - Can act separately or as a whole
abduction superior to the shoulder- - When all three parts contract
important in climbing simultaneously, arm is abducted
-Anterior and Posterior parts- used to
swing the limbs while walking
-Anterior part- assist the pectoralis major
in flexing the arm
- Posterior part- assist the latissimus
dorsi in extending the arm

• Rhomboids
-Major and minor- not always clearly
separated from the one another; form an
oblique equilateral parallelogram
-Rhomboid major- thin and flat but two
times wider
-Rhomboid minor- thicker; superior to the
rhomboid major.
-Retract and rotate the scapula; also assist
the serratus anterior in holding the scapula
against the thoracic wall, and fixing the
scapula during movements of the upper
limb
- Used when forcibly lowering the raised
upper limbs
• Teres Major
-Adducts and medially rotates the arm
- Extends the arm from the flexed position
- Thick rounded muscle passing laterally
from the inferolateral third of the scapula

• Scapulohumeral (Intrinsic shoulder)

Muscles
-Relatively short muscles that pass from the
scapula to the humerus to act on the
glenohumeral joint
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REYES, BERDIN, MALATE
S1| HUMAN ANATOMY
CE
DRA. MARIA LUISA PARLADE | 10 04-05 21
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2025

|\• Rotator cuff muscles (SITS)

-Form the musculotendinous rotator cuff
- All EXCEPT the supraspinatus are rotators
-Nerve supply – most clearly distinguished
the teres minor from the infraspinatus
=Teres minor- supplied by the axillary nerve
=Infraspinatus- supplied by the

|
of the humerus suprascapular nerve
• Supraspinatus
-Occupies the supraspinous fossa of the
scapula
- A bursa separates it from the lateral
quarter of the fossa
- Initiates and assist the deltoid in the first
15 of ABDUCTION
- To test supraspinatus (or the
suprascapular nerve: Abduction of arm is
attempted from a fully adducted • Subscapularis
- position against resistance, while the -Thick triangular muscle that lies on the
muscle is palpated superior to the spine of costal surface of the scapula
the scapula - Forms part of the posterior wall of the
axilla
- Primary medial rotator of the arm : also
adducts the arm
- along with the other rotator cuff muscle in
holding the head of the humerus in the
glenoid cavity during all movements of the
glenohumeral joint ( stabilize the joint
• Infraspinatus during movements of the elbow, wrist and
-Occupies the medial three quarters of the hand)
infraspinous fossa
- Partly covered by the deltoid and trapezius
- Powerful lateral rotator of the humerus
- Also helps stabilize the glenohumeral joint
- To test infraspinatus (or the suprascapular
nerve):
The person flexes the elbow and adducts
the arm
- The arm is then laterally rotated against
resistance
- If acting normally, the muscle can be
palpated inferior to the scapular spine

• Teres minor
- Narrow, elongate muscle
- Completely hidden by the deltoid; often
not clearly delineated from the
infraspinatus
- Works with the infraspinatus to rotate the
arm laterally and assist in its adduction

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2025

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|
BICIPITAL TENOSYNOVITIS
Legend: Red- arteries; Blue – vein

Increased color flow signal

Neovascularization
(+) Fluid filled

BICEPS TENDON SUBLUXATION

Empty groove
Biceps tendon displaced
(+) fluid in tendon sheath

ORIGIN: Supraspinous fossa of the scapula

INSERTION: Greater tuberosity of the humerus

FACETS OF THE GREATER TROCHANTER

Note: Teres minor inserted in inferior facet

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REYES, BERDIN, MALATE
S1| HUMAN ANATOMY
CE
DRA. MARIA LUISA PARLADE | 10 04-05 21
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2025

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SUPRASPINATUS •
•
Abducts arm while in internal rotation
Supraspinatus and bursa is seen passing
through the deep coracoacromial arch

|
LONG AXIS: Parrot/ Bird Beak Sign

SHORT AXIS: Tire on a wheel sign ORIGIN: Lateraal border of the scapula
INSERTION: Inferior facet of the greater tuberosity

If there is impartment it will not go in

Suprasipinatus is the most common injured part

SUBSCAPULARIS

SUPRASPINATUS PARTIAL TEAR

Hypoechoic area
Tendon non-retracted and visualized on both sides
of the tear ORIGIN: Subscapular fossa of the scapula
INSERTION: Lesser tuberosity of the humerus

AC JOINT

SUPRASPINATUS UNDER THE ACROMION

• Place probe at the acromion

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REYES, BERDIN, MALATE
S1| HUMAN ANATOMY
CE
DRA. MARIA LUISA PARLADE | 10 04-05 21
BATCH
2025

|\ SURFACE ANATOMY OF PECTORAL,

SCAPULAR, AND DELTOID REGIONS

|
• Clavicle

- boundary demarcating the root of the neck

from the thorax
- Also indicates the “divide” between the
deep cervical and axillary lymph sheds

• Infraclavicular fossa

- depressed area inferior to the lateral part of

the clavicle
- Overlies the clavipectoral (deltopectoral)
triangle – bounded by the clavicle
superiorly, the pectoralis major medially,
• Painted seated arm at the side and the deltoid laterally
• Probe on top at AC joint
• UMBRELLA SIGN • Coracoid process of the scapula
- used as a bony landmark when performing a
brachial plexus block,; position is important
in diagnosis of shoulder dislocations
- Tip of the process can be felt on deep
palpation on the lateral aspect of the
clavipectoral triangle

ACROMIOCLAVICULAR JOINT SEPARATION

• Marked widening of joint space

• >4mm widening

ROTATOR CUFF

SURFACE ANATOMY OF PECTORAL,

SCAPULAR, AND DELTOID REGIONS
• Trapezius
SUBACROMIAL SUBDELTOID BURSITIS
- Can be felt when anterior sloping border is
palpated while lifting a weight
• Sternocostal part of the pectoralis major
- Can be seen and palpated when arm is
abducted and adducted against resistance

• Anterior axillary fold

• SASD is distended and filled with fluid/ - When grasped between the fingers and
Bursa is filled with fluid thumb, will let the inferior border of the
sternocostal head of the pectoralis major
can be felt

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S1| HUMAN ANATOMY
CE
DRA. MARIA LUISA PARLADE | 10 04-05 21
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2025

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•

•
Several digitations of the serratus anterior are
visible inferior to the anterior axillary fold
Posterior axillary fold
- When forearm is force backwards when in it
is in its abduction, lateral rotation and
extension

|
- Composed of skin and muscular tissue
(latissimus dorsi and teres major, bounding 2. Posterior Dislocations
the axilla posteriorly) - Direct force to the front of the joint
• Spine of the scapula (medial)
- Subcutaneous; easily palpated because it
extends medially and slightly inferiorly from
the acromion
• Root of the scapular spine
- Located apposite the tip of the T3 spinous
process
• Greater tubercle of the humerus
- Is the most lateral bony point in the
shoulder when the arm is adducted, and
may felt on deep palpation through the
deltoid inferior to the lateral border of the
acromion
• Deltoid
- Usually visible when the arm is abducted
against resistance
- Loss of the rounded muscular appearance
of the shoulder, and the appearance of a
surface depression distal to the acromion,
are characteristic of a dislocated shoulder,
or dislocation of the glenohumeral joint due
to the displacement of the humeral head
• Teres major AXILLA
- Rotated against resistance (as when a Pyramid – shaped space between upper part of arm
gymnast stabilizes or fixes the shoulder joint and side of chest
during an iron cross maneuver on the rings)
• Rhomboids - Inferior to the glenohumeral joint of the
- Palpated when the upper limbs are arm and thorax
abducted because of the lateral movement - Passage for nerves blood and blood vessels
of the scapulae on the thoracic wall that serve the upper limb
- Not always visible - Protected by the adducted upper limb
which has a ticle reflex that rapidly and
Stability of the Shoulder Joint instinctively resumes the protected position
• Unstable – shallow glenoid fossa and weak when invaded
ligaments
• Most commonly dislocated KEY MUSCLES IN AXILLA
• Strength – depends on the tone of rotator PECTORALIS MINOR MUSCLE
cuff muscles
- Tendons of these muscles are fused to the - Triangular beneath the pectoralis major
underlying capsule of shoulder - Crosses the axillary artery and brachial
plexus
Dislocations:
CLAVIPECTORAL FASCIA
1. Anterior Inferior Dislocation
- Sudden force on humerus with joint fully - Strong sheet of connective fascia attached
abducted above to the clavicle
- Yilts the humeral head downward onto the - Below, splits to enclose pectoralis minor
inferior weak part of the capsule
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REYES, BERDIN, MALATE
S1| HUMAN ANATOMY
CE
DRA. MARIA LUISA PARLADE | 10 04-05 21
BATCH
2025

|\- Continuous downward as suspensory

ligament of the axilla and joins fascial floor
of the armpit

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