Shoulder AnatomyShoulder Anatomy

Shoulder Anatomy - bonesShoulder Anatomy - bones

• Scapula• Clavicle• Humerus

• greater tubercle

ScapulaScapula

Subscapularfossa

Infraspinous fossa

Inferior angle

Axillaryborder

Supraspinousfossa

Humerus

Shoulder AnatomyShoulder Anatomy

Joints of the shoulder

• Sternoclavicular (SC) Joint

• Acromioclavicular (AC) Joint

• Glenohumeral (GH) Joint

• Scapulothoracic Articulation

Sternoclavicular (SC) JointSternoclavicular (SC) Joint

• Synovial Joint - double gliding joint

• side to side & front to back

• Ligaments• Anterior SC• Posterior SC• Interclavicular• Costoclavicular

SC MovementsSC Movements

• moves in many directions (but only in small amounts)• Protraction• Retraction• Elevation• Depression

SC Joint FunctionSC Joint Function

• Absorbs forces• Distributes forces• Allows movement of

clavicle

Shoulder Anatomy - jointsShoulder Anatomy - joints

• Acromioclavicular

Injury –

“Separated

Shoulder”

Acromioclavicular joint (AC)Acromioclavicular joint (AC)Support a. Capsule - dense but

weak b. Acromioclavicular

ligaments• Superior and

inferior c. Coracoclavicular

ligaments• Trapezoid-

Lateral• Conoid -Medial

AC JointAC Joint

Acromioclavicular JointAcromioclavicular Joint

• A-C Ligament: strengthens A-C joint

along with fibers from

trapezius

• Coracoclavicular Ligament: anchors

Clavicle to coracoid

process; strongest

ligament binding the

clavicle to scapula

Coracoclavicular LigamentCoracoclavicular Ligament

• Two Parts• Conoid ligament

(medial)

• Trapezoid (lateral)

• A-C Separation 1-Stretch A-C

2-Complete tear of A-C; partial

tear of C-C

3-Complete tear of A-C; complete

tear of C-C

Shoulder Anatomy - jointsShoulder Anatomy - joints

• Scapulothoracic• muscular

attachments only• The scapula meets

the rib cage!

Scapulothoracic ArticulationScapulothoracic Articulation

• Movements:• Protraction• Retraction• Elevation• Depression• Upward Rotation• Downward Rotation

Shoulder Anatomy - jointsShoulder Anatomy - joints

• Glenohumeral• ball and socket

• lacks bony stability (small glenoid, large humerus)

• provides motion

• glenoid labrum (fibrocartilage)• rotator cuff (muscular stability)

ROTATOR CUFFROTATOR CUFF

Glenohumeral (GH) JointGlenohumeral (GH) Joint• “True Shoulder Joint”

• Synovial Joint - Ball and Socket

• Glenoid fossa & labrum with Humeral Head

• 3 Major Ligaments:• Coracohumeral - coracoid to greater

tubercle (strong)

• 3 GH bands - thickenings of articular capsule

• Transverse Humeral - greater to lesser tubercle

Glenohumeral Glenohumeral StabilityStability

• Glenoid Cavity

(shallow)

• Glenoid labrum (soft

cartilaginous rim that

adds depth and

stability)

GH Joint SupportGH Joint Support• Capsule • Ligaments

• Anterior – Glenohumeral

• Superior - Coracohumeral

• Coracoacromial arch• Bursae

• Subacromial

• Subdeltoid

• Subscapular bursa

Coracohumeral ligament

Glenohumeral ligaments

Glenohumeral StabilityGlenohumeral Stability

• Anterior Capsule

• Posterior Capsule

• Glenohumeral

ligaments

• Superior

• Middle

• Inferior

GH MovementsGH Movements

• Sacrifices stability for mobility• Flexion• Extension• Abduction• Adduction• Internal Rotation• External Rotation

Upper Arm & Shoulder MusclesUpper Arm & Shoulder Muscles

triceps brachiitriceps brachii

deltoiddeltoid

teres majorteres major teres minorteres minor

brachialisbrachialis

Rotator Cuff MusclesRotator Cuff Muscles

supraspinatussupraspinatus

subscapularissubscapularisinfraspinatusinfraspinatus teres minorteres minor