Download Shoulder region

Shoulder region
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Bones
Joints
Muscles
Vessels & Nerves
Classifications of muscles that move
the shoulder
• A. muscles connecting scapula to humerus
• B. muscles connecting trunk to scapula
• C. muscles connecting trunk to humerus
Biceps & Triceps tendons
A. muscles connecting scapula to humerus
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6.
7.
Supraspinatus
Infraspinatus
Teres minor
Subscapularis
Teres major
Coracobrachialis
Deltoid
Short muscles
• Function:
abduction
Subscapularis
• Function: Int. rotation
Rotator Cuff
• Rotator cuff function:
• only 25% of the humeral head is in contact with the
glenoid fossa.
• The rotator cuff muscles compress and depress the
humeral head within the glenoid fossa.
Rotator Cuff Disease photo
Quiz
supraspinatus
infraspinatus
teres minor
subscapularis
Teres major
• Origin:
– Inf angle of scapula
• Insertion:
– Med lip of groove
• Actions:
– Internal rotation and
adduction of arm
• Function:
adduction of humerus
med rotator
• Why medial?
Coracobrachialis
• Function:
flex & adduct
the shoulder joint
Deltoid
• Origin:
– Clavicle, scapula
• Insertion:
– Deltoid tuberosity of
humerus
• Actions:
– Abduction
– Anterior deltoid: internal
rotation
– Posterior deltoid:
external rotation
Classifications of muscles that move
the shoulder
• A. muscles connecting scapula to humerus
• B. muscles connecting trunk to scapula
• C. muscles connecting trunk to humerus
B. muscles connecting trunk to scapula
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2.
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6.
Serratus anterior
Levator scapula
Rhomboid major
Rhomboid minor
Trapezius
Pectoralis minor
Serratus Anterior
• Origin:
– Ribs
• Insertion:
– Medial border of
scapula
• Actions:
– Protraction and
rotation of scapula
Winged scapula
Levator scapula
• Origin:
– Cervical vertebrae
• Insertion:
– Scapula
• Action:
– Elevation of the scapula
Rhomboid major and minor
• Origin:
– Cervical and Thoracic
vertebrae
• Insertion:
– Scapula
• Actions:
– Retraction
– Elevation
Trapezius
• Origin:
– Occipital bone of skull,
cervical and thoracic
vertebrae
• Insertion:
– Clavicle and Scapula
• Actions:
– Elevation
– retraction
Pectoralis Minor
• Origin:
– Ribs
• Insertion:
– Coracoid process of
scapula
• Action:
– Depression of scapula
Depression of scapula
Classifications of muscles that move
the shoulder
• A. muscles connecting scapula to humerus
• B. muscles connecting trunk to scapula
• C. muscles connecting trunk to humerus
C. muscles connecting trunk to humerus
• Pectoralis major
• Latissimus dorsi
Pectoralis Major
• Origin:
– Clavicle, sternum, upper
ribs
• Insertion:
– Crest of greater tubercle
and lat lip
• Action:
– Add, med rotation
Latissimus Dorsi
• Origin:
– Vertebrae, sacrum,
ilium
• Insertion:
– Medial lip
• Actions:
– Adduction and med
rotation of humerus
Latissimus Dorsi if humerus is fixed
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Covering th front and back of the trunk.
The pectoralis major and latissimus dorsi both adduct and medially rotate the
Humerus.
Lower edge of the pectoralis major muscle on rib 7 = upper edge of the latissimus dorsi
on vertebra T7.
Shoulder Girdle Movements