PS 1001:03 Lecture Notes - Lecture 17: Latissimus Dorsi Muscle, Serratus Anterior Muscle, Pectoralis Minor Muscle
Discuss and describe concomitant movements of all the joints
Scapulothoracic
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Acromioclavicular
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Sternoclavicular
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Joints involved
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Requires smooth integration of all joints, function simultaneously
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All move alongside GH joint to produce fluid movement
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Plane of scapula runs obliquely in an anteroposterior (front to back) and mediolateral (spine to
side) direction to form an angle of 30 degs with the frontal plane
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Scapula glides over thorax wall, moves over scapula plane (because 30 degrees, not frontal or
medial for example)
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Concomitant movements
Mobility of scapula essential for the freedom of movement of the upper limb
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Scapulothoracic: glenohumeral movement
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Elevation of arm 2:1
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Ratio different from person to person
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Depends on what is normal for the individual
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Scapulo-humeral rhythm
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Is scapula producing abnormal movement? -> indicates problem with muscles around scapula
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Active and associated movements between scapula and upper thorax
Pectoral girdle - supported, stabilised and propelled by muscles that attach to the ribs, sternum
and vertebrae
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Scapula moves on thoracic wall at the conceptual "scapulothoracic joint"
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Elevation
Superior trapezius
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Levator scapulae
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rhomboids
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Depression
Pectoralis minor
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Inferior trapezius
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Serratus anterior (inferior part)
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Protraction
Pectoralis minor
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Serratus anterior
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Retraction
Rhomboids
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Middle trapezius
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Latissimus dorsi
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Lateral rotation (elevating glenoid cavity)
Upper trapezius
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Lower trapezius
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Medial rotation (depressing glenoid cavity)
Pectoralis minor
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Levator scapulae
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Latissimus dorsi
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MUST KNOW ATTACHMENTS OF ALL THESE MUSCLES
Movement of scapula
L1 - scapulothoracic complex muscle imbalance
Monday, 23 April 2018
4:12 PM
wk 9 Page 1
Clavicle attached via acromioclavicular joint and conoid and trapezoid ligaments
(coracoacromial ligaments)
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30 degrees of rotation about long axis of clavicle can occur at these joints
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Simultaneous movements occur in clavicle, which acts as strut to prevent scapula moving medially
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Clavicle can elevate, depress and rotate
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As arm abducted beyond 90 degs-> clavicle rolls upwards and backwards, and clavicular joints
elevated
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If sternal end depresses, acromial end elevates
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Can protract and retract if sternal end protracts, acromial end retracts and vice versa
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Movements at acromial/lateral end of clavicle mimicked by scapula
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Greatest movements : elevation and depression at distal end, with small gliding movements at
medial end
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Summary of movement and limiting structures
Know attachments of muscles so can understand role
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Screen clipping taken: 23/04/2018 10:51 PM
wk 9 Page 2
