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T H E G L E N O H U M E R A L ( G H ) J O I N T
THE SHOULDER JOINT
CLARIFICATION OF TERMS
• Shoulder girdle = scapula and clavicle
• Shoulder joint (glenohumeral joint) = scapula and
humerus
Lippert, p115
OSTEOLOGY OF THE GH JOINT(BONES)
• Scapula
• Glenoid fossa
• Glenoid labrum
• Subscapular fossa
• Infraspinous fossa
• Supraspinous fossa
• Axillary border
• Acromion process
(Vertebral)
(Axillary)
(Axillary)
(Vertebral)
Scapula (Dorsal aspect)
OSTEOLOGY OF THE GH JOINT(BONES)…CONT
• Humerus
• Head
• Surgical neck
• Anatomical neck
• Shaft
• Greater tubercle
• Lesser tubercle
• Deltoid tuberosity
• Bicipital groove
• Bicipital ridges
Intertubercular groove
(Bicepital groove)
(Posterior aspect)
Intertubercular Groove (bicepital groove)
Deltoid Tuberosity
Anatomical Neck
JOINT STRUCTURE OF THE GH JOINT
• Ball and socket joint
• Movement in all three planes (3 degrees of
freedom)
• Articulation between the humeral head of the
humerus and the glenoid fossa of the scapula
• One of the most movable joints in the body and,
consequently, one the _______________ stable.
Lippert, p131
JOINT MOVEMENT OF THE GH JOINT
• Osteokinematics • Flexion
• Extension
• Hyperextension
• Abduction
• Adduction
• Medial rotation (internal rotation)
• Lateral rotation (external rotation)
• Horizontal abduction
• Horizontal adduction
• Circumduction
• Scaption
VISUAL EXERCISE:
• Watch your partner perform the following
movements and guesstimate the degrees of motion
for each of the following:
• Shoulder flexion:___________
• Shoulder hyperextension:____________
• Shoulder abduction:___________
• Shoulder internal rotation:__________
• Shoulder external rotation:_________
JOINT MOVEMENT OF THE GH JOINT…CONT
• Arthrokinematics
• Concave-convex rule
• The convex humeral head moves within the concave glenoid
fossa
• The convex joint surface (humeral head) moves in a direction
opposite to the movement of the body segment (humeral shaft)
• Flexion – humeral head glides _____________________
• Abduction – humeral head glides _____________________
• Extension – humeral head glides _____________________
• Adduction – humeral head glides _____________________
• Internal rotation – humeral head glides _____________________
• External rotation – humeral head glides _____________________
Lippert, p132
JOINT MOVEMENT OF THE GH JOINT…CONT
• Arthrokinematics
• The articular surface of the humeral head is greater than that of the glenoid fossa
• If the humeral head simply rotated in the glenoid fossa, it
would run out of articular surface before full abduction
occurred
• So, as abduction occurs, the humeral head rolls across the
glenoid fossa and glides inferiorly (thanks to the rotator cuff)
• Complete abduction can occur only with full external
rotation
SUPPORTING STRUCTURES OF THE GH JOINT
• Rotator cuff • SITS muscles surround humeral head and actively hold it
against the glenoid fossa
• Capsular ligaments • Relatively loose capsule attaches the rim of the glenoid fossa
and anatomic neck of the humerus
• Coracohumeral ligaments • Connects coracoid process and anterior side of greater
tubercle
• Glenoid labrum • A fibrocartilaginous ring that encircles the rim of the glenoid
fossa, deepening the socket and sealing the joint
• Long head of the Biceps • The proximal portion of the tendon wraps around the superior
aspect of the humeral head, providing anterior stability
Mansfield, p58
MYOLOGY OF THE GH JOINT (MUSCLES)
• Deltoid
• Pectoralis major
• Latissimus dorsi
• Teres major
• Supraspinatus
• Infraspinatus
• Teres minor
• Subscapularis
• Coracobrachialis
• Biceps brachii
• Triceps brachii, long head
Deltoid: Anterior
Origin Anterior surface of the lateral
aspect of the clavicle
Insertion Deltoid tuberosity of the humerus
Action Sh flexion, HADD, Sh IR, Sh ABD
Innervation Axillary n.
Anterior
Lippert, p136
…strengthen the anterior deltoid • Concentrically?
Deltoid: Middle
Origin Superior lateral surface
of the acromion
Insertion Deltoid tuberosity of the
humerus
Action Sh ABD, Sh flexion
Innervation Axillary n.
Middle Deltoid
Lippert, p136
Deltoid: Posterior
Origin Spine of the scapula
Insertion Deltoid tuberosity of the
humerus
Action Sh extension, HABD, Sh
ER
Innervation Axillary n.
Lippert, p136
Pectoralis Major
Origin Clavicular portion: anterior
margin of the medial portion of
the clavicle
Sternal portion: lateral margin
of the manubrium and body of
the sternum and cartilage of
the first 6-7 ribs
Insertion Crest of the greater tubercle of
the humerus
Action Clavicular: Shoulder flexion, IR
and Horiz ADD
Sternal: Sh IR, Sh ADD, Sh
extension to anatomic position
Innervation Clavicular: lateral pectoral n.
Sternal: lat & medial pectoral n. Mansfield, p82
…stretch the pectoralis major?
…strengthen the pectoralis major
eccentrically?
Latissimus Dorsi
Origin Thoracolumbar fascia, spinous
processes of lower thoracic and
lumbar vertebrae, posterior iliac
crest, lower 4 ribs and inferior angle
of scapula
Insertion
Floor of intertubercular groove of
humerus
Action Sh ADD, Sh extension, Sh IR, scapular
depression
Innervation Thoracodorsal n.
“tidbit” Necessary for “crutchwalking” and
transfers!
Lippert, p137
…stretch the latissimus dorsi?
Teres Major
Origin Inferior angle of the scapula
Insertion
Crest of the lesser tubercle of the
humerus
Action Sh ADD, Sh extension, Sh IR
Innervation Lower scapular n.
Lippert, p138
SITS
• Supraspinatus
• Infraspinatus
• Teres Minor
• Subscapularis
Supraspinatus
Origin Supraspinous fossa of the
scapula
Insertion
Greater tubercle of the
humerus
Action Sh ABD, stabilization of the
GH, slight ER
Innervation Suprascapular n.
“Tidbit” One of the rotator cuff
muscles
Lippert, p138
Infraspinatus
Origin Infraspinous fossa of the
scapula
Insertion
Greater tubercle of the
humerus
Action Sh ER, stabilization of the
GH joint
Innervation Suprascapular n.
“tidbit” One of the rotator cuff
muscles
Lippert, p138
Teres Minor
Origin Posterior lateral
border of the scapula
near the inferior
angle
Insertion
Greater tubercle of
the humerus (inferior
to the infraspinaus)
Action Sh ER, stabilization of
the GH joint
Innervation Axillary n.
Lippert, p139
Subscapularis
Origin Subscapular fossa of the
scapula
Insertion
Lesser tubercle of the
humerus
Action Sh IR, stabilization of the
GH joint
Innervation Upper and lower
subscapular n.
“tidbit” One of the rotator cuff
muscles
Lippert, p140
Coracobrachialis
Origin Coracoid process of the scapula
Insertion Medial aspect of the proximal
shaft of the humerus
Action Assists with Sh flexion & add
Innervation Musculocutaneous n.
Lippert, p140
Biceps Brachii
Origin Long head: supraglenoid tubercle of
glenoid fossa
Short head: coracoid process of the
scapula
Insertion Radial tuberosity of the radius
Action Sh flexion, elbow flexion, forearm
supination
Innervation Musculocutaneous n.
“tidbit” The actions of the biceps brachii are
“perfect” in combination for opening a
bottle of wine. “The Corkscrew effect”
Biceps
Brachii
Mansfield, p78
…strengthen the biceps brachii
isometrically?
…stretch the biceps brachii?
Long Head of the Triceps Brachii
Origin Infraglenoid tubercle of the
scapula
Insertion Olecranon process of the
ulna
Action Sh extension, elbow
extension
Innervation Radial n.
Mansfield, p80
MYOLOGY OF THE GH JOINT (MUSCLES)…CONT
• Anatomical Relationsips • Muscles that stabilize are deep to muscles that move.
• Therefore, glenohumeral joint muscles are superficial to shoulder girdle muscles
• Deltoid: forms a superficial cap over the anterior, lateral and posterior sides of the shoulder
• Anteriorly, pectoralis major covers most of the superficial chest wall
• Biceps brachii and triceps brachii encompass most of the anterior and posterior arm, respectively
• If the trapezius were removed, you would see the supraspinatus above the scapular spine and in descending order, the infraspinatus, teres minor and teres major below the scapular spine
• The latissimus dorsi covers the lumbar and lower thoracic region of the back
Lippert, p140
MYOLOGY OF THE GH JOINT (MUSCLES)…CONT
• Anatomical Relationsips
Lippert, p140
MYOLOGY OF THE GH JOINT (MUSCLES)…CONT
• Summary of Muscle Action:
Action Muscles
Flexion Anterior deltoid, pectoralis major (clavicular)
Extension Posterior deltoid, lattisimus dorsi, teres major,
pectoralis major (sternal)
Hyperextension Latissimus dorsi, posterior deltoid
Abduction Deltoid, supraspinatus
Adduction Pectoralis major, teres major, latissimus dorsi
Horizontal abduction Posterior deltoid, infraspinatus, teres minor
Horizontal adduction Pectoralis major, anterior deltoid
Lateral rotation Infraspinatus, teres minor, posterior deltoid
Medial rotation Latissimus dorsi, teres major, subscapularis,
pectoralis major, anterior deltoid
(Lippert, p142)
MYOLOGY OF THE GH JOINT (MUSCLES)…CONT
• Summary of Muscle Innervation:
Lippert, p143
Muscle Nerve Segment
Subscapularis Upper and lower subscapular C5, C6
Teres major Lower subscapular C5, C6
Pectoralis major Lateral and medial pectoral C5, C6, C7 & C8, T1
Latissimus dorsi Thoracodorsal C6, C7, C8
Supraspinatus Suprascapular C5, C6
Infraspinatus Suprascapular C5, C6
Deltoid Axillary C5, C6
Teres minor Axillary C5, C6
Coracobrachialis Musculocutaneous C6, C7
Biceps Musculocutaneous C5, C6
triceps radial C7, C8
COMMON SHOULDER PATHOLOGY
• AC separation:
• Fractures:
• Shoulder dislocation and subluxation:
• Impingement:
• Adhesive Capsulitis:
• Rotator Cuff Tear:
• Bicipital Tendonitis:
PIN THE TAIL ON THE DONKEY
• Point to the…
• Shoulder flexors
• Shoulder extensors
• Shoulder abductors
What upper extremity muscles
can you identify on him?
Against Gravity
Position
Gravity
Eliminated
Position
Gravity Assisted
Position
Shoulder
Extensors
Shoulder
Abductors
Shoulder Internal
Rotators
During a push up, there is a raising of the
body and a lowering of the body. Identify
what type of contraction the muscle is
doing during each component of a push
up: • Isometric
• Concentric
• Eccentric
• No contraction
Raising the body Lowering the body
Biceps brachii
Triceps brachii
Protractors
Retractors
Abdominals
REFERENCES
• Lippert, L.S. (2011). Clinical Kinesiology and
Anatomy, 5th ed. Philadelphia, PA: F.A. Davis.
• Mansfield, P.J., & Neumann, D.A. (2009). Essentials of
Kinesiology for the Physical Therapist Assistant. St.
Louis, MO: Mosby Elsevier.
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