The shoulder Flashcards
Synarthrosis
Joint with no movement
Amphiarthrosis
Joint with little movement
Diarthrosis
Joint with a lot of movement (i.e., most synovial joints)
Nonaxial
No axis of movement (wrist)
Uniaxial
Single axis of movement (elbow)
Biaxial
2 axes of movement (flexion/extension adduction/abduction)
Multiaxial
> 2 axes of movement (shoulder)
Name of the shoulder joint
Glenohumeral joint
Characteristics of the Glenohumeral joint
Synovial joint
Diarthrotic
Multiaxial
Ball and socket
Bursae in the Shoulder
Subacromial bursa
Subdeltoid bursa
Subcoracoid bursa
Subscapular bursa
Subacromial bursa
Between acromion and supraspinatus tendon
Subdeltoid bursa
Between deltoid m. and joint capsule
Subcoracoid bursa
Between subscapularis m. and coracoid process
May be fused with subscapular bursa
Subscapular bursa
Between subscapularis m. and joint capsule, communicates with synovial cavity of joint.
Impingement Syndrom
Supraspinatus tendon (tendonitis) Can involve subacromial (bursitis)
Scapulohumeral musculature attached:
the scapula to the humerus
Function of scapulohumeral musculature
Move humerus at the shoulder joint and contribute to the stabilization of the joint
Innervation of the Scapulohumeral Musculature
All innervated by the brachial plexus
Rotator Cuff Muscles
Subscapularis
Supraspinatus
Infraspinatus
Teres minor
Proximal attachment of the Deltoid
Lateral 1/3 of clavicle, acromion, and spine of scapula
Distal attachment of the Deltoid
Deltoid tuberosity of humerus
Actions of the Deltoid
Flexes, medially rotates, abducts, extends, and laterally rotates humerus
Does NOT adduct
Innervation of the Deltoid
Axillary Nerve
Proximal attachment of Teres Major
Posterior surface of inferior angle of scapula
Distal attachment of Teres Major
Medial lip of intertubercular (bicipital) groove of humerus
Actions of Teres Major
Adducts and medially rotates humerus
Synergist with Latissamis dorsi
Innervation of Teres Major
Lower subscapular nerve
Proximal attachment of Supraspinatus
Supraspinous fossa of scapula
Distal attachment of Supraspinatus
Superior facet of greater tubercle of humerus
Actions of Supraspinatus
Works with deltoid in abduction of humerus, acts with other rotator cuff muscles in stabilizing shoulder joint
Innervation of the Supraspinatus
Suprascapular nerve
Proximal attachment of the Subscapularis
Subscapular fossa (anterior surface of scapula)
Distal attachment of the Subscapularis
Lesser tubercle of humerus
Actions of Subscapularis
Medially rotates and adducts humerus; helps hold humeral head in place
Innervation of Subscapularis
Upper and lower subscapular nerves
Largest and strongest of all the rotator cuff muscles
Subscapularis
True or False
Isolated subscapularis tears are relatively common.
False.
They are relatively rare
What can subscapularis injuries lead to?
Bicipital tendon instability and biceps tendonitis
Proximal attachment of Infraspinatus
Infraspinous fossa of scapula
Distal attachment of Infraspinatus
Middle facet of greater tubercle of humerus
Actions of the Infraspinatus
Laterally rotates humerus, helps hold humeral head in place
Innervation of the Infraspinatus
Suprascapular nerve
Proximal attachment of Teres minor
Middle part of lateral border of scapula
Distal attachment of Teres minor
Inferior facet of greater tubercle of humerus
Actions of Teres minor
Laterally rotates humerus, helps hold humeral head in place
Innervation of Teres minor
Axillary nerve
Common injury in elderly people
Tear in supraspinatus
Causes of Rotatory Cuff Injuries
Repetitive overhead activites:
Tennis, swimming, pitching, stacking boxes, painting, construction work.
Other causes:
Bone spurs, anatomical variation of the acromion
The two large named arteries that have tributaries that provide blood to the pectoral, shoulder, and axillary regions
Subclavian artery and axillary artery
Origin of the Subclavian artery
Right: Brachiocephalic trunk
Left: Aortic arch
Where does the subclavian artery arise?
Posterior to sternoclavicular joint
Where is part 1 of the subclavian artery in relation to the anterior scalene muscle?
Medial to the anterior scalene muscle
Where is part 2 of the subclavian artery in relation to the anterior scalene muscle?
Posterior to the anterior scalene muscle
Where is part 3 of the subclavian artery in relation to the anterior scalene muscle?
Lateral to the anterior scalene muscle
Branches of the Thyrocervical Arterial Trunk
- Transverse cervical artery - superficial branch and deep branch (dorsal scapular artery) (See slide 45)
- Inferior thyroid artery
- Ascending cervical artery
- Suprascapular artery
Where does the subclavian artery become the axillary artery?
Lateral border of first rib
Branches of the Scapular Anastomoses (Also see slide 48)
- Suprascapular artery
- Dorsal scapular artery
- Posterior intercostal arteries
- Circumflex scapular artery
- Thoracodorsal artery
Within the superficial back (posterior axio-appendicular) and scapular regions (scapulohumeral) there are named spaces and triangles that illustrate relationships among muscles, vessels, and nerves.
- Triangle of Auscultation
- Quadrangular Space
- Triangular Space
- Triangular Interval
Quadrangular Space
Axillary nerve and posterior circumflex humeral artery
Triangular Space
Circumflex scapular artery
Triangular Interval
Deep brachial artery and radial nerve