Upper Extremity Flashcards
What are the 2 major bones that make up the pectoral girdle?
Clavicle
Scapula
What are the major features of the scapula?
Spine Coracoid process Acromion process Supraspinatus fossa Infraspinatous fossa Subscapular fossa Glenoid fossa Superior and inferior angles
What is the only joint connecting the upper limb to the axial skeleton?
Sternoclavicular joint
[attachment via anterior/posterior sternoclavicular ligaments; articular disc with 2 separate synovial cavities]
Other than sternoclavicular joint and glenohumeral joint, what other joint is associated with the pectoral girdle?
Acromioclavicular joint
[synovial joint, superior and inferior acromioclavicular ligaments, other ligaments connect the clavicle to coracoid process of scapula]
How are epaxial back muscles innervated?
By dorsal/posterior rami of spinal nn.
How are hypaxial back muscles innervated?
By ventral/anterior rami of spinal nn.
Are the most superficial, extrinsic muscles of the back considered epaxial or hypaxial?
Hypaxial
They are primarily involved in moving the upper limb
What 2 muscles are in the first layer of the superficial hypaxial muscles of the back?
Trapezius m.
Latissimus dorsi m.
What 3 muscles are in the second layer (intermediate layer) of the hypaxial muscles of the back?
Levator scapulae m.
Rhomboid minor m.
Rhomboid major m.
Origin of Trapezius
Medial 1/3 superior nuchal line, external occipital protuberance, nuchal ligament, spinous process of C7-T12
Insertion of trapezius m.
Lateral 1/3 of clavicle, acromion, and scapular spine
Innervation of trapezius m. (Motor and sensory)
Motor: Spinal accessory n. (CN XI)
Sensory: C3, C4 spinal nn.
What 3 actions does trapezius m. have on the scapula?
Elevation
Retraction
Upward rotation (relative to glenoid)
[trapezius is most important m. for shrugging motion]
Origin of latissimus dorsi m.
Spinous processes of T7-T12, thoracolumbar fascia, iliac crest, inferior 3-4 ribs
Insertion of latissimus dorsi m.
Floor of intertubercular sulcus of humerus
Innervation of latissimus dorsi m.
Thoracodorsal nerve (C6-C8)
Actions of latissimus dorsi m.
Extends humerus
Adducts humerus
Medial rotation of humerus
What is the significance of the triangle of auscultation?
Less tissue in this area of the back, easier to hear breath sounds
What are the borders of the triangle of auscultation?
Trapezius m.
Latissimus dorsi m.
Medial scapular border
Origin of levator scapulae m.
Transverse processes of C1-C4
Insertion of levator scapulae m.
Medial superior scapula
Action of levator scapulae m.
Elevates scapula and rotates it
Innervation of levator scapulae m.
Dorsal scapular n. (C5) and cervical spinal nn. C3-C4
Origin of rhomboid minor m.
Nuchal ligament, C7-T1 spinous processes
Insertion of rhomboid minor
Medial scapula at spine border
Innervation of rhomboid minor
Dorsal scapular n.
Origin or rhomboid major m.
Spinous processes T2-5
Insertion of rhomboid major m.
Medial scapular border
Innervation of rhomboid major m.
Dorsal scapular n.
Actions of rhomboid major and minor on scapula
Elevation
Retraction
Downward rotation (opposes trapezius m.)
Actions of levator scapulae on scapula
Elevation
Downward rotation
What muscles make up the rotator cuff?
Supraspinatus
Infraspinatus
Teres minor
Subscapularis
Does teres major m. Contribute to the rotator cuff?
NO, just teres minor m.
Insertion of teres major m.
Intertubercular sulcus of humerus
Actions of teres major m.
Adducts/medially rotates arm
Innervation of teres major m.
Subscapularis n.
Action of supraspinatus m.
Abduction of arm
Innervation of supraspinatus m.
Suprascapular n.
Action of infraspinatus m.
Lateral rotation of arm
Innervation of infraspinatus m.
Suprascapular n.
Action of teres minor m.
Lateral rotation of arm
Innervation of teres minor m.
Axillary n.
Action of subscapularis m.
Medial rotation of arm
Innervation of subscapularis m.
Subscapular n.
Origin/insertion/innervation/action for:
Trapezius m.
Origin: medial 1/3 superior nuchal line, external occipital protuberance, nuchal ligament, spinous process of C7-T12
Insertion: lateral 1/3 of clavicle, acromion, and scapular spine
Innervation: spinal accessory n. (motor), and sensory via C3,C4 spinal nn.
Action: elevation, retraction, and upward rotation of scapula
Origin/insertion/innervation/action for:
Latissimus dorsi m.
Origin: spinous processes of T7-12, thoracolumbar fascia, iliac crest, inferior 3-4 ribs
Insertion: floor of intertubercular sulcus of humerus
Innervation: thoracodorsal n. (C6-8)
Action: extension, adduction, and medial rotation of humerus
Origin/insertion/innervation/action for:
Levator scapulae m.
Origin: transverse processes of C1-4
Insertion: medial superior scapula
Action: elevation and downward rotation of scapula
Innervation: dorsal scapular n. (C5)
Origin/insertion/innervation/action for:
Rhomboid minor m.
Origin: nuchal ligament, C7-T1 spinous processes
Insertion: medial scapula at spine border
Innervation: dorsal scapular n.
Action with rhomboid major m.: elevation, retraction, and downward rotation of scapula
Origin/insertion/innervation/action for:
Rhomboid major m.
Origin: spinous processes T2-5
Insertion: medial scapular border
Innervation: dorsal scapular n.
Action with rhomboid minor m.: elevation, retraction, and downward rotation of scapula
Origin/insertion/innervation/action for:
Teres major m.
Origin: dorsal surface of inferior angle and lower part of lateral border of scapula
Insertion: intertubercular sulcus of humerus
Innervation: subscapularis n.
Action: adduction/medial rotation of humerus
Origin/insertion/innervation/action for:
Supraspinatus m.
Origin: supraspinous fossa
Insertion: superior facet of greater tubercle of humerus
Innervation: supraspinatus n.
Action: assists abduction of arm
Origin/insertion/innervation/action for:
Infraspinatus m.
Origin: infraspinous fossa of scapula
Insertion: middle facet of greater tubercle of humerus
Innervation: supraspinatus n.
Action: lateral rotation of arm
Origin/insertion/innervation/action for:
Teres minor m.
Origin: lateral border of scapula
Insertion: inferior facet of greater tubercle of humerus
Innervation: axillary n.
Action: lateral rotation of arm
Origin/insertion/innervation/action for:
Subscapularis m.
Origin: subscapular fossa
Insertion: lesser tubercle of humerus
Innervation: subscapular n.
Action: medial rotation of arm
The vessels supplying the posterior scapula are primarily from branches arising off what 2 arteries?
Subclavian a.
Axillary a.
These form an anastomosis, allowing COLLATERAL CIRCULATION to the upper limb
What are the 5 anastomosing arterial branches supplying the posterior scapula?
Suprascapular a. Dorsal scapular a. Posterior intercostal aa. Circumflex scapular a. Thoracodorsal a.
The anastomosing arterial branches of the posterior scapula include:
Suprascapular a. Dorsal scapular a Posterior intercostal aa. Circumflex scapular a. Thoracodorsal a.
Which of the above arteries arises from a deep branch of the transverse cervical a. or subclavian a. directly?
Dorsal scapular a.
The anastomosing arterial branches of the posterior scapula include:
Suprascapular a. Dorsal scapular a Posterior intercostal aa. Circumflex scapular a. Thoracodorsal a.
Which of the above arteries is a division of the subscapular a. from the axillary a.?
Thoracodorsal a.
Circumflex scapular a.
The anastomosing arterial branches of the posterior scapula include:
Suprascapular a. Dorsal scapular a Posterior intercostal aa. Circumflex scapular a. Thoracodorsal a.
Which of the above arteries comes from the thoracic aorta?
Posterior intercostal aa.
The anastomosing arterial branches of the posterior scapula include:
Suprascapular a. Dorsal scapular a Posterior intercostal aa. Circumflex scapular a. Thoracodorsal a.
Which of the above arteries comes from the thyrocervical trunk?
Suprascapular a.
In cases of injury, ligation, or occlusion of the axillary a. superior to the ___________ artery, direction of blood flow in that a. is reversed. This allows blood to flow to the distal portion of the axillary a. and the rest of the arm, forearm, and hand.
Subscapular a.
What are 3 named spaces around the teres major m.?
Triangular space
Quadrangular space
Triangular hiatus
What structure(s) occupies the triangular space superolateral to the teres major m.?
Circumflex scapular a.
What structure(s) occupies the quadrangular space superolateral to the teres major m.?
Axillary n.
Posterior humeral circumflex a.
What structure(s) occupies the triangular hiatus lateral to the teres major m.?
Radial n.
Deep brachial a.