Upper Limb Session 1 and 2 Flashcards
What are the functions of the axilla?
The pyramidal space below the shoulder joint. It provides passageway for vessels and nerves going to and from the upper limb
Outline the anterior wall of the axilla
Formed by Pec. Major and Minor
Outline the posterior wall of the axilla
Scapularis, teres minor and lat. dorsi
Outline the medial wall of the axilla
Thoracic wall and serrates anterior muscles
Outline the lateral wall of the axilla
Intertubercular sulcus of the humerus
Where does the axillary artery originate?
Subclavian artery at the upper margin of the first rib
What does the axillary artery continue as and where does it end?
Continues as the brachial artery beyond the lower border of the teres major muscle
What is the brachial plexus?
A major network of nerves innervating the upper limb
Where does the brachial plexus begin?
Cervical region and extends into the axilla
What forms the brachial plexus?
Ventral rami of C5, C6, C7, C8, T1
Outline the division of the brachial plexus
Roots, trunks, divisions, cords and branches
Read That Damn Cadaver Book
Roots, trunks, divisions, cords and branches
Describe Erb’s Point
Site of the superior trunk
Located about 2-3cm above the clavicle
Describe what happens when Erb’s point is injured?
Erb’s Palsy - characteristic waiters tip where shoulder is internally rotated and wrist is flexed
What is the common aetiology of Erb’s Palsy?
Undue separation (hyperextension) of the head from the shoulder - often from birth, falling on shoulder or anaesthesia
What nerve roots form the lower trunk?
C8 and T1
What does injury to the lower trunk cause?
Klumpke’s palsy
Describe Klumpke’s palsy
Intrinsic muscle of the hand are affected and ulnar flexors of the wrist and fingers
What is the common aetiology go Klumpke’s palsy?
Undue abdurction of the arm
How are the three cords of the brachial plexus named?
According to their relation to the axillary artery
What are the main branches of the lateral cord?
Lateral pectoral nerve
Lateral root of median nerve
Musculocutaneous nerve
What are the main branches of the medial cord?
Medial pectoral nerve Median nerve Ulnar nerve Medial cut. nerve of the arm Medial cut. nerve of the forearm
What are the main branches of the posterior cord?
Thoracodorsal nerve
Axillary nerve
Radial nerve
Subscapular nerve
In the upper arm the brachial artery immediately gives rise to what other artery?
Profunda brachii
Where does the profound brachii arise?
Just distal to the margin of the teres major
Where does the profound brachii travel?
Within the radial groove of the humerus
What other structures accompany the profound brachii in the radial groove?
Radial nerve
What does the profound brachii supply?
Structures on the posterior aspect of the arm (principally the triceps muscle)
How does the profounda brachii terminate?
In an anastomosing network of vessels at the elbow joint
The brachial artery descends down the arm immediately posterior to what?
the median nerve
As the brachial a. crosses the cubital fossa it passes under what muscle?
Brachialis
How does the brachial artery terminate?
Bifurcatin into the radial and ulnar arteries
What vein arises from the dorsal venous plexus of the hand on the medial side?
The basilic vein
What happens to the basilic vein at the border of the teres major?
The vein moves deep and coalesces with cephalic vein to form the axillary vein
What vein arises from the dorsal venous plexus of the hand on the anterolateral side?
Cephalic
Outline the course of the cephalic vein
Moves through the deltoid groove between the deltoid and pec. major muscles to join the axillary vein
What is the large communicating vein that shunts blood from the basilic to the cephalic?
Median cubital vein
Axillary lymph nodes are divided into 5-6 distinct groups; name them.
Lateral/axillary nodes Apical/supraclavicular nodes Central nodes Interpectoral nodes Anterior mammary nodes Posterior/subscapular nodes
What is the pectoral girdle?
A set of bones which connect the upper limb to the axial skeleton on each side
What joint does the upper limb and the shoulder articulate at?
Glenohumeral joint
How do you determine the sternal end of the clavicle?
Large facet
Oval shaped impression on inferior surface (attachement for the costoclavicular ligament)
How do you determine the acromial end of the clavicle?
Small facet for articulation with the acromial processs of the scapula
Coronoid tubercle - insertion for the coronoid ligament (medial part of the CC ligament)
How is the clavicle divided up?
Thirds (middle third being most susceptible to fracture)
What type of joint is the AC and SC joints?
AC - planar synovial
SC - synovial saddle
What is the function of the subscapular fossa?
Attachment for the subscapularis (rotator cuff)
What is the function of the coracoid process?
Attchement for the short head of the biceps brachii, coracobrachialis and pec. minor