Upper Limb Anatomy Flashcards
What is the axilla?
Pyramidal space below the shoulder joint. Provides passageway for vessels and nerves going to and from the upper limb.
What forms anterior wall of axilla?
Pectoralis major and Pectoralis minor muscles.
What forms posterior wall of axilla?
Teres major muscle
Medial wall of axilla?
Thoracic wall and serratus anterior muscle.
Lateral wall of axilla?
Intertubercular groove of the humerus.
What is the axillary artery a continuation of?
subclavian.
Where does the axillary artery begin?
Lateral border of 1st rib.
What does the axillary artery become after it leaves axilla?
Brachial artery. (changes name at lower margin of teres major muscle)
What are the nerve roots of the brachial plexus?
C5, C6, C7, C8 and T1.
What is Erb’s point?
Landmark of brachial plexus on upper trunk. Erb’s palsy.
- Upper trunk of plexus?
2. Lower trunk of plexus?
- C5, C6
2. C8 , T1 (Klumpke’s palsy)
What are the 3 cords of the brachial plexus?
Lateral (C5 and C6)
Posterior (C7)
Medial (C8 and T1)
What are the branches of lateral cord?
Lateral pectoral.
Lateral root of median nerve.
Musculocutaneous nerve.
What are the branches of medial cord?
Medial pectoral. Ulnar nerve. Root of median nerve. Medial cutaneous nerve of arm. Medial cutaneous nerve of forearm.
What are the branches of posterior cord?
Thoracodorsal nerve.
Radial nerve.
Axillary nerve.
Subscapular nerve.
What are the major arterial branches of the upper limb?
Brachial artery.
Ulnar artery.
Radial artery.
What are the main superficial veins of the upper limb?
Cephalic vein
Basilic vein.
Median cubital vein.
Where does the dorsal venous arch lie?
Dorsum of the hand. Dorsal venous plexus.
Where does the 1. Cephalic vein arise and 2. Basiclic vein arise?
- Lateral end of dorsal venous arch.
2. Medial end of dorsal venous arch.
What does the median cubital vein do?
Large communicating vein, shunts blood from cephalic to basilic vein.
What are the dermatomes in the upper limb?
C5-T1. C6 - thumb C7 - index and middle C8 - ring and pinky T1 - arm after pinky leading up.
What is the Glenohumeral joint?
A ball (head of humureus) and socket (glenoid cavity) joint between the scapula and the humerus. It is the major joint connecting the upper limb to the trunk. Rim of cartilage surrounding socket is glenoid labrum.
- What makes up the clavicle?
2. What is the weakest point of clavicle?
- Sternal and acromial ends. Medial and Lateral convexity.
2. Junction between medial 2/3 and lateral 1/3
What makes up the scapula?
Acromion Coracoid process Glenoid cavity Spine of scapula Supraspinous and infraspinous fossa Subscapular fossa Medial and lateral border Inferior and superior angle Supra- and infraglenoid tubercle.
What type of joints are the Acromioclavicular and sternoclavicular?
Synovial plane.
What muscles are responsible for elevation of scapula?
Upper trapezius
Levator scapulae
What muscles are responsible for depression of scapula?
Lower trapezius
pectoralis minor
Muscles causing protraction (forward) of scapula?
Serratus anterior
Pectoralis major
Muscles causing retraction (backward) of scapula?
Trapezius (middle)
Rhomboids
Muscle causing Lateral (upward) rotation: Elevating glenoid cavity?
Upper and middle trapezius
Serratus anterior
Muslces causing medial (downward) rotation: Depressing Gelnoid cavity?
Gravity
Levator scapulae
Rhomboids
Pectoralis minor
Function of glenoid labrum?
Depens glenoid cavity and increases surface of shoulder joints.
What does the caracoacromial ligament do?
Strengthens superior aspect of joint capsule.
What does the coraco-acromial arch do?
Prevents superior displacement of the humeral head.
Which part of the shoulder joint is the weakest?
Inferior part as not protected by muscles and ligaments.
What are Bursae?
Fluid filled interior that provide cushioning around joints.
What is the role of subracromial bursa?
Reduce friction. Supports deltoid and supraspinatus muscles.
What is the most important role of rotator cuff muscles?
Supply mobility and stability of the joint.