Upper limb lectures Flashcards
Anterior wall of axilla is formed by?
> Pectoralis major muscles
> Pectoralis minor muscle
Posterior wall of axilla is formed by?
Latissimus dorsi muscle
Medial wall of axilla is formed by?
> The thoracic wall
> Serratus anterior muscle
Lateral wall of axilla is formed by?
Intertubercular groove of the humerus
The axillary artery is a continuation of which artery?
Subclavian artery
At which anatomical point does the axillary artery begin?
Outer border of the 1st rib
The axillary artery begins beyond the axilla as which vessel?
The brachial artery
At which anatomical position does the brachial artery begin?
The lower border of the teres major
If there is profuse bleeding of the upper limb what could be done?
Compression of the axillary artery
If there is enlargement of the axillary lymph nodes what does this indicate?
An infection of the upper limb
Or indication of breast cancer in the lateral quadrant of the breast
What is the brachial plexus?
A major network of nerves which innervate the upper limb
Which nerves make up the brachial plexus?
The ventral rami of C5, C6, C7, C8 and T1
Which nerve roots form the upper trunk of the brachial plexus?
C5 and C6
Which nerve roots form the middle trunk of the brachial plexus?
C7
Which nerve roots form the inferior trunk of the brachial plexus?
C8 and T1
What is Erb’s point and what is its clinical significance?
> A landmark of the brachial plexus on the upper trunk.
> Located about 1 inch (2.5 cm) above the clavicle at about the level of the sixth cervical vertebra. The point is the location of an angle between the posterolateral border of the sternocleidomastoid muscle and the clavicle.
> Electrical stimulation at Erb’s point causes contractions of the biceps, deltoid, and other arm muscles.
Nerve network of the upper limb overview?
Roots –> Trunks –> Divisions – > Cords –> Terminal branches
What can cause Erb’s palsy?
Undue seperation (hyper-extension) of the head from the shoulder:
> Anaesthesia
> Fall on shoulder
> Birth injury
How would an individual present with Erb’s Palsy?
“Waiter’s tip appearance”:
> Upper limb medially rotated
> Flexed wrist
Which nerves are affected in Erb’s palsy?
Ventral nerve roots C5, C6:
> Suprascapular nerve
> Musculocutaneous nerve
> Axillary nerv
Which muscle are affected in Erb’s palsy?
Atrophy of :
> Deltoid muscle
> Biceps brachii muscle
> Brachialis muscle
Injury to the lower trunk of the brachial plexus is called?
Klumpke’s palsy
Klumpke’s palsy - Muscles affected?
> Intrinsic muscles of the hand
> Ulnar flexors of the wrist and fingers
Klumpke’s palsy - Cause?
Undue abduction of the arm:
> Hanging injury
Klumpke’s palsy - Clinical presentation?
“claw hand,” in which:
> The forearm is supinated
> The metacarpophalangeal joints are hyperextended
> The fingers are flexed
In the upper limb the Lateral cord is produced from?
1) Superior trunk (C5, C6)
2) Middle trunk (C7)
In the upper limb the posterior cord is produced from?
1) Superior trunk (C5, C6)
2) Middle trunk (C7)
3) Inferior trunk (C8, T1)
In the upper limb the medial cord is produced from?
Inferior trunk (C8, T1)
Major branches of the brachial plexus?
1) Musculocutaneous nerve
2) Axillary nerve
3) Radial nerve
4) Median nerve
5) Ulnar nerve
Action of the musculocutaneous nerve?
The motor fibers innervate:
> Biceps brachii muscle
> Coracobrachialis muscle
> Brachialis muscle
Sensory terminal branch (Lateral cutaneous nerve of the forearm), it innervates the lateral surface of the forearm.
Nerve root source of axillary nerve?
C5, C6
Nerve root source of long thoracic nerve?
C5, C6, C7
Nerve root source of thoracodorsal nerve?
C6, C7, C8
Nerve root source of Subscapular?
C5, C6
Which artery is produced from the subclavian artery?
Axillary artery
Which artery branches from the axillary artery and passes around the distal humerus?
Anterior circumflex humeral artery
Which artery branches from the axillary artery and along the scapular bone?
The sub scapular artery
Which branch of the brachial artery passes behind the humerus?
The profunda brachii artery
Which artery is produced from the axillary artery?
The brachial artery
Which artery is formed by the profunda brachii artery?
Radial recurrent artery