The brachial plexus innervates the entire upper limb – except part of the skin of the upper half of the medial arm which is innervated by the intercostobrachial nerve

The intercostobrachial nerve is synonymous to the lateral cutaneous branch of the second intercostal nerve

The intercostobrachial nerve joins the medial cutaneous nerve of the arm to supply the skin of the upper half of the medial arm

Repositioning of the needle tip is oftentimes necessary in order to cover all three cords around the axillary artery from two o’clock to ten o’clock

Care should be taken not to pierce the axillary vein

Click on the VIDEO CLIP button to view the video

In the video: Notice that local anaesthetic is injected on the wrong side of the clavipectoral fascia which has to be penetrated by the needle before local anaesthetic spreads appropriately around the medial cord

In the infraclavicular block the local anaesthetic should be injected periarterially in the seven o’clock position (seeing the axillary artery as a clock face)

However, it is often necessary to reposition the needle tip in order to inject local anaesthetic periarterially from the two o’clock position around the artery to the ten o’clock position

Click on the VIDEO CLIP button to view the video

The infraclavicular brachial plexus block provides cutaneous anaesthesia of the entire upper limb

The radial nerve innervates the skin of the back of the brachium and the lateral hand

The musculocutaneous nerve innervates the skin of the lateral antebrachium

The ulnar nerve innervates the skin of the medial hand and fingers

The median nerve innervates the skin of the anterior part of the lateral hand and fingers and the distal dorsal part of the second and third finger

The skin of the medial arm and forearm is innervated by the medial cutaneous nerves of the arm and forearm. They are both derived from the medial cord of the brachial plexus and covered by the infraclavicular brachial plexus block

The radial nerve innervates the skin on the extensor side of the upper limb

The median nerve only innervates the skin on the hand

The infraclavicular brachial plexus block covers all muscles of the upper limb distal to the shoulder:

The radial nerve innervates
– the elbow extensor muscles
– the wrist extensor muscles

The musculocutaneous nerve innervates the elbow flexor muscles

The ulnar nerve innervates the intrinsic muscles of the hand including the medial finger flexors

The median nerve innervates the wrist flexor muscles including the lateral finger flexors

The cutaneous distribution of the ulnar nerve is only to the hand

The infraclavicular block anaesthetizes the brachial plexus inside the axilla

The brachial plexus in the infraclavicular region consists of three cords (syn: fascicles): the lateral, the posterior, and the medial cord

They run in close relationship to the axillary artery

That is exploited for the purpose of the infraclavicular brachial plexus block

The infraclavicular brachial plexus block anaesthetize all the bones and joints of the upper limb distal to the shoulder:

– The axillary nerve innervates the head of the humerus

– The radial nerve innervates the arm, the elbow, the forearm, the hand and the
radial fingers

– The musculocutaneous nerve innervates the humerus

– The ulnar nerve innervates the elbow and the hand and the ulnar fingers

– The median nerve innervates the elbow and the forearm and the hand and the
radial fingers