Cutaneous nerves of upper limb

Cutaneous nerves of upper limb

❖ Supraclavicular nerves ( C3, C4 ) : Origin - Cervical plexus ✓ Supplies skin over clavicle and superolateral aspect of pectoralis major

❖ Superior lateral cutaneous nerve of arm ( C5, C6 ) : Origin - axillary nerve ✓ Supplies skin over lower part of the deltoid and on lateral side of mid arm

❖ Inferior lateral cutaneous nerve of arm ( C5, C6 ) : Origin - Radial nerve ✓ supply skin over inferolateral aspect of arm

❖ Posterior cutaneous nerve of arm ( C5, C6 ) : Origin - Radial nerve ✓ supplies skin on posterior arm as far as olecranon

❖ Posterior cutaneous nerve of forearm ( C5, C8 ) : Origin - Radial nerve ✓ supplies posterior forearm to wrist

❖ Lateral cutaneous nerve of forearm ( C6, C7 ) : Origin - Musculocutaneous nerve ✓ Supplies skin of anterolateral forearm to wrist

❖ Medial cutaneous nerve of the forearm ( C8, T1 ) : Origin - Medial cord of brachial plexus ✓ supplies skin of anteromedial aspect to wrist

❖ Medial cutaneous nerve of arm ( C8, T2 ) : Origin - Medial cord of brachial plexus ✓ Supplies skin of medial aspect of distal arm

❖ Intercostobrachial nerve ( T2 ) : Origin - Second intercostal nerve ✓ Supplies skin of axilla and medial aspect of proximal arm
Important points to remember
❖ ‘lift off’ test : To check medial rotation at shoulder joint done by subscapularis muscle. ❖ Belly press’ test : Is to check the integrity of subscapularis muscle.

Arterial Supply of Upper Limb

❖ Subclavian artery ✓ Right subclavian artery (RSA) is one of the terminal branches of the brachiocephalic artery ✓ Left subclavian artery (LSA) arises as the third branch of the aortic arch after the left common carotid artery • It is divided into three parts in relation to scalenus anterior: ➢ Branches - Mnemonic: VIT C, D (as in vitamins C and D). ❖ first part ✓ vertebral artery: supply the posterior cerebral circulation ✓ internal thoracic artery: will study in thorax ✓ thyrocervical trunk: very short trunk that soon divides into 4 branches 1. The inferior thyroid artery 2. The suprascapular artery 3. The ascending cervical artery 4. The transverse cervical artery ( cervicodorsal trunk ) • The superficial cervical artery • The dorsal scapular artery ❖ second part ✓ Costocervical trunk: two branches 1. superior (supreme) intercostal artery : supplies the first two intercostal spaces 2. deep cervical artery : supplies the posterior deep cervical muscles and may anastomose with the occipital artery

✓ Dorsal scapular artery: courses posteriorly; some authors describe this branch as arising from the thyrocervical trunk ❖ third part ✓ nil