Upper Extremity - Sensory Maps

Upper Extremity - Sensory Maps

Upper Extremity Sensory Maps

Upper Arm & Forearm

I. Ulnar nerve

• Covers the medial one third of the hand and the medial-half of the fourth digit and the fifth digit on both the dorsal and palmar sufaces.

II. Radial nerve

• Covers the lateral two-thirds of the dorsal hand and the proximal aspect of the 1st through 3rd and lateral 4th digits.
• Its coverage extends to the lateral proximal palmar thumb.

III. Median nerve

• Completes the dorsal distal finger sensory coverage.
• It covers the bulk of the palmar hand and fingers.
• We square off the ball of the thumb, and show that a special branch of the median nerve (the palmar cutaneous nerve) covers this region.

clinical highlights of the sensory maps of the upper limb

• The palmar cutaneous nerve is selectively spared in carpal tunnel syndrome.
• The medial cutaneous nerves of the forearm and arm cover the medial forearm and arm.
• The intercostobrachial nerve covers the axilla.
• The musculocutaneous nerve covers the lateral forearm.
• The radial nerve covers the lower lateral upper arm.
• The axillary nerve covers the upper lateral arm.
• The supraclavicular nerve covers the shoulder.
• The radial nerve covers the midline forearm and arm.

sensory coverage of the hand

I. Median nerve

• Sensory coverage is from median nerve digital sensory branches.

II. Radial nerve

• Sensory coverage to the hand comes from the superficial sensory radial nerve.

III. Dorsal ulnar sensory coverage

• Comes from the dorsal ulnar cutaneous nerve.

IV. Palmar ulnar sensory coverage

• Divides at the hypothenar eminence into the palmar ulnar cutaneous nerve, proximally, and the superficial sensory division, distally.

Advanced Topics

I. Musculocutaneous nerve

• Covers the lateral forearm via the lateral cutaneous nerve of the forearm.

II. Radial nerve

• Covers the lower lateral upper arm via the lower lateral cutaneous nerve of the arm and the posterior midline forearm and arm via the posterior cutaneous nerves to the forearm and arm.

III. Axillary nerve

• Covers the upper lateral arm via the upper lateral cutaneous nerve of the arm.

IV. Supraclavicular nerve

• Covers the shoulder via specific anatomic branches.

V. Medial cutaneous nerves of the forearm and arm

• Supplied by the medial cord of the brachial plexus and cover the medial forearm and arm.

V. Intercostobrachial nerve

• Supplied by T2 and covers the axilla.