Common Digital Nerves in Second, Third and Fourth Webs Exam
- In patient's with lacerations, sensation is assessed by examining light touch and/or two point discrimination.
- The digital nerves are branches of the common digital nerves which originate from the median and ulnar nerves.
- The digital nerves supply sensation to the skin via the free nerve endings, the Pacinian corpuscles, and the Meissner’s corpuscles.
Diagrams & Photos
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Testing light touch distal to a laceration. Note patient's eyes are closed. -
Testing two point discrimination distal to a laceration. -
Anterior (palmar or volar) Sensation by Nerve: 1 = median nerve; 2 = dorsal radial sensory nerve; 3 = ulnar nerve; 4 = lateral antebrachial cutaneous nerve; 5 = medial antebrachial cutaneous nerve; 6 = radial dorsal antebrachial cutaneous nerve; 7 = medial brachial cutaneous nerve; 8 = intercostobrachial nerve; 9 = axillary nerve (superior lateral brachial cutaneous nerve. -
Motor, sensory and triceps reflex exam for C6 Root -
Motor, sensory and reflex exam for C7 Root. -
Motor, sensory and reflex exam for C8 Root. -
Note severe anhydrous of skin due to denervation of the sweat glands.
Key Points
- The digital nerves lie palmar (superficial) to the arteries in the finger and dorsal (deep) to the common digital arteries in the palm.
- The common digital nerves are dorsal to the superficial intermetacarpal ligaments (Skoog's ligaments).