Ulnar Nerve in Guyon's Canal
- In patients with lacerations, sensation is assessed by examining light touch and/or two point discrimination.
- The ulnar nerve provides sensation palmarly to the little finger and ulnar half of the ring finger.
- The ulnar nerve also supplies the dorsal sensation around the fingernail and dorsal DIP joint of the ring and little fingers. This sensation is supplied by the dorsal branches of the digital nerves which originates from the ulnar nerve.
Diagrams & Photos
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Ulnar nerve with its sensory and motor branches. -
Assessing palmar ulnar nerve sensation by examining light touch in volar tip of the little finger. -
Assessing dorsal ulnar nerve sensation of ulnar dorsal hand and little finger by examining light touch.
Key Points
- The ulnar nerve also provides sensation to the dorsal ulnar hand, little finger, and ulnar half of the dorsal ring finger.
- The ulnar nerve also provides motor innervation to the ulnar innervated intrinsic muscles which include the hypothenar muscles, the dorsal and volar interosseous muscles, the ulnar two lumbrical muscles, the adductor pollicis, and the deep head of the flexor pollicis brevis are all innervated by the ulnar nerve.