Ulnar Nerve Blocks


- Discussion:
    - ulnar nerve blocks are used for frxs of little finger ray & in along w/ median and radial sensory blocks for ring finger ray fractures;

- Anatomy:
    - ulnar nerve has two sensory branches that provide sensory innervation to ulnar side of the hand;
         - palmar branch
               - found radial to FCU tendon at proximal crease;
         - dorsal branch
               - divides from palmar branch approx 4-5 cm proximal from wrist;
               - courses under FCU  tendon to dorsal ulnar side of the hand;
    - ulnar nerve block at at elbow where nerve courses 0.5 cm below the skin between the medial epicondyle & olecranon;
          - ulnar nerve is palpated between medial epicondyle & olecranon;
          - inject 2-3 ml of anesthetic on either side of nerve but not directly into it;
          - paresthesias indicate proximity, and therefore, the needle has to be moved slightly away from the nerve before injection;
    - ulnar block nerve at wrist:
          - ulnar nerve lies just under FCU tendon proximal to the wrist crease;
          - aspiration is necessary prior to injection, as ulnar artery  runs adjacent to the nerve;
                 - note that the ulnar artery lies superficial (volar) and radial to the ulnar nerve;
          - to block dorsal sensory branch of ulnar nerve, the needle is passed subQ & directed dorsally toward the base of the fifth metacarpal



Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Thursday, December 8, 2011 3:55 pm