Peripheral nerve blocks may be preferred to digital blocks because the injection itself is less painful and it does not distort the tissue at the site of injury . An ulnar nerve block can be utilized for analgesia during procedures in the ulnar sensory distribution such as Boxer’s fracture, 5th phalangeal fractures, and medial hand lacerations .
See Figures 3 & 4 or check out this Trick of the Trade for more information on performing an ulnar nerve block.
Pearl: Ultrasound-guided blocks have the added benefit of directly visualizing the neurovascular bundle to avoid intravascular injection as well as increasing the success of anesthesia .
Figure 3: Ultrasound images. Left image: The ulnar nerve (N) is seen in the short-axis immediately adjacent to the ulnar artery (A) in the volar aspect of the mid-forearm. Right image: The nerve is followed proximally until the nerve (N) and artery (A) separate. Author’s own images.
Figure 4: Ultrasound images. Left image: The needle (arrow) is seen entering from the left side of the screen, in-plane to the ultrasound transducer. Right image: Infiltration of lidocaine (L) to bathe the ulnar nerve (N). Author’s own images.