TCRN Practice Exam 2026 – Complete Prep for Your Test

The ulnar nerve is the most likely to be affected in the scenario of loss of sensation to the fifth finger following an elbow fracture. This nerve runs along the medial aspect of the arm and crosses around the elbow to enter the forearm and hand. Because the ulnar nerve supplies sensation to the medial side of the hand, including the fifth finger, any injury or fracture at the elbow could potentially compromise its function.

When there is trauma to the elbow, particularly in fractures, nerves in the surrounding area can be compressed or damaged. The ulnar nerve is particularly vulnerable due to its location and is commonly involved in such injuries. Loss of sensation specifically in the fifth digit usually indicates ulnar nerve involvement, as the median and radial nerves have different sensory distributions.

This highlights the anatomical pathways of the different nerves in the arm. The radial nerve, for example, primarily innervates the posterior arm and forearm and is responsible for sensation to the back of the hand and not the fifth finger. The axillary nerve is mainly involved with sensation over the skin of the shoulder and supplies the deltoid muscle, while the median nerve primarily affects sensation in the palmar side for the first three and a half fingers but does not extend