Related Experiment Video
Updated: Jul 5, 2026

Screening of Axonal Degeneration in Carpal Tunnel Syndrome Using Ultrasonography and Nerve Conduction Studies
Published on: January 11, 2019
Ulnar nerve and cubital tunnel ultrasound in ulnar neuropathy at the elbow
Joon Shik Yoon1, Suk-Joo Hong, Byung-Jo Kim
1Department of Physical and Rehabilitation Medicine, Korea University Guro Hospital, Korea University College of Medicine, Seoul, Korea.
Objective:
To determine the accuracy of the ultrasonographic measurement of ulnar nerve to cubital tunnel area for diagnosis of ulnar neuropathy at the elbow.
Design:
Patients with confirmed ulnar neuropathy at the elbow and normative, healthy volunteers were evaluated with high-resolution ultrasound. The cross-sectional areas (CSAs) of the ulnar nerve and cubital tunnel were measured with the elbow extended and flexed, and results from the 2 groups were compared.
Setting:
Electromyography laboratory and radiology department of a tertiary care center.
Participants:
Twenty-seven patients with ulnar neuropathy at the elbow and 20 controls.
Interventions:
Not applicable.
Main Outcome Measure:
The ratio of ulnar nerve to cubital tunnel CSA with the elbow flexed.
Results:
The ulnar nerve, with the elbow flexed, was larger in those with ulnar neuropathy at the elbow, and this group also had larger cubital tunnels than did controls. In those with ulnar neuropathy at the elbow, the ratio of the ulnar nerve to cubital tunnel was .31, and in the controls it was .32, which was not significantly different (P=.89).
Conclusions:
The ratio of ulnar nerve to cubital tunnel did not differentiate those with ulnar neuropathy at the elbow from controls.
Related Concept Videos
Bones of the Upper Limb: Ulna
Spinal Nerves: Plexus I
The Cervical Plexus
The cervical plexus, formed by the anterior rami of the first four...
Arteries of the Upper Limbs
Bones of the Upper Limb: Radius
The radius has a nail-shaped head, and a short...
Bones of the Upper Limb: Humerus
Muscles that Move the Forearm
Forearm Flexors
The biceps brachii, brachialis, and brachioradialis are forearm flexors. The biceps brachii is made up of two heads. Its long head originates at the supraglenoid tubercle of the scapula, whereas that of the short head is...