Ultrasonograhic Identification of the Entrapment of a Transligamentous Sensory Branch of the Ulnar Nerve.
Journal
Diagnostics (Basel, Switzerland)
Journal Volume
16
Journal Issue
3
Start Page
405
ISSN
2075-4418
Date Issued
2026-01-27
Author(s)
Abstract
Anatomical variations of the ulnar nerve at the wrist are uncommon and may lead to diagnostic confusion or iatrogenic injury if unrecognized. We present an ultrasound-based identification of a rare transligamentous ulnar nerve sensory branch entrapment in an elderly male with chronic ulnar-sided hand paresthesia. High-resolution ultrasonography revealed an aberrant sensory branch deviating from the ulnar nerve, piercing the palmar carpal ligament, and coursing superficially rather than entering Guyon's canal. Further assessment demonstrated focal nerve flattening within the ligament with proximal enlargement, consistent with entrapment. This case highlights the value of ultrasound in detecting rare peripheral nerve variants and their entrapments. Therefore, it is also noteworthy to extend the sonographic evaluation beyond conventional entrapment sites at the wrist.
Subjects
aberrant nerve
ligament
paresthesia
ultrasound
wrist
Type
journal article