Introduction: This study evaluated the sonoanatomy of the deep motor branch of the ulnar nerve (DBUN) using high-resolution ultrasonography (HRUS). Methods: In 60 wrists of 30 healthy adults, the gross course, cross-sectional area (CSA), and diameter of the DBUN were observed by HRUS (frequency band 3–16 MHz). Its course was assessed by using the distance from anatomical landmarks and depth from the skin. Results: The DBUN was found in all subjects with HRUS, and it branched off from the ulnar nerve before reaching the hamate bone. At the hook-of-hamate level, the mean DBUN CSA was 1.5 ± 0.2 mm2, and the mean diameter was 1.5 ± 0.2 mm. The mean distance from the hamate hook to the DBUN was 5.4 ± 1.0 mm, and the mean depth from the skin was 8.6 ± 1.6 mm. Discussion: Sonoanatomy of the DBUN obtained from HRUS may be useful in detecting or preventing DBUN lesions.
- deep branch of the ulnar nerve
- high-resolution ultrasonography
- nerve injury
ASJC Scopus subject areas
- Clinical Neurology
- Cellular and Molecular Neuroscience
- Physiology (medical)