Ann Rehabil Med.  2021 Aug;45(4):325-330. 10.5535/arm.21101.

Is Palmar Cutaneous Branch of the Median Nerve More Swollen in Carpal Tunnel Syndrome?

• Jeong HM
• Jeong YH
• Yoon JS

• KMID: 2519639
• DOI: http://doi.org/10.5535/arm.21101

Abstract

Objective
To investigate the characteristics of the palmar cutaneous branch of the median nerve (PCBMN) in patient with carpal tunnel syndrome (CTS) using high-resolution ultrasound.
Methods
Fourteen healthy volunteers (17 wrists) and 31 patients with CTS (41 wrists) were evaluated by high-resolution ultrasound. All patients were classified into three groups based on the electrophysiologic CTS impairment severity: mild, moderate, and severe. Using high-resolution ultrasound, the cross-sectional areas (CSAs) of the PCBMN were measured at the proximal wrist crease, bistyloid line, and distal wrist crease, and the largest CSA was defined as the maximal CSA.
Results
The maximal CSA of the PCBMN of the control, mild, moderate, and severe CTS groups were 0.27±0.08, 0.30±0.07, 0.35±0.10, and 0.47±0.13 mm², respectively. The maximal CSA of the PCBMN was significantly larger in the severe CTS group than in the other groups.
Conclusion
The PCBMN could be concomitantly affected in patients with severe CTS.

Keyword

Palmar cutaneous branch, Median nerve, Carpal tunnel syndrome, Ultrasonography

Figure

• 

  Fig. 1. Scans of the palmar cutaneous branch of the median nerve at three different levels (A, B, C) of the wrist. MN, median nerve; FCR, flexor carpi radialis; PL, palmaris longus; FPL, flexor pollicis longus; FDS, flexor digitorum superficialis.

• 

  Fig. 2. Comparisons of the maximal cross-sectional areas (CSAs). (A) Control group versus carpal tunnel syndrome (CTS) group. (B) Between control, mild, moderate, and severe CTS groups. *p<0.05.

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