J Korean Orthop Assoc.  2013 Aug;48(4):290-296.

Relationship between Change of Median Nerve Cross-Sectional Area Measured by Ultrasonography and Prognosis after Carpal Tunnel Release

• Lee SJ
• Kim JS
• Choi YR
• Kim SJ
• Kang HJ

Abstract

PURPOSE
The purpose of this study was to evaluate cross-sectional area of the median nerve using ultrasound in patients with carpal tunnel syndrome before and after endoscopic intervention, and to verify the level at which it can be used in prediction of outcome.
MATERIALS AND METHODS
A prospective study was conducted in 21 patients who underwent endoscopic carpal tunnel release from March 2011 to March 2012. Median nerve cross-sectional area was measured before the operation and three months after the operation at the level of lunate, pisiform and hamate. The Boston questionnaire was evaluated before the operation and three months after the operation, and then allocated as two groups (group I: symptom improvement of more than 25%, group II: symptom improvement less than 25%). Then, differences of cross-sectional area between preoperative measurement and postoperative measurement on three levels were compared between the two groups.
RESULTS
Nineteen patients were females and two were males ranging in age between 35-79 years (mean, 55.4 years). Significant differences were observed between the two groups at the lunate level. However, at the level of pisiform and hamate, no differences were observed between the two groups.
CONCLUSION
Measurement of median nerve cross-sectional area at the lunate level showed significant correlation with outcome of carpal tunnel release.

Keyword

carpal tunnel release; cross-sectional area; outcome; ultrasonography

MeSH Terms

Boston
Carpal Tunnel Syndrome
Female
Humans
Male
Median Nerve
Prognosis
Prospective Studies
Surveys and Questionnaires

Figure

• 

  Figure 1 Ultrasonographic measurement of median nerve (white arrow, circle) cross-sectional area at three different levels. (A) Lunate (L) level, (B) pisiform (P) level, (C) hamate (H) level.

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