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Updated: Feb 10, 2026

Metacarpal Small Incision for Carpal Tunnel Syndrome
Published on: April 5, 2024
Sonographic median nerve change after steroid injection for carpal tunnel syndrome
Jia-Chi Wang1,2, Kon-Ping Lin3,4, Kwong-Kum Liao3,4
1Department of Physical Medicine and Rehabilitation, Taipei Veterans General Hospital, No. 201, Section 2, Shih-Pai Road, Beitou District, Taipei City, 11217, Taiwan.
Introduction:
The sonographic changes of the median nerve after steroid injection for carpal tunnel syndrome (CTS) still require investigation.
Methods:
Sixty-two patients with CTS were included. The Boston Carpal Tunnel Questionnaire was administered, and ultrasonographic examinations were performed before and at 2, 6, and 12 weeks after steroid injection. At 12 weeks, general improvement was scored on a 6-point Likert scale.
Results:
After treatment, the cross-sectional area (CSA) of the median nerve was significantly reduced at 2-, 6-, and 12-week follow-ups (for each, P < 0.001, analysis of variance). The "significant improvement" group (n = 39) had a significantly greater reduction in the CSA at the carpal tunnel inlet (P = 0.014) and CSA in the proximal carpal tunnel (P = 0.003) compared with the "little/no improvement" group (n = 23).
Discussion:
Sonographic measurement of CSA may be considered complementary to the standard clinical evaluation in monitoring of treatment response in patients with CTS. Muscle Nerve 58: 402-406, 2018.
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