Korean J Clin Neurophysiol.  2014 Jun;16(1):21-26. 10.14253/kjcn.2014.16.1.21.

Clinical and Electrophysiological Changes after Open Carpal Tunnel Release: Preliminary Study of 25 Hands

• Yang JW
• Sung YH
• Park KH
• Lee YB
• Shin DJ
• Park HM

• KMID: 1708887
• DOI: http://doi.org/10.14253/kjcn.2014.16.1.21

Abstract

BACKGROUND
Electrophysiological study has been known as a useful method to evaluate the therapeutic effect of operation in idiopathic carpal tunnel syndrome (CTS). The purpose of this study was to evaluate the clinical and electrophysiological changes after carpal tunnel release (CTR) compared to the preoperative results.
METHODS
We analyzed the changes of nerve conduction study (NCS) before and after minimal open carpal tunnel release in 18 patients (25 hands) with CTS. Follow-up study was performed over 6 months after operation.
RESULTS
Clinical improvement was seen in all cases after CTR. In contrast, electrophysiological improvement was various depending on the parameters; the mean median sensory latency and nerve conduction velocity (NCV) improved significantly (p = 0.001). The mean median motor latency also improved, but NCV and compound muscle action potential (CMAP) amplitude did not change. The extent of improvement was evident in moderate CTS, but not in severe CTS.
CONCLUSIONS
In this preliminary study, all subjects who underwent CTR achieved a clinical relief along with a significant improvement of electrophysiological parameters such as median sensory latency, sensory NCV and median distal motor latency. After CTR, a number of cases with mild to moderate CTS showed a prominent improvement of clinical and electrophysiological parameters, while fewer improvements were seen in severe CTS, although it did not reach the statistical significance.

Keyword

Carpal tunnel syndrome; Electrophysiology; Median nerve

MeSH Terms

Action Potentials
Carpal Tunnel Syndrome
Electrophysiology
Follow-Up Studies
Hand*
Humans
Median Nerve
Neural Conduction

Figure

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  Figure 1. Pre- and post-operative electrophysiological changes in median sensory nerve. A significant improvement was seen in SNCV over F-W segment (A) and over P-W segment (B).

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  Figure 2. Pre- and post-operative electrophysiological changes in median motor nerve. A significant improvement was seen in DML. SNCV; sensory nerve conduction velocity, F-W; finger-wrist, P-W; palm-wrist, DML; distal motor latency.

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