Effectiveness of steroid injection in treating patients with moderate and severe degree of carpal tunnel syndrome measured by clinical and electrodiagnostic assessment.

OBJECTIVES: This study is to assess the effectiveness of steroid injections to improve the clinical and electrodiagnostic (EDX) parameters associated with moderate and severe carpal tunnel syndrome (CTS). The study will also evaluate the correlation between EDX and clinical assessment scores.
METHODS: Patients with moderate or severe CTS identified by EDX were recruited. A visual analog scale, the Boston Carpal Tunnel Syndrome Questionnaire, and EDX procedures were all used during patients' pretreatment. These tests were repeated at 4 and 8 weeks after patients received a 20 mg injection of triamcinolone in the carpal tunnel to evaluate the changes and the correlation between the clinical and EDX parameters.
RESULTS: Although moderate and severe CTS showed significant improvement in clinical parameters at 4 weeks and 2 months, EDX parameters of moderate CTS were significantly improved at 4 weeks, but diminished at 8 weeks. Those with severe CTS were not significantly improved at either 4 or 8 weeks. There was no correlation between clinical and EDX results for both groups. DISCUSSION: Steroid injection is an effective method to improve clinical scales but has limited ability to restore nerve conduction in moderate or severe CTS. Because there is no correlation between clinical and EDX parameters, we should consider both clinical and neurophysiologic tests to assess CTS.