Electrophysiological Assessment for Splinting in the Treatment of Carpal Tunnel Syndrome

An electrophysiological study is commonly used to decide a therapeutic strategy for carpal tunnel syndrome (CTS). In this study, the electrophysiological parameter measurement as a prognostic indicator for CTS after wrist splinting was assessed to identify appropriate candidates for wrist splinting for CTS. One hundred and six hands in 78 patients with CTS were treated by wrist splinting, and three electrophysiological parameters; median distal motor latency (DML) of the abductor pollicis brevis (APB) muscle, median distal sensory latency (DSL) of the index finger, and second lumbrical-interossei latency difference (2L-INT LD); were statistically analyzed to compare with clinical results by Kelly's evaluation respectively. Clinical results were excellent in 15 hands, good in 51 hands, fair in 19 hands, and poor in 21 hands. The recordable rate in 2L-INT LD (99.1%) was higher than DML (96.2%) and DSL (79.2%). Patients with DML less than 6.5 ms, DSL less than 5.7 ms, or 2L-INT LD less than 2.5 ms had significantly excellent or good clinical results. The odds ratios of the DML, DSL, and the 2L-INT LD were 7.93, 8.81, and 12.8, respectively. This study demonstrated that CTS patients with DML less than 6.5 ms, DSL less than 5.7 ms, or 2L-INT less than 2.5 ms were good candidates for wrist splinting. Especially, the 2L-INT LD could be the most reliable indicator to predict clinical results for all grades of CTS. This electrophysiological information could be useful in further improvement of accurate diagnosis of CTS, and may help in the assessment of appropriate treatment for CTS with wrist splinting.