Objective: The aim of this study is to elucidate the significance of electroph ysiological data of the palmar cutaneous branch of the median nerve (PCBm) in th e diagnosis entrapment of the PCBm concomitant with carpa...Objective: The aim of this study is to elucidate the significance of electroph ysiological data of the palmar cutaneous branch of the median nerve (PCBm) in th e diagnosis entrapment of the PCBm concomitant with carpal tunnel syndrome (CTS) . Materials and Methods: Clinical and electrophysiological studies were conducte d for abnormal sensation of the thenar eminence in eight CTS patients. Sensory n erve action potentials (SNAPs) of the PCBm were recorded from bipolar surface el ectrodes over the forearm using an orthodromic method. The preoperative SNAP eva luation was compared with the operative findings. Results: The eight patients we re divided into two groups based on the characteristics of SNAPs of the PCBm; fi ve patients had normal SNAPs of the PCBm and three patients had delayed or absen t SNAPs. Open surgery confirmed entrapment of the PCBm in one patient in the fir st group and all patients in the latter group. Conclusions: Although clinical sy mptoms were not always reliable to diagnose entrapment of the PCBm in CTS, elect rophysiological study of the PCBm was highly sensitive (75%) and entirely speci fic (100%) to demonstrate the entrapment of the PCBm preoperatively.展开更多
文摘Objective: The aim of this study is to elucidate the significance of electroph ysiological data of the palmar cutaneous branch of the median nerve (PCBm) in th e diagnosis entrapment of the PCBm concomitant with carpal tunnel syndrome (CTS) . Materials and Methods: Clinical and electrophysiological studies were conducte d for abnormal sensation of the thenar eminence in eight CTS patients. Sensory n erve action potentials (SNAPs) of the PCBm were recorded from bipolar surface el ectrodes over the forearm using an orthodromic method. The preoperative SNAP eva luation was compared with the operative findings. Results: The eight patients we re divided into two groups based on the characteristics of SNAPs of the PCBm; fi ve patients had normal SNAPs of the PCBm and three patients had delayed or absen t SNAPs. Open surgery confirmed entrapment of the PCBm in one patient in the fir st group and all patients in the latter group. Conclusions: Although clinical sy mptoms were not always reliable to diagnose entrapment of the PCBm in CTS, elect rophysiological study of the PCBm was highly sensitive (75%) and entirely speci fic (100%) to demonstrate the entrapment of the PCBm preoperatively.