Median Nerve Injury in US-guided Carpal Tunnel Injections

Carpal tunnel syndrome (CTS) is the most common nerve compression disorder in the upper extremity. It can be treated with surgical or nonsurgical methods. When nonsurgical treatment is indicated, local corticosteroid injection into the carpal tunnel can be used to reduce pain and tingling sensation. Currently, the most widely used ultrasound (US)-guided CTS-injection method are transverse and longitudinal approach. Although we can accurately place needle within the carpal tunnel using this approach and this approach is easy to learn, median nerve injury (MNI) is still an inevitable complication and difficult to be treat. MNI is the most serious complication associated with a local corticosteroid injection for CTS among them. A MNI will be presented with shooting pain at the injection time or transient exacerbation of CTS symptoms following the corticosteroid injection because of the pain which often masked by anesthetic during injection. Permanent damage of MN should be considered if the symptoms persist and exacerbate for more than 48 hours. A surgical intervention such as neurolysis, resection or graft repair or a gentle debridement of the crystal from the nerve may be performed in the patients with median nerve damage. Hence, early recognition of MNI before corticosteroid injection may avoid the permanent damage of MN. Accordingly, the aim of this study is to determine the relationship between the MNI with the possible influencing factors and findings in the US-guided corticosteroid injection for patients with CTS with and to compare the therapeutic efficacy in the patients with and without MNI.