Preliminary Prospective Preoperative and Postoperative Evaluation of Median Nerve Stiffness by Using Sonoelastography

Carpal tunnel syndrome is the most common peripheral nerve entrapment syndrome. No previous studies have compared preoperative and follow-up sonoelastography results or investigated the correlation of median nerve stiffness with the subjective/objective outcomes. Therefore, the aim of this study was to compare the preoperative and postoperative elastography after carpal tunnel release and find the correlation with associated subjective/objective outcomes.From May 2017 to March 2020, 32 patients (6 males, 26 females; 34 hands) with carpal tunnel syndrome were enrolled in this prospective study. Demographic data, QuickDASH score (Chinese version), Boston Carpal Tunnel Questionnaire (Chinese version), nerve conduction velocity/electromyography, and median nerve stiffness by sonoelastography were recorded.Comparisons of preoperative and average sonoelastography findings 1.5 years postoperatively showed a significant decrease in stiffness presented by velocity (Vs) (preoperative Vs, 4.63 ± 1.27 m/s, vs postoperative Vs, 3.39 ± 0.59 m/s; P < 0.001). Changes in subjective functional outcomes also showed the same significant trend. Based on the neurophysiologic study, the improvement of nerve conduction study and elastography have the significant correlation.The same trend of preoperative and postoperative changes in median nerve stiffness and subjective questionnaires/objective neurophysiologic studies may imply that sonoelastography can be used to assess the response to surgery in patients with carpal tunnel syndrome.