Post-Operative Assessment of Ulnar Nerve Tension Using Shear-Wave Elastography

Background: Ulnar nerve compression at the elbow level is the second-most common entrapment neuropathy. The aim of this study was to use shear-wave elastography for the quantification of ulnar nerve elasticity in patients after ulnar nerve decompression with anterior transposition and in the contralateral non-operative side. Method: Eleven patients with confirmed diagnosis and ulnar nerve decompression with anterior transposition were included and examinations were performed on an Aixplorer(TM) ultrasound system (Supersonic Imagine, Aix-en-Provence, France). Results: We observed significant differences at 0-degree (p < 0.001), 45-degree (p < 0.05), 90-degree (p < 0.01) and 120-degree (p < 0.001) elbow flexion in the shear elastic modulus of the ulnar nerve in the operative and non-operative sides. There were no statistically significant differences between the elasticity values of the ulnar nerve after transposition at 0-degree elbow flexion and in the non-operative side at 120-degree elbow flexion (p = 0.39), or in the ulnar nerve after transposition at 120-degree elbow flexion and in the non-operative side at 0-degree elbow flexion (p = 0.09). Conclusion: Shear-wave elastography has the potential to be used postoperatively as a method for assessing nerve tension noninvasively by the estimation of mechanical properties, such as the shear elastic modulus.