Diagnostic accuracy of nerve conduction studies versus ultrasonography in early diagnosis of ulnar nerve entrapment at the elbow

Background Ulnar nerve entrapment at the elbow (UNE) is a compression of the ulnar nerve at the elbow level that is mainly diagnosed clinically and confirmed by electrodiagnostic testing as well as diagnostic imaging of the ulnar nerve. Objectives To evaluate the diagnostic accuracy of nerve conduction studies (NCSs) versus ultrasonography (US) in the early diagnosis of UNE. Patients and methods This cross-sectional study included 160 patients: 80 patients with symptoms suggestive of UNE for less than or equal to 6 weeks and a control group of 80 healthy adults. Both groups were clinically examined and assessed using a self-administered questionnaire of UNE. Furthermore, motor and sensory NCS and short-segment nerve conductions of ulnar nerve in both groups with measurement of ulnar nerve cross-sectional area using US in the case group were performed. Results A high sensitivity of using NCSs for early diagnosis of UNE measuring conduction velocity and amplitude was exhibited via traditional 10-cm NCSs (95 and 82.5%, respectively) and short-segment nerve conductions (97.5 and 90%, respectively). US has showed a decrease in the sensitivity (40%) in comparison with short-segment amplitude drop, with an accuracy of 91% as well as a specificity of 99%, and there was a high sensitivity of short-segment amplitude drop D2/ME (80%) when compared with US at P2, which exhibited an accuracy of 91% and specificity of 92%. Conclusion Herein, electrodiagnostic in addition to the US studies would play a vital role in increasing the accuracy of diagnosis of UNE; additionally, it will help in precise localization of the site of pathology.