Reliability of Upper Limb Neurodynamic Tests: Median, Radial and Ulnar Nerves

Objective: in the evaluation of peripheral nerves, upper limb neurodynamic tests are used to assess the mechanical sensitivity of the nerve. However, very little is known about the reliability of upper limb neurodynamic tests, especially for the radial and ulnar nerves. The aim of this study was to evaluate the reliability of neurodynamic tests of the upper extremities including median, radial and ulnar nerves. Materials & Methods: in this observational cross-sectional study, using simple non-random sampling, 25 asymptomatic subjects, ranging in age from 19-45 years participated. The reliability of each median, radial and ulnar neurodynamic tests was examined. The neurodynamic tests were performed by two examiners in two successive days. During the neurodynamic tests, participants reported the initial stretching pain and the moment of submaximal pain (substantially obvious pain) in related area of nerve distribution, including anterior of elbow and forearm for median nerve, posterolateral aspect of elbow and forearm for radial nerve, and medial side of elbow and forearm for ulnar nerve. At the starting point of painful stretching and the submaximal pain, the angle of elbow extension (for median and radial nerve tests) and shoulder abduction angle (for ulnar nerve test) were measured using a mechanical goniometer. The range between two these points was used to analysis of reliability. ICC and SEM were calculated to examine the relative and absolute reliability respectively. Using t-test, the difference in the mean of the measurements was calculated. Results: No significant difference was found between the mean of measurements of two testers in intra-session and inter-session reliability. respectively for examiner 1 and 2, was obtained 0.94  (SEM:2˚) and 0.89 (SEM:2.85 ˚) for median nerve, 0.56 (SEM: 6.36˚) and 0.93 (SEM:1,82 ˚) for radial nerve, and 0.42 (SEM:3.27 ˚) and 0.79  (SEM:1.42 ˚) for ulnar nerve. Inter-tester intra-session reliability was obtained 0,84 (SEM: 3,44˚), 0,54 (SEM: 6,1˚) and 0,55 (SEM: 2.75˚) respectively for median, radial and ulnar nerves. Inter-tester inter-session reliability was obtained 0.97 (SEM:1.43˚), 0.69 (SEM: 5.06˚) and 0.51 (SEM: 2.8˚) respectively for median, radial and ulnar nerves. Conclusion: The upper limb neurodynamic tests and measurement of the range between the onset of stretching pain and point of submaximal pain have moderate to excellent reliability; Therefore, these clinical tests can be used in diagnostic evaluations and assessing the effects of treatment interventions. Also, median nerve neurodynamic test has a higher relative reliability than radial and ulnar nerve neurodynamic tests.