Upper limb neurodynamic test 1 in patients with clinical diagnosis of carpal tunnel syndrome: A diagnostic accuracy study

Study Design: Diagnostic accuracy. Introduction: Upper limb neurodynamic test 1 (ULNT1) is used to evaluate the mechanical sensitivity especially in the peripheral nerves of the upper limbs. The reproduction of typical symptoms in the affected hand improves the estimation of the probability of carpal tunnel syndrome (CTS). However the test has not been evaluated sufficiently to determine its real usefulness. In the present study the diagnostic accuracy of ULNT1 as a clinical test for CTS was determined. Methods: We used the ULNT1 as the index test and nerve conduction as the reference standard. 120 subjects, (240 hands), with a medical diagnosis of CTS were evaluated. The study population was a consecutive series of participants. Sensitivity, specificity, positive and negative predictive values, accuracy, and positive likelihood ratio were calculated. Results: ULNT1 was found to have a sensitivity of 93 % and a specificity of 6.67 %. The positive likelihood ratio was 1.04 and the negative likelihood ratio was 1.00. The positive predictive value was 86.9 % and the negative predictive value was 12.5%. Discussion: Acute or relatively mild CTS cases may not be accurately identified through nerve conduction tests. The findings of this study coincide with other studies in the finding that ULNT1 has a significant diagnostic and clinical screening value for CTS in people at-risk, or with upper limb symptoms. Conclusion(s): This research suggests the use of ULNT1 as a screening test for CTS, followed by tests that are more specific. Level of Evidence: III-2.