Diagnostic accuracy of upper limb neurodynamic tests for the assessment of peripheral neuropathic pain: A systematic review

Background: Upper limb neurodynamic tests (ULNTs) are used to identify a neuropathic pain component in patients' presenting with arm and/or neck pain. Clinical tests with established diagnostic accuracy are required to not only to inform clinical management but also minimise costs associated with expensive medical investigations. Objective: To evaluate the role of ULNTs in assessment of peripheral neuropathic pain and to inform their value in clinical practice when assessing patients with arm and/or neck symptoms. Design: Systematic review was undertaken according to published guidelines, and reported in line with PRISMA-DTA. Method: Key databases were searched up to 21/11/2017. Inclusion criteria: Patient population experiencing arm and/or neck symptoms with suspected peripheral neuropathic involvement, studies that compared ULNT to a reference standard, any study design using primary diagnostic accuracy data. Two reviewers independently assessed risk of bias (ROB) using QUADAS-2. The overall quality of evidence was evaluated using GRADE. Results: Of eight included studies (n = 579), four were assessed as low ROB, although all had concerns regarding applicability. For carpal tunnel syndrome, ULNT1 sensitivity values ranged 0.4-0.93, specificity 0.13-0.93, positive likelihood ratio 0.86-3.67 and negative likelihood ratio 0.5-1.9. For cervical radiculopathy ULNT1 and the combined use of four ULNTs had sensitivity of 0.97 (95% CI 0.85-1.00) whereas the ULNT3 was the most specific (0.87, 95% CI 0.62-0.98). Positive likelihood ratio ranged 0.58-5.68 and negative likelihood ratio 0.12-1.62. Conclusion: Based on the available evidence ULNTs cannot be utilised as a stand-alone test for the diagnosis of CTS. Limited evidence suggests that ULNTs may be clinically relevant for the diagnosis of CR, but only as a "ruling out" strategy. However, the overall quality of the body of evidence after applying the GRADE approach was low to very low across studies. Further higher quality research is needed to establish firm conclusions.