Diagnostic accuracy of upper limb neurodynamic tests in the diagnosis of cervical radiculopathy

Key Points

1. If the patient has 3/4 positive upper limb neurodynamic tests (ULNT) it increases the likelihood of cervical radiculopathy (CR), but doesn’t rule it out.
2. No positive tests significantly decrease the likelihood of CR and generally rule it out.
3. All four tests (ULNT1, 2a, 2b and 3) should be assessed to assist diagnosis of CR.

BACKGROUND & OBJECTIVE

Upper limb neurodynamic tests (ULNT) are used to help diagnose several neuropathic conditions. The aim of this study was to determine the accuracy of ULNTs performed by a physiotherapist to diagnose cervical radiculopathy (CR). The authors specifically aimed to determine if using more rigid definitions of a positive test could improve the diagnostic accuracy, and whether results from a combination of tests were better than individual tests.

Upper limb neurodynamic tests are used to help diagnose several neuropathic conditions.

This study highlights the importance of using both pain reproduction as well as structural differentiation as the criteria for a positive ULNT for differential diagnosis of cervical radiculopathy.

METHODS

85 patients with arm pain with or without neck pain were included in the study. 58 were diagnosed without CR and 27 with CR by an experienced neurosurgeon based on both the patient presentation and relevant MRI results demonstrating nerve root compression or irritation. Patients were then assessed by a physiotherapist who was blinded to both the patient’s history and diagnosis.

ULNTs for the median (ULNT1 and 2a), radial (ULNT2b), and ulna nerve (ULNT3) were performed in a randomized order with 5 minutes rest between each test. In this paper, the definition of a positive test was both “reproduction of a familiar symptomatic complaint of arm pain and/or neck pain at least partially (pain or dysesthesia including burning, or lightning-like pain, or tingling sensation), and the pain was changed with structural differentiation using known sensitizing manoeuvres” (1).

RESULTS

• There were no differences between groups for age, gender, neck pain intensity, disability or duration. On average patients had moderate pain and disability.

• All tests were more specific (>72%) - i.e. a negative test indicating no CR, than sensitive (<70%) – i.e. a positive test indicating CR; with the ULNT3 the most specific at 93% and the ULNT2b the most sensitive at 71%.

• The use of results from one test in isolation to rule CR in or out was not as useful as using the combination of tests.

• No positive tests out of four can rule out CR with 96% certainty. On the other hand, 3 out of 4 positive tests can rule in CR with 86% certainty. Although, it should be recognised that only 12/27 of the patients with CR had 3 of 4 positive tests, so less than 3/4 tests should not be used to rule out CR.

• These results were higher than previously reported studies, which the authors attributed to the rigid criteria for a positive test used in the study. Previous studies had used the presence of pain or structural differentiation (not both criteria), and had not found ULNTs to be useful for ruling in CR (2).

LIMITATIONS

The authors suggest that the sample size could have been larger. Furthermore, the examiner in the study had 10 years of experience with advanced certification for orthopaedic assessment. Therefore, it is not known whether the results can be generalized when inexperienced clinicians perform the tests.

CLINICAL IMPLICATIONS

The findings from this study highlight the importance of using both pain reproduction as well as structural differentiation as the criteria for a positive ULNT for differential diagnosis of CR. A recent paper (which I reviewed in the June issue of Physio Network) explored the diagnostic accuracy of patient interview features and other tests for CR. It found that if the patient’s arm pain is worse than their neck pain; symptoms are increased when ironing and/or reduced by walking with their hand in their pocket; there is a positive Spurling test and/or presence of reduced reflexes; then there is increased likelihood of CR. Further, CR is less likely if the patient does not experience paraesthesia or numbness (3).

Overall, the information from both of these studies might help clinicians to make decisions to rule CR in or out, and then decide on the best conservative management options and the need for referral for further investigations such as medical imaging or medical management, in patients presenting with neck and arm pain.

Of interest, no adverse events occurred from performing the clinical tests or the reference standard. However, the method used in this study involved the patient’s head positioned on the bed with no pillow and the four neurodynamic tests were performed 5 minutes apart to limit pain exacerbation. This might not be feasible in the clinical setting and clinicians should use caution when conducting this suite of measures, especially if the patient is reporting acute or irritable pain.

+STUDY REFERENCE

Grondin F, Cook C, Hall T, Maillard O, Perdrix Y & Freppel S (2021) Diagnostic accuracy of upper limb neurodynamic tests in the diagnosis of cervical radiculopathy. Musculoskeletal science & practice, 55, 102427.

SUPPORTING REFERENCE

1. Nee RJ, Jull GA, Vicenzino B, Coppieters MW. The Validity of Upper-Limb Neurodynamic Tests for Detecting Peripheral Neuropathic Pain. J Orthop Sports Phys Ther 2012; 42(5): 413-24.
2. Thoomes EJ, van Geest S, van der Windt DA, et al. Value of physical tests in diagnosing cervical radiculopathy: a systematic review. Spine J 2018; 18(1): 179-89.
3. Sleijser-Koehorst MLS, Coppieters MW, Epping R, Rooker S, Verhagen AP, Scholten-Peeters GGM. Diagnostic accuracy of patient interview items and clinical tests for cervical radiculopathy. Physiotherapy 2021; 111: 74-82.