Diagnostic accuracy of patient interview items and clinical tests for cervical radiculopathy

Key Points

1. If the patient’s arm pain is worse than their neck pain, their symptoms are increased when ironing and reduced by walking with their hand in their pocket, this increases the likelihood of cervical radiculopathy.
2. A positive Spurling test and/or presence of reduced reflexes increases the likelihood of cervical radiculopathy.
3. The likelihood of cervical radiculopathy decreases if the patient does not experience paraesthesia or numbness.

BACKGROUND & OBJECTIVE

Currently, there are no agreed criteria to diagnose cervical radiculopathy. Therefore, the aim of this study was to determine the accuracy of patient interview items and clinical tests performed by a physiotherapist to diagnose cervical radiculopathy. In this paper, radiculopathy was considered to encompass all signs and symptoms that could occur due to nerve root compression, including both radiculopathy (referring to objective neurological deficits) as well as those presenting with radicular pain (which occurs in consequence of inflammation or compression of a nerve root).

Currently, there are no agreed criteria to diagnose cervical radiculopathy.

The information from this study should help clinicians make decisions on the best conservative management options and the need for referral for further investigations.

METHODS

134 patients with a median pain duration of 22 weeks were included in the study, and 66 (49%) were later diagnosed with cervical radiculopathy by a neurosurgeon. This diagnosis was based on both the patient presentation and relevant MRI results demonstrating nerve root compression or irritation. The participants completed a patient interview list and then a clinical physiotherapy assessment prior to the neurosurgical diagnosis being made to ensure blinding of both the patient and therapist.

The patient interview items included were chosen after a focus group was conducted with two experienced physiotherapists, a neurosurgeon and an orthopaedic surgeon. The clinical tests were chosen based on current literature and focus group input, and included the Spurling test, upper limb neurodynamic test for the median nerve (ULNT1), shoulder abduction relief test, cervical distraction test, and a clinical neurological examination. The physiotherapist who performed the clinical tests was blinded to the patients’ answers on the patient interview list.

RESULTS

Patients with radiculopathy more frequently reported a higher intensity of arm pain but less intensity of neck pain compared to those without. Radiculopathy at C6/7 was most common and rarely seen at C5 or C8. They also reported significantly higher levels of neuropathic pain medication use and neurological symptoms. There were no differences with respect to age, gender, disability, pain DETECT score (1), employment status, or reported muscle weakness.

The interview items ‘arm pain worse than neck pain’, ‘provocation of symptoms when ironing’, and ‘reduction of symptoms by walking with your hand in your pocket’ showed a high specificity (81-85%), suggesting that the presence of these items more likely suggests the patient has radiculopathy. However, these had lower sensitivity (14-58%), suggesting that the absence of these items did not always indicate the patient does not have radiculopathy.

Conversely, the interview items ‘presence of paraesthesia’ and ‘presence of paraesthesia and/or numbness’ showed high sensitivity (83-88%), suggesting that when these are not present radiculopathy is less likely. However, these items had poor specificity (37-41%). Therefore, overall, the likelihood ratios all of these patient interview items were of limited value in isolation.

In the clinical examination, the Spurling test (84%) and reduced reflexes (81%) had the highest specificity. Sensitivity of these measures was 57% and 55% respectively. This suggests that positive findings in these tests increases the likelihood of cervical radiculopathy, and negative results may somewhat reduce the likelihood of cervical radiculopathy. However, none of the clinical tests showed very high sensitivity, indicating that negative tests cannot be used to rule out radiculopathy.

LIMITATIONS

The results of this study were different to other studies for certain interview items or clinical measures where either small sample sizes and/or a different gold standard was used to diagnose the radiculopathy (2). There is debate as to the best reference standard to use for cervical radiculopathy, and in some studies the gold standard was needle electromyography which focuses more on pathophysiology rather than patho-anatomy which was used in the current study using MRI. This makes comparison to other studies difficult.

Furthermore, in clinical practice clinicians would not use single items, and would instead use information obtained in the patient interview together with the clinical examination with sound clinical reasoning to make a decision. It would therefore be helpful to determine the diagnostic value when considering combinations of patient interview items and clinical tests such as those identified in the current study.

CLINICAL IMPLICATIONS

The authors concluded that during the patient interview if the patient’s arm pain is worse than their neck pain, symptoms increase when ironing and/or reduce by walking with their hand in their pocket, this increases the likelihood of cervical radiculopathy. Additionally, if there is a positive Spurling test and/or presence of reduced reflexes demonstrated in the clinical examination, this further increases the likelihood of cervical radiculopathy. The likelihood of cervical radiculopathy decreases if the patient does not experience paraesthesia or numbness.

Also of interest is that no adverse events occurred from performing the clinical tests or the reference standard. This is relevant because the Spurling test has previously been shown to have potential for poor tolerance (3). There are also several different variations of this test described and inconsistency in how it is performed in clinical practice (4). The method used in this study involved passive neck extension, rotation and lateral flexion. Further, in this study compression was only added if symptoms had not been provoked. The test was considered positive if symptoms were reproduced.

This method, along with staged movement manoeuvrers, has been recommended to avoid unnecessary aggravation of symptoms (3). However, the duration of symptoms in this study and other studies using this test (3, 4) suggests that the majority of participants were in the subacute or chronic phase of the condition, so clinicians may need to use more caution with this test in the acute phase.

Overall, the information from this study should help clinicians to make decisions 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.

+STUDY REFERENCE

Sleijser-Koehorst M, Coppieters M, Epping R, Rooker S, Verhagen A & Scholten-Peeters G (2021) Diagnostic accuracy of patient interview items and clinical tests for cervical radiculopathy. Physiotherapy, 111, 74–82.

SUPPORTING REFERENCE

1. Freynhagen R, Baron R, Gockel U, Tölle TR. painDETECT: a new screening questionnaire to identify neuropathic components in patients with back pain. Curr Med Res Opin 2006; 22(10): 1911-20.
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. Anekstein Y, Blecher R, Smorgick Y, Mirovsky Y. What is the best way to apply the Spurling test for cervical radiculopathy? Clin Orthop Relat Res 2012; 470(9): 2566-72.
4. Jinright H, Kassoff N, Williams C, Hazle C. Spurling's test - inconsistencies in clinical practice. J Man Manip Ther 2021; 29(1): 23-32.