The resisted levator scapulae test: a clinical test for C4 radiculopathy.

Abstract

Purpose: Cervical radiculopathy results from compression of a nerve root in the cervical spine creating upper limb or shoulder girdle sensorimotor dysfunction which commonly affects the C5-8 roots. Isolated C4 radiculopathy is rare and lacks typical clinical radiculopathy features and, as a result is underreported and poorly diagnosed. Nerve blocks can be used on the basis of pain distribution and clinical suspicion, however, no bedside tests exist to identify and test C4 radiculopathy in isolation. The objective of our study was to assess the clinical utility of using the Resisted Levator Scapulae test in identifying patients with C4 radiculopathy on physical exam.

Methods: Participants were recruited on the basis of clinical suspicion of C4 radiculopathy. Participants were separated into test and pragmatic control based on radiographic evidence of C3/4 foraminal stenosis. Test group patients received the reference standard CT guided nerve root injection, pragmatic control patients were classed based on imaging. The reference standard was performed after review with a spinal surgeon where the RLS test result was recorded. Data was collected with primary and expanded analyses providing data for for predictive values using a contingency table.

Results: Twenty-five participants (12 male, 13 female) with a median age of 69 completed the study in the test group, with 298 participants (192 male, 106 female) completing the study in the pragmatic control group. Nine test group participants (2.8%) showed isolated C4 radiculopathy with response to the diagnostic CT guided C4 nerve block, while 15 (4.6%) had multilevel involvement including C4. Primary analysis revealed sensitivity of 90% and specificity of 20% with an odds ratio of 2.25 (confidence interval: 0.2-25.4). Expanded analysis strengthened specificity (93%) and NPV (99.6%).

Conclusion: The resisted levator scapulae test is a novel bedside physical diagnostic test for C4 radiculopathy used to complement a neurological examination and raise suspicion when positive.