Diagnostic usefulness of denervation edema in the multifidus muscles using 3-Tesla magnetic resonance imaging in cervical radiculopathy.

Abstract

Diagnosing cervical radiculopathy (CR) can be difficult because of symptomatic overlap with peripheral neuropathies. In this retrospective observational study, we aimed to determine whether short-tau inversion recovery (STIR) magnetic resonance imaging (MRI) sequences are useful for detecting signs of denervation in the multifidus muscles in patients with CR. We analyzed the data of 18 patients with CR who developed arm weakness within 1 year. We also included 10 patients with sensorimotor symptoms involving the upper extremities who did not have intervertebral foraminal stenosis on MRI as controls. For each patient with CR, the signal intensity (SI) of the affected multifidus muscles was measured and compared to that on the contralateral side (signal intensity ratio: SIR). Control patients without CR did not exhibit STIR signal abnormalities in the multifidus muscles. Most of the 18 patients with CR were male (83.3%), and the mean age was 59.4 years. Thirteen of 18 CR patients (72.2%) were determined to have STIR signal abnormalities by a radiologist. The mean SIR in the 13 patients with increased SI was significantly higher than that in the five patients without signal abnormalities (1.23 vs 0.97, P = .004), supporting the radiologist's diagnosis. The distribution of signal abnormalities closely followed those identified via clinical and electrophysiological tests, especially severe weakness (P = .044). Denervation edema of the multifidus muscles can be detected in CR and correlates with clinical/electrophysiological tests and weakness severity, which may aid in CR diagnostics.