What is needed to diagnose cervical radiculopathy?

From the Guidelines

Diagnosing cervical radiculopathy requires a comprehensive approach that typically starts with a thorough clinical evaluation, including history and physical examination, and may not necessarily require immediate imaging in the absence of red flag symptoms, as suggested by 1 and 1. To diagnose cervical radiculopathy, the following steps are essential:

• A thorough history to identify neck pain that radiates into the arm in a dermatomal pattern, along with associated neurological symptoms like numbness, tingling, or weakness.
• A physical examination that includes testing of muscle strength, deep tendon reflexes, and sensory function, as well as provocative tests such as the Spurling test, shoulder abduction test, and neck distraction test, as these can help identify the affected nerve root and rule out other conditions. Imaging studies, particularly MRI, are crucial for confirmation and to visualize nerve root compression and potential causes like herniated discs or foraminal stenosis, but according to 1, in the absence of red flag symptoms, imaging may not be required at the time of initial presentation.

Key Diagnostic Tools

• MRI: The gold standard for visualizing soft tissue and nerve root compression, with studies like 1 highlighting its superiority over other imaging modalities for evaluating the cervical spine in suspected nerve root impingement.
• X-rays: May be ordered initially to rule out bony abnormalities.
• CT scans: Can better visualize bony structures when needed.
• Electrodiagnostic studies (EMG and nerve conduction studies): May be used to confirm the diagnosis and rule out other conditions like peripheral neuropathy. Given the potential for both false-positive and false-negative findings on MRI, as noted in 1, a comprehensive approach combining clinical evaluation and diagnostic testing is necessary for an accurate diagnosis. The presence of red flag symptoms, such as trauma, malignancy, or systemic diseases, necessitates immediate imaging, as indicated by 1 and 1. In real-life clinical practice, prioritizing a thorough clinical evaluation and judicious use of diagnostic testing based on the presence of red flag symptoms or the severity of symptoms is crucial for optimizing patient outcomes and minimizing unnecessary testing.

From the Research

Diagnosis of Cervical Radiculopathy

To diagnose cervical radiculopathy, several factors are considered, including:

• History and physical examination, as the diagnosis can be established by these means, but care should be taken due to potential mimicry or coexistence with other conditions like entrapment neuropathies 2
• Various physical tests, such as Spurling's test, which has shown high specificity but variable sensitivity 3
• Supplementary tests, including MRI without contrast, CT scanning, and in some cases plain radiography, with MRI recommended prior to interventional treatments 4
• A combination of patient history, physical examination, and diagnostic imaging, as the diagnosis is based on information from these sources 3

Components of the Diagnosis

The diagnosis of cervical radiculopathy may involve:

• Clinical examination items, such as reduced tendon reflexes, which have been found to be specific, and somatosensation testing, which has been found to be less sensitive 5
• Self-report measures, which can be used in conjunction with clinical examination items to assess the diagnosis 6
• Neurological examination, which is essential for diagnosing cervical radiculopathy according to the International Association for the Study of Pain definition, but its diagnostic accuracy remains unclear 5

Diagnostic Accuracy

The diagnostic accuracy of various tests and components for cervical radiculopathy has been studied, with findings including:

• High specificity of Spurling's test, ranging from 0.89 to 1.00, but variable sensitivity, ranging from 0.38 to 0.97 3
• A diagnostic test item cluster of four variables, which produced a positive likelihood ratio point estimate of 30.3, but with wide 95% confidence intervals 6
• Varying operational definitions of radiculopathy, suboptimal reference standards, and great heterogeneity in the neurological examination procedure and its diagnostic accuracy, highlighting the need for further research 5