Diagnosis of Cervical Disc Herniation

X-Ray of the cervical spine in order to see the alignment of the spine, the shape of the vertebral bodies, and the spaces between them, as well as the characteristics of the holes where the nerves come out (intervertebral foramen).

Dynamic radiography of the cervical spine, in flexion and extension positions of the neck. This is used to find out if there is instability between the vertebrae that could explainthe origin of the disc herniation.

Magnetic Resonance (MR). It is currently the preferred test. Thanks to this test, the morphology is clearly seen, as well as the relationship of the intervertebral disc with the surrounding anatomical components.  

CT or cervical spine scan. From a surgical point of view, this test rarely has a diagnostic capacity at cervical spine level. Bones are large and it is difficult to obtain clear images of a disc herniation. However, it can be useful as a complement test to MR, in order to make a better assessment of whether the disc is hard (osteophyte) or soft.

Electromyogram. Although this is an uncomfortable test for the patient, it helps to differentiate the affected nerve root, using a study of nerve conduction towards the muscles. It is used in patients whose cervical spine has several discs affected and the Magnetic Resonance cannot help to identify which disc causes the symptoms that the patient is suffering.

Evoked potential test. This test is similar to an electromyogram; although, instead of evaluating nerve function, it studies the functional integrity of the spinal cord. It is used in all patients affected by cervical spondylotic myelopathy, both to evaluate changes in nerve transmission through the spinal cord and to determine the baseline status of the latter during the preoperative study.