Cervical Myelopathy

Overview

Cervical myelopathy is a clinical syndrome caused by compression and dysfunction of the spinal cord within the neck. In adults, the most common cause is degenerative cervical myelopathy, sometimes called cervical spondylotic myelopathy, in which age-related changes gradually narrow the spinal canal and squeeze the cord. The anatomy at play includes the cervical vertebrae, intervertebral discs, facet and uncovertebral joints, and the ligaments that line the canal; all of these structures can contribute to narrowing over time. The underlying injury to the cord comes from two overlapping mechanisms: direct mechanical compression reduces the canal's diameter, while repetitive bending and extending of the neck produces additional strain. Chronic pressure disrupts the blood supply to the cord and injures both the insulating myelin sheaths and the nerve fibers themselves, producing the characteristic mix of motor, sensory, and coordination problems.

What causes it

Degenerative change is the dominant cause and is most common in middle-aged and older adults, with incidence rising as spondylotic change accumulates over the decades. Men are affected somewhat more often than women. A congenitally narrow cervical canal is an important risk factor. People born with a smaller-than-average canal can develop symptomatic compression from only modest degenerative change. Ossification of the posterior longitudinal ligament, a condition more prevalent in East Asian populations, is another significant contributor. Other risk factors include occupational or recreational repetitive neck loading, prior cervical trauma, and inflammatory conditions such as rheumatoid arthritis that can destabilize the upper neck. Although degenerative disease accounts for the majority of cases, cord compression can also arise from a spinal tumor, infection, or acute trauma, possibilities that change both urgency and management.

Symptoms and warning signs

The onset of cervical myelopathy is typically insidious, and progression is often stepwise rather than a smooth decline. Patients commonly notice hand clumsiness first (struggling with buttons, coins, zippers, or utensils) along with deterioration of handwriting and a sense of generalized weakness. Gait imbalance and a feeling of unsteadiness on uneven ground are hallmarks. Sensory complaints, neck stiffness, vague arm pain, and bladder urgency may appear as the condition evolves.

On examination, a physician looks for upper motor neuron signs below the level of compression: brisk reflexes, clonus, a positive Hoffmann sign in the hands, an extensor plantar (Babinski) response, a positive Lhermitte sign (electric-shock sensation down the spine with neck flexion), and a broad-based or spastic gait. Wasting of the small muscles of the hands may accompany these findings when a nerve root is also involved.

Certain features should prompt urgent rather than routine evaluation. Rapidly progressive weakness, acute neurological decline, new bowel or bladder dysfunction, or a broad-based gait that worsens quickly should not be managed with watchful waiting. Fever, immunosuppression, a history of intravenous drug use, or known cancer with new spine symptoms raise concern for infection or malignancy and require immediate imaging and specialist assessment.

How it's diagnosed

Diagnosis depends on correlating the history and neurological examination with imaging findings. MRI is the investigation of choice: it shows the degree and levels of cord compression, the dimensions of the canal, and any intramedullary T2-signal change, a bright area within the cord on MRI that can reflect edema, scarring, or permanent injury and carries prognostic significance. CT is valuable for characterizing bony narrowing, osteophytes, and ligament ossification; CT myelography is used when MRI is contraindicated or insufficient. Plain radiographs, including flexion and extension views, assess alignment, degenerative change, and instability.

Because cervical stenosis is common on imaging in asymptomatic people, findings must always be interpreted alongside symptoms and physical signs. An MRI finding alone does not make the diagnosis. Electrodiagnostic studies help separate cord-level disease from peripheral mimics such as carpal tunnel syndrome, cubital tunnel syndrome, peripheral neuropathy, and shoulder pathology. These peripheral conditions produce lower motor neuron or focal patterns and lack the long-tract signs (overactive reflexes, gait disturbance, and bladder change) that point to the spinal cord.

Treatment options

Management is guided by symptom severity and the trajectory of the condition. For mild disease that has not been progressing, conservative measures (activity modification, physical therapy, and avoidance of high-risk neck positions) combined with close clinical monitoring may be appropriate. It is important to understand that there is no strong evidence nonoperative care reverses established cord damage; the goal of conservative management is to minimize additional stress and to watch carefully for any sign of deterioration. Injections and other procedures that address pain from concurrent radiculopathy may provide symptom relief but do not treat the underlying cord compression.

Surgical decompression is the recommended treatment for moderate to severe myelopathy and for any disease that is progressing. Surgery aims to halt deterioration and, in many patients, to improve function. Outcomes are generally better when surgery is performed before substantial cord injury has accumulated, which is why prompt recognition and referral matter.

When surgery is considered

Surgery is indicated for moderate to severe or progressive cervical myelopathy. The urgency is heightened when there is rapid neurological decline, acute deterioration, or any presentation suggesting infection or tumor. Those situations require urgent surgical evaluation rather than elective scheduling.

The choice of surgical approach depends on the number of compressed levels, the location of the compression (front versus back of the cord), and the alignment of the cervical spine. Anterior approaches, removing the disc or a vertebral body and fusing the segment, address compression arising from the front of the canal and are common when one to two levels are involved. Posterior approaches, including laminectomy with fusion or laminoplasty, expand the canal from behind and are suited to multilevel disease or cases where the cord is compressed primarily from the rear. Surgeons tailor the recommendation to each patient's anatomy, imaging findings, and overall health, with the goal of protecting the cord from further injury and restoring as much function as possible.