Cervical Radiculopathy

Etiology

Any condition that causes compression or irritation of a spinal nerve root can result in radicular symptoms. In younger patients, typically in the third and fourth decade, disc trauma and herniation are the most frequent causes of impingement. [4]With increasing age, the causation becomes largely degenerative. In the fifth and sixth decades, disc degeneration becomes the most common cause. In the seventh decade, causation tends to stem from foraminal narrowing as a result of arthritic change.

Epidemiology

Less frequent than lumbar radiculopathies, cervical radiculopathies occur at an incidence rate of approximately 85 persons per 100,000. Most frequently impacted is the C7 nerve root with greater than half of all cases affecting this level. Approximately a quarter of cases affect the C6 nerve root. Other levels are impacted at a much lower rate. Risk factors for developing the radicular disease include manual labor involving heavy lifting, driving, or operation of vibrating equipment. History of chronic smoking increases the risk of developing radiculopathies.

Pathophysiology

In nearly all cases of cervical radiculopathy, the key pathophysiologic feature is inflammation. That inflammation can result from acute herniation of an adjacent cervical disc that subsequently impinges on the nerve root. The inflammation also can exacerbate degenerative changes to such a degree that osteophytes or changes associated with disc dehydration can impinge on the nerve root. It is the direct compression of the nerve root that creates the symptomatology.

History and Physical

The history in patients with a complaint of radicular pain or muscle weakness should include inquiring about occupational risk factors, history of trauma and pain pattern. Cervical radiculopathy is almost always unilateral, although, in rare cases, both nerves at a given level may be impacted. Those rare presentations can confound physical diagnosis and require acceleration to advanced imaging especially in cases of trauma.

On physical examination, positioning the patient to isolate individual reflex arcs is key. Given the individual variation in deep tendon reflexes comparing side to side is more important than overall magnitude. If there is nerve impingement, the affected side will be reduced relative to the unaffected side. Reduction in strength of muscles innervated by the affected nerve is also significant physical finding.

Spurling test, which compresses the foramina, is useful in diagnosing likely radiculopathy. With the head extended, the head should then be rotated. The test is positive if the pain radiates down the upper limb of the ipsilateral side of the rotation.

In some cases, cervical traction can provide relief of radicular pain.

Evaluation

Three-view plain x-ray studies of the cervical spine are the most common studies ordered for evaluation of neck and upper extremity pain. Lateral views may show disc space narrowing. Oblique views may show foraminal narrowing at the level of radicular symptoms. Open mouth views are only necessary if disruption of the atlantoaxial joint is suspected.[5][6][7][8]

Computed tomogram (CT) scanning may be useful in the acute setting for the diagnosis of traumatic injuries resulting in radicular symptoms. Poor visualization of soft tissue makes CT less effective outside of this setting.

Magnetic resonance imaging (MRI) is the imaging method of choice for evaluating radiculopathies. MRI provides excellent visualization of soft tissue abnormalities including disc herniations and nerve compressions. There is a risk of falsely positive MRI studies as disc herniations and foraminal narrowing, while strongly correlated with radicular symptoms, may not be causative in any individual case.

Electromyography can be useful in confirming the dysfunction of the affected nerve root.

Selective nerve root blocks can be used not only as a treatment adjunct to provide short-term pain relief to patients with radicular pain but also can be effective in confirming nerve root origins of radiated pain.

Treatment / Management

Treatment of cervical radiculopathy should be approached in a stepwise fashion. Also, while surgery can provide significant relief, there is little evidence that surgery provides a clear advantage over non-surgical treatment in an acute setting. Over 85% of acute cervical radiculopathy resolves without any specific treatments within 8-12 weeks. [9][10][11] (A1)

Over 85% of acute cervical radiculopathy resolves without any specific treatments within 8-12 weeks.  However, in order to facilitate reduced inflammation of the nerve root(s) and improve radiculopathy, it is important to implement non-surgical treatments including oral anti-inflammatory drugs,  physical therapy, and translaminar epidural steroid injections. 

An aggressive, well-designed physical therapy program can provide significant relief. In the setting of surgical intervention physical therapy can speed recovery.

Medical durable goods and appliances can provide significant symptom relief. Nighttime use of a cervical pillow can provide symptom relief and make sleeping easier during recovery. Short term use of a soft cervical collar can provide some support and relief. 

Since the main cause of pain in cervical radiculopathy is inflammation use of non-steroidal anti-inflammatory drugs (NSAIDs) for 1 to 2 weeks can provide not only symptom relief but also treat the proximate cause. The use of oral steroids is controversial, and dosing should be short term if at all. Tricyclic antidepressants and drugs such as gabapentin can be useful adjuncts in the treatment of cervical radiculopathy. Opioid pain medications are not recommended but can have utility in the management of radicular pain. It should be noted that the use of opioid medications is a risk factor for the slow recovery and delayed return to work for patients where surgical intervention becomes clinically necessary.[12][13](B2)

Studies have shown that epidural steroids can provide significant relief and speed return to normal functioning for many patients. Relief from a single treatment can be significant and long-lasting. Half of the patients treated have reported relief of at least 50% for weeks following injection.

Using acupuncture as an adjunctive therapy also has shown to provide significant relief of symptoms. A direct physical manipulative technique such as chiropractic or direct osteopathic manipulation can worsen radicular symptoms. Indirect osteopathic techniques conversely can facilitate relief of symptoms. 

Surgical management of radicular pain can provide relief in patients that are failed non-surgical treatments. Surgical techniques can be done utilizing anterior or posterior approaches.  Usually, the anterior approach requires complete discectomies filled by fusion or disc replacements.  The posterior approach involves laminectomy, partial discectomy, and foraminotomy with or without fusion. Both approaches are found to be effective.  As always, surgical treatments are reserved for failed non-surgical treatments and patients have acute deterioration of their neurological function.   No matter the approach, surgery-related complications can occur including complications caused by anesthesia or complications from the procedure itself including nerve palsies, vascular impairment, and laryngeal nerve damage.

Differential Diagnosis

• Brachial plexus injury in sports medicine

• Cervical disc injuries

• Cervical discogenic pain syndrome

• Cervical facet syndrome

• Cervical spine sprain

• Rotator cuff injuries

• Strain injuries