Cervical Disk Disease
Cervical Disk Disease
Kevin Eerkes
Basics
Description
-
Cervical radiculopathy is defined as neurogenic pain in a dermatomal distribution ± numbness, weakness, and decreased reflexes in the upper limb.
-
This is caused by compression or irritation of the nerve root.
-
The most common location is the neural foramen.
Epidemiology
-
Predominant age: Peak age for cervical radiculopathy is 50–54 yrs.
-
Predominant gender: Female > Male; women are more likely to suffer from cervical disk disease than men at an earlier age.
Incidence
Annual incidence rates of cervical radiculopathy:
-
107.3 cases/100,000 men
-
63.5 cases/100,000 women (1)
Etiology
-
Cervical radiculopathy occurs when the nerve root becomes dysfunctional from compression, stretching, and/or irritation.
-
The most common cause is degenerative changes of the cervical spine. Degenerative changes become more prominent with age and encompasses the following:
-
Desiccation and bulging of the disks
-
Osteophyte formation at the uncovertebral and facet joints
-
Loss of disk height
-
These all may lead to narrowing of the neural foramen through which the nerve exits.
-
-
Disk herniation is the 2nd most common cause of cervical radiculopathy.
-
This also tends to occur in an older population with some disk degeneration.
-
Can occur in younger population (<45 yrs old), but more force generally is needed because their disks are more resilient.
-
Pathophysiology:
-
The annulus fibrosis becomes weakened, allowing the nucleus pulposus to herniate through.
-
The herniated disk material may compress the nerve root and incite the production of various inflammatory cytokines that irritate the nerve.
-
-
Pathoanatomy:
-
Cervical nerve roots exit above their correspondingly numbered pedicles.
-
C7 nerve root exits between C6 and C7.
-
C6 nerve root exits between C5 and C6.
-
Most common level for the herniation is C6–7 (70%), which affects the 7th cervical nerve.
-
C5–6 is the next most common level. Herniation here typically affects the 6th cervical nerve.
-
Most disk herniations occur in a posterolateral direction into the foramen.
-
The disk occasionally can herniate posteriorly, which may result in myelopathy (cord compression).
-
The presence of osteophytes narrows the canal, so a disk herniation (which further narrows the canal) more than likely would be symptomatic.
-
-
Diagnosis
History
-
Ask about prior neck or low back problems.
-
Usually the onset of symptoms is spontaneous or with only minor force to the disk.
-
The annulus is usually already weakened, so major force is not necessary for herniation.
-
Occasionally, the onset of symptoms is coincident with trauma such as axial loading and/or hyperflexion.
-
-
Pain radiates into the neck and the ipsilateral upper limb in a myotomal pattern.
-
A myotome is the muscle(s) innervated by a nerve. The myotome for the 6th and 7th cervical nerves would be the arm and forearm.
-
The upper limb pain may be greater than the neck pain.
-
Pain also may be referred to the upper trapezius, periscapular area, and shoulder girdle.
-
Patient may report relief by abducting the upper limb. This decreases the amount of stretch on the nerve root.
-
-
Numbness and paresthesia often occur in a dermatomal distribution.
-
For the 7th cervical nerve, this would occur down the limb to the middle finger.
-
For the 6th cervical nerve, this would occur down the limb to the thumb and index finger.
-
Note that this classic dermatomal pattern is not always present.
-
-
Weakness often develops in the muscles supplied by the nerve.
-
Red flags:
-
Gait disturbance, bowel/bladder dysfunction, or hand clumsiness (possible myelopathy)
-
Fever, chills, unexplained weight loss
-
Unremitting night pain
-
Immunosuppression
-
History of cancer
-
IV drug abuse
-
P.71
Physical Exam
-
Range of motion of the neck is decreased.
-
Neck tenderness is often present.
-
Muscle spasm may be present.
-
Strength and/or reflexes often decreased.
-
For the 7th and 8th cervical nerves, triceps weakness and diminished triceps reflex
-
For the 5th and 6th cervical nerves, weak deltoid, wrist extensors, and biceps; brachioradialis and biceps reflexes diminished
-
-
Sensation in dermatome may be decreased (see “History”).
-
Spurling's maneuver may be positive.
-
Neck extension combined with side bending and rotating to the ipsilateral side
-
This further narrows the neural foramen and may reproduce symptoms down the upper limb.
-
Accuracy is poor.
-
-
May check for signs of myelopathy:
-
Hoffmann sign: Flexion and adduction of the thumb when the examiner passively flexes the distal phalanx of the middle finger (while stabilizing the middle phalanx)
-
Hyperreflexia
-
Babinski sign
-
Lhermitte sign: Shocklike sensation radiating down the spine with simultaneous neck and hip flexion
-
Diagnostic Tests & Interpretation
Imaging
-
X-rays:
-
Obtain on initial visit if red flags; otherwise, optional
-
Anteroposterior, lateral, and oblique views
-
Images usually are not very helpful.
-
Often normal
-
May show nonspecific spondylosis
-
Athletes with a long history of involvement in collision sports have a higher rate of x-ray abnormalities.
-
Disk space narrowing occasionally may be seen at the level of the disk herniation.
-
-
-
MRI:
-
Provides excellent visualization of disks and nerves
-
Indications:
-
Symptoms or signs of myelopathy
-
Red flags suggestive of tumor or infection
-
Progressive or disabling neurologic deficit
-
No improvement after 4–6 wks of treatment
-
-
T2 images best show disk herniation.
-
Caution should be used when interpreting MRIs in contact athletes and older adults.
-
They have a high frequency of abnormal findings on MRI, many of which are asymptomatic.
-
MRI results should correspond with the physical findings to be significant.
-
The nerve root compromised on MRI must correspond to location of pain and weakness/reflex loss in the patient.
-
-
-
CT myelogram:
-
Only done if need information the MRI doesn't provide
-
Differentiates a soft disk (disk herniation) from a hard disk (osteophyte disk ridge complex)
-
Shows foraminal stenosis better than MRI
-
Disadvantage is that it is invasive.
-
Diagnostic Procedures/Surgery
Electrodiagnostic studies (nerve conduction study and/or electromyogram):
-
Obtain only if diagnosis is unclear or want to rule out peripheral nerve entrapment.
-
Wait until symptoms have been present at least 3 wks before testing. Testing sooner may result in false-negative result.
Differential Diagnosis
-
Cervical spondylosis
-
Osteophyte disk ridge complex (the remnants of a herniated disk combined with an osteophyte)
-
Annular tear
-
Peripheral nerve entrapment
-
Brachial plexus neurapraxia (“stinger”)
-
Thoracic outlet syndrome
-
Parsonage-Turner syndrome/brachial plexopathy
-
Myelopathy (with massive central disk herniation)
-
Spinal tumor
-
Spinal infection
-
Complex regional pain syndrome
-
Herpes zoster
-
Rotator cuff disorders
-
Pancoast tumor
-
Vascular disturbance
Treatment
-
Because of a relatively high rate of spontaneous resolution, initial treatment is usually nonoperative. Exceptions that may require further workup and subspecialty consultation include:
-
Progressive neurologic deficit
-
Disabling weakness
-
Infection or tumor
-
Vertebral fracture or subluxation from trauma
-
-
There are no controlled trials comparing the various nonsurgical treatment regimens with the natural history (ie, no treatment at all); therefore, it remains unclear whether nonsurgical management actually improves the natural history of the disorder or simply treats the symptoms as the disorder runs its course (2)[C].
-
Treatment recommendations are from case series and anecdotal experience.
-
The aim of treatment of disk herniation is to relieve pain and improve neurologic function while the herniated disk is absorbed by the body and the nerve dysfunction subsides. Resolution of the symptoms correlates with attenuation of the herniation on imaging studies.
-
Patients should be reevaluated at regular intervals during the treatment process so that worsening symptoms can be identified promptly.
P.72
Medication
First Line
-
NSAIDs:
-
Use at anti-inflammatory doses (eg, ibuprofen 600 mg q.i.d.).
-
Block formation of inflammatory mediators at the site of the disk herniation
-
Use cautiously if:
-
Risk factors for GI bleeding
-
Risk factors for renal disease
-
-
-
Oral steroids:
-
More potent anti-inflammatory agents than NSAIDs, although greater potential side effects
-
May consider using if:
-
Not responding to NSAIDs
-
Severe pain
-
Weakness
-
-
Avoid using with NSAIDs.
-
Have not been shown to alter the natural history of cervical radiculopathy
-
Dose:
-
Often corresponds to the degree of weakness
-
Typical regimen: Start with 50–70 mg/day of prednisone; taper over next 10 days (3)[C].
-
-
Side effects: Numerous, but significant side effects are rare if drug is taken in small doses for a limited length of time.
-
Second Line
-
Narcotics:
-
May be considered for short-term use if pain is severe and not controlled by other medications and modalities
-
Have additive effect with NSAIDs on pain relief
-
Typical prescription: Oxycodone (Vicodin) 1–2 pills q4–6h PRN for pain
-
Potential side effects: Drowsiness, vomiting, constipation, dependency
-
-
Antispasmodic agents (muscle relaxants):
-
Consider using if muscle spasm is prominent.
-
Additive effect on pain relief when used with a NSAID or narcotic; drowsiness when combined with a narcotic may be intolerable.
-
Typical prescription: Cyclobenzaprine (Flexeril) 5–10 mg t.i.d.
-
Avoid using for >2–3 wks.
-
Potential side effects: Sedation, dependency
-
Additional Treatment
-
Rest:
-
“Relative rest” is typically recommended. Patient is encouraged to be as active as the pain allows.
-
Bed rest:
-
Reserved for only the worst cases
-
Elevate head of bed
-
Limit to <7 days
-
-
-
Cervical collar to limit motion:
-
Theoretical function:
-
Diminish inflammation around an irritated nerve root
-
Decrease muscle spasm
-
Provide warmth
-
-
Data on efficacy are unclear.
-
May consider initially if severe pain when moving head
-
May aid sleep by limiting motion of the head
-
Try to limit use to <1–2 wks (to avoid weakness and stiffness).
-
Come out of the collar several times per day for range-of-motion (ROM) exercises within limits of pain.
-
-
Physical therapy:
-
May start as pain is improving (within 1–2 wks)
-
Heat/cold, active ROM, isometric strengthening as tolerated
-
As condition improves, ROM and resistive exercises are advanced.
-
May add nonimpact aerobic exercise; gear toward an activity that allows the neck to remain in neutral position (eg, walking, stationary bike).
-
Postural education
-
Ergonomic adjustments
-
-
Traction:
-
Theoretically distracts the vertebra, enlarges the neural foramen, and allows more room for exiting nerves
-
Conflicting reports regarding benefit
-
-
Spinal manipulation (chiropractic treatment):
-
Not routinely recommended
-
No evidence of benefit, and there are reports of complications such as spinal cord and vertebral artery injury.
-
Additional Therapies
Epidural steroid injections:
-
Sometimes used to treat radiculopathy that persist despite NSAIDs, oral steroids, and time
-
A high concentration of steroid is deposited at the site of inflammation.
-
Well-designed studies supporting this treatment are lacking (2)[C]. Have not been shown to change the natural history.
-
Potential side effects:
-
Bleeding
-
Infection
-
Dural puncture
-
Nerve damage
-
Spinal cord and brain stem infarction (4)[C]
-
P.73
Surgery/Other Procedures
-
Consider referring to spine surgeon if:
-
Progressive or severe neurologic deficit
-
Recalcitrant radicular pain or numbness despite nonoperative treatment for 6–12 wks; no data on the optimal timing
-
Instability of the spine with radicular symptoms
-
Moderate to severe myelopathy
-
Muscle atrophy
-
-
Surgical outcomes for relief of arm pain range from 80–90% (2)[C].
-
Typical procedure for cervical radiculopathy:
-
Anterior cervical discectomy and fusion (ACDF): Allows removal of the disk and uncovertebral spur without neural retraction
-
Bone graft or plate is placed anteriorly.
-
-
Total disk arthroplasty (experimental):
-
Diseased disk is removed, and an artificial disk is placed.
-
Allows preservation of motion, thereby theoretically decreasing the incidence of adjacent segment disease (5)[B]
-
Preliminary results have been favorable.
-
No significant complications have been associated with this procedure thus far.
-
Further study is needed.
-
Ongoing Care
Patient Education
In attempt to decrease recurrence of symptoms:
-
Keep the neck muscle strong.
-
Use correct posture when sitting (head centered over shoulders).
-
Workstation setup ergonomically correct
-
Avoid forcing the neck into extremes of motion.
-
Regular aerobic exercise
Prognosis
-
Resolution of all or most symptoms occurs within 6–12 wks in most patients.
-
Acute cervical radiculopathy has up to a 75% rate of spontaneous improvement (2).
Complications
Waiting too long to treat: If weakness is present for too long, patient may never regain full strength and function.
References
1. Radhakrishnan K, Litchy WJ, O'Fallon WM, et al. Epidemiology of cervical radiculopathy. A population-based study from Rochester, Minnesota, 1976 through 1990. Brain. 1994;117 (Pt 2): 325–335.
2. Rhee JM, Yoon T, Riew KD. Cervical radiculopathy. J Am Acad Orthop Surg. 2007;15:486–494.
3. Carette S, Fehlings MG. Clinical practice. Cervical radiculopathy. N Engl J Med. 2005;353:392–399.
4. Malhotra G, Abbasi A, Rhee M. Complications of transforaminal cervical epidural steroid injections. Spine. 2009;34:731–739.
5. Nabhan A, Ahlhelm F, Shariat K, et al. The ProDisc-C prosthesis: clinical and radiological experience 1 year after surgery. Spine. 2007;32:1935–1941.
Additional Reading
Acosta FL, Ames CP. Cervical disc arthroplasty: general introduction. Neurosurg Clin N Am. 2005;16:603–607, vi.
Albright JP, Moses JM, Feldick HG, et al. Nonfatal cervical spine injuries in interscholastic football. JAMA. 1976;236:1243–1245.
Brown S, Guthmann R, Hitchcock K, et al. Clinical inquiries. Which treatments are effective for cervical radiculopathy? J Fam Pract. 2009;58:97–99.
Ellis JL, Gottlieb JE. Return-to-play decisions after cervical spine injuries. Curr Sports Med Rep. 2007;6:56–61.
Young IA, Michener LA, Cleland JA, et al. Manual therapy, exercise, and traction for patients with cervical radiculopathy: a randomized clinical trial. Phys Ther. 2009.
Zmurko MG, Tannoury TY, Tannoury CA, et al. Cervical sprains, disc herniations, minor fractures, and other cervical injuries in the athlete. Clin Sports Med. 2003;22:513–521.
Codes
ICD9
-
722.0 Displacement of cervical intervertebral disc without myelopathy
-
723.4 Brachial neuritis or radiculitis nos
-
839.00 Closed dislocation, cervical vertebra, unspecified
Clinical Pearls
-
Weakness is the most serious effect of cervical radiculopathy and should be followed closely.
-
MRI is the test of choice for imaging the disks and nerves.
-
Treatment in most patients is nonoperative.
-
The timing of surgical intervention for cervical radiculopathy has not been established, but surgery should be considered if there is significant weakness or symptoms that are refractory to nonoperative treatment.
-
Don't miss the red flags: Cervical myelopathy, tumor, infection.