CERVICAL SPONDYLOSIS

CERVICAL SPONDYLOSIS

Cervical spondylosis is a chronic degenerative condition of the cervical spine that affects the vertebral bodies and intervertebral disks of the neck (in the form of, for example, disk herniation and spur formation), as well as the contents of the spinal canal (nerve roots and/or spinal cord).

Spondylosis progresses with age and often develops at multiple interspaces.

Chronic cervical degeneration is the most common cause of progressive spinal cord and nerve root compression.

Spondylotic changes can result in stenosis of the spinal canal, lateral recess, and foramina. Spinal canal stenosis can lead to myelopathy, whereas the latter 2 can cause radiculopathy.

PATHOPHYSIOLOGY

Intervertebral disks lose hydration and elasticity with age, and these losses lead to cracks and fissures.

The surrounding ligaments also lose their elastic properties and develop traction spurs. The disk subsequently collapses as a result of biomechanical incompetence, causing the annulus to bulge outward.

As the disk space narrows, the annulus bulges, and the facets override. This change, in turn, increases motion at that spinal segment and further hastens the damage to the disk.

Annulus fissures and herniation may occur. Acute disk herniation may complicate chronic Spondylotic changes.

As the annulus bulges, the cross-sectional area of the canal is narrowed. This effect may be accentuated by hypertrophy of the facet joints (posteriorly) and of the ligamentum flavum, which becomes thick with age.

Neck extension causes the ligaments to fold inward, reducing the anteroposterior (AP) diameter of the spinal canal.

As disk degeneration occurs, the uncinate process overrides and hypertrophies, compromising the ventrolateral portion of the foramen. Likewise, facet hypertrophy decreases the dorsolateral aspect of the foramen. This change contributes to the radiculopathy that is associated with cervical spondylosis.

Marginal osteophytes begin to develop. Additional stresses, such as trauma or long-term heavy use, may exacerbate this process. These osteophytes stabilize the vertebral bodies adjacent to the level of the degenerating disk and increase the weight-bearing surface of the vertebral endplates. 

The result is decreased effective force on each of these structures.

Degeneration of the joint surfaces and ligaments decreases motion and can act as a limiting mechanism against further deterioration. Thickening and ossification of the posterior longitudinal ligament (OPLL) also decreases the diameter of the canal.

The blood supply of the spinal cord is an important anatomic factor in the pathophysiology.

Radicular arteries in the dural sleeves tolerate compression and repetitive minor trauma poorly. The spinal cord and canal size also are factors. A congenitally narrow canal does not necessarily predispose a person to myelopathy, but symptomatic disease rarely develops in individuals with a canal that is larger than 13 mm.

FREQUENCY

Cervical spondylosis is a common condition that is estimated to account for 2% of all hospital admissions. It is the most frequent cause of spinal cord dysfunction in patients older than 55 years.

On the basis of radiologic findings, 90% of men older than 50 years and 90% of women older than 60 years have evidence of degenerative changes in the cervical spine.

Evidence from a 2009 report indicated that cervical spondylosis with myelopathy was the most common primary diagnosis (36%) among elderly US patients admitted to the hospital for surgical treatment of a degenerative cervical spine between 1992 and 2005.

MORTALITY/MORBIDITY

• The course of cervical spondylosis may be slow and prolonged, and patients may either remain asymptomatic or have mild cervical pain.

• Long periods of nonprogressive disability are typical, and in a few cases, the patient's condition progressively deteriorates.

• Morbidity ranges from chronic neck pain, radicular pain, diminished cervical range of motion (ROM), headache, myelopathy leading to weakness, and impaired fine motor coordination to quadriparesis and/or sphincteric dysfunction (eg, difficulty with bowel or bladder control) in advanced cases. The patient may eventually become chair-bound or bedridden.

SEX

Both sexes are affected equally. Cervical spondylosis usually starts earlier in men than in women.

AGE

• Symptoms of cervical spondylosis may appear in persons as young as 30 years but are found most commonly in individuals aged 40-60 years. Radiologic Spondylotic changes increase with patient age; 70% of asymptomatic persons older than 70 years have some form of degenerative change in the cervical spine.

CLINICAL

HISTORY

Common clinical syndromes associated with cervical spondylosis include the following:

• Cervical pain

v  Chronic suboccipital headache may be present. Mechanisms include direct nerve compression; degenerative disk, joint, or ligamentous lesions; and segmental instability.

v  Pain can be perceived locally, or it may radiate to the occiput, shoulder, scapula, or arm.

v  The pain, which is worse when the patient is in certain positions, can interfere with sleep.

• Cervical radiculopathy

v  Compression of the cervical nerve roots leads to ischemic changes that cause sensory dysfunction (eg, radicular pain) and/or motor dysfunction (eg, weakness). Radiculopathy most commonly occurs in persons aged 40-50 years.  

• • An acute herniated disk or chronic spondylitic changes can cause cervical radiculopathy and/or myelopathy

  • The C6 root is the most commonly affected one because of the predominant degeneration at the C5-C6 interspace; the next most common sites are at C7 and C5.

  • Most cases of cervical radiculopathy resolve with conservative management; few require surgical intervention.

• Cervical myelopathy

  • Cervical spondylitic myelopathy is the most serious consequence of cervical intervertebral disk degeneration, especially when it is associated with a narrow cervical vertebral canal.

  • Cervical myelopathy has an insidious onset, which typically becomes apparent in persons aged 50-60 years. Complete reversal is rare once myelopathy occurs.

  • Involvement of the sphincters is unusual at presentation, as based on the patient's perception of symptoms.

  • Five categories of cervical Spondylotic myelopathy are described; these are based on the predominant neurologic findings, as follows:

    • Transverse lesion syndrome - Corticospinal and spinothalamic tracts, as well as the posterior columns, are involved.

    • Motor syndrome - This primarily involves the corticospinal or anterior horn cells.

    • Central cord syndrome - Motor and sensory involvement is greater in the upper extremities than the lower extremities.

    • Brown-Séquard syndrome - Unilateral cord lesion with ipsilateral corticospinal tract involvement and contralateral analgesia are present below the level of the lesion. (See also Brown-Sequard Syndrome, in the Physical Medicine and Rehabilitation section, and Brown-Sequard Syndrome, in the Emergency Medicine section.)

    • Brachialgia and cord syndrome - Predominant upper limb pain is present, with some associated long-tract involvement.

• Less common manifestations

  • Primary sensory loss may be present in a glove like distribution.

  • Tandem spinal stenosis is a simultaneous cervical and lumbar stenosis resulting from spondylosis. It is a triad of findings: neurogenic claudication, complex gait abnormality, and a mixed pattern of upper and lower motor neuron signs.

  • Dysphagia may be present if the spurs are large enough to compress the esophagus.

  • Vertebrobasilar insufficiency and vertigo may be observed.

  • Elevated hemidiaphragm, caused by spondylitic compression of C3-4 (as noted in a case report), may be another finding.

PHYSICAL

Findings at physical examination may include the following:

v Spurling sign - Radicular pain is exacerbated by extension and lateral bending of the neck toward the side of the lesion, causing additional foraminal compromise.

v Lhermitte sign - This generalized electrical shock sensation is associated with neck extension.

v Hoffman sign - Reflex contraction of the thumb and index finger occurs in response to nipping of the middle finger. This sign is evidence of an upper motor neuron lesion. A Hoffman sign may be insignificant if present bilaterally.

v Distal weakness

v Decreased ROM in the cervical spine, especially with neck extension

v Hand clumsiness

v Loss of sensation

v Increased reflexes in the lower extremities and in the upper extremities below the level of the lesion

v A characteristically broad-based, stooped, and spastic gait

v Extensor planter reflex in severe myelopathy

CAUSES

• Age

  • Cervical spondylosis is a disease observed most commonly in elderly individuals.

  • Among persons younger than 40 years, 25% have degenerative disk disease (DDD), and 4% have foraminal stenosis, as confirmed with magnetic resonance imaging (MRI).

  • In persons older than 40 years, almost 60% have DDD, and 20% have foraminal stenosis, as confirmed with MRI.

• Trauma

  • The role of trauma in spondylosis is controversial.

  • Repetitive, subclinical trauma probably influences the onset and rate of progression of spondylosis.

• Work activity - Cervical spondylosis is significantly higher in patients who carry loads on their head than in those who do not.

• Genetics

  • The role of genetics is unclear.

  • Patients older than 50 years who have normal cervical spine radiographic findings are significantly more likely to have a sibling with normal or mildly abnormal radiographic results.

DIAGNOSIS

LABORATORY STUDIES

• Usually, no specific findings are present.

• Other findings may include those related to an underlying etiologic or pathogenetic disorder that initiates the spondylitic changes.

IMAGING STUDIES

• Plain cervical radiography is routine in every patient with suspected cervical spondylosis.

  • This examination is valuable in evaluating the uncovertebral and facet joints, the foramen, intervertebral disk spaces, and osteophyte formation.

  • In select circumstances, flexion-extension views may be needed to detect instability.

• Myelography, with computed tomography (CT) scanning, is usually the imaging test of choice to assess spinal and foraminal stenosis.

  • Because myelography method is invasive, most physicians depend on MRI in diagnosing cervical spondylosis.

  • Myelography adds anatomic information in evaluating spondylosis.

  • Myelography may be especially useful in visualizing the nerve root takeoff.

  • CT scanning, with or without intrathecal dye, can be used to estimate the diameter of the canal.

  • CT scans may demonstrate small, lateral osteophytes and calcific opacities in the middle of the vertebral body.

• MRI is a considerable advance in the use of imaging to diagnose cervical spondylosis. It offers the following advantages:

  • Direct imaging in multiple planes

  • Better definition of neural elements

  • Increased accuracy in evaluating intrinsic spinal cord diseases

  • Noninvasiveness

  • Myelogram like images

• High – signal-intensity lesions can be seen on magnetic resonance images of spinal cord compression; this finding indicates a poor prognosis.

OTHER TESTS

• Electromyography is useful in evaluating radiculopathy caused by spondylosis, but it may have only limited value in assessing myelopathy.

• In myelopathy, Somatosensory evoked potential (SSEP) responses are delayed or have a low amplitude.

• Cortical motor evoked potentials (MEP) may be more sensitive than SSEPs in evaluating spinal cord dysfunction.

• As an invasive procedure, cervical discography is not commonly used in the evaluation of cervical spondylosis.

• Urodynamic studies may be helpful in evaluating bladder incontinence.

HISTOLOGIC FINDINGS

Thinning and fragmentation of the articular cartilage may be observed. The normal smooth, white articular surface becomes irregular and yellow. Continued loss of articular cartilage leads to exposure of areas of subchondral bone, which appear as shiny foci on the articular surface (eburnation).

Fibrosis, increased bone formation, and cystic changes frequently occur in the underlying bone. Loss of articular cartilage stimulates new bone formation, usually in the form of nodules (osteophytes) at the bone edges.

TREATMENT

PHYSICAL THERAPY

v Immobilization of the cervical spine is the mainstay of conservative treatment for patients with cervical spondylosis. Immobilization limits the motion of the neck, thereby reducing nerve irritation. Soft cervical collars are recommended for daytime use only, but they are unable to appreciably limit the motion of the cervical spine.

More rigid orthoses (eg, Philadelphia collar, Minerva body jacket) can significantly immobilize the cervical spine. The patient's tolerance and compliance are considerations when any of the braces are used.

A program of isometric cervical exercises may help to limit the loss of muscle tone that results from the use of more restrictive orthoses. Molded cervical pillows can better align the spine during sleep and provide symptomatic relief for some patients.

v Mechanical traction is a widely used technique. This form of treatment may be useful because it promotes immobilization of the cervical region and widens the foraminal openings.

v The use of cervical exercises has been advocated in patients with cervical spondylosis. Isometric exercises are often beneficial to maintain the strength of the neck muscles. Neck and upper back stretching exercises, as well as light aerobic activities, also are recommended.

v Passive modalities generally involve the application of heat to the tissues in the cervical region, either by means of superficial devices (eg, moist-heat packs) or mechanisms for deep-heat transfer (eg, ultrasound, diathermy).

v Manual therapy, such as massage, mobilization, and manipulation, may provide further relief for patients with cervical spondylosis. Mobilization is performed by a physical therapist and is characterized by the application of gentle pressure within or at the limits of normal motion, with the goal of increasing the ROM.

Manual traction may be better tolerated than mechanical traction in some patients. Manipulation is characterized by a high-velocity thrust, which is often delivered at or near the limit of the ROM. The intention is to increase articular mobility or to realign the spine.

Contraindications to manipulative therapy include myelopathy, severe degenerative changes, fracture or dislocation, infection, malignancy, ligamentous instability, and vertebrobasilar insufficiency.

OCCUPATIONAL THERAPY

Patients with upper extremity weakness often lose their ability to perform activities of daily living (ADL), vocational activities, or recreational activities.

Lifestyle modifications may involve an evaluation of workplace ergonomics, postural training, neck-school therapy (supervised, small-group therapy), stress management, and vocational assistance.

Disability can be improved with specific strengthening exercises of the upper extremities, special splinting to compensate for weakness, and the use of assistive devices that allow the patient to perform previously impossible activities.

RECREATIONAL THERAPY

The recreational therapist can use recreational and community activity to accomplish the following:

• Help the patient maintain his/her physical strength, social skills, and motivation

• Assist the patient and family in adjusting to the disability

• Decrease the patient's atypical behaviors

• Increase the patient's independence

• Reinforce other therapies

• Provide community integration

• Further evaluate the level of functioning in cases of severe disability caused by cervical spondylosis

SURGICAL INTERVENTION

• Indications for surgery include the following:

  • Progressive neurologic deficits

  • Documented compression of the cervical nerve root and/or spinal cord

  • Intractable pain

• The aims of surgery are to relieve pain and neuronal structure compression, as well as, in select cases, to achieve stabilization.

• Approaches for surgery are anterior or posterior.

  • Anterior approaches include the following:

    • Discectomy without bone graft

    • Discectomy with bone graft

    • Cervical instrumentation

  • Posterior approaches include the following :

    • Decompressive laminectomy and foraminotomy

    • Hemilaminectomy

    • Laminoplasty

OTHER TREATMENT

Ø  Injection - Cervical, zygapophyseal, intra-articular steroid injection can be helpful for active synovitis. The facet injections can be diagnostic and therapeutic. Mechanical facet pain is better evaluated with facet joint nerve blocks.

Long-term relief can often be accomplished with a rhizotomy procedure. Cervical epidural block might be beneficial in cervical spondylosis, especially if an inflammatory component is present. Epidural and selective nerve root blocks can be diagnostically and therapeutically helpful in cases of radiculopathy. Trigger-point injections may be helpful.

Ø  Treatment of bowel and bladder dysfunction - Some patients with bowel dysfunction may benefit from a daily suppository, enema, or oral laxative. The administration should be followed by digital stimulation so that the patient's defecation occurs at a predictable time. Evaluate bladder incontinence with urodynamic studies.

Pharmacologic intervention is possible in some patients, but many individuals need an intermittent catheterization program and control of fluid intake. An indwelling catheter is occasionally required if the patient does not have the dexterity to comply with a catheter program.

Ø  Rehabilitative nursing - A nurse should be involved in the educational process regarding the development of an effective bowel and/or bladder program and the prevention of pressure sores.

Ø  Psychosocial support - Patients with significant disability often react with fear, anxiety, or depression. Referral to a psychologist or psychiatrist for psychotherapy, pharmacotherapy, and/or family counseling may be indicated.

MEDICATION

The goal of pharmacotherapy is to reduce morbidity and prevent complications.

NONSTEROIDAL ANTI-INFLAMMATORY DRUGS

NAPROXEN (Anaprox, Naprelan, Naprosyn, Aleve)

Relieves mild to moderately severe pain and inhibits inflammatory reactions, probably by decreasing the activity of the enzyme cyclooxygenase, thus inhibiting prostaglandin synthesis.

Adult: 250-500 mg PO bid; may increase to 1.5 g/d for limited periods; generally, not to exceed 1.25 g/d

Pregnancy

B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals

D - Fetal risk shown in humans; use only if benefits outweigh risk to fetus

Precautions

Acute renal insufficiency, interstitial nephritis, hyperkalemia, hyponatremia, and renal papillary necrosis may occur; patients with pre-existing renal disease or compromised renal perfusion risk acute renal failure; leukopenia occurs rarely, is transient, and usually returns to normal during therapy; persistent leukopenia, granulocytopenia, or thrombocytopenia warrants further evaluation and may require discontinuation of drug

IBUPROFEN (Ibuprin, Advil, Motrin)

NSAID from propionic acid derivatives group. Effective inhibitor of cyclo-oxygenase, which is responsible for biosynthesis of prostaglandins. Rapidly absorbed after oral administration. Half-life in plasma is about 2 h.

Ibuprofen passes slowly into the synovial spaces and may remain there in higher concentration as the concentration in plasma declines. Excretion is rapid and complete (mainly excreted in urine as metabolites or conjugates).

Adult: 1200-1800 mg PO divided q4-6h; not to exceed 3200 mg in divided doses 

Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus

D - Fetal risk shown in humans; use only if benefits outweigh risk to fetus

Precautions

Caution in congestive heart failure, hypertension, and decreased renal and hepatic function; discontinue if clinical symptoms and signs of liver disease develop or if abnormal liver test results persist; caution in anticoagulation abnormalities or during anticoagulant therapy; GI adverse effects may occur; common adverse side effects include thrombocytopenia, skin rashes, headache, dizziness, and blurred vision, as well as (in a few cases) toxic amblyopia

INDOMETHACIN (Indocin, Indochron E-R)

Rapidly absorbed; metabolism occurs in the liver by demethylation, deacetylation, and glucuronide conjugation. Indomethacin inhibits prostaglandin synthesis.

Adult: 25-50 mg PO bid/tid

75 mg SR PO bid; not to exceed 200 mg/d 

Pregnancy

B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals

D - Fetal risk shown in humans; use only if benefits outweigh risk to fetus

Precautions

Acute renal insufficiency, hyperkalemia, hyponatremia, interstitial nephritis, and renal papillary necrosis may occur; increases risk of acute renal failure in patients with pre-existing renal disease or compromised renal perfusion; reversible leukopenia may occur (discontinue if there is persistent leukopenia, granulocytopenia, or thrombocytopenia)

MEFENAMIC ACID (Ponstel)

Inhibits inflammatory reactions and pain by decreasing prostaglandin synthesis.

Adult: 500 mg PO initially, followed by 250 mg q4h prn 

Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus

D - Fetal risk shown in humans; use only if benefits outweigh risk to fetus

Precautions

May have adverse effects in fetus; caution in congestive heart failure, hypertension, and decreased renal and hepatic function; caution in anticoagulation abnormalities or during anticoagulant therapy

PIROXICAM (Feldene)

Decreases the activity of cyclooxygenase, which in turn inhibits prostaglandin synthesis; piroxicam's effects decrease the formation of inflammatory mediators.

Adult: 10-20 mg/d PO qd 

Pregnancy

B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals

D - Fetal risk shown in humans; use only if benefits outweigh risk to fetus

Precautions

Acute renal insufficiency, hyperkalemia, hyponatremia, interstitial nephritis, and renal papillary necrosis may occur; increases risk of acute renal failure in patients with pre-existing renal disease or compromised renal perfusion; reversible leukopenia may occur (discontinue if there is persistent leukopenia, granulocytopenia, or thrombocytopenia)

ASPIRIN (Anacin, Ascriptin, Bayer Aspirin)

Treats mild to moderately severe pain and headache. The drug inhibits prostaglandin synthesis, which prevents the formation of platelet-aggregating thromboxane A2; aspirin acts on the heat-regulating center of the hypothalamus and vasodilates peripheral vessels to reduce fever.

By inhibiting prostaglandin synthesis, aspirin may also inhibit key steps in the inflammation process.

Adult: 90-100 mg/kg/d PO divided q6-8h for 2 wk initially, then 60-70 mg/kg/d for 6 wk; not to exceed 3.6-5.4 g/d 

CORTICOSTEROIDS

Corticosteroids have potent anti-inflammatory properties. These medications can be given orally or as a single intramuscular (IM) injection.

PREDNISONE (Deltasone, Orasone, Sterapred)

Glucocorticoid steroid used to treat a variety of inflammatory conditions. Prednisone may decrease inflammation by reversing increased capillary permeability and suppressing PMN activity.

Dosages may be adjusted for individual sensitivities and associated medical conditions.

Adult: <60 years: 5-200 mg/d PO qd or in divided doses; not to exceed 200 mg/d; adjust to lowest effective dose once desired response achieved

>60 years: Reduced dose may be necessary

MUSCLE RELAXANTS

Muscle relaxants are used to treat muscle spasm, which may play a role in patient discomfort.

METHOCARBAMOL (Robaxin)

Skeletal muscle relaxant used in conjunction with other therapies to treat pain and discomfort associated with musculoskeletal conditions. Reduces nerve impulse transmission from spinal cord to skeletal muscle.

Adult: <60 years: 1.5 g PO qid for first 48-72 h; not to exceed 6 or 8 g/d in severe conditions; usual maintenance dose is 750 mg to 1 g PO qid or 1.5 g tid

>60 years: Reduced dose may be necessary

Maintenance dose: 800 mg (2 tabs) PO qid 

Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus

Precautions

Caution in history of seizures; take with food; adverse effects include lightheadedness, blurred vision, dizziness, drowsiness (patient should avoid performing dangerous tasks while on medication), itching, conjunctivitis, fever, headache, hives, nasal congestion, nausea or vomiting, rash, urticaria (ie, itching attack, possibly as a result of drug sensitivity), extreme weakness, temporary vision loss, and transient paralysis; overdose symptoms include, convulsions, vomiting, diarrhea, headache, nausea, difficult breathing, sensation of paralysis, and coma; may cause color interference in certain screening tests for 5-hydroxyindoleacetic acid (5-HIAA) and vanillylmandelic acid (VMA); patient should avoid drinking alcoholic beverages or taking other CNS depressants, because of the potential for additive CNS depression (excessive sleepiness, slurred speech, decreased awareness); caution in impaired liver or kidney function; adverse effects likely in patients >60 y; avoid use while breastfeeding (potential risk to newborn); prolonged use requires monitoring

ANTIDEPRESSANTS

These agents are useful in select cases of chronic pain.

AMITRIPTYLINE (Elavil)

Amitriptyline is an antidepressant with sedative effects. The mechanism of action is unknown. Amitriptyline is not an MAOI and does not act primarily by stimulating CNS.

Adult: Outpatients: 75 mg PO qd in divided doses; not to exceed 150 mg/d; therapeutic effect may take as long as 30 d to develop

Hospitalized patients: May require 100 mg/d PO; may gradually increase up to 300 mg/d

Adolescents and elderly patients: Lower doses recommended; 10 mg PO tid with 20 mg hs may be satisfactory if higher dosages not tolerated.