Cervical degenerative disorders

1

Define cervical spondylosis. how does this condition present in clinical practice?

Cervical spondylosis is a nonspecific term that refers to age-related degenerative changes within the cervical spinal column. The degenerative process can affect the intervertebral discs, facet joints, uncovertebral joints, and associated soft tissue supporting structures. Often patients with cervical spondylosis have little or no pain. Positive radiographic findings in asymptomatic patients have been reported in approximately 25% of adults under age 40, 50% of adults over age 40, and 85% of adults over age 60. Similarly, abnormal magnetic resonance imaging (MRI) findings in asymptomatic individuals are quite common with disc degeneration reported in more than 25% of adults less than age 40 and 60% of adults older than age 40. Symptomatic patients with cervical spondylosis are often categorized into three clinical syndromes: axial neck pain, cervical radiculopathy, or degenerative cervical myelopathy (see Chapter 13 for details regarding initial evaluation and nonoperative treatment).

2

What is known about the epidemiology, risk factors, and natural history of axial neck pain in adults?

Self-reported neck pain is very common and is experienced by 30%–50% of the adult population annually. The precise location and source of neck pain is often unidentified. Half to three-quarters of patients with neck pain continue to report neck pain 1–5 years later. The prevalence of neck pain peaks during middle age and is higher among women, who are more likely to experience persistent neck pain and less likely to experience pain resolution compared with men. Risk factors for neck pain are multifactorial in nature and include genetic factors, advanced age, female gender, physical activity participation, poor psychological health, tobacco use, history of neck or low back pain, and rear-end automobile accidents. The presence of cervical spinal degeneration on imaging studies is not considered a risk factor for neck pain. The natural history of neck pain in adults is favorable overall, but pain recurrence and chronicity are reported in a substantial number of patients. For patients with acute neck pain, recovery is most rapid in the first 6–12 weeks and gradually slows with little recovery noted after 1 year. Up to 30% of patients with acute neck pain will develop chronic symptoms. Patients with chronic neck pain may experience a stable or fluctuating course with episodes of remission and exacerbation over time.

3

What nonoperative treatments are recommended for chronic axial neck pain?

Patients should be reassessed for red flags (serious underlying conditions) and yellow flags (barriers to recovery) at the time of initial evaluation. Treatment of chronic neck pain is directed toward specific cervical structural pathology, as well as any psychosocial factors that contribute to pain and disability. Evidence-based treatments for chronic neck pain includes active rehabilitation therapy with supervised exercise. Components of an active treatment program include stretching, strengthening with isometric and/or dynamic exercises, cervicothoracic stabilization, and aerobic conditioning. Pharmacologic treatment options include nonsteroidal anti-inflammatory drugs (NSAIDs) or serotonin-norepinephrine reuptake inhibitors (SNRIs) such as duloxetine. Alternatively, a short course (few weeks) of a nonbenzodiazepine muscle relaxant may be considered. Opioid medications are not recommended for treatment of chronic musculoskeletal cervical pain. Alternative therapies supported by randomized controlled evidence include qigong (a holistic system of coordinated body posture and movement) and Iyengar yoga (emphasizes precision and alignment in all postures). Select patients may benefit from cognitive behavioral therapy or a functional restoration program. For patients with presumed zygapophyseal joint pain, diagnosis may be confirmed with nerve blocks performed by anesthetizing the medial branch nerves innervating the target facet joint(s). Anesthetic agents of varying duration of effect are utilized during two separate injection sessions. If the diagnosis is confirmed, percutaneous radiofrequency neurotomy to ablate the medial branch nerves innervating the target facet joint(s) is a treatment option. Although cervical disc degeneration is a cause of neck pain in some patients, distinguishing painful from nonpainful cervical discs remains challenging.

4

How does cervical spondylosis lead to degenerative cervical spinal instability?

Instability is present when the spine is unable to withstand physiologic loads, resulting in significant risk for neurologic injury, progressive deformity, and long-term pain and disability. Cervical degenerative instability presents most commonly as spondylolisthesis. Cervical degenerative instability is less common compared to lumbar instability. Cervical degenerative instability may occur at the C1–C2 level or in the subaxial cervical region.

C1–C2 instability occasionally develops secondary to chronic degeneration involving the atlantodental joint and atlantoaxial joints in association with incompetence of the transverse ligament. Symptoms may include chronic unilateral or bilateral neck pain or pain radiating toward the skull. Retroodontoid ligamentous hypertrophy and pannus formation can lead to symptomatic neural compression. Surgical treatment is instrumented C1–C2 posterior fusion and decompression.

Subaxial cervical instability may develop at a mobile cervical level adjacent to stiff spondylotic segments or between spondylotic segments. Subaxial cervical instability develops most commonly in patients with spondylotic stiffening of middle and lower cervical regions due to compensatory hypermobility at an adjacent mobile segment, most commonly C3–C4 or C4–C5. Cervical degenerative spondylolisthesis presents as neck pain with or without cervical radiculopathy and/or myelopathy. Treatment options include spinal decompression and instrumented fusion through posterior, anterior, or combined approaches. Cervical spinal instability may be diagnosed according to the radiographic criteria of White (>11° angulation, >3.5 mm translation of adjacent subaxial cervical spine segments).

5

When is surgery indicated for chronic neck pain in the absence of radiculopathy or myelopathy?

Indications for surgical treatment of patients with axial neck pain without radicular or myelopathic symptoms are not clearly defined. There is limited evidence in the literature to support anterior cervical discectomy and fusion or cervical disc arthroplasty for this indication. It has been suggested that surgical treatment with single-level anterior cervical fusion be considered after a minimum 1-year course of appropriate nonoperative treatment, in the absence of secondary gain or other factors that could adversely affect outcomes for patients with advanced degenerative changes at one level and relatively normal adjacent levels. The role of cervical discography in this setting remains controversial.

6

What signs and symptoms may be present in a patient with cervical radiculopathy due to a cervical disc herniation?

Cervical radiculopathy most commonly presents with unilateral pain that is most intense in the upper arm below the deltoid insertion and extends below the elbow to involve the thumbs or fingers of the hand according to the specific pattern of dorsal root ganglion or cervical nerve root involvement. Arm pain may be constant and aggravated by neck movement, coughing, or sneezing. Scapular pain is often present. Symptoms are generally worsened by extension of the head or lateral rotation of the head towards the side of the arm pain. Some combination of sensory loss, motor weakness, or impaired reflexes occurs in a dermatomal distribution. Upper cervical radiculopathy may present with occipital pain with radiation. Other symptoms that may occasionally occur include anterior chest pain and headaches.

7

Which nonoperative treatment options are effective for cervical disc herniations?

The majority of patients with cervical radiculopathy improve with nonoperative treatment. Supervised active physical therapy is recommended. Medication options include NSAIDs, SNRIs such as duloxetine, or a short course of oral corticosteroids. Epidural and selective nerve root steroid injections may be considered. Intermittent cervical traction or resting the neck by use of an orthosis, such as a soft collar and reduction of activities, may provide benefit.

8

When is surgery indicated for treatment of a symptomatic cervical disc herniation?

Indications for surgical treatment for a symptomatic cervical disc herniation include intractable radicular symptoms that have not improved with at least 6 weeks of nonoperative treatment, a progressive neurologic deficit, or a neurologic deficit that is associated with significant radicular pain. Neuroimaging studies should correlate with clinical symptoms.

9

What are the options for surgical treatment of a patient with a single-level cervical disc herniation who presents with radiculopathy refractory to nonsurgical treatment?

Surgical treatment options for single-level disc pathology include:

• Posterior foraminotomy with discectomy

• Anterior discectomy and fusion

• Cervical disc arthroplasty

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