Low back pain alone accounts for approximately 3% of all ED visits in the United States.¹ Nearly one third of ED back pain patients receive x-rays, and 10% undergo CT or MRI imaging.² Analysis of the 2010 Global Burden of Disease study reveals a point prevalence of 5% for low back pain and 9% for neck pain. Back pain is the number one cause of disability in the United States; neck pain is number four.^3,4

RISK FACTORS FOR SERIOUS CAUSES OF NECK AND BACK PAIN

There are many causes of neck and back pain, including trauma and biomechanical injuries, degeneration, inflammation (arthritides), infection (e.g., discitis, meningitis, and epidural abscess), infiltration (e.g., metastatic cancer and spinal cord tumors), and compression (e.g., epidural hematoma and abscess). In many cases of atraumatic neck and back pain, no specific cause can be identified. However, due to the high volume of ED patients with neck and back pain, clinicians can develop an indifference to this complaint and potentially overlook serious causes. Take care to perform a systematic evaluation based on risk factors in the history and physical examination, and let findings guide diagnostic testing and management (Table 279-1). Consider spinal anatomy while focusing on the presence or absence of neurologic signs to identify pathologic causes and prevent complications.

Radiculopathy and myelopathy are identified through pattern recognition of the motor and dermatome innervations and their associated spinal level (see Figure 164-1 and Tables 164-1 and 164-2 in chapter titled “Neurologic Examination”).

In general, it is helpful to classify patients with neck pain into two groups: those with uncomplicated neck pain arising mainly from the joints and associated ligaments and muscles of the neck, and those with neck pain and radiculopathy (signs and symptoms attribuTable to a single nerve root) and/or myelopathy (signs or symptoms due to a spinal cord lesion, stenosis, or compression).

HISTORY IN PATIENTS WITH NECK PAIN

Ask about the onset, duration, and location of the neck pain; recent or remote trauma; associated symptoms; stiffness; deformity; neurologic complaints (e.g., weakness, changes in sensation, gait, or vision); constitutional symptoms such as fever, anorexia, and weight loss; and comorbid conditions such as arthritis, cancer, and infections. See Table 279-1 for clues to serious pathology to investigate in the history. Rheumatoid arthritis, ankylosing spondylitis, and psoriatic spondyloarthropathy may involve the C1-C2 joint, damage the transverse ligament, and erode the odontoid process, yielding instability of the atlantoaxial joint. Subluxation may occur spontaneously or following a trivial injury. Morning stiffness may signify arthritic joints. Identify precipitating and palliative factors, maneuvers, or activities. Inquire about prior episodes of neck pain, past diagnostic studies, and treatment. Determine the character of pain and its distribution. Patients with radiculopathy often complain of sharp, burning, intense pain that radiates to the trapezius, periscapular area, or down the arm. Weakness or paresthesias may develop weeks after pain onset. Patients with myelopathy may have neck pain that progresses insidiously and may complain of clumsy hands, gait disturbances, and sexual or bladder dysfunction. Table 279-2 summarizes important differences in symptoms between uncomplicated mechanical neck pain and neck pain associated with radiculopathy or myelopathy.

PHYSICAL EXAMINATION IN PATIENTS WITH NECK PAIN

Begin with a general assessment of the patient, noting evidence of weight loss, pallor, adenopathy, and abnormalities of posture, movement, and facial expression.⁵ Pain may cause splinting of the head on the shoulders during position change. Assess active and passive movement, including rotation (chin to shoulder), lateral flexion (ear to shoulder), and flexion-extension (chin down, then up). Most mechanical causes of neck pain result in asymmetric lesions and asymmetrically limited or painful movements, whereas inflammatory or neoplastic disorders are typically more widespread, with pain and movement restriction being more symmetric.⁵ When localized ipsilateral neck pain is felt toward the side of head movement, suspect facet (zygapophyseal) joint irritability. Examine for Spurling’s sign (see Table 279-2). The abduction relief sign, performed by having the patient place the hand of the affected upper extremity on the top of his or her head to obtain relief, may indicate soft disk protrusion causing radicular pain. When neck pain occurs on the side away from head movement, suspect a ligamentous or muscular source.

Palpate the posterior cervical triangle, the supraclavicular fossa, carotid sheaths, and the anterior neck. C5-C6 root lesions often elicit tenderness over the brachial plexus at Erb’s point, 2 to 3 cm above the clavicle, midway up the posterior border of the sternocleidomastoid muscle in the posterior triangle of the neck. A C8-T1 root lesion may cause tenderness over the ulnar nerve at the elbow.

Pathology in the lymph nodes, salivary glands, or thyroid gland may cause neck pain. A bruit over the carotid may signal cerebral insufficiency; a bruit over the subclavian arteries may be associated with thoracic outlet or vascular steal syndrome. Examine the temporal artery for tenderness, because temporal arteritis may be the cause of neck and shoulder pain (see also chapter 165, “Headache”).

Sensory symptoms of pain or dysesthesias are difficult to evaluate, particularly when motor signs are absent, which is often the case in cervical spinal radiculopathies. The discrete separation of the motor and sensory roots at the cervical neural foramina can explain motor sparing despite severe sensory symptoms. For example, C7 root irritability without motor weakness can present as aching at the medial to middle scapular border; aching in the myotome distribution to the chest, axilla, or triceps; or numbness or tingling in the middle finger.

Early detection of cervical spinal myelopathies requires a complete neurologic examination. Hyperreflexia, a positive Babinski’s sign, clonus, gait disturbance, sexual or bladder dysfunction, lower extremity weakness, impaired fine hand movement, and upper and lower extremity spasticity may signal myelopathy. Examine for Lhermitte’s sign (Table 279-2), which is indicative of possible cord compression. Hoffman’s sign indicates an upper motor neuron lesion and is performed by flicking the tip of the middle finger as the hand is relaxed in a neutral position. A positive (abnormal) response is flexion of the thumb and index finger in a pinching motion.

Table 279-3 summarizes the sensory, motor, and reflex findings in cervical radiculopathy. This information should be used to determine the level of motor and sensory involvement and to compare findings in the affected and unaffected sides. Bilateral or multilevel involvement usually implies serious pathology.

Laboratory testing is rarely helpful, unless considering infection. See the “Epidural Compression Syndrome,” “Transverse Myelitis,” and “Spinal Infection” sections later in this chapter, as well as chapter 246, “Neck and Upper Airway.”

The need for imaging studies depends on the clinical condition suspected and the duration of neck pain. Acute (days to weeks), uncomplicated, nonradicular, nonmyelopathic, atraumatic neck pain typically requires no imaging because the cause is likely benign and the treatment is conservative.⁵ Obtain three-view cervical spine films in patients with chronic (weeks to months) neck pain with or without a history of trauma, those with neck pain and a prior history of malignancy or remote neck surgery,⁵ and those with neck pain and preexisting spinal disorders such as rheumatoid arthritis, ankylosing spondylitis, and psoriatic spondyloarthropathy. Flexion-extension films may be useful if instability is suspected, especially in patients with rheumatoid arthritis or other inflammatory arthritides.⁶ Patients with normal radiographs, patients with radiographic evidence of degenerative changes without neck instability, or patients with radiographic evidence of previous trauma and no neurologic signs or symptoms require no further imaging.⁵ MRI is indicated for patients with chronic neck pain with neurologic signs or symptoms regardless of the plain radiographic findings.⁵ MRI is also indicated when plain radiographs reveal bone or disk margin destruction, if there is cervical instability, and (with intravenous contrast) if epidural abscess or malignancy is suspected.⁵ CT myelography is recommended when contraindications to MRI exist.

DIFFERENTIAL DIAGNOSES OF NECK PAIN

Mechanical Neck Disorders

Mechanical neck disorders are also called hyperextension strain, acceleration-deceleration injury, hyperextension-hyperflexion injury, neck strain, neck sprain, and whiplash. The most common precipitating events are motor vehicle collisions, falls, sports injuries, and work-related injuries (see chapter 258, “Spine Trauma” for discussion of acute injury). Strain injury, caused by an awkward position during sleep or prolonged abnormal head-neck positions during work or recreation, is another cause.

Cervical Disk Herniations

Cervical disk herniations occur as the nucleus pulposus protrudes through the posterior annulus fibrosis, producing an acute radiculopathy or, occasionally, a myelopathy. Protrusions are usually confined by the posterior longitudinal ligament but can occasionally extrude through this ligament as free fragments. Direct posterior ruptures, although infrequent, can produce progressive myelopathy, whereas the more common posterolateral herniations can cause acute cervical radiculopathy. The levels of most frequent involvement are C5-C6 (C6 root) and C6-C7 (C7 root).

The symptoms of an acute cervical disk prolapse include neck pain, headache, pain distributed to the shoulder and along the medial scapular border, dermatome pain, and dysesthesia in the spinal root distribution to the shoulder and arm. Motor signs include fasciculations, atrophy and weakness in the dermatome distribution of the spinal root, loss of deep tendon reflexes, and, with cervical myelopathy, lower extremity hyperreflexia, Babinski’s sign, and in rare cases, loss of sphincter control. Cervical hyperextension and lateral flexion to the symptomatic side (Spurling’s sign; see Table 279-2) may replicate the symptoms, as can a Valsalva maneuver, whereas manual cervical distraction in flexion alleviates them. A thorough physical examination, including strength, sensory, and reflex testing, may delineate the level of root involvement (see Table 279-3). MRI is necessary for diagnosis.

Cervical Spondylosis and Stenosis

Cervical spondylosis (or degenerative disk disease or osteoarthritis) is a progressive, degenerative condition resulting in a loss of cervical flexibility, neck pain, occipital neuralgia, radicular pain, or occasionally progressive myelopathy. There is progressive degeneration of the disks, ligaments, facet joints (zygapophyseal joints), and uncovertebral joints (joints of Luschka). From a radiographic standpoint, cervical spondylosis may be diagnosed if any one of three findings is present: osteophytes, disk space narrowing, or facet disease. However, there is a high prevalence of cervical spondylosis in asymptomatic individuals, and care must be taken in ascribing painful syndromes to findings on imaging. Degenerative disk disease predisposes a patient to progressive osteoarthrosis of the cervical spine, joint instability, and incongruous joint motion during neck movement. Spondylosis most commonly occurs at the C5-C6 and C6-C7 levels.

Osteophytic spurs can encroach posteriorly on the spinal canal, producing cervical myelopathy; laterally on the intervertebral foramen, producing cervical radiculopathy; and anteriorly on the esophagus, producing dysphagia. Spurious osteophytes may also produce Horner’s syndrome, vertebrobasilar symptoms, severe radicular symptoms without associated neck pain, painless upper extremity myotome weakness, and chest pain mimicking angina. Neurologic findings (radiculopathy or myelopathy) may be gradual in onset unless there is a history of recent trauma.

The combination of a congenitally narrowed spinal canal, further compromised by a vertebral osteophytic bar anteriorly and a buckling ligamentum flavum posteriorly, increases the risk of myelopathy secondary to cervical spinal stenosis as the diameter of the spinal canal is reduced to less than 13 mm.

Cancer of the Cervical Spine

Consider metastatic cancer in the differential diagnosis of chronic neck pain, especially unremitting night pain. Lung, breast, and prostate cancers and lymphoma and multiple myeloma may involve the cervical spine. Although most cases of epidural cord compression occur in the thoracic spine, involvement of the cervical spine and multiple levels are not unusual. Myelopathy, which is commonly caused by disk or degenerative disease, is rarely caused by metastatic tumors. Plain films have inadequate sensitivity (10% to 17% false-negative rate) in detecting spinal metastases but may reveal destruction of the vertebral bodies, lytic lesions of the pedicles, and pathologic compression fractures. MRI is the standard for the detection of spinal epidural metastatic disease and cord compression, and cancer patients with radiographic evidence of bone or disk margin destruction should undergo MRI.⁵

Cervical Myofascial Pain Syndrome

Myofascial pain syndrome is a cause of chronic neck pain and is often confused with radiculopathy. Myofascial pain symptoms may present or exacerbate acutely, especially after trauma. Psychological distress and specific personality traits are risk factors. Typically, patients complain of pain in the neck, scapula, and shoulder with or without nondermatomal radiation into the upper extremity. Tender spots, “trigger points,” may be evident on palpation of the head, neck, shoulder, and scapular region. Neurologic examination is normal. Because radiographic cervical spine abnormalities develop with age in the asymptomatic population, radiographic findings cannot be relied upon to verify the source of neck pain or upper extremity symptoms. Imaging reveals either nonspecific degenerative or disk changes that do not correlate with the clinically suspected site.

Other Conditions

Epidural abscess, osteomyelitis, and transverse myelitis are infectious and inflammatory causes of neck pain (see related sections later in this chapter). Cervical spinal epidural hematoma often presents as neck pain followed by symptoms and signs of cord compression (see later section on epidural compression syndrome) and should be considered in the patient taking anticoagulants or in the patient with a bleeding diathesis. Pain from ischemic heart disease may radiate into the neck and shoulder. Peripheral nerve involvement, such as carpal tunnel syndrome, may present as a C6-C7 sensory radiculopathy, whereas multiple sclerosis, amyotrophic lateral sclerosis, subacute combined degeneration, and syrinx are in the differential of myelopathy.

Treatment issues can be divided into three categories: neck pain, neck and arm pain consistent with radiculopathy, and myelopathy. There is little evidence-based science to support many of the commonly recommended conservative treatment modalities (e.g., physiotherapy, acupuncture, electrotherapy, manipulation, traction, thermotherapy, medicinal and injection therapies, exercises).^7,8,9,10,11 Individual patients may indeed benefit from one or more of these therapies.

TREATMENT OF UNCOMPLICATED NECK PAIN

Most cases of neck pain without clear underlying pathology will improve with minimal intervention. The patient should be advised to “act as usual” and avoid activities that produce pain. Initial medications may include nonsteroidal anti-inflammatory drugs (NSAIDs), muscle relaxants, and for significant pain, a short course of oral opiates; no NSAID, muscle relaxant, or opiate is clearly superior to another in its class. Encourage follow-up with the primary physician to assess the need for physical or manual therapies or additional medications.

Patients with acute neck pain following an acceleration-deceleration (whiplash) injury may benefit from a similar pharmacologic regimen as that described earlier. In a Danish study of 458 patients, immobilization with a semi-rigid collar, advice to “act as usual,” and active mobilization had similar effects in terms of preventing long-lasting pain and disability.¹² A soft collar reduces range of motion of the neck less than 20% and provides little immobilization or neck support.¹³ If a soft collar is given, it should be used for no more than 10 days. Spinal manipulation therapy or home exercises after two 60-minute physical therapy sessions may each be more effective than medication therapy for short- and long-term pain relief.¹⁴

Therapy for neck pain from myofascial pain syndrome should address both muscular tension and psychobehavioral issues. See chapter 38, “Chronic Pain” for further discussion including recommendations for alternative therapies.

TREATMENT OF CERVICAL RADICULOPATHY