Cervical Discogenic Pain Syndrome Clinical Presentation
- Author: Robert E Windsor, MD, FAAPMR, FAAEM, FAAPM; Chief Editor: Craig C Young, MD more...
Obtaining an accurate history is essential when evaluating patients with neck pain.
- Identifying specific red flags that are indicators of potentially serious spinal or nonspinal pathology or conditions that may interfere with treatment is extremely important. The absence of red flags diminishes the need for special studies during the first 4 weeks of symptoms, a time in which spontaneous recovery is common. Serious spinal and nonspinal conditions associated with red flags include the following:
- Trauma with possible underlying fracture
- Osteoporosis with possible underlying fracture
- Conditions associated with spine instability (eg, rheumatoid arthritis, Down syndrome)
- Significant or progressive neurologic deficit (eg, profound muscle weakness and/or reflex loss, bowel and/or bladder incontinence or retention)
- Vertebral basilar artery insufficiency
- Obtain an accurate description of the characterization of the pain, including location, onset, duration, frequency, description, distribution, and aggravating and relieving factors.
- Differentiating between referred and radicular pain is important. Referred pain is more diffuse, whereas radicular pain is more specifically along the course of a dermatome.
- Patients with disc degeneration could have chronic low-grade pain that is periodically exacerbated for several weeks.
- Cervical discogenic pain may be localized pain, referred pain, or radicular pain.
- Mechanical pain can be constant or intermittent, whereas chemical pain is more likely to be constant.
- Cervicogenic pain is usually worse in positions that involve prolonged sitting, especially in sitting positions with a protruded head posture or prolonged flexion. Bending positions also provoke cervicogenic pain. Frequent changes of position provide relief. However, in cases of severe acute pain, a still position may be most comfortable. Pain worse upon awakening is probably related to using an unsuitable pillow or having adopted an inappropriate posture while sleeping.[2, 20]
- In 1959, Ralph B. Cloward, MD, published referral patterns of the cervical spine discs using cervical discography.
- He found that stimulating the anterolateral aspect of the cervical discs produced pain at the ipsilateral scapula. Stimulation in the midline of the anterior aspect of the disc produced pain between the shoulders in the middle of the back. Cloward described that pain from the C6-7 disc was felt in the inferior angle of the scapula. Pain from the C5-6 disc was felt in the center of the medial scapular border. Pain from C4-5 disc was experienced in the region of the spine and superior angle. Pain from the C3-4 disc was referred to the C7 spinous process and the posterior border of the trapezius muscle.
- Cloward also found that when stimulating patients with posterolateral disc protrusions, the referral patterns were found to be more intense than when stimulating the anterior aspect of the disc and were found to spread from the vertebral border of the scapula out to the shoulder and upper arm as far as the elbow. Midline posterior disc protrusions were found to refer pain to a confined area overlying the fifth cervical to the second thoracic spinous processes near the midline, with upper discs more cephalad and lower discs more caudad. When extensive disc rupture and degeneration were present, a combination of the posterolateral and midline posterior referral patterns was found.
- Risk factors for malignancy include age older than 50 years, history of cancer, unexplained weight loss, pain with bed rest, and failure to improve with conservative therapy.[22, 23]
- Ask questions related to potential infection (eg, history of recent surgery, including dental surgery; history of fever or chills; history of intravenous drug abuse)
- Obtain information regarding the patient's past medical history, including previous neck pain, surgeries, trauma, motor vehicle accidents, and work-related or sports-related injuries.
- Obtain information regarding a history of alcohol, tobacco, or drug use or abuse; osteoporosis; rheumatologic conditions; diabetes; or other conditions associated with neuropathy (eg, vitamin deficiencies, thyroid disease).
- Obtain information regarding previous diagnostic studies and treatment interventions.
Evaluation of Cervical Athletic Injuries
The initial evaluation of cervical spine injuries starts with the basic history and physical examination done on the field. Following this initial evaluation, a more comprehensive evaluation may include plain radiographs; serial examinations; neurologic or orthopaedic consultation; and computed tomography (CT) scanning, MRI, or CT myelogram, or dynamic studies.
See the list below:
- Physical examination of the patient with cervical discogenic pain includes the assessment for neurologic deficits suggestive of myelopathy.
- While assessing the patient, look for altered balance, stooped and wide-base gait, weakness, decreased sensation of the upper extremities, lower motor neuron findings in the upper extremities, and upper motor neuron findings in the lower extremities.
- Patients with a herniated nucleus pulposus (HNP) without radiculopathy can present with limited ROM and referred pain, which may be elicited with the cervical compression test (see image below). Patients with an HNP with radiculopathy may present with limited ROM and radicular pain, dermatomal sensory loss, diminished strength in a myotomal distribution, and loss of muscle stretch reflexes.
- Manual muscle testing has greater specificity than either reflex or sensory changes.[17, 24] The Spurling test can elicit radicular pain and is performed by having the patient actively extend the neck, laterally flex, and rotate toward the side of the pain. Then, careful downward compression is applied on the head. The Spurling test is helpful in the diagnosis of cervical radiculopathy, because of its high specificity. However, its absence does not preclude the diagnosis of radiculopathy because of its low sensitivity.
- The Lhermitte test is performed by flexing the neck with the patient in the sitting position. This test may produce an electriclike sensation down the spine and occasionally the extremities. This electriclike sensation has been reported in patients with cervical spondylosis, cervical myelopathy, cervical cord involvement secondary to tumor, and multiple sclerosis.
- Another helpful clinical sign is pain relief upon arm abduction in cases of a ruptured cervical disc. No changes in pain occur with arm position when the disease process is spondylosis with foraminal stenosis.
- The neck compression test (Spurling test), axial manual traction, and the shoulder abduction test have high specificity but low sensitivity for the diagnosis of root compression in cervical disc disease. Despite the low sensitivity, these tests are valuable in the clinical examination of a patient with neck and arm pain.
- The Arm Squeeze Test may be used to differentiate shoulder pain caused by cervical nerve root compression from that caused by shoulder disease. The test involves squeezing the middle third of the upper arm; if pain is elicited from this maneuver, the etiology of the should pain may be cervical in origin.
See the list below:
- Degenerative changes
- Degenerative changes appear early in the lower cervical spine, with the most severe changes occurring at the C5-6 and C6-7 levels. According to Kramer, this is due to the mechanical influence on the cervical intervertebral discs by the extensive movement carried out in the cervical spine in relation to the rigid thoracic spine. Therefore, the comparative loading per squared centimeter by the head on the cervical discs exceeds that of the thoracic and lumbar spine. Cervical spine degenerative changes appear first in the intervertebral discs during the third, fourth, and fifth decades of life.
- Degenerative disc changes are appreciated by loss of intervertebral disc height and osteophyte development at the origins of the vertebral endplates. These changes lead to loss of shock-absorbing capacity, resulting in abnormal force transmission and increased load to the zygapophyseal joints. Therefore, cervical zygapophyseal joint degenerative changes commonly follow intervertebral disc degeneration.[2, 3] The combination of decreased intervertebral disc space and facet joint degeneration with hypertrophy causes narrowing of the intervertebral foramina, with potential compression of the exiting nerves and associated radicular symptoms.
- Creep is the further detectable movement that occurs after maximal ROM is attained and a constant force is continued on a collagenous structure. Creep is believed to be due to gradual rearrangement of collagen fibers, proteoglycans, and water content in the ligament or capsule being stressed. As the water content of the nucleus pulposus decreases with disc degeneration and aging, the ability to imbibe water and distribute compressive loads also decreases, resulting in increased creep under compression, which can cause incompetence of the annulus. Hickey and Hukins reported that if ligaments were stretched more than 4% of their resting length, irreversible damage would follow.
- As disc degeneration continues, the distinction between the margins of the nucleus and annulus becomes obscured. The negatively charged proteoglycan side chains decrease with subsequent loss of their imbibing capabilities. During this process, the overall collagen content within the disc increases. Primary annular disruption initially may occur in the periphery and is referred to as a rim lesion. As the process continues to progress and the margins of the annulus and nucleus coalesce with infiltration of type III collagen, the gelatinous nucleus becomes replaced and the disc essentially becomes fibrotic.[31, 32, 33, 34]
- Predisposing and precipitating factors for cervical discogenic pain syndrome (CDPS)
- Predisposing and precipitating factors for cervical discogenic pain syndrome (CDPS) include prolonged sitting with poor posture (eg, protruded head posture), frequent of flexion, sudden unexpected movements, and trauma.
- Harms-Ringdahl was able to provoke pain in individuals who were asymptomatic by maintaining a protruded sitting posture. All subjects in the study reported neck pain within 2-15 minutes.
- Static loading with poor sitting or lying postures eventually lead to problems within the cervical spine. Poor posture can also enhance or perpetuate an already existing cervical pain from trauma or whiplash injury.
- Kramer reported that most patients in his practice developed pain for no apparent reason.
- Frequent flexion of the cervical spine is another predisposing factor in the production of symptoms from the cervical spine.
- Sudden unexpected movements, particularly those that involve lateral flexion and rotation of the head and neck with the neck in a protruded position, can cause or precipitate neck pain. Trauma to the cervical spine is commonly seen as a result of whiplash forces occurring during significant motor vehicle accidents or in sports-related cervical spine injuries.
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