Degenerative changes of the intervertebral discs cause disc-space narrowing, osteophyte formation, and sclerosis of the vertebral body end plates (Figure 4). These changes are easily seen on lateral roentgenograms but are the response of the vertebrae to disc degeneration and so appear after the process is well developed. Therefore, any study based on plain roentgenograms underestimates the prevalence of disc degeneration. Degenerative changes in the zygapophyseal joints include joint-space narrowing, sclerosis, and osteophyte formation; but the changes are not as easily seen or quantified on plain roentgenograms (Figure 5). The joints are paired and located behind the vertebral bodies, so they can only be isolated by oblique views; and even then, one oblique view usually does not show all the joints. For these reasons, little information is available on the frequency of degenerative changes in these joints.
Figure 4. Plain lateral roentgenogram showing end-plate sclerosis, narrowing of the intervertebral disc space, and anterior osteophyte formation.
Figure 5. Plain lateral roentgenogram showing sclerosis, narrowing, and osteophyte formation in the C3-4 zygapophyseal joint.
Degenerative changes of the cervical spine, as seen on plain roentgenograms and more sophisticated imaging studies, are common in both symptomatic and asymptomatic people and are thought to be part of the normal aging process (Figure 6). Degenerative findings are considered to be pathologic when they produce symptoms. However, with the exception of patients with radicular pain, localizing neurologic deficits, and nerve root compression as seen on MRI or CT myelogram studies, the relationship with the patient's neck pain is unclear.
Figure 6. A. Normal, plain lateral roentgenogram of 44-year-old, asymptomatic female. B. Plain lateral roentgenogram of 54-year-old female, indicating degenerative changes of zygapophyseal joints most severe at C4-5 and intervertebral disc degenerative changes at C6-7.
One of the most perplexing clinical challenges is to distinguish the source of a patient's pain when degenerative changes are present. In a review of 200 asymptomatic women, we found that by age 60 to 65, 95% and 70% of women had degenerative changes as seen on plain roentgenograms. Boden found MRI abnormalities of the cervical spine in 19% of 63 asymptomatic volunteers. Fourteen percent occurred in subjects under the age of 40, and 28% in those over 40. Zapletal and colleagues evaluated the atlanto-odontoid joint in 500 consecutive patients who underwent computed tomography of the brain or paranasal sinuses. They found no abnormalities before the fourth decade but thereafter the prevalence increased steadily with age, so that by the ninth decade over 60% had degenerative changes. In a separate article, Zapletal and associates evaluated 355 occipital frontal radiographs of the paranasal sinuses for evidence of osteoarthritis of the lateral C1-C2 joints. Degenerative changes were found ranging from 5.4% in the sixth decade to 18.2% in the ninth. They emphasize that these degenerative changes could be a source of upper neck pain and occipital headaches (Figure 7).
Figure 7. Plain open-mouth roentgenogram showing unilateral degenerative changes at C1-2.
Cite this: The Epidemiology of Neck Pain - Medscape - Sep 01, 1998.