Age-Related Prevalence of Facet-Joint Involvement in Chronic Neck and Low Back Pain
From: Pain Physician 2008; 11:1:67-75
Background: Spinal pain is common in all age groups. While the research has focused primarily on incidence and prevalence in younger working adults, there is evidence that spinal pain is one of the most frequent complaints in older persons and is
responsible for functional limitations. While facet arthrosis is a common radiographic finding, which has been suggested to be a potential cause of spinal pain, nearly 10% of all adults show signs of degeneration by the time they reach age 30. Radiographic
changes of osteoarthritis have been shown to be equally common in patients with and without low back or neck pain. The studies of low back pain have shown the prevalence of facet joint involvement to be approximately 15% to 45%. However, age related prevalence of facet joint neck pain has not been studied.
Objective: To assess age-related prevalence and false-positive rates of facet joint involvement in chronic spinal pain using controlled comparative local anesthetic blocks.
Design: Retrospective analysis of 424 patients, divided into 6 groups based upon age (Group I: aged 18 – 30 years, Group II: aged 31 – 40 years, Group III: aged 41 – 50 years, Group IV: aged 51 – 60, Group V: 61 – 70 years, and Group VI: greater than 70 years of age).
Results: The prevalence of cervical facet joint-related pain was the lowest (33%) in Group VI and highest (42%) in Group I. False-positive rates for cervical facet joint blocks ranged from 39% (Group III) to 58% (Group V) with an overall false-positive rate of 45%. The prevalence of facet joint involvement in lumbar spinal pain ranged from 18% (in Group II) to 44% (in Group IV), with significant differences noted when Group II and Group III were compared to other groups and with higher rates in Group V.
Conclusion: This study demonstrated a variable age-related prevalence of facet joint pain in chronic low back pain, whereas in the cervical spine it was similar among all the age groups.
The present study demonstrated the prevalence of facet joint involvement in chronic low back pain variable from 18% (Group II aged 31 – 40 years) to 44% (Group IV aged 51 – 60 years). Despite this variance, these differences were not significant, and there were no other significant differences in the prevalence of facet joint involvement between age groups of patients. False-positive rates varied from a low of 30% to a high of 64% (Group V). The prevalence of facet joint involvement in chronic neck pain ranged from 33% (Group VI) to 42% (Group I), and false-positive rates ranged from 39% (Group III) to 58% (Group V).
Overall, despite minor variations, this study showed a lack of correlation between age and the prevalence of facet-joint involvement in either cervical or lumbar pain.
Discussion: The lifetime prevalence of spinal pain has been reported to be between 54% and 80%. Although research has primarily focused on incidence and prevalence in younger, working adults, there is evidence that back pain, 1) is one of the most frequent complaints in older persons, 2) is responsible for functional limitations, 3) causes difficulty in performing daily life activities, and 4) is also a risk factor for future disability. The published literature commonly states that 80% to 90% of low back pain resolves in about 6 weeks, irrespective of the administration or type of treatment, with only 5% to 10% of patients developing persistent back pain. Contrary to this assumption, actual analysis of research evidence shows that chronic low back and neck pain persist 1 year or longer in 25% to 60% of adult and/or elderly patients.
Based on evaluations utilizing controlled diagnostic blocks, the prevalence of zygapophysial or facet joint involvement has been estimated to be between 15% to 45% in heterogeneous groups of patients with chronic low back pain and 36% to 67% in patients with chronic neck pain. However, false-positive rates varying from 27% to 63% in the cervical spine and 17% to 50% in the lumbar spine have also been described.
Facet arthrosis, a common radiographic finding, has long been suggested to be a potential cause of low back pain. The exact pain generator within the facet joint remains poorly defined. Studies have shown that facet arthrosis frequently appears early in the third decade, and is often related to the amount of heavy work done before the age of 20. Eubanks et al found evidence that nearly 60% of all adults show some signs of degenerative changes by the time they reach age 30. As well, it was shown that following the initiation of arthritic changes, subsequent degeneration appears to steadily increase until the seventh decade, by which time evidence of arthrosis becomes ubiquitous. This study shows that men have both a greater prevalence and degree of facet arthrosis than women at all levels of the lumbar spine. The L4-5 level shows the highest prevalence and degree of arthrosis.
Most aspects of facet arthrosis are based on the pathogenesis of degenerative cascade in the context of a 3-joint complex. This complex involves the articulations between 2 vertebrae consisting of the intervertebral disc and adjacent facet joints. Changes within each member of this joint complex will result in changes in the others in the lumbar and cervical spine. It also has been shown that the prevalence of disc degeneration, spondylosis, and facet joint osteoarthritis increases with increasing age. Others have shown simultaneous disc degeneration in the cervical and lumbar spine. Similarly, spondylosis is also common in the cervical and lumbar spine. Spondylosis is often used to describe vertebral osteophytosis secondary to degenerative disc disease or osteophytosis of the facet joints. However, spondylosis only accurately describes vertebral osteophytosis secondary to degenerative disc disease. Consequently, osteophytes occurring at the facet joints are different from osteophytes occurring on the vertebral margins adjacent to the disc.
Radiographic changes of osteoarthritis have been shown to be equally common in patients with and without low back or neck pain and degenerative joints een on computed tomography (CT) are not always painful, even though some studies report severely degenerated joints as being more likely to be symptomatic. As per the descriptions of degenerative cascade in the context of a 3-joint complex, it is viewed with involvement of changes in the disc structure and composition paralleling changes in the articular cartilage and ligaments of joints. Thus, it is reasonable to assume that in a patient suffering with either neck pain or low back pain, the causative structures of that pain may be the same in both regions, either discs or facet joints, and these degenerative changes increase with age. In fact, increasing age has been associated with an increase in musculoskeletal symptoms, specifically low back pain. The prevalence of back pain based on age has been estimated to be 15% in children, adolescents, and adults, and 27% in the elderly. It is also stated that there has been an under-representation of the older population in the back pain literature, suggesting that the prevalence of low back pain in this population is not known with certainty and is not compatible with that in the younger age population.
Early studies of low back pain by Schwarzer et al showed the prevalence of facet joint involvement to be approximately 15% in the younger population and 45% in the middle aged population. In contrast, facet joint-related chronic low back pain has been shown to have a prevalence of 52% in the elderly. To date, however, the age-related prevalence of facet joint involvement has not been studied for chronic neck pain.
