Morphological changes of cervical facet joints in elderly individuals

To better understand the role of facet joint degeneration in chronic neck and back pain epidemiological and morphological data are needed. For the cervical spine, however, such data are rare. Therefore, the aim of this study was to determine the degree of cartilage degeneration of cervical facet joints with respect to spinal level and age, to investigate whether any region of the joint surface is more often affected by degeneration and to determine the localisation of osteophytes. A total of 128 left-sided facet surfaces from 15 fresh frozen cervical spine specimens (59-92 years) including in maximum C2-C7 were inspected in a way to ensure a direct comparability to data reported for the lumbar spine. First, the macroscopic degree of cartilage degeneration was determined and correlated to spinal level and age. Then, each facet surface was divided into five regions (anterior, posterior, lateral, medial and central) to check whether cartilage degeneration occurs more often in any of these regions. Finally, the localisation of osteophytes was determined. The results showed that the mean degree of cartilage degeneration was 2.8 (+/- 0.6) on a scale from Grade 1 (no degeneration) to 4 (severe degeneration). None of all 128 facet surfaces was classified as Grade 1. All spinal levels had about the same degree of degeneration (in mean 2.5-3.0). The youngest age group (< 70 years) had a somewhat lower degree of degeneration (2.6) than the oldest (>= 90 years) (3.1). Cartilage defects were found all over the joint surfaces, none of the five regions was more often affected than the others. Least osteophytes were found on the medial border of the facet joints. In conclusion, the prevalence of cervical facet joint degeneration is probably very high in individuals aged 50 years and more, with a tendency to increase in severity with age. All levels of the middle and lower cervical spine were affected to almost the same degree, whereas in the lumbar spine an increase in degeneration towards the lower levels was reported. Also, in the cervical spine in most cases the cartilage was evenly degenerated all over the joint surface while in the lumbar spine certain regions were reported to be affected predominantly.