Abstract
Background Zygapophysial joints (Z joints) can be a source of back pain and of neck pain, but the cause of pain is not known. Some authors attribute the pain to osteoarthritis but without citing evidence.Objectives The present review was undertaken to determine if there was sufficient evidence of association between spinal pain and osteoarthritis of Z joints to justify osteoarthritis being held to be the cause of pain. The null hypothesis was that osteoarthritis of Z joints does not cause back pain or neck pain.Eligibility criteria Relevant studies were ones that provided primary data on the association between pain and osteoarthritis of Z joints. These could be population studies, diagnostic studies, or case-control studies.Sources of evidence The database of PubMed was searched using the terms: Lumbar or cervical, zygapophysial or facet, pain, and osteoarthritis or degeneration or degenerative.Charting methods Data pertinent to the research question were extracted from original articles and tabulated for reporting. Odds ratios for associations were calculated, as were the prevalence rates of osteoarthritis in subjects with pain, and conversely the prevalence rates of pain in subjects with osteoarthritis.Results The searches retrieved 11 population studies, 4 diagnostic studies, and 3 cases control studies. No study showed any positive association between osteoarthritis of Z joints and pain. All studies found pain to be independent of the presence or severity of osteoarthritis. Osteoarthritis was as common in subjects with no pain as in subjects with pain. The null hypothesis was not refuted.Conclusion The published evidence does not support the belief that osteoarthritis causes Z joint pain. All the evidence contradicts this belief.