Cervical Facet-Mediated Pain

The cervical zygapophyseal joints, or facet joints, have long been implicated as a source of neck pain. This article examines the epidemiology of pain arising from these joints, as well as relevant anatomy and histology. An emphasis on clinical findings, examination, and imaging are presented, as well as a focus on whiplash-associated pain, in which the facet joints are frequently implicated as the source of pain. A semantic and lexical issue must be briefly discussed before commencement, however. The terms zygapophyseal joint and facet joint are often used interchangeably in the medical literature to name these joints, although the terms are not technically synonymous. The term zygapophysis, first used in 1854, and etymologically formed from the Greek for yoke and offshoot, refers specifically to the lateral process on the neural arch of a vertebra that articulates with the corresponding process of the next vertebra. The term facet is less specific, and is defined in the Oxford English Dictionary as a small, clearly delimited smooth area, especially an articular surface, on a vertebra or other bone. While zygapophyseal is more anatomically specific and may therefore be felt to be preferable in reference to this structure, the term facet appears to have greater acceptance based on usage in published studies. A recent PubMed search revealed a total of 3109 articles referring to this joint, of which 2737 (88%) referred to the facet joint exclusively, and 846 (27%) referred to the zygapophyseal joint exclusively. Fifteen percent of studies hedged and use both naming conventions. Sober evaluation of these findings reveals the uncomfortable truth that searching the literature for studies concerning this structure using only one or the other naming convention will miss a significant portion of the available evidence. In this article, the terms are used interchangeably, reflecting an appreciation for both the anatomic specificity of this structure, and the unequivocal preference for a more colloquial term among those who have studied and written about it.