Can we resolve the conflation of activity-related enthesal bone changes with injury-derived enthesal reaction?

Abstract

Postreactive morphological alterations of enthesal surfaces, often termed historically and collectively as "enthesitis," were thought to reflect typical daily activities. Actually, an important real cause of altered enthesal surfaces is augmentation of the osseous base, a physiological reaction. Further, altered enthesal attachments often reveal partial-to-complete avulsion and dystrophic calcification (ossification) secondary to injury, a pathological process. Descriptively, the suffixes "sis," "osis," and "asis" (as appropriate grammatically) signal a general "affected with" state. The more preferred suffix "opathy" suggests pathology and does not indicate cause. In clinical terms, the suffix "itis" refers specifically to underlying inflammation, whereas suspected noninflammatory disease should be termed "osis" or "asis." From an archeological perspective, the underlying disease usually is not evident, and therefore, enthesopathy would be the more appropriate descriptor. Additionally, when describing apparent physiological responses to normal stressors, "osseous surface augmentation" is appropriate. Importantly, then, the suffix "itis" is associated with defined tissue cellularity, systemic hematology, and clinical signs of heat, swelling, redness, and pain. Where the latter observations are not possible, the "itis" inference is indirect at best. In most of the latter instances, the "itis" suffix should be limited to a properly constructed differential diagnosis list.