Flare-ups of osteoarthritis: what do they mean in the short-term and the long-term?

Symptoms of osteoarthritis (OA) evolve over years with variable rate and course. While studies have focused on understanding long-term trajectories of OA [e.g.,1], how these relate to shorter-term fluctuations in symptoms is not well-understood. Yet for many people, the lived experience of OA is recurrent fluctuations in episodic pain of varying frequency, intensity and duration; it is these episodes of increased pain and associated disability that often drive primary healthcare consultation. Historically, the term ‘exacerbation’ and ‘flare-up’ have been used interchangeably to describe sudden-onset episodes of increased pain; the term ‘flare-up’ has been adopted herein2.