Consensus for statements regarding a definition for spinal osteoarthritis for use in research and clinical practice: A Delphi study.

While there was consensus for statements for definitions of spinal osteoarthritis that were analogous to definitions of osteoarthritis in appendicular joints, a future definition still needs refinement. Importantly, this Delphi highlighted that a future definition should be considered across a spectrum of structural changes and patient symptoms, and expressed on a progressive scale.