To determine consensus among an international, multidisciplinary group of experts regarding definitions of spinal osteoarthritis for research and for clinical practice.
A 15 member, multidisciplinary steering committee generated 117 statements for a three-round Delphi study. Experts in back pain and/or osteoarthritis were identified and invited to participate. In round one, participants could propose additional statements for voting. All statements were rated on a 1-9 Likert scale, and consensus was set at ≥70% of respondents agreeing or disagreeing with the statement and <15% of respondents providing the opposite response.
In total, 255 experts from 11 different professional backgrounds were invited. From 173 available experts, 116 consented to participate. In round one, 103 participants completed the survey, followed by 85 of 111 participants in round two (77%) and 87 of 101 participants in round three (86%). One third of participants were from Europe (30%), most were male (58%), one fifth were physiotherapists (21%), and over one third had been in their profession for 11-20 years (35%). Of 131 statements, consensus was achieved for 71 statements (54%): 53 in agreement (75%) and 18 in disagreement (25%).
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.