國際脊椎關節炎評估學會(Assessment of Spondylarthritis International Society,ASAS)提出的中軸脊椎關節炎(英语:axial spondyloarthritis)分類標準(簡稱 ASAS 標準)適用於「腰痛持續時間大於或等於3個月」且「發病年齡小於 45 歲」的患者[11]。還可再細分為兩大類[12][13]:
^Rudwaleit, M; Landewe, R; van der Heijde, D; Listing, J; Brandt, J; Braun, J; Burgos-Vargas, R; Collantes-Estevez, E; Davis, J; Dijkmans, B; Dougados, M; Emery, P; van der Horst-Bruinsma, I E; Inman, R; Khan, M A; Leirisalo-Repo, M; van der Linden, S; Maksymowych, W P; Mielants, H; Olivieri, I; Sturrock, R; de Vlam, K; Sieper, J. The development of Assessment of SpondyloArthritis international Society classification criteria for axial spondyloarthritis (part I): classification of paper patients by expert opinion including uncertainty appraisal. Annals of the Rheumatic Diseases. 17 March 2009, 68 (6): 770–776. PMID 19297345. doi:10.1136/ard.2009.108217.
^Rudwaleit, M; van der Heijde, D; Landewe, R; Listing, J; Akkoc, N; Brandt, J; Braun, J; Chou, C T; Collantes-Estevez, E; Dougados, M; Huang, F; Gu, J; Khan, M A; Kirazli, Y; Maksymowych, W P; Mielants, H; Sorensen, I J; Ozgocmen, S; Roussou, E; Valle-Onate, R; Weber, U; Wei, J; Sieper, J. The development of Assessment of SpondyloArthritis international Society classification criteria for axial spondyloarthritis (part II): validation and final selection. Annals of the Rheumatic Diseases. 17 March 2009, 68 (6): 777–783. PMID 19297344. doi:10.1136/ard.2009.108233.
^Hoving JL, Lacaille D, Urquhart DM, Hannu TJ, Sluiter JK, Frings-Dresen MH. Non-pharmacological interventions for preventing job loss in workers with inflammatory arthritis. The Cochrane Database of Systematic Reviews. 2014, 11 (11): CD010208. PMID 25375291. doi:10.1002/14651858.CD010208.pub2.