Be cautious about relying heavily on inflammatory back pain criteria that were developed for ankylosing spondylitis.
Reference1. Yap KS, Ye JY, Li S, Gladman DD, Chandran V. Back pain in psoriatic arthritis: defining prevalence, characteristics and performance of inflammatory back pain criteria in psoriatic arthritis. Ann Rheum Dis. 2018 Aug 4. pii: annrheumdis-2018-213334. doi: 10.1136/annrheumdis-2018-213334. [Epub ahead of print]