IL17A and ankylosing spondylitis: Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and Bath Ankylosing Spondylitis Functional Index (BASFI) were used to evaluate the spinal function and activity of the two groups, and the levels of CXC-type chemokine ligand 16 (CXCL16), Dickkopf-1(DKK-1), interleukin-17 (IL-17), tumor necrosis factor-α (TNF-α), sclerostin (SOST) ,and bone morphogenetic protein 2(BMP-2) in serum of the two groups were measured.