Posture, balance and gait in axial spondyloarthritis: a case-control study

Axial spondyloarthritis (axSpA) is a chronic inflammatory disease that primarily involves the axial skeleton but may also present with peripheral joint involvement and extra-articular involvement. The present study aims to quantitatively analyze posture, balance, and gait parameters in patients with axSpA and and assess associated factors. This cross-sectional case-control study included 51 axSpA patients (30 males, 21 females; mean age 40.94 ± 10.48 years) and 51 age- and sex-matched healthy controls. In patients with axSpA, the Ankylosing Spondylitis Disease Activity Score CRP, the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), the Bath Ankylosing Spondylitis Functional Index (BASFI), the Bath Ankylosing Spondylitis Metrology Index (BASMI), the Maastrich Ankylosing Spondylitis Enthesitis Score (MASES), and the Ankylosing Spondylitis Quality of Life (ASQoL) scale were used. For postural analysis, DIERS formetric (Diers GmbH, Schlangenbad, Germany) videoraster- stereography device was utilized. HUR SmartBalance BTG4 (HUR-labs Oy, Kokkola, Finland) balance platform was used for postural balance and limit of stability (LOS) measurement. Participants were evaluated using Berg Balance Scale (BBS), Functional Reach Test (FRT) and Timed Up and Go Test (TUG). The Zebris FDM type 3 (Zebris Medical GmbH, Germany) walking platform was used to measure the spatiotemporal parameters of the participants. Comparison of postural parameters showed that sagittal imbalance and cervical depth distance were increased in the axSpA group than in the healthy participants (p < 0.004). Comparison of functional balance parameters showed that BBS and FRT scores were significantly lower (p < 0.001) in the axSpA group than in the control group, while TUG scores were significantly higher (p < 0.001). The LOS values, which evaluate dynamic balance were significantly lower, indicating impairment, in the axSpA group. In the measurement of postural sway, which indicates static balance, all 23 subparameters were found to be similar. When analyzing the spatiotemporal gait parameters, in the axSpA group compared with those in the control group; Foot angles (p= 0.028) and stride width (p = 0.004) were increased, whereas step lengths (p = 0.004) and stride lengths (P = 0.004) were decreased. In the axSpA group the gait speed was decreased (p = 0.004). When axSpA was analyzed separately as radiographic and nonradiographic axSpA, similar findings were observed in posture, balance, and gait parameters. No significant difference was observed. We found that the clinical assessments most closely associated with posture, balance, and gait analyses were BBS, FRT, TUG, and BASFI.