Comparison of radiological changes in symphysis pubis and disease activity parameters in male patients with ankylosing spondylitis

Introduction: To determine the prevalence of involvement of symphysis pubis among male patients with ankylosing spondylitis (AS) and to analyze the relationship among this involvement, demographic data, clinical activity of the disease and radiological findings. Methods: Overall, 73 male patients diagnosed with AS who visited our clinic for follow-up were included in the study. In this retrospective study, clinical and radiological parameters were collected. In clinical evaluation, vertebral Visual Analog Scale (VAS) score, Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Metrology Index (BASMI) and Bath Ankylosing Spondylitis Functional Index (BASFI) were used. In AP pelvis radiography, symphysis pubis changes were rated as 0–4. Modified Stoke Ankylosing Spondylitis Spinal Score (M-SASSS) was calculated from the cervical and lumbar lateral radiography images. Results: Symphysis pubis involvement was radiologically observed in 45 patients (61.7%). The mean age (43.9 ± 12.6) of patients with symphysis pubis involvement was higher than the average (36.9 ± 9.0) of patients without involvement (p = 0.026). Average M-SASSS of patients with symphysis pubis involvement (15.9 ± 11.9) was higher than the average of patients without involvement (8.4 ± 7.4), and there was a significant positive correlation between symphysis pubis involvement and M-SASSS (p=0.002). BASDAI and BASMI averages of patients were not significant (p = 0.973 and p = 0.105, respectively). Conclusion: Symphysis pubis involvement is a common manifestation of AS and can be used to predict vertebral radiological involvement. Keywords: Ankylosing Spondylitis, Symphysis Pubis, Modified Stoke Ankylosing Spondylitis Spinal Score