The natural course of radiographic progression in ankylosing spondylitis: differences between genders and appearance of characteristic radiographic features.

Our study set out to analyze the radiographic progression of ankylosing spondylitis (AS) patients based on gender differences. A total of 146 AS patients were retrospectively blindly analyzed in at least 2 time points within 6 years using the modified Stokes AS Spine Score. The mean follow-up time was 3.8 ± 1.7 years, and 114 patients (78%) were male. The overall progression was similar between genders. Females showed higher progression in the cervical spine, and males in the lumbar spine. More females showed new cervical syndesmophytes, and more males showed new lumbar syndesmophytes. More females showed slow radiographic progression, and more males showed fast radiographic progression, while moderate progression was similar for both genders. Dorsal syndesmophytes showed no impact in the prediction of future progression. Female AS patients showed more cervical structural lesions, but male patients overall showed more rapid progress, leading us to conclude that dorsal vertebral edges do not add in depiction of radiographic deterioration in AS patients.