Background: Spondyloarthritis represents a group of several inflammatory conditions. Ankylosing spondylitis and nr-axSpA are considered to belong to spondyloarthritis family of diseases.

Aim of the work: to evaluate bone mineral density (BMD) and trabecular bone scores(TBS) scores in patients suffering from non-radiographic axial spondyloarthritis (nr-axSpA).

Materials and Methods: A cross-sectional study evaluating 160 patients. Inclusion criteria involved patients 18-45 years of age, having clinical features of spondyloarthritis, and fulfilling Calin’s criteria for inflammatory low back pain. Patients were divided into 3 groups; group A (nr-axSpA) patients, group B (radiographic axial spondyloarthritis (r-axSpA)) patients, and group C (mechanical low back pain).

Results: Female to male ratio was significantly higher in group A compared to group B (63.3% vs. 36.7%) and (23.33% vs. 76.7%) (p< 0.001), respectively. While disease duration was significantly higher in group B in comparison to groups A and C (47.65±7.15, 18.56±6.55, and 14.76±4.20) (p<0.001), respectively. L1-L4 and L2-L4 TBS of groups A and B were significantly lower compared to group C (p<0.001). Additionally, a statistically significant decrease in BMD scores of L1-L4, femoral neck, and total hip bones was detected in group A compared to group C (p< 0.001).

Conclusion: Patients with nr-axSpA had a lower BMD and TBS compared to r-axSpA group (B) and control group (C), and it predominantly affected more females than males (3:1).

Keywords: Spondyloarthritis, nr-axSpA, r-axSpA, BMD, TBS, Egypt.

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Prof. Hesham Hamoud

Rheumatology Department, Al-Azhar University, Nasr City, Cairo, Egypt