Changes in bone tissue parameters and pain index in the lumbar spine in patients with rheumatoid arthritis

Introduction . Changes in the qualitative and quantitative parameters of bone tissue, the structure and density of the vertebrae, and intervertebral discs affect the severity of pain in the lumbar spine (LS). Pain in the LS in RA is less common than in the population and is associated with low functional activity and higher pain rates in general. Aim. To study changes in bone tissue parameters and pain index in the pelvic floor in patients with RA during long-term prospective observation. Materials and methods . The prospective multi-year cohort study included 151 women with RA aged 53.9 ± 9.2 years, with a follow-up period of 9.7 ± 1.7 years, with recurrence of pain in the pelvic area from 53.6 ± 12.2 years, which was assessed using the VAS scale (mm). All patients underwent clinical, laboratory and radiological examination of the pelvic area at baseline and over time. Results. Δ BMD in L1-L4 was -0.75%, in the SB – -8.6%, in the total hip – -5.3%. X-ray morphometry revealed the appearance or increase of the initial deformation (fractures) of the vertebrae in the POP without an increase in BMD in L1–L4 in 4 (2.6%) people. Degenerative changes increased in all analyzed segments of the POP. The number of patients with pain in the POP increased from 77 (51%) to 101 (67%) people, the pain intensity was 47 ± 21 points, became 51 ± 19 points. Conclusions. Long-term observation revealed stabilization of BMD in L1–L4; in patients younger than 55 years, a decrease was noted, and in patients older than 55 years, an increase in BMD. A relationship was established between the increase in BMD in L1–L4 and degenerative changes in the PP. Severe pain in the PP correlated with age, daily dose of glucocorticoids, RA activity according to DAS-28, health status assessment, and degenerative changes in the dynamics of the L2–L3, L3–L4, L4–L5 segments.