Correlation between intervertebral disc degeneration and bone mineral density difference: a retrospective study of postmenopausal women using an eight-level MRI-based disc degeneration grading system

PURPOSE: To explore the correlation between intervertebral disc degeneration (IDD) and bone mineral density (BMD) difference between adjacent vertebrae. METHODS: A retrospective analysis of 114 postmenopausal women who were treated in our hospital from January 2021 to December 2021. The degree of lumbar(L)1–5 IDD was scored according to an 8-grade scoring system. The lumbar vertebrae BMD was detected, and the BMD difference was calculated. The subjects were grouped according to age and whether the disc was severe IDD. Data were collected for statistical analysis. RESULTS: The prevalence of osteoporosis in the 51–60-year-old group was lower than that in the other groups, while the prevalence of modic changes in the 71–80-year-old group was higher than that in the 51–70-year-old group (P < 0.05). At the L1/2 level, the prevalence of severe IDD in the 81-90y group was higher than that in the 51-70y group (P < 0.05). At the L2/3 level, the prevalence of severe IDD in the 71-90y group was higher than that in the 51-60y group, and the prevalence of severe IDD in the 71-80y group was higher than that in the 61-70y group (P < 0.05). The L2/3 disc score was positively correlated with the L3-L2 BMD difference (P < 0.05). At the level of L1-2, the BMD difference in the non-severe IDD group was smaller than that in the severe IDD group (P < 0.05). CONCLUSION: For postmenopausal women, an increase in BMD difference is correlated with IDD. Osteoporosis is more common in people over 60 years old, and the possibility of modic change in 71-80y is higher than in other age groups. The incidence of severe IDD also increases with aging, especially for the L1/2 and L2/3 discs.