Bone-Targeted Therapies and Spinal Morphometry in Postmenopausal Osteoporosis: A Real-World Longitudinal Retrospective Study

This 24-month retrospective, exploratory observational study evaluated longitudinal spinal morphometric changes in 128 postmenopausal women with osteoporosis receiving anabolic therapy (n = 30) or non-anabolic anti-osteoporotic therapy (n = 98). Lumbar BMD, lower lumbar vertebral heights, disc height indices, and sagittal spinopelvic parameters were assessed at baseline and 24 months. Unweighted and baseline-severity adjusted linear regression models were used; IPTW and overlap-weighted analyses were performed as sensitivity analyses. Both groups showed significant lumbar BMD improvement. Patients receiving anabolic therapy were older and had lower baseline lumbar BMD and greater thoracolumbar kyphosis, indicating confounding by indication. In unweighted models, anabolic therapy was associated with greater L5 anterior height loss and L5/S1 disc height index preservation; however, these associations were attenuated after adjustment for baseline lumbar BMD and thoracolumbar kyphosis and were not consistently supported by propensity-score-weighted sensitivity analyses. Pelvic incidence showed more consistent level-specific associations, being negatively associated with L5 anterior height change and positively associated with L5/S1 disc height index preservation. Given substantial confounding by indication and limited treatment-group overlap, treatment-related associations should not be interpreted causally. These findings suggest that spinopelvic morphology may influence lower lumbar structural adaptation, whereas treatment-related morphometric findings remain exploratory and require confirmation.