Correlation Between Paravertebral Muscles Degeneration and Spinopelvic Parameters in Patients With Osteoporotic Vertebral Compression Fractures.

BACKGROUND Osteoporotic vertebral compression fractures (OVCFs) are correlated with thoracolumbar sagittal imbalance associated with paravertebral muscles (PVM) atrophy and fatty infiltration (FI). This study investigated PVM degeneration and its correlation with spinopelvic parameters in patients with OVCFs. MATERIAL AND METHODS This retrospective case-control study enrolled 50 patients with OVCFs and 50 controls with lumbar degeneration, frequency-matched for age (±5 years). Complete sex matching was not achieved. Primary comparisons were adjusted for age, sex, BMI, and lumbar bone mineral density (BMD); subgroup analyses were exploratory and unadjusted. MRI measured the PVM from T11 to L2 and the cross-sectional area (CSA) and FI of the multifidus (MF) and erector spinae (ES) at L3. RESULTS Patients with OVCFs showed reduced CSA and increased FI (P<0.05). After adjustment, sagittal vertical axis, thoracic kyphosis, and pelvic tilt increased and lumbar lordosis (LL) decreased (all P≤0.003), whereas sacral slope (P=0.538) and pelvic incidence (P=0.602) did not differ. MF and ES CSA correlated negatively with SVA and positively with LL, while FI showed the opposite (all P<0.01). In exploratory analyses, patients aged ≥65 years had a larger SVA (P=0.040), and women a smaller LL and lower BMD (both P<0.05); no PVM differences were seen across subgroups. CONCLUSIONS In this cross-sectional cohort, PVM degeneration correlated with sagittal malalignment after adjustment for measured confounders (adjusted cross-sectional associations). Advanced age correlated with greater SVA, and female sex with smaller LL and lower BMD. No PVM differences were detected across subgroups. Further trials are required to validate targeted paravertebral rehabilitation strategies.