Characteristics of spinopelvic alignment in Parkinson's disease: Comparison with adult spinal deformity

The characteristics and pathogenesis of spinopelvic alignment in Parkinsons's disease (PD) patients-including differences compared to non-PD subjects and their relationships with the severity of PD-have not been clarified. The aim of this study was to investigate the characteristics of spinopelvic alignment in patients with PD.

Forty-eight PD patients complaining of chronic low back pain were included (PD group). The PD condition, determined using the Hoehn and Yahr (H&Y) stage and Unified Parkinson Disease Rating Scale (UPDRS) score; radiographic spinopelvic alignment; lumbar range of motion (ROM); and low back pain-related quality of life assessments were evaluated. Fifty age- and sex-matched patients with adult spinal deformities were included as controls (ASD group).

The spinopelvic alignments of the PD/ASD groups demonstrated sagittal vertical axes of 120.9/106.3 mm and pelvic incidences of 49.7/52.9°, with no significant differences. Conversely, there were significant differences in the thoracic kyphosis (TK; 27.6/16.7°), lumbar lordosis (-22.7/-7.9°), and pelvic tilt (25.3/34.4°) (all, p < 0.05). With regard to correlations with the PD condition, the H&Y stage demonstrated significant correlations with the sagittal vertical axis, thoracolumbar kyphosis, and lumbar ROM (all, p < 0.05), and the UPDRS score tended to correlate with the TK and thoracolumbar kyphosis (both, p < 0.01).

Characteristic spinal conditions in PD exist, with progressed PD condition causing stooped posture with increased thoracic or thoracolumbar kyphosis and decreased lumbar ROM; moreover, global sagittal malalignment progresses without sufficient compensatory mechanisms such as loss of TK and pelvic retroversion.