The Effect of Surgical Alignment in Adult Scoliotic Spines on Axial Cyclic Vibration: A Finite Element Study

Finite element analysis was used to investigate the responses of five adult degenerative scoliosis (ADS) subjects to cyclic vibration before and after surgical alignment (SA). The dynamic responses of the healthy and presurgical scoliotic spines to the sinusoidal cyclic vibrations have been investigated in previous studies by computational and experimental approaches. However, no computational or experimental results were available for the pre- and postsurgical scoliosis subjects. The effect of the SA on the vibrational response of the postsurgical scoliosis subjects remained unknown. The objective of this study was to compare differences of the dynamic responses to the cyclic vibration input among the scoliotic spines for pre-and post-SA. Previous studies suggested that untreated scoliotic spines especially at the apical vertebrae are more sensitive to the vibration than spinal segments with normal anatomies. Results of this study showed that the SA was able to reduce the vibrational response of the scoliotic spines to the whole body vibrations (WBV) at the fused level while not significantly increase the response at the superior adjacent level, which suggested that SA is able to reduce the risk of further degeneration in the scoliotic spines.