Department of Orthopaedic Surgery, Osaka City University Graduate School of Medicine, 1-4-3 Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan.
Department of Orthopaedic Surgery, Shiraniwa Hospital, Nara, Japan.
Sci Rep. 2021 Jan 26;11(1):2179. doi: 10.1038/s41598-021-82015-8.
Compensatory mechanisms, such as a decrease in thoracic spine kyphosis and posterior tilting or rotation of the pelvis, aim to achieve optimal alignment of the spine. However, the effect of muscle strength on these compensatory mechanisms has not been elucidated. This study aimed to investigate the impact of back muscle and lower extremity strength on compensatory mechanisms in elderly people. Overall, 409 community-dwelling elderly participants (164 men, 245 women) were included. Age, disc degeneration, and 2 or more vertebral fractures showed a significant increase of risk for sagittal vertical axis (SVA) deterioration. Conversely, stronger back, hip flexor, and knee extensor muscles reduced the risk for SVA deterioration. To investigate the association of each muscle's strength with compensatory mechanisms, 162 subjects with pelvic incidence-lumbar lordosis > 10° were selected. The linear regression model for thoracic kyphosis demonstrated a negative correlation with back muscle strength and positive correlation with vertebral fracture. The regression analysis for pelvic tilt demonstrated a positive correlation with knee extensor strength. Back, hip flexor, and knee extensor muscle strength were associated with sagittal spinal alignment. Back muscle strength was important for the decrease in thoracic kyphosis, and knee extensor strength was associated with pelvic tilt.
代偿机制，如胸椎后凸减少、骨盆后倾或旋转，旨在实现脊柱的最佳对齐。然而，肌肉力量对这些代偿机制的影响尚未阐明。本研究旨在探讨腰背肌和下肢力量对老年人代偿机制的影响。共有 409 名社区居住的老年人（164 名男性，245 名女性）参与了研究。年龄、椎间盘退变和 2 个或更多椎体骨折显著增加了矢状垂直轴（SVA）恶化的风险。相反，更强壮的腰背肌、髋关节屈肌和膝关节伸肌降低了 SVA 恶化的风险。为了研究每块肌肉力量与代偿机制的关系，选择了骨盆入射角-腰椎前凸角>10°的 162 名受试者。胸椎后凸的线性回归模型显示与腰背肌力量呈负相关，与椎体骨折呈正相关。骨盆倾斜的回归分析显示与膝关节伸肌力量呈正相关。腰背肌、髋关节屈肌和膝关节伸肌力量与矢状位脊柱排列有关。腰背肌力量对降低胸椎后凸很重要，而膝关节伸肌力量与骨盆倾斜有关。
