Department of Orthopedic Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, Japan.
Department of Diagnostic Radiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, Japan.
Sci Rep. 2022 Aug 30;12(1):14717. doi: 10.1038/s41598-022-19000-2.
Age-related changes in the posterior extensor muscles of the cervical and lumbar spine have been reported in some studies; however, longitudinal changes in the thoracic spine of healthy subjects are rarely reported. Therefore, this study aimed to evaluate changes in the cross-sectional areas (CSAs) of posterior extensor muscles in the thoracic spine over 10 years and identify related factors. The subjects of this study were 85 volunteers (mean age: 44.7 ± 11.5) and the average follow-up period was about 10 years. The CSAs of the transversospinalis muscles, erector spinae muscles, and total CSAs of the extensor muscles from T1/2 to T11/12 were measured on magnetic resonance imaging. The extent of muscle fat infiltration was assessed by the signal intensity (luminance) of the extensor muscles' total cross-section compared to a section of pure muscle. We applied a Poisson regression model, which is included in the generalized linear model, and first examined the univariate (crude) association between each relevant factor (age, sex, body mass index, lifestyle, back pain, neck pain, neck stiffness, and intervertebral disc degeneration) and CSA changes. Then, we constructed a multivariate model, which included age, sex, and related factors in the univariate analysis. The mean CSAs of the transversospinalis muscles, erector spinae muscles, and total CSAs of the extensor muscles significantly increased over 10 years. Exercise habit was associated with increased CSAs of the erector spinae muscles and the total area of the extensor muscles. The cross-section mean luminance significantly increased from baseline, indicating a significant increase of fat infiltration in the posterior extensor muscles. Progression of disc degeneration was inversely associated with increased fat infiltration in the total extensor muscles.
一些研究报道了颈椎和腰椎的后伸肌群随年龄增长而发生的变化；然而，健康受试者胸段脊柱的纵向变化很少有报道。因此，本研究旨在评估 10 年内胸段脊柱后伸肌群横截面积（CSA）的变化，并确定相关因素。本研究的受试者为 85 名志愿者（平均年龄：44.7±11.5），平均随访时间约为 10 年。通过磁共振成像测量 T1/2 至 T11/12 节段的多裂肌、竖脊肌和后伸肌群的总 CSA。通过比较伸肌总横截面积的信号强度（亮度）与纯肌肉的信号强度来评估肌肉脂肪浸润的程度。我们应用了泊松回归模型，该模型包含在广义线性模型中，首先检查了每个相关因素（年龄、性别、体重指数、生活方式、背痛、颈痛、颈部僵硬和椎间盘退变）与 CSA 变化的单变量（粗）关联。然后，我们构建了一个多变量模型，其中包括单变量分析中的年龄、性别和相关因素。多裂肌、竖脊肌和后伸肌群的总 CSA 均值在 10 年内显著增加。运动习惯与竖脊肌和后伸肌群总 CSA 的增加有关。横断面平均亮度显著增加，表明后伸肌群的脂肪浸润明显增加。椎间盘退变的进展与总伸肌脂肪浸润的增加呈负相关。
