Department of Orthopaedic Surgery - Spine Unit, Inselspital, Bern University Hospital, 3010, Freiburgstrasse, Bern, Switzerland.
Spine Medicine Bern, Hirslanden Salem-Spital, Bern, Switzerland.
Eur Spine J. 2021 Sep;30(9):2570-2576. doi: 10.1007/s00586-021-06810-7. Epub 2021 Mar 19.
Factors influencing paraspinal muscle degeneration are still not well understood. Fatty infiltration is known to be one main feature of the degeneration cascade. The aim of this cross-sectional study was to illustrate the 3D cluster of paraspinal lumbar muscle degeneration on T2-weighted MRI images using our newly developed software application 'iSix'.
Mono- (Mm. rotatores), multi- (Mm. multifidus) and pluri-segmental (M. erector spinae) lumbar muscles groups were segmented on T2-weighted MR sequences using a novel computer-assisted technique for quantitative muscle/fat discrimination. The degree of fatty infiltration of the three predefined muscle groups was compared on a 3-dimensional basis, with regard to segment involvement and age. General linear models were utilized for statistical comparison.
N = 120 segments (age: 52.7; range 16-87 years) could be included. The overall relative fatty infiltration of the mono-segmental muscles was higher (21.1 14.5%) compared to the multi-segmental (16.0 8.8% p = 0.049) and pluri-segmental muscles (8.5 8.0%; p = 0.03). Mono-segmental muscles on the levels L4/5 (22.9 ± 10.2 [CI 17.6-28.2] %) and L5/S1 (27.01 ± 15.1 [CI 21.4-32.7] %) showed a significant higher amount of fat compared to the levels L2/3 (8.2 ± 6.8 [CI 2.2-14.2] %; L4/5 vs. L2/3, p = 0.03; L5/S1 vs. L2/3, p = 0.02) and L3/4 (13.2 ± 5.4 [CI 8.6-17.7]%; L4/5 vs. L3/4, p = 0.02; L5/S1 vs. L3/4, p < 0.01). Multivariate linear regression analyses revealed age and Pfirrmann grade as independent factors for fatty muscle degeneration.
3D analysis of fatty infiltration is an innovative tool to study lumbar muscle degeneration. Mono-segmental muscles are more severely affected by degeneration compared to multi-/pluri-segmental muscles, especially at the L4/5 and L5/S1 level. Age and disc degeneration independently correlate with muscle degeneration.
影响脊柱旁肌退变的因素仍不清楚。脂肪浸润是退变级联反应的主要特征之一。本横断面研究的目的是使用我们新开发的软件应用程序“iSix”，在 T2 加权 MRI 图像上说明腰椎脊柱旁肌肉退变的 3D 聚类。
使用新的计算机辅助定量肌肉/脂肪鉴别技术，在 T2 加权 MR 序列上对单（旋转肌）、多（多裂肌）和多节段（竖脊肌）腰椎肌肉群进行分割。在三维基础上，比较三个预设肌肉群的脂肪浸润程度，涉及节段受累和年龄。利用广义线性模型进行统计比较。
共纳入 120 个节段（年龄：52.7 岁；范围 16-87 岁）。单节段肌肉的总体相对脂肪浸润较高（21.1±14.5%），多节段肌肉（16.0±8.8%，p=0.049）和多节段肌肉（8.5±8.0%，p=0.03）。L4/5 水平（22.9±10.2 [CI 17.6-28.2]%）和 L5/S1 水平（27.01±15.1 [CI 21.4-32.7]%）的单节段肌肉的脂肪含量明显高于 L2/3 水平（8.2±6.8 [CI 2.2-14.2]%；L4/5 与 L2/3，p=0.03；L5/S1 与 L2/3，p=0.02）和 L3/4 水平（13.2±5.4 [CI 8.6-17.7]%；L4/5 与 L3/4，p=0.02；L5/S1 与 L3/4，p<0.01）。多变量线性回归分析显示，年龄和 Pfirrmann 分级是脂肪性肌肉退变的独立因素。
脂肪浸润的 3D 分析是研究腰椎肌肉退变的一种创新工具。与多/多节段肌肉相比，单节段肌肉退变更严重，尤其是在 L4/5 和 L5/S1 水平。年龄和椎间盘退变与肌肉退变独立相关。
