Department of Rehabilitation Medicine, SMG-SNU Boramae Medical Center, Seoul National University College of Medicine, Seoul, South Korea.
Department of Radiology, SMG-SNU Boramae Medical Center, Seoul National University College of Medicine, Seoul, South Korea.
J Cachexia Sarcopenia Muscle. 2021 Aug;12(4):913-920. doi: 10.1002/jcsm.12721. Epub 2021 May 28.
Here, we aimed to propose novel lateral whole-body dual-energy X-ray absorptiometry (lateral DXA) as a simple tool for measuring spinal muscle mass and investigate the feasibility of lateral DXA to measure lumbar paraspinal muscle (LPM) mass compared with lumbosacral spine three-dimensional magnetic resonance imaging (3D MRI).
Twenty consecutive participants were enrolled from a prospective observational cohort (SarcoSpine study). Lateral DXA was scanned with each participant in the lateral decubitus position. The region of interest was defined to analyse the LPM mass. LPM total volume, LPM cross-sectional area at the L3 mid-vertebra and L4/5 mid-disc levels and each signal intensity were measured by 3D MRI. Isokinetic and isometric back extensor muscle strengths as well as back extensor endurance were examined. The correlation between lateral DXA-based mass (weight) and 3D MRI-based LPM volume was analysed.
The mean age of the 20 participants (15 women, 5 men) was 72.2 ± 4.9 years. LPM mass by lateral DXA was positively correlated with LPM volume by 3D MRI (β = 0.333, r = 0.692, p < 0.001) and negatively correlated with signal intensity of the total LPM (β = -0.263, r = -0.530, p = 0.016). LPM mass was also correlated with appendicular limb muscle mass, handgrip strength and gait speed as well as back extensor endurance (r = 0.620, p = 0.004).
Our data suggest that LPM mass assessed by lateral DXA was positively correlated with LPM volume by 3D MRI in older adults. Lateral DXA may be a potential substitute for the cross-sectional area measurement of LPM mass. Further studies are required to validate this lateral DXA technique.
本研究旨在提出一种新的侧向全身双能 X 射线吸收法（侧向 DXA），作为测量脊柱肌肉质量的简便工具，并探讨侧向 DXA 测量腰椎旁肌（LPM）质量的可行性，与腰椎矢状面三维磁共振成像（3D MRI）进行比较。
从一项前瞻性观察队列研究（SarcoSpine 研究）中连续纳入 20 名参与者。在侧卧位下对每位参与者进行侧向 DXA 扫描。定义感兴趣区域以分析 LPM 质量。通过 3D MRI 测量 LPM 总容积、L3 中脊椎和 L4/5 中椎间盘水平的 LPM 横截面积以及每个信号强度。还检查了等速和等长背伸肌力量以及背伸肌耐力。分析了基于侧向 DXA 的质量（重量）与基于 3D MRI 的 LPM 容积之间的相关性。
20 名参与者（15 名女性，5 名男性）的平均年龄为 72.2 ± 4.9 岁。侧向 DXA 测定的 LPM 质量与 3D MRI 测定的 LPM 体积呈正相关（β=0.333，r=0.692，p<0.001），与总 LPM 信号强度呈负相关（β=-0.263，r=-0.530，p=0.016）。LPM 质量还与四肢肌肉质量、握力和步速以及背伸肌耐力相关（r=0.620，p=0.004）。
我们的数据表明，老年患者中侧向 DXA 测定的 LPM 质量与 3D MRI 测定的 LPM 体积呈正相关。侧向 DXA 可能是 LPM 质量的横截面积测量的潜在替代方法。需要进一步的研究来验证这种侧向 DXA 技术。
