Summary

Osteosarcopenia is a common condition among elderly and postmenopausal female patients. Site-specific bone mineral density is more predictive of bone-related complications. Few studies have investigated muscle-bone associations. Our results demonstrated that in women, significant positive associations between paraspinal muscles FCSA and vBMD exist at different lumbosacral levels. These regional differences should be considered when interpreting bone-muscle associations in the lumbar spine.

Introduction

There is increasing evidence between bone and muscle volume associations. Previous studies have demonstrated comorbidity between osteoporosis and sarcopenia. Recent studies showed that sarcopenic subjects had a fourfold higher risk of concomitant osteoporosis compared to non-sarcopenic individuals. Although site-specific bone mineral density (BMD) assessments were reported to be more predictive of bone-related complications after spinal fusions than BMD assessments in general, there are few studies that have investigated level-specific bone-muscle interactions. The aim of this study is to investigate the associations between muscle functional cross-sectional area (FCSA) on magnetic resonance imaging (MRI) and site-specific quantitative computed tomography (QCT) volumetric bone mineral density (vBMD) in the lumbosacral region among spine surgery patients.

Methods

We retrospectively reviewed a prospective institutional database of posterior lumbar fusion patients. Patients with available MRI undergoing posterior lumbar fusion were included. Muscle measurements and FCSA were conducted and calculated utilizing a manual segmentation and custom-written program at the superior endplate of the L3–L5 vertebrae level. vBMD measurements were performed and calculated utilizing a QCT pro software at L1–L2 levels and bilateral sacral ala. We stratified by sex for all analyses.

Results

A total of 105 patients (mean age 61.5 years and 52.4% females) were included. We found that female patients had statistically significant lower muscle FCSA than male patients. After adjusting for age and body mass index (BMI), there were statistically significant positive associations between L1–L2 and S1 vBMD with L3 psoas FCSA as well as sacral ala vBMD with L3 posterior paraspinal and L5 psoas FCSA. These associations were not found in males.

Conclusions

Our results demonstrated that in women, significant positive associations between the psoas and posterior paraspinal muscle FCSA and vBMD exist in different lumbosacral levels, which are independent of age and BMI. These regional differences should be considered when interpreting bone and muscle associations in the lumbar spine.

中文翻译：

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MRI 上腰椎椎旁肌功能横截面积与定量计算机断层扫描测量的区域体积骨矿物质密度之间的关联

概括

骨质疏松症是老年和绝经后女性患者的常见病症。特定部位的骨矿物质密度更能预测骨相关并发症。很少有研究调查肌肉-骨骼关联。我们的结果表明，在女性中，不同腰骶水平的椎旁肌 FCSA 和 vBMD 之间存在显着正相关。在解释腰椎的骨骼肌肉关联时，应考虑这些区域差异。

介绍

越来越多的证据表明骨骼和肌肉体积之间存在关联。以前的研究表明骨质疏松症和肌肉减少症之间存在共病。最近的研究表明，与非肌肉减少症个体相比，肌肉减少症患者伴发骨质疏松症的风险高四倍。尽管据报道特定部位的骨密度 (BMD) 评估比一般的 BMD 评估更能预测脊柱融合术后骨相关并发症，但很少有研究调查特定水平的骨-肌肉相互作用。

方法

我们回顾性回顾了后路腰椎融合术患者的前瞻性机构数据库。包括进行后路腰椎融合术的可用 MRI 患者。肌肉测量和 FCSA 是在 L3-L5 椎骨水平的上端板使用手动分割和自定义编写的程序进行和计算的。使用 QCT pro 软件在 L1-L2 水平和双侧骶骨翼进行 vBMD 测量和计算。我们按性别对所有分析进行分层。

结果

总共包括 105 名患者（平均年龄 61.5 岁，52.4% 为女性）。我们发现女性患者的肌肉 FCSA 明显低于男性患者。调整年龄和体重指数 (BMI) 后，L1-L2 和 S1 vBMD 与 L3 腰大肌 FCSA 以及骶骨翼 vBMD 与 L3 后椎旁肌和 L5 腰大肌 FCSA 之间存在统计学显着正相关。这些关联未在男性中发现。

结论

我们的研究结果表明，在女性中，腰大肌和脊旁后肌 FCSA 和 vBMD 之间的显着正相关存在于不同的腰骶水平，这与年龄和 BMI 无关。在解释腰椎的骨骼和肌肉关联时，应考虑这些区域差异。