Department of Physical Medicine and Rehabilitation, Physical Therapy Program, University of Colorado School of Medicine, Aurora, CO, USA.
Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, USA.
Exp Brain Res. 2022 Jan;240(1):279-288. doi: 10.1007/s00221-021-06272-9. Epub 2021 Dec 2.
Spinal cord epidural stimulation (scES) is an intervention to restore motor function in those with severe spinal cord injury (SCI). Spinal cord lesion characteristics assessed via magnetic resonance imaging (MRI) may contribute to understand motor recovery. This study assessed relationships between standing ability with scES and spared spinal cord tissue characteristics at the lesion site. We hypothesized that the amount of lateral spared cord tissue would be related to independent extension in the ipsilateral lower limb. Eleven individuals with chronic, clinically motor complete SCI underwent spinal cord MRI, and were subsequently implanted with scES. Standing ability and lower limb activation patterns were assessed during an overground standing experiment with scES. This assessment occurred prior to any activity-based intervention with scES. Lesion hyperintensity was segmented from T2 axial images, and template-based analysis was used to estimate spared tissue in anterior, posterior, right, and left spinal cord regions. Regression analysis was used to assess relationships between imaging and standing outcomes. Total volume of spared tissue was related to left (p = 0.007), right (p = 0.005), and bilateral (p = 0.011) lower limb extension. Spared tissue in the left cord region was related to left lower limb extension (p = 0.019). A positive trend (p = 0.138) was also observed between right spared cord tissue and right lower limb extension. In this study, MRI measures of spared spinal cord tissue were significantly related to standing outcomes with scES. These preliminary results warrant future investigation of roles of supraspinal input and MRI-detected spared spinal cord tissue on lower limb motor responsiveness to scES.
脊髓硬膜外刺激 (scES) 是一种恢复严重脊髓损伤 (SCI) 患者运动功能的干预措施。通过磁共振成像 (MRI) 评估的脊髓损伤特征可能有助于了解运动恢复情况。本研究评估了站立能力与脊髓损伤部位保留的脊髓组织特征之间的关系。我们假设，外侧保留的脊髓组织量与同侧下肢的独立伸展有关。11 名慢性、临床完全性 SCI 患者接受了脊髓 MRI 检查，并随后植入了 scES。在 scES 过地站立实验中评估了站立能力和下肢激活模式。该评估发生在任何基于活动的 scES 干预之前。从 T2 轴位图像中分割出损伤高信号，使用基于模板的分析来估计脊髓前、后、右和左侧的保留组织。回归分析用于评估影像学和站立结果之间的关系。保留组织的总体积与左侧（p=0.007）、右侧（p=0.005）和双侧（p=0.011）下肢伸展有关。左侧脊髓区域的保留组织与左侧下肢伸展有关（p=0.019）。右侧保留脊髓组织与右侧下肢伸展之间也观察到正趋势（p=0.138）。在这项研究中，MRI 测量的保留脊髓组织与 scES 的站立结果显著相关。这些初步结果证明了未来需要进一步研究皮质下输入和 MRI 检测到的保留脊髓组织对 scES 下肢运动反应的作用。
