Wilson Saul, Abode-Iyamah Kingsley O, Miller John W, Reddy Chandan G, Safayi Sina, Fredericks Douglas C, Jeffery Nicholas D, DeVries-Watson Nicole A, Shivapour Sara K, Viljoen Stephanus, Dalm Brian D, Gibson-Corley Katherine N, Johnson Michael D, Gillies George T, Howard Matthew A
a Department of Neurosurgery , University of Iowa Hospitals and Clinics , Iowa City , IA , USA.
b Department of Veterinary Clinical Sciences , Iowa State University , Ames , IA , USA.
J Spinal Cord Med. 2017 May;40(3):346-360. doi: 10.1080/10790268.2016.1222475. Epub 2016 Oct 19.
To develop a large animal model of spinal cord injury (SCI), for use in translational studies of spinal cord stimulation (SCS) in the treatment of spasticity. We seek to establish thresholds for the SCS parameters associated with reduction of post-SCI spasticity in the pelvic limbs, with implications for patients.
The weight-drop method was used to create a moderate SCI in adult sheep, leading to mild spasticity in the pelvic limbs. Electrodes for electromyography (EMG) and an epidural spinal cord stimulator were then implanted. Behavioral and electrophysiological data were taken during treadmill ambulation in six animals, and in one animal with and without SCS at 0.1, 0.3, 0.5, and 0.9 V.
All surgical procedures were carried out at the University of Iowa. The gait measurements were made at Iowa State University.
Nine adult female sheep were used in these institutionally approved protocols. Six of them were trained in treadmill ambulation prior to SCI surgeries, and underwent gait analysis pre- and post-SCI. Stretch reflex and H-reflex measurements were also made in conscious animals.
Gait analysis revealed repeatable quantitative differences in 20% of the key kinematic parameters of the sheep, pre- and post-SCI. Hock joint angular velocity increased toward the normal pre-injury baseline in the animal with SCS at 0.9 V.
The ovine model is workable as a large animal surrogate suitable for translational studies of novel SCS therapies aimed at relieving spasticity in patients with SCI.
建立一种脊髓损伤（SCI）的大型动物模型，用于脊髓刺激（SCS）治疗痉挛的转化研究。我们试图确定与减轻SCI后后肢痉挛相关的SCS参数阈值，这对患者具有重要意义。
采用重物坠落法在成年绵羊中造成中度SCI，导致后肢轻度痉挛。然后植入用于肌电图（EMG）的电极和硬膜外脊髓刺激器。对6只动物在跑步机行走过程中以及1只动物在0.1、0.3、0.5和0.9V有或无SCS的情况下采集行为和电生理数据。
所有手术操作均在爱荷华大学进行。步态测量在爱荷华州立大学进行。
在这些经机构批准的方案中使用了9只成年雌性绵羊。其中6只在SCI手术前接受跑步机行走训练，并在SCI前后进行步态分析。还对清醒动物进行牵张反射和H反射测量。
步态分析显示，SCI前后绵羊20%的关键运动学参数存在可重复的定量差异。在0.9V的SCS作用下，受试动物跗关节角速度向损伤前正常基线增加。
绵羊模型作为一种大型动物替代模型是可行的，适用于旨在缓解SCI患者痉挛的新型SCS疗法的转化研究。
