Using Forelimb EMG to Control an Electronic Spinal Bridge to Facilitate Hindlimb Stepping After Complete Spinal Cord Lesion

2011 ◽  
Author(s):  
Parag Gad ◽  
Jonathan Woodbridge ◽  
Igor Lavrov ◽  
Yury Gerasimenko ◽  
Hui Zhong ◽  
...  

A complete spinal cord transection results in loss of all supraspinal motor control below the level of the injury. The neural circuitry in the lumbosacral spinal cord, however, can generate locomotor patterns in the hindlimbs of rats and cats with the aid of epidural stimulation and administration of serotoninergic agonists. We hypothesized that there are patterns of EMG signals from the forelimbs during quadrupedal locomotion that uniquely represent a signal for the “intent” to step with the hindlimbs. These observations led us to determine whether “indirect” volitional control of stepping can be restored after a complete spinal cord injury. We developed an electronic bridge that can trigger specific patterns of EMG activity from the forelimbs to enable quadrupedal stepping after a complete spinal cord transection in rats. We found dominant frequencies of 180–220 Hz in the EMG of forelimb muscles during active periods, whereas the frequencies were between 0–10 Hz when the muscles were inactive. A moving window detection algorithm was implemented in a small microprocessor to detect bilateral activity in the biceps brachii that then was used to initiate and terminate epidural stimulation. This detection algorithm was successful in detecting stepping under different pharmacological conditions and at various treadmill speeds and in facilitating quadrupedal stepping after a complete mid-thoracic spinal cord transection.

Author(s):  
Fedorova Jana ◽  
Kellerova Erika ◽  
Bimbova Katarina ◽  
Pavel Jaroslav

AbstractSpontaneous recovery of lost motor functions is relative fast in rodent models after inducing a very mild/moderate spinal cord injury (SCI), and this may complicate a reliable evaluation of the effectiveness of potential therapy. Therefore, a severe graded (30 g, 40 g and 50 g) weight-compression SCI at the Th9 spinal segment, involving an acute mechanical impact followed by 15 min of persistent compression, was studied in adult female Wistar rats. Functional parameters, such as spontaneous recovery of motor hind limb and bladder emptying function, and the presence of hematuria were evaluated within 28 days of the post-traumatic period. The disruption of the blood-spinal cord barrier, measured by extravasated Evans Blue dye, was examined 24 h after the SCI, when maximum permeability occurs. At the end of the survival period, the degradation of gray and white matter associated with the formation of cystic cavities, and quantitative changes of glial structural proteins, such as GFAP, and integral components of axonal architecture, such as neurofilaments and myelin basic protein, were evaluated in the lesioned area of the spinal cord. Based on these functional and histological parameters, and taking the animal’s welfare into account, the 40 g weight can be considered as an upper limit for severe traumatic injury in this compression model.


Author(s):  
Hao Zhang ◽  
Alexander Younsi ◽  
Guoli Zheng ◽  
Mohamed Tail ◽  
Anna-Kathrin Harms ◽  
...  

Abstract Purpose The Sonic Hedgehog (Shh) pathway has been associated with a protective role after injury to the central nervous system (CNS). We, therefore, investigated the effects of intrathecal Shh-administration in the subacute phase after thoracic spinal cord injury (SCI) on secondary injury processes in rats. Methods Twenty-one Wistar rats were subjected to thoracic clip-contusion/compression SCI at T9. Animals were randomized into three treatment groups (Shh, Vehicle, Sham). Seven days after SCI, osmotic pumps were implanted for seven-day continuous intrathecal administration of Shh. Basso, Beattie and Bresnahan (BBB) score, Gridwalk test and bodyweight were weekly assessed. Animals were sacrificed six weeks after SCI and immunohistological analyses were conducted. The results were compared between groups and statistical analysis was performed (p < 0.05 was considered significant). Results The intrathecal administration of Shh led to significantly increased polarization of macrophages toward the anti-inflammatory M2-phenotype, significantly decreased T-lymphocytic invasion and significantly reduced resident microglia six weeks after the injury. Reactive astrogliosis was also significantly reduced while changes in size of the posttraumatic cyst as well as the overall macrophagic infiltration, although reduced, remained insignificant. Finally, with the administration of Shh, gain of bodyweight (216.6 ± 3.65 g vs. 230.4 ± 5.477 g; p = 0.0111) and BBB score (8.2 ± 0.2 vs. 5.9 ± 0.7 points; p = 0.0365) were significantly improved compared to untreated animals six weeks after SCI as well. Conclusion Intrathecal Shh-administration showed neuroprotective effects with attenuated neuroinflammation, reduced astrogliosis and improved functional recovery six weeks after severe contusion/compression SCI.


BMC Neurology ◽  
2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Fangfang Qu ◽  
Zhenzhen Qu ◽  
Yingqian Lv ◽  
Bo Song ◽  
Bailin Wu

Abstract Background Transverse myelitis (TM) is due to inflammatory spinal cord injury with bilateral neurologic involvement, which is sensory, motor, or autonomic in nature. It may be associated with autoimmune disease, vaccination, intoxication and infections. The most common infection cause of TM is Coxsackie virus and Mycoplasma pneumoniae. The cryptococcosis is rare. We present the case of disseminated cryptococcosis revealed by transverse myelitis in an immunocompetent 55-year-old male patient. The literature review is also stated. Case presentation The 55-year-old man suffered from gradual numbness, weakness in both lower limbs and finally paralyzed in the bed. The thoracic spine Computed tomography (CT) was normal, but multiple nodules in the lung were accidentally discovered. Thoracic Magnetic Resonance Imaging (MRI) showed diffused thoracic spinal cord thickening and extensively intramedullary T2 hyper intensity areas. Gadolinium contrast enhanced T1WI showed an intramedullary circle-enhanced nodule at 9th thoracic level. Diagnosis was made by histological examination of the bilateral lung biopsy. The patient was treated successfully with systemic amphotericin B liposome and fluconazole and intrathecal dexamethasone and amphotericin B liposome. Conclusions This is a patient with disseminated cryptococcosis involving the lung, spinal cord and adrenal glands, which is rare in the absence of immunodeficiency.


2019 ◽  
Vol 24 (1) ◽  
pp. 174-177 ◽  
Author(s):  
Masaaki Machino ◽  
Shiro Imagama ◽  
Keigo Ito ◽  
Kei Ando ◽  
Kazuyoshi Kobayashi ◽  
...  

Spine ◽  
2018 ◽  
Vol 43 (8) ◽  
pp. E442-E447 ◽  
Author(s):  
Asdrubal Falavigna ◽  
Manuela Peletti Figueiró ◽  
Pedro Guarise da Silva ◽  
Lucas Piccoli Conzatti ◽  
Elisa Braun Rizkalla ◽  
...  

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