Caloric Stimulation-induced Augmentation of H-Reflexes in Normal Subjects, but Not in Spinal Cord-injured Patients

Neurosurgery ◽  
1984 ◽  
Vol 14 (5) ◽  
pp. 562-566 ◽  
Author(s):  
Maureen Raffensperger ◽  
Donald H. York
Keyword(s):  
Spinal Cord ◽  
Clinical Signs ◽  
Normal Subjects ◽  
H Reflex ◽  
Reflex Amplitude ◽  
Caloric Stimulation ◽  
Cord Injury ◽  
Injured Patients ◽  
Ice Water ◽  
Spinal Cord Injured

Abstract This study examined the effects of ice water caloric stimulation on H-reflex amplitude in normal subjects and three complete spinal cord-injured patients. H-reflexes were obtained by stimulating the tibial nerve at the popliteal fossa and recording the H-response from the gastrocnemius muscle. All normal subjects who experienced nystagmus or vertigo demonstrated significant augmentation in H-reflex amplitude with ice water irrigation of the ear canal. In the three spinal cord-injured patients, there was no significant change of H-reflex with the ice water stimulus. The results suggest that descending tracts in the anterior spinal cord must be functional to demonstrate caloric augmentation of H-reflexes. In patients with spinal cord injury, it may be possible to predict the recovery of motor function using this test together with other clinical signs of neurological function.

Effects of conditioning cutaneomuscular stimulation on the soleus H-reflex in normal and spastic paretic subjects during walking and standing

1994 ◽  
Vol 72 (5) ◽  
pp. 2090-2104 ◽  
Author(s):  
J. Fung ◽  
H. Barbeau
Keyword(s):  
Spinal Cord ◽  
Statistical Significance ◽  
Conditioning Stimulus ◽  
Normal Subjects ◽  
H Reflex ◽  
Quiet Standing ◽  
Inhibitory Influence ◽  
Sensory Threshold ◽  
Injured Patients ◽  
Spinal Cord Injured

1. The modulation of the soleus H-reflex by a conditioning cutaneomuscular stimulation was investigated in 10 normal and 10 spastic paretic subjects who suffered from incomplete spinal cord lesions. The different motor tasks examined were standing, locomotion, and the maintenance of static limb postures to mimic critical gait events. The test soleus H-reflex was obtained by stimulating the tibial nerve in the popliteal fossa with a single 1-ms pulse at an intensity that produced a barely detectable M wave. The conditioning stimulus, consisting of an 11-ms train of three 1-ms pulses at 200 Hz, was delivered to the ipsilateral medial plantar arch, stimulating predominantly the medial plantar nerve, at an innocuous intensity of 2.5–3.0 X sensory threshold and at a conditioning-test delay of 45 ms. 2. During quiet standing, the H-reflex amplitude was inhibited only marginally by the conditioning cutaneomuscular stimulation, not reaching statistical significance in either the normal or spastic group of subjects. Although there was a trend of reflex inhibition in the normal subjects as the conditioning intensity was increased, a reversed trend of reflex facilitation was observed in the spastic patients. 3. During treadmill walking, the conditioned H-reflex was inhibited significantly during all phases in all the normal subjects and in one mildly impaired patient. In the moderately and severely impaired patients, cutaneomuscular stimulation selectively inhibited the soleus H-reflex in the early stance and swing phases, thereby producing a near normal phasic modulation pattern. Such modulatory effects were not present under static gait-mimicking conditions. 4. The task-specific and phase-dependent effects of cutaneomuscular stimulation on the soleus H-reflex in the spinal cord-injured patients revealed strong inhibitory influence on Ia afferents from cutaneomuscular inputs. It is plausible that inhibition occurs at both pre- and postsynaptic levels. 5. It is concluded that normal Ia modulatory mechanisms during locomotion are deficient in spastic spinal cord-injured patients and can partially and artificially be restored by cutaneomuscular stimulation applied to the sole of the foot. This can be used as a functional electrical stimulation (FES) regime in gait rehabilitation.

scholarly journals Effect of cervicolumbar coupling on spinal reflexes during cycling after incomplete spinal cord injury

2018 ◽  
Vol 120 (6) ◽  
pp. 3172-3186 ◽  
Author(s):  
R. Zhou ◽  
B. Parhizi ◽  
J. Assh ◽  
L. Alvarado ◽  
R. Ogilvie ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
H Reflex ◽  
Spinal Reflexes ◽  
Incomplete Spinal Cord Injury ◽  
Reflex Amplitude ◽  
Arm Cycling ◽  
Cord Injury ◽  
Leg Cycling ◽  
Cycling Training

Spinal networks in the cervical and lumbar cord are actively coupled during locomotion to coordinate arm and leg activity. The goals of this project were to investigate the intersegmental cervicolumbar connectivity during cycling after incomplete spinal cord injury (iSCI) and to assess the effect of rehabilitation training on improving reflex modulation mediated by cervicolumbar pathways. Two studies were conducted. In the first, 22 neurologically intact (NI) people and 10 people with chronic iSCI were recruited. The change in H-reflex amplitude in flexor carpi radialis (FCR) during leg cycling and H-reflex amplitude in soleus (SOL) during arm cycling were investigated. In the second study, two groups of participants with chronic iSCI underwent 12 wk of cycling training: one performed combined arm and leg cycling (A&L) and the other legs only cycling (Leg). The effect of training paradigm on the amplitude of the SOL H-reflex was assessed. Significant reduction in the amplitude of both FCR and SOL H-reflexes during dynamic cycling of the opposite limbs was found in NI participants but not in participants with iSCI. Nonetheless, there was a significant reduction in the SOL H-reflex during dynamic arm cycling in iSCI participants after training. Substantial improvements in SOL H-reflex properties were found in the A&L group after training. The results demonstrate that cervicolumbar modulation during rhythmic movements is disrupted in people with chronic iSCI; however, this modulation is restored after cycling training. Furthermore, involvement of the arms simultaneously with the legs during training may better regulate the leg spinal reflexes.NEW & NOTEWORTHY This work systematically demonstrates the disruptive effect of incomplete spinal cord injury on cervicolumbar coupling during rhythmic locomotor movements. It also shows that the impaired cervicolumbar coupling could be significantly restored after cycling training. Actively engaging the arms in rehabilitation paradigms for the improvement of walking substantially regulates the excitability of the lumbar spinal networks. The resulting regulation may be better than that obtained by interventions that focus on training of the legs only.

scholarly journals Psychiatric aspects of spinal cord injury

1986 ◽  
Vol 42 (4) ◽  
pp. 113-114
Author(s):  
A. J. Lasich
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Emotional Reactions ◽  
Cord Injury ◽  
Injured Patients ◽  
Spinal Cord Injured

The nature of behavioural and emotional reactions displayed by persons with spinal cord injury are described and the value of psychiatric involvement in the routine management is discussed. The importance of emotional care of spinal cord injured patients is emphasized with reference to certain general principles. The psychiatrist should be accessible to both staff and patients for ventilation of feelings. 

scholarly journals Epidemiolgy of spinal cord injury after acute odontoid fractures

2000 ◽  
Vol 8 (6) ◽  
pp. 1-4 ◽  
Author(s):  
James S. Harrop ◽  
Ashwini D. Sharan ◽  
Gregory J. Przybylski
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Cervical Spinal Cord ◽  
Consecutive Series ◽  
Cervical Canal ◽  
Associated Injuries ◽  
Odontoid Fractures ◽  
Cord Injury ◽  
Injured Patients ◽  
Spinal Cord Injured

Object Cervical spinal cord injury (SCI) after odontoid fracture is unusual. To identify predisposing factors, the authors evaluated a consecutive series of patients who sustained SCI from odontoid fractures. Methods A consecutive series of 5096 admissions to the Delaware Valley Regional Spinal Cord Injury Center were reviewed, and 126 patients with neurological impairment at the C1–3 levels were identified. Seventeen patients had acute closed odontoid fractures with neurological deficit. Various parameters including demographics, mechanisms of injury, associated injuries, fracture types/displacements, and radiographic cervical canal dimensions were compared between “complete” and “incomplete” spinal cord injured–patients as well as with neurologically intact patients who had suffered odontoid fractures. There were similar demographics, mechanisms of injury, associated injuries, fracture type/displacement, and canal dimensions in patients with complete and incomplete SCIs. However, only patients with complete injury were ventilator dependent. In comparison with patients with intact spinal cords, spinal cord–injured patients were more commonly males (p = 0.011) who had sustained higher velocity injuries (p = 0.027). The computerized tomography scans of 11 of 17 neurologically impaired patients were compared with those of a random sample of 11 patients with intact spinal cords. Although the anteroposterior diameter (p = 0.028) and cross-sectional area (p = 0.0004) of the cervical spinal canal at the C–2 level were smaller in impaired patients, the displacement of the fragment was not different. Conclusions Odontoid fractures are an infrequent cause of SCI. Patients with these injuries typically are males who have smaller spinal canals and have sustained high velocity injuries.

scholarly journals Persistent beneficial impact of H-reflex conditioning in spinal cord-injured rats

2014 ◽  
Vol 112 (10) ◽  
pp. 2374-2381 ◽  
Author(s):  
Yi Chen ◽  
Lu Chen ◽  
Yu Wang ◽  
Jonathan R. Wolpaw ◽  
Xiang Yang Chen
Keyword(s):  
Spinal Cord ◽  
H Reflex ◽  
Spinal Reflex ◽  
Spinal Cord Regeneration ◽  
Lateral Column ◽  
Beneficial Effects ◽  
Cord Injury ◽  
Beneficial Impact ◽  
The Right ◽  
Spinal Cord Injured

Operant conditioning of a spinal cord reflex can improve locomotion in rats and humans with incomplete spinal cord injury. This study examined the persistence of its beneficial effects. In rats in which a right lateral column contusion injury had produced asymmetric locomotion, up-conditioning of the right soleus H-reflex eliminated the asymmetry while down-conditioning had no effect. After the 50-day conditioning period ended, the H-reflex was monitored for 100 [±9 (SD)] (range 79–108) more days and locomotion was then reevaluated. After conditioning ended in up-conditioned rats, the H-reflex continued to increase, and locomotion continued to improve. In down-conditioned rats, the H-reflex decrease gradually disappeared after conditioning ended, and locomotion at the end of data collection remained as impaired as it had been before and immediately after down-conditioning. The persistence (and further progression) of H-reflex increase but not H-reflex decrease in these spinal cord-injured rats is consistent with the fact that up-conditioning improved their locomotion while down-conditioning did not. That is, even after up-conditioning ended, the up-conditioned H-reflex pathway remained adaptive because it improved locomotion. The persistence and further enhancement of the locomotor improvement indicates that spinal reflex conditioning protocols might supplement current therapies and enhance neurorehabilitation. They may be especially useful when significant spinal cord regeneration becomes possible and precise methods for retraining the regenerated spinal cord are needed.

scholarly journals CLUSTER STRUCTURE OF FUNCTIONAL NETWORKS ESTIMATED FROM HIGH-RESOLUTION EEG DATA

2009 ◽  
Vol 19 (02) ◽  
pp. 665-676 ◽  
Author(s):  
ROBERTA SINATRA ◽  
FABRIZIO DE VICO FALLANI ◽  
LAURA ASTOLFI ◽  
FABIO BABILONI ◽  
FEBO CINCOTTI ◽  
...  
Keyword(s):  
Spinal Cord ◽  
High Resolution ◽  
Healthy Subjects ◽  
Cluster Structure ◽  
Cord Injury ◽  
Injured Patients ◽  
Global And Local ◽  
Spinal Cord Injured ◽  
Motor Areas ◽  
High Resolution Eeg

We study the topological properties of functional connectivity patterns among cortical areas in the frequency domain. The cortical networks were estimated from high-resolution EEG recordings in a group of spinal cord injured patients and in a group of healthy subjects, during the preparation of a limb movement. We first evaluate global and local efficiency, as indicators of the structural connectivity respectively at a global and local scale. Then, we use the Markov Clustering method to analyze the division of the network into community structures. The results indicate large differences between the injured patients and the healthy subjects. In particular, the networks of spinal cord injured patient exhibited a higher density of efficient clusters. In the Alpha (7–12 Hz) frequency band, the two observed largest communities were mainly composed of the cingulate motor areas with the supplementary motor areas, and of the premotor areas with the right primary motor area of the foot. This functional separation strengthens the hypothesis of a compensative mechanism due to the partial alteration in the primary motor areas because of the effects of the spinal cord injury.

The Effect of Therapeutic Massage on H-Reflex Amplitude in Persons With a Spinal Cord Injury

1994 ◽  
Vol 74 (8) ◽  
pp. 728-737 ◽  
Author(s):  
Joanne Goldberg ◽  
Derek E Seaborne ◽  
S John Sullivan ◽  
Bernard E Leduc
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
H Reflex ◽  
Reflex Amplitude ◽  
Therapeutic Massage ◽  
Cord Injury

Lower Extremity Functional Neuromuscular Stimulation in Cases of Spinal Cord Injury

Neurosurgery ◽  
1984 ◽  
Vol 15 (1) ◽  
pp. 132-146 ◽  
Author(s):  
George R. Cybulski ◽  
Richard D. Penn ◽  
Robert J. Jaeger
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Lower Extremity ◽  
Current Status ◽  
Functional Neuromuscular Stimulation ◽  
Neuromuscular Stimulation ◽  
Cord Injury ◽  
Practical Tool ◽  
Injured Patients ◽  
Spinal Cord Injured

Abstract Functional neuromuscular stimulation (FNS) provides a mechanism for the activation of muscles paralyzed by injury to the spinal cord. Although this technique was first used to treat patients with spinal cord injury over 20 years ago, only recent advances in electronics and biomechanics have made it a promising aid for the rehabilitation of these patients. Thus far, restoration of palmar prehension and lateral prehension in quadriplegics and of standing and biped gait in paraplegics has been achieved under carefully controlled laboratory conditions. This article reviews the current status of FNS and its potential as a practical tool to aid spinal cord-injured patients. Neurosurgeons who care for these patients might be expected to be involved in the future use of FNS if implantable systems are developed and tested.

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