Electrotherapeutic techniques

Neuromuscular electrical stimulation (NMES) is a commonly used intervention in rehabilitation programs for increasing muscle mass and force in individuals with partial loss of motor function, such as following spinal cord injury. 1, Functional electrical stimulation (FES) is a type ofNMES with the means of producing useful movement and may be used to assist in the performance of a functional task in paralysed muscles. However, both terms NMES and FES are usually utilised interchangeably in the literature, a pattern which will be followed throughout this chapter

Comprehensive and person-centred approach in research: What is missing?

The concept of a comprehensive and person-centred approach in healthcare is not new and it is the basic principle that is embedded in the International Classification of Functioning, Disability and Health (ICF) framework. However, the implementation of a comprehensive and person-centred approach has not been fully translated into research development in people living with spinal cord injuries (SCI). This approach in research is important as the perspectives of persons living with SCI should be equally valued drivers in any research intended to provide a direct or indirect outcome to people living with a SCI. This perspective paper will discuss some of the limiting factors and provide some examples of previous and current successful steps being taken towards the worldwide implementation of this approach. Finally, this paper will suggest some of the steps needed to implement this person-centred model in research in people with SCI

Effects of neuromuscular electrical stimulation in people with spinal cord injury

INTRODUCTION: Muscle force production is usually impaired in people with spinal cord injury (SCI). The use of high-intensity neuromuscular electrical stimulation (NMES) strength training can help promote metabolically active lean muscle mass and thus, increase muscle mass and improve physical health and quality of life (QoL). Nonetheless, NMES is usually used at low-stimulation intensities and there is limited evidence on the effects of high-intensity NMES strength training into improving muscle force and mass, symptoms of spasticity or physical health and quality of life (QoL) in people with SCI. METHODS: Five individuals with chronic SCI completed five 10-repetition sets of high-intensity knee extension NMES strength training sessions for 12 weeks in both quadriceps muscles. Quadriceps femoris (QF) knee extensor torque was measured on a dynamometer and cross-sectional area (CSAQF) was measured with extended-field-of-view ultrasonography. Venous blood samples were collected for blood lipid profiling and c-reactive protein (CRP) analyses. The Spinal Cord Injury Spasticity Evaluation Tool (SCI-SET) was used to assess symptoms of spasticity and the quality of life index (QLI) SCI version III was used for QoL measures. RESULTS: QF tetanic knee extensor torque increased on average by 35% (2 - 92%) and CSAQF increased by 47% (14 - 145%). A significant increase in the HDL/LDL cholesterol ratio (p < 0.001), a mean significant improvement of 4.8% ± 2.3% (absolute value = 0.26) in SCI-SET score was observed, whilst QoL showed a near-significant improvement in the health & functioning domain (15.0 ± 4.2; 17.3 ± 5.1; p = 0.07). CONCLUSIONS: High-intensity NMES-strength training in people with SCI may improve muscle strength, mass, physical health and QoL. However, replication of these results is necessary before clinical implementation

The effects of electrical stimulation parameters in managing spasticity after spinal cord injury: A systematic review

Controversial findings about the effects of neuromuscular electrical stimulation (NMES) and functional electrical stimulation (FES) in managing spasticity have been raised after spinal cord injury (SCI). A systematic review was conducted to identify the range of the stimulation parameters that may alleviate spasticity. Three independent reviewers searched Medline (PubMed), web of knowledge, Scopus, Cochrane Central, Virtual Health Library and Physiotherapy Evidence Database until January 2018. Inclusion criteria were applications of NMES/FES on the lower extremity muscles, stimulation parameters (frequency, pulse duration and amplitude of current) and measures of spasticity after SCI. The primary outcome was spasticity as measured by the Modified Ashworth Scale and the secondary outcome was spasticity assessed by other indirect measures. Twenty-three clinical and non-clinical trials were included with 389 subjects. NMES/FES provided reductions in spasticity by 45-60% with decrease in electromyography activity and increase in range of motion after SCI. The identified stimulation parameters were frequency of 20-30Hz, pulse duration of 300-350 μs and amplitude of the current > 100 mA. NMES/FES provides an effective rehabilitation strategy in managing spasticity. However, a recommendation of the stimulation parameters cannot be accurately assumed due to high variability in the methodology, design and heterogeneity of the included studies

Can combined aerobic and muscle strength training improve aerobic fitness, muscle strength, function and quality of life in people with spinal cord injury? A systematic review

Study design: A systematic review. Objectives: The aim of this systematic review was to establish whether combined aerobic training and muscle strength training is effective in improving aerobic fitness, muscle strength, function and/or quality of life (QoL) in people with spinal cord injury (SCI). Settings: Faculty of Health Sciences. University of Sydney, NSW, Australia. Methods: A search was conducted for randomized controlled trials (RCTs), controlled trials, uncontrolled clinical trials, case series and cross-over studies involving exercise interventions that included a combination of aerobic and strength components, either in circuit-mode or in sequence for people with SCI. Methodological quality was independently rated using the PEDro scale and key findings were extracted from trials by two reviewers. Results: The search identified 7981 abstracts, from which nine trials met the inclusion criteria. From the nine selected trials, seven reported aerobic outcomes, two of which showed a statistically significant within-group difference in aerobic fitness. Five studies reported muscle strength outcomes, four of them showed a statistically significant within-group mean difference on at least one outcome measure. Two studies looked at QoL, one of them found a statistically significant between-group difference on one outcome measure. Conclusion: Our systematic review showed that literature on SCI population is scarce, of low quality and findings of existing studies are inconsistent. Thus, further RCTs with larger number of participants are needed to make a definite conclusion about the influence of combined aerobic and muscle strength training on aerobic fitness, muscle strength and QoL in people with SCI. © 2015 International Spinal Cord Society

Effect of tendon vibration during wide-pulse neuromuscular electrical stimulation (NMES) on the decline and recovery of muscle force

© 2017 The Author(s). Background: Neuromuscular electrical stimulation (NMES) is commonly used to activate skeletal muscles and reverse muscle atrophy in clinical populations. Clinical recommendations for NMES suggest the use of short pulse widths (100-200 μs) and low-to-moderate pulse frequencies (30-50 Hz). However, this type of NMES causes rapid muscle fatigue due to the (non-physiological) high stimulation intensities and non-orderly recruitment of motor units. The use of both wide pulse widths (1000 μs) and tendon vibration might optimize motor unit activation through spinal reflex pathways and thus delay the onset of muscle fatigue, increasing muscle force and mass. Thus, the objective of this study was to examine the acute effects of patellar tendon vibration superimposed onto wide-pulse width (1000 μs) knee extensor electrical stimulation (NMES, 30 Hz) on peak muscle force, total impulse before "muscle fatigue", and the post-exercise recovery of muscle function. Methods: Tendon vibration (Vib), NMES (STIM) or NMES superimposed onto vibration (STIM + Vib) were applied in separate sessions to 16 healthy adults. Total torque-time integral (TTI), maximal voluntary contraction torque (MVIC) and indirect measures of muscle damage were tested before, immediately after, 1 h and 48 h after each stimulus. Results: TTI increased (145.0 ± 127.7%) in STIM only for "positive responders" to the tendon vibration (8/16 subjects), but decreased in "negative responders" (-43.5 ± 25.7%). MVIC (-8.7%) and rectus femoris electromyography (RF EMG) (-16.7%) decreased after STIM (group effect) for at least 1 h, but not after STIM + Vib. No changes were detected in indirect markers of muscle damage in any condition. Conclusions: Tendon vibration superimposed onto wide-pulse width NMES increased TTI only in 8 of 16 subjects, but reduced voluntary force loss (fatigue) ubiquitously. Negative responders to tendon vibration may derive greater benefit from wide-pulse width NMES alone

Invasive and non-invasive approaches of electrical stimulation to improve physical functioning after spinal cord injury

This review of literature provides the latest evidence involving invasive and non-invasive uses of electrical stimulation therapies that assist in restoring functional abilities and the enhancement of quality of life in those with spinal cord injuries. The review includes neuromuscular electrical stimulation and functional electrical stimulation activities that promote improved body composition changes and increased muscular strength, which have been shown to improve abilities in activities of daily living. Recommendations for optimizing electrical stimulation parameters are also reported. Electrical stimulation is also used to enhance the skills of reaching, grasping, standing, and walking, among other activities of daily living. Additionally, we report on the use of invasive and non-invasive neuromodulation techniques targeting improved mobility, including standing, postural control, and assisted walking. We attempt to summarize the effects of epidural stimulation on cardiovascular performance and provide a mechanistic explanation to the current research findings. Future trends such as the combination of epidural stimulation and exoskeletal-assisted walking are also discussed

Fatigue level in spinal cord injury AIS D community ambulatory subjects

Study design: Cross-sectional study. Objectives: The objective of our study was to determine the level of fatigue in ASIA impairment scale (AIS) D spinal cord injury (SCI) in community ambulatory subjects and correlate fatigue with other clinical symptoms. Setting: Outpatient Rehabilitation Unit, FLENI Institute, Escobar. Buenos Aires, Argentina. Methods: We included twenty-six patients with AIS D SCI that attended therapies at FLENI Institute between 2002 and 2009. We measured the demographic and clinical characteristics of the subjects. All patients were administered the fatigue severity scale (FSS). A cut-score for over four was indicative of significant fatigue. We used the Spearman's coefficient correlation to analyze associations among the FSS with pain (Visual analog scale), depression (Beck depression inventory), and physical activity (hours per week). Results: The median score of the FSS scale was 2.82 (1-5). Fatigue was found in 5 individuals (19.2%). There was a significant correlation between FSS scale and the Beck questionnaire. No association was found between FSS and pain or physical activity. Conclusion: The findings of this study suggest that fatigue is a relevant problem for people with SCI AIS D, and is a disabling symptom when present. There is a significant relationship between fatigue and depression. Sponsorship: FLENI Rehabilitation Institute. © 2012 International Spinal Cord Society All rights reserved

Effect of tendon vibration during wide-pulse neuromuscular electrical stimulation (NMES) on muscle force production in people with spinal cord injury (SCI)

Background: Neuromuscular electrical stimulation (NMES) is commonly used in skeletal muscles in people with spinal cord injury (SCI) with the aim of increasing muscle recruitment and thus muscle force production. NMES has been conventionally used in clinical practice as functional electrical stimulation (FES), using low levels of evoked force that cannot optimally stimulate muscular strength and mass improvements, and thus trigger musculoskeletal changes in paralysed muscles. The use of high intensity intermittent NMES training using wide-pulse width and moderate-intensity as a strength training tool could be a promising method to increase muscle force production in people with SCI. However, this type of protocol has not been clinically adopted because it may generate rapid muscle fatigue and thus prevent the performance of repeated high-intensity muscular contractions in paralysed muscles. Moreover, superimposing patellar tendon vibration onto the wide-pulse width NMES has been shown to elicit further increases in impulse or, at least, reduce the rate of fatigue in repeated contractions in able-bodied populations, but there is a lack of evidence to support this argument in people with SCI. Methods: Nine people with SCI received two NMES protocols with and without superimposing patellar tendon vibration on different days (i.e. STIM and STIM+vib), which consisted of repeated 30Hz trains of 58 wide-pulse width (1000μs) symmetric biphasic pulses (0.033-s inter-pulse interval; 2s stimulation train; 2-s inter-train interval) being delivered to the dominant quadriceps femoris. Starting torque was 20% of maximal doublet-twitch torque and stimulations continued until torque declined to 50% of the starting torque. Total knee extensor impulse was calculated as the primary outcome variable. Results: Total knee extensor impulse increased in four subjects when patellar tendon vibration was imposed (59.2±15.8%) but decreased in five subjects (-31.3±25.7%). However, there were no statistically significant differences between these sub-groups or between conditions when the data were pooled. Conclusions: Based on the present results there is insufficient evidence to conclude that patellar tendon vibration provides a clear benefit to muscle force production or delays muscle fatigue during wide-pulse width, moderate-intensity NMES in people with SCI. © 2018 The Author(s)

Plantar flexor muscle stretching depresses the soleus late response but not tendon tap reflexes

The purpose of this study was to investigate changes in muscle spindle sensitivity with early and late soleus reflex responses via tendon taps and transcranial magnetic stimulation, respectively, after an acute bout of prolonged static plantar flexor muscle stretching. Seventeen healthy males were tested before and after 5 min (5 × 60-s stretches) of passive static stretching of the plantar flexor muscles. Maximal voluntary isometric torque and M wave-normalized triceps surae muscle surface electromyographic activity were recorded. Both soleus tendon reflexes, evoked by percussion of the Achilles tendon during rest and transcranial magnetic stimulation-evoked soleus late responses during submaximal isometric dorsiflexion were also quantified. Significant decreases in maximal voluntary isometric plantar flexion torque (−19.2 ± 13.6%, p =.002) and soleus electromyographic activity (−20.1 ± 11.4%, p .05). Significant reductions in soleus late response amplitudes (−46.9 ± 36.0%, p =.002) were detected, although these changes were not correlated with changes in maximal electromyographic activity, torque or tendon reflex amplitudes. No changes in soleus late response latency were detected. In conclusion, impaired neural drive was implicated in the stretch-induced force loss; however, no evidence was found that this loss was related to changes in muscle spindle sensitivity. We hypothesize that the decrease in soleus late response indicates a stretch-induced reduction in a polysynaptic postural reflex rather than spindle reflex sensitivity