Whole-body vibration improves walking function in individuals with spinal cord injury: a pilot study

Effects of Whole-Body Vibration on Ankle Control and Walking Speed in Individuals with Incomplete Spinal Cord Injury

BACKGROUND/OBJECTIVES

After spinal cord injury (SCI), poor dorsiflexor control and involuntary plantar-flexor contraction impair walking. As whole-body vibration (WBV) improves voluntary muscle activation and modulates reflex excitability, it may improve ankle control. In this study, the dosage effects of WBV on walking speed, dorsiflexion, and spinal reflex excitability were examined.

METHODS

Sixteen people with chronic motor-incomplete SCI participated in this randomized sham-control wash-in study. Two weeks of sham stimulation (wash-in phase) were followed by either 2 weeks of eight repetitions (short bout) or sixteen repetitions of WBV (long bout; intervention phase) per session. Walking speed, ankle angle at mid-swing, and low-frequency depression of the soleus H-reflex were measured before and after the wash-in phase and before and after the intervention phase.

RESULTS

A significant dosage effect of WBV was not observed on any of the measures of interest. There were no between-phase or within-phase differences in ankle angle during the swing phase or in low-frequency depression. When dosage groups were pooled together, there was a significant change in walking speed during the intervention phase (mean = 0.04 m/s, standard deviation = 0.06, p = 0.02). There was not a significant correlation between overall change in walking speed and dorsiflexion angle or low-frequency depression during the study.

CONCLUSIONS

Whole-body vibration did not have a dosage-dependent effect on dorsiflexion during the swing phase or on spinal reflex excitability. Future studies assessing the role of corticospinal tract (CST) descending drive on increased dorsiflexor ability and walking speed are warranted.

Post-stroke whole body vibration therapy alters the cerebral transcriptome to promote ischemic tolerance in middle-aged female rats

Low-frequency whole body vibration (WBV; 40 Hz) therapy after stroke reduces ischemic brain damage, motor, and cognitive deficits in middle-aged rats of both sexes. However, the underlying mechanisms responsible for WBV induced ischemic protections remain elusive. In the current study, we hypothesize that post-stroke WBV initiates transcriptional reprogramming in the cortex of middle-aged female rats which is responsible for the observed reduced stroke consequences. Middle-aged female Sprague-Dawley rats that remained in constant diestrus (reproductively senescent) were randomized to either sham or transient middle cerebral artery occlusion (tMCAO; 90 min) surgery. A day after induction of tMCAO, animals received either WBV or no-WBV treatment for 15 min twice a day for five days for a week. Post-treatment, cortical tissue was analyzed for gene expression using RNA sequencing (RNAseq) and gene enrichment analysis via Enrichr. The RNAseq data analysis revealed significant changes in gene expression due to WBV therapy and the differentially expressed genes are involved in variety of biological processes like neurogenesis, angiogenesis, excitotoxicity, and cell death. Specifically, observed significant up-regulation of 116 and down-regulation of 258 genes after WBV in tMCAO exposed rats as compared to the no-WBV group. The observed transcriptional reprogramming will identify the possible mechanism(s) responsible for post-stroke WBV conferred ischemic protection and future studies will be needed to confirm the role of the genes identified in the current study.

Is There a New Road to Spinal Cord Injury Rehabilitation? A Case Report about the Effects of Driving a Go-Kart on Muscle Spasticity

BACKGROUND

Traumatic spinal cord injury (SCI) is a neurological disorder that causes a traumatic anatomical discontinuity of the spinal cord. SCI can lead to paraplegia, spastic, or motor impairments. Go-karting for people with SCI is an adapted sport that is becoming increasingly popular. The purpose of this case report is to shed light on the effects of driving a go-kart on a patient with SCI-related spasticity and to deepen understanding of the possible related role of whole-body vibration (WBV) and neuroendocrine reaction.

METHODS

The patient was a 50-year-old male with a spastic paraplegia due to traumatic SCI. He regularly practiced go-kart racing, reporting a transient reduction in spasticity. He was evaluated before (T0), immediately after (T1), 2 weeks after (T2), and 4 weeks after (T3) a go-kart driving session. On both sides, long adductor, femoral bicep, and medial and lateral gastrocnemius spasticity was assessed using the Modified Ashworth Scale (MAS), and tone and stiffness were assessed using MyotonPro.

RESULTS

It was observed that a go-kart driving session could reduce muscle spasticity, tone, and stiffness.

CONCLUSIONS

Go-kart driving can be a valid tool to obtain results similar to those of WBV and hormone production in the reduction of spasticity.

The acute effects of whole-body vibration on motor unit recruitment and discharge properties

Introduction: several studies have reported improved neuromuscular parameters in response to whole-body vibration (WBV). This is likely achieved by modulation of the central nervous system (CNS). Reduced recruitment threshold (RT), which is the % of Maximal Voluntary Force (%MVF) at which a given Motor Unit (MU) is recruited, may be responsible for the force/power improvements observed in several studies. Methods: 14 men (25 ± 2.3 years; BMI = 23.3 ± 1.5 kg m² MVF: 319.82 ± 45.74 N) performed trapezoidal isometric contractions of the tibialis anterior (TA) at 35-50-70 %MVF before and after three conditions: WBV, STAND (standing posture), and CNT (no intervention). The vibration was applied through a platform for targeting the TA. High-density surface electromyography (HDsEMG) recordings and analysis were used to detect changes in the RT and Discharge Rate (DR) of the MUs. Results: Mean motor unit recruitment threshold (MURT) reached 32.04 ± 3.28 %MVF before and 31.2 ± 3.72 %MVF after WBV, with no significant differences between conditions (p > 0.05). Additionally, no significant changes were found in the mean motor unit discharge rate (before WBV: 21.11 ± 2.94 pps; after WBV: 21.19 ± 2.17 pps). Discussion: The present study showed no significant changes in motor unit properties at the base of neuromuscular changes documented in previous studies. Further investigations are needed to understand motor unit responses to different vibration protocols and the chronic effect of vibration exposure on motor control strategies.

A comparison of one year outcomes between standardized locomotor training and usual care after motor incomplete spinal cord injury: Community participation, quality of life and re-hospitalization

CONTEXT/OBJECTIVE

Spinal cord injury (SCI) often results in a significant loss of mobility and independence coinciding with reports of decreased quality of life (QOL), community participation, and medical complications often requiring re-hospitalization. Locomotor training (LT), the repetition of stepping-like patterning has shown beneficial effects for improving walking ability after motor incomplete SCI, but the potential impact of LT on psychosocial outcomes has not been well-established. The purpose of this study was to evaluate one year QOL, community participation and re-hospitalization outcomes between individuals who participated in a standardized LT program and those who received usual care (UC).

DESIGN/SETTING/PARTICIPANTS

A retrospective (nested case/control) analysis was completed using SCI Model Systems (SCIMS) data comparing one year post-injury outcomes between individuals with traumatic motor incomplete SCI who participated in standardized LT to those who received UC.

OUTCOME MEASURES

Outcomes compared include the following: Satisfaction with Life Scale (SWLS™), Craig Handicap Assessment and Reporting Technique-Short Form (CHART-SF™), and whether or not an individual was re-hospitalized during the first year of injury.

RESULTS

Statistically significant improvements for the LT group were found in the following outcomes: SWLS (P = 0.019); and CHART subscales [mobility (P = <0.001)]; occupation (P = 0.028); with small to medium effects sizes.

CONCLUSION

Individuals who completed a standardized LT intervention reported greater improvements in satisfaction with life, community participation, and fewer re-hospitalizations at one year post-injury in comparison to those who received UC. Future randomized controlled trials are needed to verify these findings.

Beneficial effects of whole-body vibration exercise for brain disorders in experimental studies with animal models: a systematic review

Brain disorders have been a health challenge and is increasing over the years. Early diagnosis and interventions are considered essential strategies to treat patients at risk of brain disease. Physical exercise has shown to be beneficial for patients with brain diseases. A type of exercise intervention known as whole-body vibration (WBV) exercise gained increasing interest. During WBV, mechanical vibrations, produced by a vibrating platform are transmitted, to the body. The purpose of the current review was to summarize the effects of WBV exercise on brain function and behavior in experimental studies with animal models. Searches were performed in EMBASE, PubMed, Scopus and Web of Science including publications from 1960 to July 2021, using the keywords "whole body vibration" AND (animal or mice or mouse or rat or rodent). From 1284 hits, 20 papers were selected. Rats were the main animal model used (75%) followed by mice (20%) and porcine model (5%), 16 studies used males species and 4 females. The risk of bias, accessed with the SYRCLE Risk of Bias tool, indicated that none of the studies fulfilled all methodological criteria, resulting in possible bias. Despite heterogeneity, the results suggest beneficial effects of WBV exercise on brain functioning, mainly related to motor performance, coordination, behavioral control, neuronal plasticity and synapse function. In conclusion, the findings observed in animal studies justifies continued clinical research regarding the effectiveness and potential of WBV for the treatment of various types of brain disorders such as trauma, developmental disorders, neurogenetic diseases and other neurological diseases.

Acceptability and impact on spasticity of a single session of upper extremity vibration in individuals with tetraplegia

STUDY DESIGN

Pre-post design; before and after vibration intervention.

OBJECTIVES

To explore effect of a focal, self-applied upper extremity (UE) vibration intervention on UE spasticity for individuals with tetraplegia. The secondary objectives were to explore the acceptability and ease of use of this intervention.

SETTING

Specialty rehabilitation center in Georgia, USA.

METHODS

Eleven participants each completed one session of focal, self-applied vibration to the UEs. UE spasticity was measured using the Modified Ashworth Scale (MAS). UE function was measured using the Box & Block (B&B) test which measures the effectiveness of grasp, transport, and release. These measurements were taken pre-intervention, immediately post-intervention, and 20 min post-intervention. Participants also self-reported the acceptability and usability of the intervention, their perception of change in their spasticity and completed the Qualities of Spasticity Questionnaire.

RESULTS

In the full group analysis of the spasticity measures, no significant effects were found. Subgroup analysis, however, indicated participants with higher spasticity demonstrated significantly more change on the MAS than the lower spasticity group. Analysis did not reveal any impact of the intervention on UE function as measured by the B&B. Ten out of eleven participants indicated that they agreed or strongly agreed that the intervention would be valuable to have at home.

CONCLUSIONS

Participants with higher spasticity demonstrated decreased spasticity after focal UE vibration, although there was no clear effect on grasp, transport and release function. Participants were satisfied with the intervention; most were able to use it independently and indicated it would be a valuable home intervention.

Acute whole-body vibration reduces post-activation depression in the triceps surae muscle

PURPOSE

Acute whole-body vibration (WBV) is known to enhance neuromuscular activation. Especially mechanisms which act presynaptically are discussed to be involved in this modulation, but evidence is still limited. Therefore, this study aimed to investigate if 2 min of WBV might impact the premotoneuronal mechanism of post-activation depression (PAD).

METHODS

PAD in m. soleus was assessed by paired-pulse stimulation in 28 healthy participants prior, 2 min, 4 min and 10 min after 2 min of side-alternating WBV (10 Hz, 2 mm). Methodologies involved electromyography (m. soleus, m. tibialis anterior) and goniometric recordings (ankle, knee joint). H-reflexes were elicited with peripheral nerve stimulation and assessed by means of conditioned H-reflexes (ISI 1 s, H_cond) versus control H-reflexes (ISI₁₀, H).

RESULTS

H_cond/H was significantly enhanced by +55% (2 min), +32% (4 min) and +35% (10 min) following WBV (P < 0.05). Baseline muscle activity and joint positions were shown to be reliable (Cronbach's α values >0.990) throughout the testing procedure.

CONCLUSION

Vibratory-induced spinal inhibition is accompanied by diminished PAD at the presynaptic terminals which interconnect the Ia afferents with the α-motoneuron. Functionally, the PAD reduction might explain enhanced motor performance following vibration therapy, but future studies will be needed to verify this assumption.

Spinal Cord Injury as a Model of Bone-Muscle Interactions: Therapeutic Implications From in vitro and in vivo Studies

Spinal cord injuries (SCIs) represent a variety of conditions related to the damage of the spinal cord with consequent musculoskeletal repercussions. The bone and muscle tissues share several catabolic pathways that lead to variable degrees of disability in SCI patients. In this review article, we provide a comprehensive characterization of the available treatment options targeting the skeleton and the bone in the setting of SCI. Among the pharmacological intervention, bisphosphonates, anti-sclerostin monoclonal antibodies, hydrogen sulfide, parathyroid hormone, and RANKL pathway inhibitors represent valuable options for treating bone alterations. Loss phenomena at the level of the muscle can be counteracted with testosterone, anabolic-androgenic steroids, and selective androgen receptor modulators. Exercise and physical therapy are valuable strategies to increase bone and muscle mass. Nutritional interventions could enhance SCI treatment, particularly in the setting of synergistic and multidisciplinary interventions, but there are no specific guidelines available to date. The development of multidisciplinary recommendations is required for a proper clinical management of SCI patients.

Acute Effects of Whole-Body Vibration on the Postural Organization of Gait Initiation in Young Adults and Elderly: A Randomized Sham Intervention Study

Whole-body vibration (WBV) is a training method that exposes the entire body to mechanical oscillations while standing erect or seated on a vibrating platform. This method is nowadays commonly used by clinicians to improve specific motor outcomes in various sub-populations such as elderly and young healthy adults, either sedentary or well-trained. The present study investigated the effects of acute WBV application on the balance control mechanisms during gait initiation (GI) in young healthy adults and elderly. It was hypothesized that the balance control mechanisms at play during gait initiation may compensate each other in case one or several components are perturbed following acute WBV application, so that postural stability and/or motor performance can be maintained or even improved. It is further hypothesized that this capacity of adaptation is altered with aging. Main results showed that the effects of acute WBV application on the GI postural organization depended on the age of participants. Specifically, a positive effect was observed on dynamic stability in the young adults, while no effect was observed in the elderly. An increased stance leg stiffness was also observed in the young adults only. The positive effect of WBV on dynamic stability was ascribed to an increase in the mediolateral amplitude of "anticipatory postural adjustments" following WBV application, which did overcompensate the potentially destabilizing effect of the increased stance leg stiffness. In elderly, no such anticipatory (nor corrective) postural adaptation was required since acute WBV application did not elicit any change in the stance leg stiffness. These results suggest that WBV application may be effective in improving dynamic stability but at the condition that participants are able to develop adaptive changes in balance control mechanisms, as did the young adults. Globally, these findings are thus in agreement with the hypothesis that balance control mechanisms are interdependent within the postural system, i.e., they may compensate each other in case one component (here the leg stiffness) is perturbed.

The Effect of Whole Body Vibration Treatment on Balance and Gait in Patients with Stroke

Introduction

In patients with neurological disorders Whole Body Vibration (WBV) has been reported to improve motor function. Our aim was to assess the effects of WBV on both balance and walking performance in adult stroke patients.

Methods

Forty three post-stroke patients were randomly divided into two groups. One would receive WBV therapy (WBV group) while the control group would not. All patients participated in a conventional rehabilitation program for three weeks while the vibration group also received WBV over the same period. Patients balance and walking performance were evaluated using the Berg Balance Scale (BBS), Timed Up and Go Test (TUG) and computerized gait analysis. All evaluations were performed before and after therapy.

Results

The median (range) age of all patients was 51.00 (18-66) years. The groups numbered 26 and 17 patients for the WBV and control groups respectively. After intervention, significant improvements were found in the WBV group for BBS score (p=0.004), TUG score (p=0.035), step length (p=0.004) and walking speed (p=0.031) when compared to the controls.

Conclusion

WBV is effective for the improvement of balance and gait performance in stroke patients.

Transcutaneous Spinal Cord Stimulation Induces Temporary Attenuation of Spasticity in Individuals with Spinal Cord Injury

Epidural spinal cord stimulation (SCS) is currently regarded as a breakthrough procedure for enabling movement after spinal cord injury (SCI), yet one of its original applications was for spinal spasticity. An emergent method that activates similar target neural structures non-invasively is transcutaneous SCS. Its clinical value for spasticity control would depend on inducing carry-over effects, because the surface-electrode-based approach cannot be applied chronically. We evaluated single-session effects of transcutaneous lumbar SCS in 12 individuals with SCI by a test-battery approach, before, immediately after and 2 h after intervention. Stimulation was applied for 30 min at 50 Hz with an intensity sub-threshold for eliciting reflexes in lower extremity muscles. The tests included evaluations of stretch-induced spasticity (Modified Ashworth Scale [MAS] sum score, pendulum test, electromyography-based evaluation of tonic stretch reflexes), clonus, cutaneous-input-evoked spasms, and the timed 10 m walk test. Across participants, the MAS sum score, clonus, and spasms were significantly reduced immediately after SCS, and all spasticity measures were improved 2 h post-intervention, with large effect sizes and including clinically meaningful improvements. The effect on walking speed varied across individuals. We further conducted a single-case multi-session study over 6 weeks to explore the applicability of transcutaneous SCS as a home-based therapy. Self-application of the intervention was successful; weekly evaluations suggested progressively improving therapeutic effects during the active period and carry-over effects for 7 days. Our results suggest that transcutaneous SCS can be a viable non-pharmacological option for managing spasticity, likely working through enhancing pre- and post-synaptic spinal inhibitory mechanisms, and may additionally serve to identify responders to treatments with epidural SCS.

Whole Body Vibration Methods with Survivors of Polio

The purpose of the original study was to examine the use of whole body vibration (WBV) on polio survivors with and without post-polio syndrome as a form of weight bearing exercise. The goal of this article is to highlight the strengths, limitations, and applications of the method used. Fifteen participants completed two intervention blocks with a wash-out period in between the blocks. Each block consisted of twice a week (four weeks) WBV interventions, progressing from 10 to 20 min per session. Low intensity (peak to peak displacement 4.53 mm, frequency 24 Hz, g force 2.21) and higher intensity (peak to peak displacement 8.82 mm, frequency 35 Hz, g force 2.76) WBV blocks were used. Pain severity significantly improved in both groups following higher intensity vibration. Walking speed significantly improved in the group who participated in higher intensity intervention first. No study-related adverse events occurred. Even though this population can be at risk of developing overuse-related muscle weakness, fatigue, or pain from excessive physical activity or exercise, the vibration intensity levels utilized did not cause significant muscle weakness, pain, fatigue, or sleep disturbances. Therefore, WBV appears to provide a safe method of weight bearing exercise for this population. Limitations included the lack of measurement of reflexes, muscular activity, or circulation, the difficulty in participant recruitment, and insufficient strength of some participants to stand in recommended position. Strengths included a standard, safe protocol with intentional monitoring of symptoms and the heterogeneity of the participants in their physical abilities. An application of the methods is the home use of WBV to reduce the barriers associated with going to a facility for weight bearing exercise for longer term interventions, and benefits for conditions such as osteoporosis, particularly for aging adults with mobility difficulties due to paralysis or weakness. Presented method may serve as a starting point in future studies.

Whole-body vibration improves ankle spasticity, balance, and walking ability in individuals with incomplete cervical spinal cord injury

OBJECTIVES

This study aimed to investigate the effects of whole-body vibration (WBV) training on ankle spasticity, balance, and walking ability in patients with incomplete spinal cord injury (iSCI) at cervical level.

METHODS

Twenty-eight patients with cervical iSCI were randomly assigned to WBV (n = 14) or control group (n = 14). WBV group received WBV training, while control group was treated with placebo-treatment. All interventions were given for 20-min, twice a day, 5-days a week for 8-weeks. The spasticity of ankle plantar-flexors was assessed by estimating passive resistive force using a hand-held dynamometer. Balance was analyzed based on postural sway length (PSL) using a force plate. Timed-Up and Go test (TUG) and 10 m-Walk Test (10MWT) were used to assess walking ability.

RESULTS

Both groups showed significant improvements in spasticity, balance and walking ability. Also, the significant differences between two groups were demonstrated in the outcomes of spasticity (3.0±1.7 vs 0.9±1.2), PSL (6.4±1.2 vs 3.2±0.9 with eyes-open, and 15.1±10.9 vs 7.4±4.3 with eyes-closed), TUG (2.3±1.3 vs 1.0±1.0), and 10MWT (3.5±2.3 vs 1.3±1.4).

CONCLUSIONS

WBV may be a safe and effective intervention to improve spasticity, balance and walking ability in individuals with cervical iSCI. Thus, WBV may be used to improve these symptoms in clinics.

Comparison of Single-Session Dose Response Effects of Whole Body Vibration on Spasticity and Walking Speed in Persons with Spinal Cord Injury

Spasticity affects approximately 65% of persons with spinal cord injury (SCI) and negatively impacts function and quality of life. Whole body vibration (WBV) appears to reduce spasticity and improve walking function; however, the optimal dose (frequency/duration) is not known. We compared single-session effects of four different WBV frequency/duration dose conditions on spasticity and walking speed, in preparation for a planned multi-session study. Thirty-five participants with motor-incomplete SCI received four different doses of WBV: high frequency (50 Hz)/short duration (180 s), high frequency/long duration (360 s), low frequency (30 Hz)/short duration, and low frequency/long duration, plus a control intervention consisting of sham electrical stimulation. In all conditions, participants stood on the WBV platform for 45-s bouts with 1 min rest between bouts until the requisite duration was achieved. The frequency/duration dose order was randomized across participants; sessions were separated by at least 1 week. Quadriceps spasticity was measured using the pendulum test at four time points during each session: before, immediately after, 15 min after, and 45 min after WBV. Walking speed was quantified using the 10-m walk test at three time points during each session: baseline, immediately after, and 45 min after WBV. In the full group analysis, no frequency/duration combination was significantly different from the sham-control condition. In participants with more severe spasticity, a greater reduction in stretch reflex excitability was associated with the high frequency/long duration WBV condition. The sham-control condition was associated with effects, indicating that the activity of repeated sitting and standing may have a beneficial influence on spasticity.

TRIAL REGISTRATION

NCT02340910 (assigned 01/19/2015).

Whole body vibration on people with sequelae of polio

PURPOSE

The purpose was to explore the feasibility of whole body vibration (WBV) on polio survivors with/without post-polio syndrome (PPS) by studying its effects on walking speed (10-m walk test), endurance (2-min walk test), pain severity/interference (Brief Pain Inventory [BPI]), sleep quality (Pittsburg Sleep Quality Index), fatigue (Fatigue Severity Scale), leg strength (manual muscle testing and hand-held dynamometry), and muscle cramping (written logs).

METHODS

Fifteen individuals completed the study, participating in eight sessions in two 4-week blocks. Participants started with ten 1-min vibration bouts/session, increasing to 20 min. Low (amplitude 4.53 mm, g force 2.21) and higher (amplitude 8.82 mm, g force 2.76) intensity blocked intervention occurred in random order crossover design. Blinded testing ensued before/after intervention blocks and at follow-up.

RESULTS

No study-related adverse events occurred. Participants starting first with higher intensity intervention improved in walking speed (p = 0.017). BPI pain severity significantly improved (p = 0.049) after higher intensity intervention. No significant changes were found after low intensity vibration or in other outcome measures.

CONCLUSIONS

WBV appears to be a safe exercise for this population. Long-term use in polio survivors needs to be researched, particularly in reducing barriers to participation to promote the physical aspects of health.

POTENTIAL EFFECTS OF WHOLE-BODY VIBRATION EXERCISES ON BLOOD FLOW KINETICS OF DIFFERENT POPULATIONS: A SYSTEMATIC REVIEW WITH A SUITABLE APPROACH

BACKGROUND

The ability to control skin blood flow decreases with advancing age and some clinical disorders, as in diabetes and in rheumatologic diseases. Feasible clinical strategies such as whole-body vibration exercise (WBVE) are being used without a clear understanding of its effects. The aim of the present study is to review the effects of the WBVE on blood flow kinetics and its feasibility in different populations.

MATERIAL AND METHODS

The level of evidence (LE) of selected papers in PubMed and/or PEDRo databases was determined. We selected randomized, controlled trials in English to be evaluated.

RESULTS

Six studies had LE II, one had LE III-2 and one III-3 according to the NHMRC. A great variability among the protocols was observed but also in the assessment devices; therefore, more research about this topic is warranted.

CONCLUSION

Despite the limitations, it is can be concluded that the use of WBVE has proven to be a safe and useful strategy to improve blood flow. However, more studies with greater methodological quality are needed to clearly define the more suitable protocols.

Gait-like vibration training improves gait abilities: a case report of a 62-year-old person with a chronic incomplete spinal cord injury

The purpose of this single-subject case study was to quantify the effect of gait-like vibration training on gait abilities after an incomplete spinal cord injury (SCI). A 62-year-old male with a chronic American Spinal Injury Association Impairment Scale D SCI at T11 completed nine sessions of gait-like vibration training in a standing position. Self-selected gait speed and distance covered within 6 min were determined before and after training to evaluate the impact of training on gait performance. Associated changes in gait kinematics were assessed with a three-dimensional motion analysis system. Results showed an improvement of gait speed (0.26 vs 0.35 m s^-1) and distance (23 vs 37 m) after nine gait-like vibration training sessions (+34.6%; +60.9%). In addition, more bilateral hip extension and larger left hip range of motion improved hip-knee cyclograms. Gait-like vibration training improved gait abilities in a person with chronic incomplete SCI.

Supraspinal Control Predicts Locomotor Function and Forecasts Responsiveness to Training after Spinal Cord Injury

Restoration of walking ability is an area of great interest in the rehabilitation of persons with spinal cord injury. Because many cortical, subcortical, and spinal neural centers contribute to locomotor function, it is important that intervention strategies be designed to target neural elements at all levels of the neuraxis that are important for walking ability. While to date most strategies have focused on activation of spinal circuits, more recent studies are investigating the value of engaging supraspinal circuits. Despite the apparent potential of pharmacological, biological, and genetic approaches, as yet none has proved more effective than physical therapeutic rehabilitation strategies. By making optimal use of the potential of the nervous system to respond to training, strategies can be developed that meet the unique needs of each person. To complement the development of optimal training interventions, it is valuable to have the ability to predict future walking function based on early clinical presentation, and to forecast responsiveness to training. A number of clinical prediction rules and association models based on common clinical measures have been developed with the intent, respectively, to predict future walking function based on early clinical presentation, and to delineate characteristics associated with responsiveness to training. Further, a number of variables that are correlated with walking function have been identified. Not surprisingly, most of these prediction rules, association models, and correlated variables incorporate measures of volitional lower extremity strength, illustrating the important influence of supraspinal centers in the production of walking behavior in humans.

Acute corticospinal and spinal modulation after whole body vibration

OBJECTIVES

The objective of this study was to investigate neural effects of acute whole body vibration (WBV) on lower limb muscles regarding corticospinal and spinal excitability.

METHODS

In 44 healthy subjects (16 f/ 28 m), motor evoked potentials (MEP) and H-reflexes in m. soleus (SOL) and gastrocnemius medialis (GM) were elicited before (t₁), immediately after (t₂), 2 (t₃), 4 (t₄) and 10 min after (t₅) WBV.

RESULTS

After WBV, MEP amplitudes were significantly increased in SOL (t₂+15±30%, t₃+22±32%, t₄+15±35%, t₅+20±30%, P<0.05), but not in GM (t₂+32±62%, t₃+9±35%, t₄+8±36%, t₅+22±47%; P=0.07). Contrarily, H-reflexes were significantly reduced in SOL (t₂-19±28%, t₃-21±22%, t₄-20±21%, t₅-14±28%, P<0.05) and GM (t₂-14±37%, t₃-16±25%, t₄-18±29%, t₅-16±28%, P<0.05).

CONCLUSIONS

A temporary sustained enhancement of corticospinal excitability concomitant with spinal inhibition after WBV points towards persisting neural modulation in the central nervous system. This could indicate greater neural modulation over M1 and descending pathways, while the contribution of spinal pathways is reduced.

Comparison of 2 Multimodal Interventions With and Without Whole Body Vibration Therapy Plus Traction on Pain and Disability in Patients With Nonspecific Chronic Low Back Pain

OBJECTIVE

The purpose of this secondary data analysis was to compare the effect of 2 multimodal exercise-based physical therapy interventions (one with and one without whole-body vibration [WBV] therapy plus traction) on pain and disability in patients with nonspecific chronic low back pain (NSCLBP).

METHODS

We conducted a secondary analysis of data from 2 distinct samples. One sample was from the Focus on Therapeutic Outcomes Inc. (FOTO) group (n = 55, age 55.1 ± 19.0 years), and the other was the Illinois Back Institute (IBI) (n = 70, age 47.5 ± 13.4 years). Both groups of patients had NSCLBP for more than 3 months and a pain numeric rating scale (NRS) score of ≥7. Both groups received treatment consisting of flexibility or stretching exercises, core stability training, functional training, and postural exercises and strengthening exercises. However, the IBI group also received WBV plus traction. NSCLBP was measured before and after therapeutic trials using the NRS for pain and Oswestry Disability Index (ODI).

RESULTS

The NRS scores were significantly improved in both groups, decreasing by 2 points in the FOTO group and by 5 points in the IBI group. The ODI scores were significantly improved in both groups; the FOTO group score improved by 9 points and the IBI group improved by 22 points.

CONCLUSIONS

The results of this preliminary study suggest that NPS and ODI scores statistically improved for both NSCLBP groups receiving multimodal care. However, the group that included WBV therapy plus traction in combination with multimodal care had greater clinical results. This study had several limitations making it difficult to generalize the results from this study sample to the entire population.

Effects of whole-body vibration on neuromuscular performance in individuals with spinal cord injury: a systematic review

OBJECTIVE

To examine the effects of whole-body vibration on neuromuscular performance in people with spinal cord injury and evaluate the safe and effective vibration protocols.

METHODS

PubMed, EMBASE, CINAHL and PEDro were mainly searched for English literatures. Other data sources were ClinicalTrials.gov , Current Controlled Trials and reference lists of all relevant articles. The PEDro scale was used to evaluate the methodological quality, and the Oxford Centre for Evidence-based Medicine level of evidence was used to assess the level of evidence. Basic information and whole-body vibration protocols were extracted by two independent researchers. Any disagreements were resolved by the third researcher.

RESULTS

Of the eight included studies involving 94 individuals with spinal cord injury and 24 able-bodied participants, six of them reported beneficial effects of whole-body vibration on muscle activation and the other two on muscle spasticity. Based on the reviewed studies, an intermittent mode of whole-body vibration (frequency: 10-50 Hz; amplitude: 0.6-4 mm) is less likely to cause adverse events when applying to spinal cord injury subjects standing on platform (knees flexed at 10°-40°).

CONCLUSIONS

The strength of evidence is insufficient in supporting the benefits of whole-body vibration on neuromuscular performance in individuals with spinal cord injury. The intermittent vibration (frequency: 10-50 Hz; amplitude: 0.6-4 mm; knee flexion: 10°-40°) may be the possible effective range and have good compliance.

Effects of vibratory training on plantar impression in patients affected by stroke

Aim:

The aim of this study was to investigate the effect of vibration training on plantar impression and motor function in patients affected by stroke.

Methods:

The sample consisted of 28 individuals with hemiparesis after stroke who were randomly assigned to the intervention group (n=18) and the control group (n=10). The instruments used for evaluation were the mini-mental state examination, photopodoscopy and the 6-minute walk test. For treatment, whole body vibration training was used three times a week for 8 weeks. The treatment was carried out in two phases. The first phase, which lasted for 4 weeks, consisted of four sets of exercises with 60 seconds of vibration. In the first exercise, the participants were in a static standing position, feet apart with knees flexed at 30°. In the second exercise, the same position was implemented, with knees flexed at 90°. In the third exercise, a standing position with one-leg support on the affected limb with flexed knee at 30°. The fourth exercise was a repetition of the first exercise. The second phase also lasted for 4 weeks. It consisted of the same exercises but the amount of sets of exercises was doubled.

Results:

Data were analysed by independent t-test and repeated measures ANOVA with two factors. There was no intergroup nor intragroup statistical difference (P=0.05) in the plantar impression area on the affected and unaffected side; there was only intragroup statistical differences in the 6-minute walk test (P=0.03).

Conclusions:

Whole-body vibration training did not influence the increase of the plantar impression area and motor function in stroke patients.

Single-dose effects of whole body vibration on quadriceps strength in individuals with motor-incomplete spinal cord injury

CONTEXT

Paresis associated with motor-incomplete spinal cord injury (SCI) impairs function. Whole body vibration (WBV) may increase strength by activating neuromuscular circuits.

OBJECTIVE

We assessed effects of a single session of WBV on lower extremity strength in individuals with motor-incomplete SCI.

DESIGN

A single-session blinded randomized controlled trial.

SETTING

Rehabilitation research laboratory.

PARTICIPANTS

Subjects (n = 25; age 49.7 ± 12.5 years) had chronic SCI (>1 year) and were able to stand for at least 45 seconds. Interventions Subjects were randomized either to WBV (n = 13) consisting of four 45-second bouts with 1-minute intervening rest periods (frequency: 50 Hz, amplitude: 2 mm) or to sham electrical stimulation (n = 12).

OUTCOME MEASURES

Maximal voluntary isometric quadriceps force was measured with a fixed dynamometer. A modified Five-Time-Sit-To-Stand (FTSTS) test was used to assess functional lower extremity strength. Measures were made at pre-test, immediate post-test, and delayed post-test 20 minutes later.

RESULTS

At immediate post-test, change in voluntary isometric force in the WBV group was 1.12 kg greater than in the sham group. The within-group change for the WBV group was significant with a moderate effect size (P = 0.05; ES = 0.60). No force-related changes were observed in the sham group. The modified FTSTS scores improved in both groups, suggesting that this measure was subject to practice effects.

CONCLUSION

Evidence from the present study suggests that even a single session of WBV is associated with a meaningful short-term increase in quadriceps force-generating capacity in persons with motor-incomplete SCI. The multi-session use of WBV as part of a strengthening program deserves exploration.

Road collisions as a cause of traumatic spinal cord injury in ireland, 2001-2010

BACKGROUND

Road collisions remain the leading cause of traumatic spinal cord injury (TSCI) in the world. Half of all TSCIs in Ireland in 2000 were caused by road collisions. Since then, there has been a downward trend in road fatalities coincident with implemented road safety strategies.

OBJECTIVE

To examine the incidence of TSCI resulting from road collisions from 2001 to 2010.

METHOD

This is a retrospective study using the hospital inpatient enquiry database of the tertiary referral center, which houses the national spinal injuries unit. Information retrieved included total numbers of patients with TSCI and number of TSCIs due to road collisions from 2001 through 2010, age groups affected, and the gender balance.

RESULTS

Over the 10-year period studied, the incidence rate of TSCI due to road collisions declined, although this did not reach statistical significance. The largest numbers of all TSCIs and TSCIs due to road collisions were in the 20- to 29-year age category and the male gender.

CONCLUSIONS

As mortality due to road collisions declined, so did the number of TSCIs from the same etiology. An impactful road safety campaign is likely to have influenced these trends.

Effects of vibration on spasticity in individuals with spinal cord injury: a scoping systematic review

The objective of this systematic review was to evaluate how whole-body vibration (WBV) or focal vibration (FV) would change spasticity in individuals with spinal cord injury (SCI). A search was conducted of MEDLINE, EMBASE, CINAHL, and PsycINFO electronic databases. A hand search was conducted of the bibliographies of articles and journals relevant to the research question. The inclusion criteria were three or more individuals, 17 yrs or older, with SCI who experience spasticity, and WBV or FV application. The evidence level of all ten identified studies (195 SCI subjects) was low on the basis of Centre for Evidence Based Medicine level of evidence. WBV (n = 1) and FV (n = 9) were applied to assess the effects of vibration on different measures of spasticity in individuals with SCI. FV application resulted in a short-term spasticity reduction lasting for a maximum of 24 hrs. Neurophysiologic measures showed H-reflex inhibition in individuals with SCI after FV application. WBV resulted in a decrease in spasticity lasting for 6-8 days after the last vibration session. WBV and FV might decrease spasticity for a short period, but no evidence-based recommendation can be drawn from the literature to guide rehabilitation medicine clinicians to manage spasticity with vibration application.

Whole body vibration exercises and the improvement of the flexibility in patient with metabolic syndrome

Vibrations produced in oscillating/vibratory platform generate whole body vibration (WBV) exercises, which are important in sports, as well as in treating diseases, promoting rehabilitation, and improving the quality of life. WBV exercises relevantly increase the muscle strength, muscle power, and the bone mineral density, as well as improving the postural control, the balance, and the gait. An important number of publications are found in the PubMed database with the keyword “flexibility” and eight of the analyzed papers involving WBV and flexibility reached a level of evidence II. The biggest distance between the third finger of the hand to the floor (DBTFF) of a patient with metabolic syndrome (MS) was found before the first session and was considered to be 100%. The percentages to the other measurements in the different sessions were determined to be related to the 100%. It is possible to see an immediate improvement after each session with a decrease of the %DBTFF. As the presence of MS is associated with poorer physical performance, a simple and safe protocol using WBV exercises promoted an improvement of the flexibility in a patient with MS.

Effect of whole-body vibration on lower-limb EMG activity in subjects with and without spinal cord injury

OBJECTIVE

Traumatic spinal cord injury (SCI) results in substantial reductions in lower extremity muscle mass and bone mineral density below the level of the lesion. Whole-body vibration (WBV) has been proposed as a means of counteracting or treating musculoskeletal degradation after chronic motor complete SCI. To ascertain how WBV might be used to augment muscle and bone mass, we investigated whether WBV could evoke lower extremity electromyography (EMG) activity in able-bodied individuals and individuals with SCI, and which vibration parameters produced the largest magnitude of effect.

METHODS

Ten male subjects participated in the study, six able-bodied and four with chronic SCI. Two different manufacturers' vibration platforms (WAVE(®) and Juvent™) were evaluated. The effects of vibration amplitude (0.2, 0.6 or 1.2 mm), vibration frequency (25, 35, or 45 Hz), and subject posture (knee angle of 140°, 160°, or 180°) on lower extremity EMG activation were determined (not all combinations of parameters were possible on both platforms). A novel signal processing technique was proposed to estimate the power of the EMG waveform while minimizing interference and artifacts from the plate vibration.

RESULTS

WBV can elicit EMG activity among subjects with chronic SCI, if appropriate vibration parameters are employed. The amplitude of vibration had the greatest influence on EMG activation, while the frequency of vibration had lesser but statistically significant impact on the measured lower extremity EMG activity.

CONCLUSION

These findings suggest that WBV with appropriate parameters may constitute a promising intervention to treat musculoskeletal degradation after chronic SCI.

Muscle activity, cross-sectional area, and density following passive standing and whole body vibration: A case series

OBJECTIVE

To investigate the effects of intermittent passive standing (PS) and whole body vibration (WBV) on the electromyography (EMG) activity, cross-sectional area, and density of lower extremity muscles in individuals with chronic motor complete spinal cord injury (SCI).

DESIGN

Case series.

METHODS

Seven adult men with chronic (≥2 years), thoracic motor complete (AIS A-B) SCI completed a 40-week course of thrice-weekly intermittent PS-WBV therapy, in a flexed knee posture (160°), for 45 minutes per session at a frequency of 45 Hz and 0.6-0.7 mm displacement using the WAVE(®) Pro Plate, with an integrated EasyStand™ standing frame. EMG was measured in major lower extremity muscles to represent muscle activity during PS-WBV. The cross-sectional area and density of the calf muscles were measured using peripheral quantitative computed tomography at the widest calf cross-section (66% of the tibia length) at pre- and post-intervention. All measured variables were compared between the pre- and post-intervention measurements to assess change after the PS-WBV intervention.

RESULTS

PS-WBV acutely induced EMG activity in lower extremity muscles of SCI subjects. No significant changes in lower extremity EMG activity, muscle cross-sectional area, or density were observed following the 40-week intervention.

CONCLUSIONS

Although acute exposure to PS-WBV can induce electrophysiological activity of lower extremity muscles during PS in men with motor complete SCI, the PS-WBV intervention for 40 weeks was not sufficient to result in enhanced muscle activity, or to increase calf muscle cross-sectional area or density.

Effects of low intensity vibration on bone and muscle in rats with spinal cord injury

Spinal cord injury (SCI) causes rapid and marked bone loss. The present study demonstrates that low-intensity vibration (LIV) improves selected biomarkers of bone turnover and gene expression and reduces osteoclastogenesis, suggesting that LIV may be expected to benefit to bone mass, resorption, and formation after SCI.

INTRODUCTION

Sublesional bone is rapidly and extensively lost following spinal cord injury (SCI). Low-intensity vibration (LIV) has been suggested to reduce loss of bone in children with disabilities and osteoporotic women, but its efficacy in SCI-related bone loss has not been tested. The purpose of this study was to characterize effects of LIV on bone and bone cells in an animal model of SCI.

METHODS

The effects of LIV initiated 28 days after SCI and provided for 15 min twice daily 5 days each week for 35 days were examined in female rats with moderate severity contusion injury of the mid-thoracic spinal cord.

RESULTS

Bone mineral density (BMD) of the distal femur and proximal tibia declined by 5 % and was not altered by LIV. Serum osteocalcin was reduced after SCI by 20 % and was increased by LIV to a level similar to that of control animals. The osteoclastogenic potential of bone marrow precursors was increased after SCI by twofold and associated with 30 % elevation in serum CTX. LIV reduced the osteoclastogenic potential of marrow precursors by 70 % but did not alter serum CTX. LIV completely reversed the twofold elevation in messenger RNA (mRNA) levels for SOST and the 40 % reduction in Runx2 mRNA in bone marrow stromal cells resulting from SCI.

CONCLUSION

The findings demonstrate an ability of LIV to improve selected biomarkers of bone turnover and gene expression and to reduce osteoclastogenesis. The study indicates a possibility that LIV initiated earlier after SCI and/or continued for a longer duration would increase bone mass.

Effects of whole-body vibration therapy on body functions and structures, activity, and participation poststroke: a systematic review

BACKGROUND

Whole-body vibration (WBV) has gained increasing popularity in rehabilitation. Recent studies have investigated the application of WBV in individuals with chronic illnesses, including stroke.

PURPOSE

The purpose of this study was to compare WBV exercise with the same exercise condition without WBV and with other types of physical exercise in enhancing body functions and structures, activity, and participation in individuals with stroke and examine its safety.

DATA SOURCE

Electronic searches were conducted on MEDLINE, CINAHL, PEDro, PubMed, PsycINFO, and Science Citation Index.

STUDY SELECTION

Randomized controlled trials (RCTs) that investigated the effects of WBV among individuals with stroke were identified by 2 independent researchers. Ten articles (9 studies, totaling 333 study participants) satisfied the selection criteria and were included in this review.

DATA EXTRACTION

The methodological quality was rated using the PEDro scale. The results were extracted by 2 independent researchers and confirmed with the principal investigator.

DATA SYNTHESIS

Only 2 RCTs were considered as demonstrating level 1 evidence (PEDro score ≥6 and sample size >50). Two RCTs examined the effects of a single WBV session, and 7 RCTs examined the effects of WBV programs spanning 3 to 12 weeks. No consistent benefits on bone turnover, leg motor function, balance, mobility, sensation, fall rate, activities of daily living, or societal participation were found, regardless of the nature of the comparison group. Adverse events were minor.

LIMITATIONS

A broad approach was used, with stroke as an inclusion criterion for review. No solid evidence was found concerning the effects of WBV on subgroups of people with specific stroke-related deficits due to the heterogeneity of patient groups.

CONCLUSIONS

Based on the review, there is insufficient evidence to support clinical use of WBV in enhancing body functions and structures, activity, and participation after stroke.

Whole body and local muscle vibration reduce artificially induced quadriceps arthrogenic inhibition

OBJECTIVE

To evaluate the effects of whole body vibration (WBV) and local muscle vibration (LMV) on quadriceps function after experimental knee effusion (ie, simulated pathology).

DESIGN

Randomized controlled trial.

SETTING

Research laboratory.

PARTICIPANTS

Healthy volunteers (N=43) were randomized to WBV (n=14), LMV (n=16), or control (n=13) groups.

INTERVENTIONS

Saline was injected into the knee to induce quadriceps arthrogenic muscle inhibition (AMI). All groups then performed isometric squats while being exposed to WBV, LMV, or no vibration (control).

MAIN OUTCOME MEASURES

Quadriceps function was assessed at baseline, immediately after effusion, and immediately and 5 minutes after each intervention (WBV, LMV, control) via voluntary peak torque (VPT) and the central activation ratio (CAR) during maximal isometric knee extension on a multifunction dynamometer.

RESULTS

The CAR improved in the WBV (11.4%, P=.021) and LMV (7.3%, P<.001) groups immediately postintervention, but they did not improve in the control group. Similarly, VPT increased by 16.5% (P=.021) in the WBV group and 23% (P=.078) in the LMV group immediately postintervention, but it did not increase in the control group. The magnitudes of improvements in the CAR and VPT did not differ between the WBV and LMV groups.

CONCLUSIONS

Quadriceps AMI is a common complication following knee pathology that produces quadriceps dysfunction and increases the risk of posttraumatic osteoarthritis. Quadriceps strengthening after knee pathology is often ineffective because of AMI. WBV and LMV improve quadriceps function equivocally after simulated knee pathology, effectively minimizing quadriceps AMI. Therefore, these stimuli may be used to enhance quadriceps strengthening, therefore improving the efficacy of rehabilitation and reducing the risk of osteoarthritis.

Training to achieve over ground walking after spinal cord injury: a review of who, what, when, and how

OBJECTIVES

(1) To provide clinicians with the best evidence for effective retraining of walking after spinal cord injury (SCI) to achieve over ground walking. (2) To identify gaps in our knowledge to guide future research.

METHODS

Articles that addressed the retraining of walking in adults with SCI and reported outcome measures of over ground walking ability were identified through a non-systematic search of the PubMed, Scopus, and CINAHL databases. No restriction was applied to the method of training. Selected articles were appraised using the Physiotherapy Evidence Database scale. Information was synthesized to answer who best responds to what type of treatment, how that treatment should be delivered, and at what stage after injury.

RESULTS

Individuals with motor incomplete SCI (American Spinal Injury Association (ASIA) Impairment scale (AIS) C and D) are most likely to regain walking over ground. The effective methods of training all involved a substantial component of walking in the training, and if assistance was provided, partial assistance was more effective than total assistance. Walking training resulted in a change in over ground walking speed of 0.06-0.77 m/s, and 6 minute walk distance of 24-357 m. The effective training schedules ranged from 10 to 130 sessions, with a density of sessions ranging from 2 per week to 5 per week. Earlier training led to superior results both in the subacute (<6 months) and chronic phases (>6 months) after injury, but even individuals with chronic injuries of long duration can improve.

CONCLUSIONS

Frequent, early treatment for individuals with motor incomplete SCI using walking as the active ingredient whether on the treadmill or over ground, generally leads to improved walking over ground. Much work remains for the future, including better quantification of treatment intensity, better outcome measures to quantify a broader range of walking skills, and better ways to retrain individuals with more severe lesions (AIS A and B).

Whole-body vibration and rehabilitation of chronic diseases: a review of the literature

The objectives of the study were to review the current literature and findings on the effects of whole-body vibration (WBV) as a training method on performance and its ability to aid in the rehabilitation of chronic diseases (neurological, musculoskeletal or metabolic conditions). Six electronic databases were searched. The combination of the search terminology used included WBV and several neurological, musculoskeletal and metabolic conditions. Twenty six papers were found to be relevant for this review and were included for critical evaluation with regards to sample characteristics, research intervention and methodology. Most studies were conducted on patients diagnosed with neurological conditions (n = 15) while less were performed on patients suffering from musculoskeletal (n = 7) or metabolic (n = 4) disorders. Comparisons were difficult to draw on because of the different pathologies and the differences in the methodology of each study. Some of the observed methodological flaws included limitations in relation to insufficient randomisation, lack of sample homogeneity (size, age variability) and poor blinding in most studies. No consensus could be reached as to whether WBV is more effective than other interventions or no intervention at all, while the additional effects that WBV may have in relation to other interventions could not be assumed. Nevertheless, chronic WBV training seems to only improve strength in neurological patients while balance and mobility improves only in patients suffering from musculoskeletal or metabolic but not from neurological conditions. Although WBV did not prove to be more effective compared to other training methods, it can be used, in some cases, as a less fatiguing and less time-consuming method to enhance physical capabilities. Future research should focus on the effectiveness of WBV in relation to no treatment at all, and to age. Key pointsChronic WBV training seems to only improve strength in neurological patients while balance and mobility improves only in patients suffering from musculoskeletal or metabolic conditions.WBV did not prove to be more effective than other interventions, while the positive effects of WBV in relation to no intervention at all could not be established.No consensus could be reached as to which vibration type is more effective.WBV training could be used as a safe, less fatiguing and less time-consuming type of exercise for patients with neurologic conditions instead of other more demanding interventions.

Weight bearing through lower limbs in a standing frame with and without arm support and low-magnitude whole-body vibration in men and women with complete motor paraplegia

OBJECTIVE

The aim of the study was to determine the proportion of body weight borne through the lower limbs in persons with complete motor paraplegia using a standing frame, with and without the support of their arms. We also examined the effect of low-magnitude whole-body vibration on loads borne by the lower limbs.

DESIGN

Vertical ground reaction forces (GRFs) were measured in 11 participants (six men and five women) with paraplegia of traumatic origin (injury level T3-T12) standing on a low-magnitude vibrating plate using a standing frame. GRFs were measured in four conditions: (1) no vibration with arms on standing frame tray, (2) no vibration with arms at side, (3) vibration with arms on tray, and (4) vibration with arms at side.

RESULTS

GRF with arms on tray, without vibration, was 0.76 ± 0.07 body weight. With arms at the side, GRF increased to 0.85 ± 0.12 body weight. With vibration, mean GRF did not significantly differ from no-vibration conditions for either arm positions. Oscillation of GRF with vibration was significantly different from no-vibration conditions (P < 0.001) but similar in both arm positions.

CONCLUSIONS

Men and women with paraplegia using a standing frame bear most of their weight through their lower limbs. Supporting their arms on the tray reduces the GRF by approximately 10% body weight. Low-magnitude vibration provided additional oscillation of the load-bearing forces and was proportionally similar regardless of arm position.

Vibration-induced motor responses of infants with and without myelomeningocele

BACKGROUND

The severity of myelomeningocele (MMC) stems both from a loss of neurons due to neural tube defect and a loss of function in viable neurons due to reduced movement experience during the first year after birth. In young infants with MMC, the challenge is to reinforce excitability and voluntary control of all available neurons. Muscle vibration paired with voluntary movement may increase motoneuron excitability and contribute to improvements in neural organization, responsiveness, and control.

OBJECTIVES

This study examined whether infants with or without MMC respond to vibration by altering their step or stance behavior when supported upright on a treadmill.

DESIGN

This was a cross-sectional study.

METHODS

Twenty-four 2- to 10-month-old infants, 12 with typical development (TD) and 12 with MMC (lumbar and sacral lesions), were tested. Infants were supported upright with their feet in contact with a stationary or moving treadmill during 30-second trials. Rhythmic alternating vibrations were applied to the right and left rectus femoris muscles, the lateral gastrocnemius muscle, or the sole of the foot. Two cameras and behavior coding were used to determine step count, step type, and motor response to vibration onset.

RESULTS

Step count decreased and swing duration increased in infants with TD during vibration of the sole of the foot on a moving treadmill (FT-M trials). Across all groups the percentage of single steps increased during vibration of the lateral gastrocnemius muscle on a moving treadmill. Infants with MMC and younger infants with TD responded to onset of vibration with leg straightening during rectus femoris muscle stimulation and by stepping during FT-M trials more often than older infants with TD.

CONCLUSIONS

Vibration seems a viable option for increasing motor responsiveness in infants with MMC. Follow-up studies are needed to identify optimal methods of administering vibration to maximize step and stance behavior in infants.

Vibration Elicits Involuntary, Step-Like Behavior in Individuals With Spinal Cord Injury

Background. Impaired walking is a debilitating consequence of spinal cord injury (SCI). This impairment arises, to some degree, from disruption of supraspinal pathways that activate the spinal locomotor central pattern generator (CPG). Evidence in nondisabled (ND) individuals suggests that vibration activates locomotor CPGs, eliciting involuntary step-like behavior. Objective. To compare vibration-elicited step-like behavior in individuals with chronic SCIs with the responses of ND individuals and to assess the influence of locomotor training on these responses. Methods. Participants included 7 individuals with motor-incomplete SCIs (MISCIs) and 6 with motor-complete SCIs (MCSCIs) who were untrained, 6 individuals with MISCIs who underwent locomotor training, and 8 ND individuals. Kinematic and EMG data were collected while vibration was applied to the quadriceps, hamstrings, or tensor fascia latae (TFL) muscles. Consistency and robustness of vibration-elicited responses was determined from hip and knee angle data. Results. Consistent and reliable step-like behaviors were elicited in individuals with MISCIs and MCSCIs, although responses were not as robust as those in ND individuals. Vibration to the TFL elicited the most robust responses. Consistency and robustness were not influenced by SCI severity or locomotor training but appeared to increase with repeated testing. Conclusion. These results confirm that vibration elicits step-like behaviors in individuals with SCIs, even those with no voluntary motor function in the legs. Further research is warranted to investigate the use of vibration as an approach to activating the spinal CPGs associated with stepping, perhaps as an adjunct to locomotor training for individuals with SCIs.

Gravitational force modulates muscle activity during mechanical oscillation of the tibia in humans

Mechanical oscillation (vibration) is an osteogenic stimulus for bone in animal models and may hold promise as an anti-osteoporosis measure in humans with spinal cord injury (SCI). However, the level of reflex induced muscle contractions associated with various loads (g force) during limb segment oscillation is uncertain. The purpose of this study was to determine whether certain gravitational loads (g forces) at a fixed oscillation frequency (30 Hz) increases muscle reflex activity in individuals with and without SCI. Nine healthy subjects and two individuals with SCI sat with their hip and knee joints at 90° and the foot secured on an oscillation platform. Vertical mechanical oscillations were introduced at 0.3, 0.6, 1.2, 3 and 5 g force for 20 s at 30 Hz. Non-SCI subjects received the oscillation with and without a 5% MVC background contraction. Peak soleus and tibialis anterior (TA) EMG were normalized to M-max. Soleus and TA EMG were <2.5% of M-max in both SCI and non-SCI subjects. The greatest EMG occurred at the highest acceleration (5 g). Low magnitude mechanical oscillation, shown to enhance bone anabolism in animal models, did not elicit high levels of reflex muscle activity in individuals with and without SCI. These findings support the g force modulated background muscle activity during fixed frequency vibration. The magnitude of muscle activity was low and likely does not influence the load during fixed frequency oscillation of the tibia.

Osteoporosis: nonpharmacologic management

Osteoporosis is a chronic disorder of the skeleton causing increased bone fragility and fractures. In the second of our 3-part series, we discuss the beneficial effects of nonpharmacologic agents in the management of osteoporosis. We review the evidence supporting the use of exercise, whole-body vibration, hip protectors, low-intensity pulsed ultrasound, bracing, and vertebral augmentation procedures. The mechanism of action, precautions, and expected outcomes are discussed. Nonpharmacologic management of osteoporosis blends in very well with an overall exercise prescription. The nonpharmacologic interventions discussed are readily available and easy to implement. The use of such techniques demonstrates the important role of the physiatrist in the management of osteoporosis.