Does galvanic vestibular stimulation decrease spasticity in clinically complete spinal cord injury?

The aim of this study was to determine changes in clinical and biomechanical measures of spasticity after administering galvanic vestibular stimulation in patients with a complete spinal cord injury (SCI). The spasticity in the lower limbs was assessed using the Modified Ashworth Scale and the pendulum test in seven SCI patients (grade A on the ASIA Impairment Scale) before (0), immediately after (0), and at 5 and 30 min after the real versus sham galvanic vestibular stimulation (15 s each, anode over the right mastoid). Overall, the changes in spasticity were not significantly different between the real and sham galvanic vestibular stimulation. However, the Modified Ashworth Scale and the pendulum test indicated a reduction in spasticity in two out of seven patients. The results suggest that galvanic vestibular stimulation may modify spasticity in some patients with complete SCI, presumably through the residual vestibulospinal influences. Future studies should determine clinical and neurophysiological profiles of responders versus nonresponders and optimize parameters of galvanic vestibular stimulation.

Gait training of poststroke patients assisted by the Walkaround (body postural support).

Improvement in gait abilities is one of the important goals of stroke rehabilitation. The Walkaround is a new postural assistance device for gait training, which allows an early start for gait training. This device provides body postural support (BPS) and trunk orientation by means of a lumbar belt that is connected to a powered rolling walker. We conducted a randomized, single-blinded, 4-week clinical trial of 22 subacute stroke patients with a follow-up period of 6 months. Patients were divided into two identically sized groups: the treatment group (BPS), which was assisted by the Walkaround, and the control (CON) group, which was assisted by conventional means (cane, therapist) during gait training. The objective of the study was to assess whether the Walkaround is more effective than conventional assistance during gait training. The outcome measures were as follows: Barthel index, Fugl-Meyer score for the lower extremities, Berg balance test, and gait speed. Changes in the outcome measures were significant for the Berg balance score after 6 months in both groups and in gait speed among the BPS group at the end of therapy and after 6 months (P<0.05) compared with the same outcome measures at the beginning of the trial. Significant differences were found in gait speed and Berg balance test scores after 4 weeks and in gait speed after 6 months (P<0.05) between the BPS and the CON groups. The results suggest that added postural support by the Walkaround led to limited yet significant changes in gait speed and balance control.

Distributed low-frequency functional electrical stimulation delays muscle fatigue compared to conventional stimulation.

We present a low-frequency stimulation method via multi-pad electrodes for delaying muscle fatigue. We compared two protocols for muscle activation of the quadriceps in paraplegics. One protocol involved a large cathode at 30 HZ (HPR, high pulse-rate), and the other involved four smaller cathodes at 16 HZ (LPR, low pulse-rate). The treatment included 30-min daily sessions for 20 days. One leg was treated with the HPR protocol and the other with the LPR protocol. Knee-joint torque was measured before and after therapy to assess the time interval before the knee-joint torque decreased to 70% of the initial value. The HPR therapy provided greater increases in muscle endurance and force in prolonged training. Yet the LPR stimulation produced less muscle fatigue compared to the HPR stimulation. The results suggest that HPR is the favored protocol for training, and LPR is better suited for prolonged stimulation.

Lumbar stimulation belt for therapy of low-back pain.

We developed the STIMBELT, an electrical stimulation system that comprises a lumbar belt with up to eight pairs of embedded electrodes and an eight-channel electronic stimulator. The STIMBELT is an assistive system for the treatment of low-back pain (LBP). We describe here technical details of the system and summarize the results of its application in individuals with subacute and chronic LBP. The direct goals of the treatment were to relieve pain, reduce muscle spasms, increase strength and range of motion, and educate individuals with LBP in reducing the chances of its reoccurrence. The outcome measures include: a Visual Analogue Scale (VAS), the Oswestry LBP Disability Questionnaire, the Short Form (SF)-12 health survey, and the Manual Muscle Test. The results indicate significant benefits for individuals who use the STIMBELT in addition to the conventional therapy as opposed to only the conventional therapy.

The drawing test: assessment of coordination abilities and correlation with clinical measurement of spasticity.

OBJECTIVE: To assess the correlation between kinematic measures of movement (Drawing Test) and a clinical measure of spasticity (Ashworth Scale). DESIGN: Correlation study of Drawing Test and the Ashworth Scale scores. SETTING: Inpatient rehabilitation center. PARTICIPANTS: Forty-five poststroke hemiplegic subjects with various levels of spasticity (up to Ashworth Scale score of 3) and 8 able-bodied subjects with no sensorimotor deficits in their upper extremities. INTERVENTIONS: Subjects made self-paced, radial point-to-point movements between the left, and the right corners of a square (200 x 200 mm) on the surface of a drawing tablet. Hand coordinates were recorded from the mouse, which was attached to the hand. MAIN OUTCOME MEASURES: Correlation between (1) Drawing Test scores (time to perform the movement, radial [ y ] and tangential [ x ] distances between the end point of the movement and the target endpoint, standard error of the mean calculated as distances between the recorded path and its radial linear fit), and (2) Ashworth Scale scores. RESULTS: Drawing Test scores correlated highly with Ashworth Scale scores in 49 of 53 subjects, based on the multiple linear regression analysis. CONCLUSIONS: The Drawing Test, a quantitative metric of movement ability, correlated highly to the Ashworth Scale, a clinical measure of spasticity.

Therapy of paretic arm in hemiplegic subjects augmented with a neural prosthesis: a cross-over study.

There are indications that both intensive exercise and electrical stimulation have a beneficial effect on arm function in post-stroke hemiplegic patients. We recommend the use of Functional Electrical Therapy (FET), which combines electrical stimulation of the paretic arm and intensive voluntary movement of the arm to exercise daily functions. FET was applied 30 min daily for 3 weeks. Forty-one acute hemiplegics volunteered in the 18-months single blinded cross-over study (CoS). Nineteen patients (Group A) participated in FET during their acute hemiplegia, and 22 patients (Group B) participated in FET during their chronic phase of hemiplegia. Group B patients were controls during FET in acute hemiplegia, and Group A patients were controls during the FET in chronic hemiplegia. Thirty-two patients completed the study. The outcomes of the Upper Extremity Function Test (UEFT) were used to assess the ability of patients to functionally use objects, as were the Drawing Test (DT) (used to assess the coordination of the arm), the Modified Ashworth Scale, the range of movement, and the questionnaire estimating the patients' satisfaction with the usage of the paretic arm. Patients who participated in the FET during the acute phase of hemiplegia (Group A) reached functionality of the paretic arm, on average, in less than 6 weeks, and maintained this near-normal use of the arm and hand throughout the follow-up. The gains in all outcome scores were significantly larger in Group A after FET and at all follow-ups compared with the scores before the treatment. The gains in patients who participated in the FET in the chronic phase of hemiplegia (Group B) were measurable, yet not significant. The speed of recovery was larger during the period of the FET compared with the follow-up period. The gains in Group A were significantly larger compared with the gains in Group B. The FET greatly promotes the recovery of the paretic arm if applied during the acute phase of post-stroke hemiplegia.

Functional Electrical Therapy (FET): Clinical Trial in Chronic Hemiplegic Subjects.

Results from a clinical evaluation of Functional Electrical Therapy (FET) in chronic hemiplegic subjects are presented. FET is an intensive exercise that integrates voluntary maximized manipulation and augmented grasping by electrical stimulation of forearm and hand muscles. A total of 16 chronic hemiplegic subjects participated in a six-month long study. The subjects were divided into lower and higher functioning groups based on their capacity to voluntarily extend the wrist and fingers against gravity. Functional Electrical Therapy comprised 30-min electrically assisted daily exercise of the paretic arm for three consecutive weeks. The outcome measures included Upper Extremity Function Test (UEFT), the Drawing Test (DT), and Modified Ashworth Scale (MAS) of spasticity. The UEFT objectively measured the abilities to grasp and manipulate objects during typical daily activities. The DT measured the ability to coordinate shoulder and elbow joints. The MAS assessed the tone of the paretic arm muscles. The control group was formed from hemiplegic subjects that received FET in their acute phase of hemiplegia and were evaluated in our earlier study. The results showed that FET slightly increases the ability to reach and grasp, and decreases absolute mean spasticity of chronic hemiplegic subjects. The gains in UEFT and DT were measurable, yet not statistically significant. The trends of UEFT and DT scores during the therapy (three weeks) were steeper when compared with the trend during follow-up (23 weeks). The changes of the trends during the study suggest that prolonged treatment could lead to bigger gains. We found standard deviations were increased towards the end of follow-up suggesting individual differences in response to either the treatment or the disablement process.

Automatic vs hand-controlled walking of paraplegics.

A rule-based control and its application in functional electrical stimulation (FES) assisted walking of subjects with paraplegia are described in this paper. The design of rules for control comprises the following two steps: (1) determination of muscle activation patterns by using a fully customized spatial (3D) model of paraplegic walking, and (2) learning of rules, that is, correlation between the muscle activation patterns and kinematics of walking by means of an artificial neural network. The adopted FES system activated eight muscle groups with surface electrodes. The only joints allowing movement in the coronal plane were the hips, and externally controlled joints in sagittal plane were ankles, knees and hips. The simulation minimized the tracking error of the joint angles and the total activation of all eight muscles being stimulated. A radial-basis function artificial neural network was applied for learning of rules. Three automatically controlled modes (slow, near-normal, and near-ballistic) and hand-controlled walking were evaluated in six subjects with a complete spinal cord lesion (T8-T10). The performance of walking was assessed by the following: (1) energy consumption based on oxygen uptake, (2) physiological cost index, (3) maximum speed of walking, and (4) a questionnaire. The results showed that all modes of walking are achievable and that automatic control leads to more efficient and faster walking. The speed of walking achieved by automatic control was almost three times bigger compared with the speed of hand-controlled walking. The energy cost and rate decreased significantly when automatic control was applied; yet, they were still much bigger than the values measured in able-bodied subjects. The objective outcome measures suggest that the near-ballistic walking was the most effective, yet a questionnaire shows that most subjects preferred slow walking. The most likely reason for the preference of lower efficiency walking over the faster end energy efficient near-ballistic walking was that paraplegic patients had difficulties in synchronizing the voluntary movement of the trunk and arms to the artificially controlled movements of legs.

Clinical evaluation of Functional Electrical Therapy in acute hemiplegic subjects.

This paper describes a clinical randomized single-blinded study of the effects of Functional Electrical Therapy (FET) on the paretic arms of subjects with acute hemiplegia caused by strokes. FET is an exercise program that comprises voluntary arm movements and opening, closing, holding, and releasing of objects that are assisted by a neural prosthesis (electrical stimulation). FET consisted of a 30 min everyday exercise for 3 consecutive weeks in addition to conventional therapy. Twenty-eight acute hemiplegic subjects participated in a 6 mo study. The subjects were divided into lower functioning groups (LFGs) and higher functioning groups (HFGs) based on their capacity to voluntarily extend the wrist and fingers against the gravity, and were randomly assigned to controls or FET groups. The outcomes included the Upper Extremity Function Test, the coordination of elbow and shoulder movements, spasticity of key muscles of the paretic arm, and Reduced Upper Extremity Motor Activity Log. FET and control groups showed a recovery trend in all outcome measures. The gains in FET groups were much larger compared with the gains in control groups. The speed of recovery in FET groups was substantially faster compared with the recovery rate in control groups during the first 3 weeks (treatment). The LFG subjects showed less improvement than the HFG in both the FET and control groups.

Restitution of reaching and grasping promoted by functional electrical therapy.

Functional electrical therapy (FET) is a new term describing a combination of functional electrical stimulation that generates life-like movement and intensive exercise in humans with central nervous system lesions. We hypothesized that FET can promote a significant recovery of functioning if applied in subacute stroke subjects. The study included 16 stroke subjects divided into a low functioning group (LFG) and a high functioning group (HFG) based on their ability to control wrist and fingers and randomly associated into FET and controls. The FET consisted of 30 min daily sessions during 3 weeks. The exercise comprised functional use of daily necessary activities (e.g., writing, using a telephone receiver, and drinking from a can). The outcome presented in this article is the upper-extremity function test performed before and after the therapy. The change in performance of the HFG group was significant. The number of successful repetitive movements in 2 min was doubled and 1.6 times increased for controls, and the time to perform the movement was decreased by 71% percent and by 36% in controls. In the LFG FET group, the difference in performance was the following. First, the number of tasks was increased from 0 to 6 (total of 11 tasks). Second, the averaged number of successful repetitive movements was increased from 0 to 3. The functional improvement in the FET LFG is probably not sufficient to make the more affected arm/hand effective for daily necessities; thus, the FET effects could deteriorate over a longer time. The subjects from the control LFG made only a marginal improvement. The follow-up for each subject will continue for 12 months after the beginning of the treatment.