Development of Gait Ability Assessment for hemiplegics (GAA) and verification of inter-rater reliability and validity.

Tomida K, Tanino G, Sonoda S, Hirano S, Itoh N, Saitoh E, Kagaya H, Suzuki A, Kawakami K, Miyajima T, Takai M. Development of Gait Ability Assessment for hemiplegics (GAA) and verification of inter-rater reliability and validity. Jpn J Compr Rehabil Sci 2021; 12: 19-26. Objective: To develop the Gait Ability Assessment for hemiplegics (GAA), and to verify its validity and inter-rater reliability. Methods: We developed the GAA, a new method for the assessment of gait ability. Next, we examined the inter-rater reliability of GAA by assessing gait ability of post-stroke patients by two physical therapists. Then, we verified the validity of GAA by comparing with the existing assessments methods comprising Functional Ambulation Categories (FAC), Functional Independence Measure (FIM)-walk, maximum walking speed, motor subscore of the FIM (FIM-M), and total score of affected-side motor function of the Stroke Impairment Assessment Set (SIAS-L/E). Results: Regarding the inter-rater reliability of GAA, κ coefficient was 0.76 and weighted κ coefficient was 0.96. The correlation coefficients between GAA scores and existing assessment methods were: 0.95 for FAC scores, 0.95 for FIM-walk scores, 0.82 for maximum walking speed, 0.89 for FIM-M, and 0.61 for SIAS-L/E, all of which showed a significant correlation (p<0.01). Conclusion: GAA has high inter-rater reliability as well as high validity as a gait ability assessment method, suggesting that it can be applied to research and clinical settings.

Motion analysis of operating a balance exercise assist robot system during forward and backward movements.

[Purpose] Stand-and-ride personal mobility devices controlled by movements of the user's center of gravity are used for balance training. We aimed to describe the physical activity required to operate this type of mobility device. [Participants and Methods] Eleven healthy males performed the following tasks: 1) moving their center of gravity forward or backward while standing on the floor (control task) and, 2) moving the mobility device forward or backward by moving their center of gravity (experimental task). [Results] We observed that the displacement of the center of gravity and the center of pressure, as well as angular displacements of the hips and knee joints, and maximum muscle activities of the biceps femoris, the medial head of the gastrocnemius and peroneus longus muscles were lesser during the experimental than during the control task. The distance moved by the device was significantly greater than the displacement of the user's center of gravity during the experimental task. [Conclusion] We observed that moving the device forward or backward required lesser physical activity than that required to shift the user's center of gravity forward or backward while standing on the floor. Additionally, we observed that even a small displacement of the user's center of gravity produced a large displacement of the device. We concluded that during balance training, the greater and more easily perceived movement of the mobility device would provide helpful feedback to the user.

Kinematic, kinetic, and electromyographic characteristics during quiet standing on a balance exercise assist robot.

[Purpose] The balance exercise assist robot is a training device based on a personal transport assistance robot ridden in the standing position. The personal transport assistance robot uses an inverted pendulum control system and moves in response to movements of the user's center of gravity. The purpose of this study was to describe the characteristics of postural control during the action of stopping the personal transport assistance robot. [Participants and Methods] Eleven healthy male participants were required to maintain a standing position for 30 s; each task was performed 10 times. The measurement conditions were as follows: (1) on the floor; (2) on the robot, touching the handlebars; and (3) on the robot, not touching the handlebars. [Results] During the robotic tasks, the total locus lengths of the center of gravity and total joint momentums of the hip, knee, and ankle joints were larger, and the amount of displacement of the center of pressure was smaller than that during the floor task. Posture control on the robot was performed actively by mechanical interaction of the ankle, knee, and hip joints within a small base of support. [Conclusion] The balance exercise assist robot can be useful for postural control exercises because maintaining a standing position on the personal transport assistance robot required active postural control.

Gait training using a stationary, one-leg gait exercise assist robot for chronic stroke hemiplegia: a case report.

[Purpose] The Gait Exercise Assist Robot (GEAR) is a stationary, one-leg robot for gait training. The purpose of this case study was to evaluate the efficacy of rehabilitation using GEAR training for chronic stroke hemiplegia. [Participant and Methods] The participant was a 66-year-old male stroke survivor with left hemiparesis due to a right putaminal hemorrhage. He could walk slowly under supervision, although his gait had a constant forward trunk lean, with flexed knee, and a lack of hip extension movement on the affected side. Gait training using GEAR and physical therapy were performed for 14 days. Under both training conditions, the physical therapist made the participant conscious of extension movement of the hip joint in the affected-side stance phase. The robotic assistance was adjusted to maximize voluntary movement while observing gait. Physical function and gait ability parameters were evaluated before and after training. [Results] After training, extension motion of the hip joint increased in the affected-side stance phase, and body weight was transferred smoothly onto the affected-side limb, leading to an improvement in gait speed. [Conclusion] Gait training using GEAR and physical therapy may improve gait pattern and speed in patients with chronic stroke hemiplegia.

Clinical-oriented Three-dimensional Gait Analysis Method for Evaluating Gait Disorder.

Three-dimensional gait analysis (3DGA) is shown to be a useful clinical tool for the evaluation of gait abnormality due to movement disorders. However, the use of 3DGA in actual clinics remains uncommon. Possible reasons could include the time-consuming measurement process and difficulties in understanding measurement results, which are often presented using a large number of graphs. Here we present a clinician-friendly 3DGA method developed to facilitate the clinical use of 3DGA. This method consists of simplified preparation and measurement processes that can be performed in a short time period in clinical settings and intuitive results presentation to facilitate clinicians' understanding of results. The quick, simplified measurement procedure is achieved by the use of minimum markers and measurement of patients on a treadmill. To facilitate clinician understanding, results are presented in figures based on the clinicians' perspective. A Lissajous overview picture (LOP), which shows the trajectories of all markers from a holistic viewpoint, is used to facilitate intuitive understanding of gait patterns. Abnormal gait pattern indices, which are based on clinicians' perspectives in gait evaluation and standardized using the data of healthy subjects, are used to evaluate the extent of typical abnormal gait patterns in stroke patients. A graph depicting the analysis of the toe clearance strategy, which depicts how patients rely on normal and compensatory strategies to achieve toe clearance, is also presented. These methods could facilitate implementation of 3DGA in clinical settings and further encourage development of measurement strategies from the clinician's point of view.

The features of Gait Exercise Assist Robot: Precise assist control and enriched feedback.

BACKGROUND: In a patient with severe hemiplegia, the risk of the knee giving way is high during the early stage of gait exercise with an ankle-foot orthosis. However, use of a knee-ankle-foot orthosis has many problems such as large amount of assistance and compensatory motions. To resolve these problems, we have engaged in the development of the Gait Exercise Assist Robot (GEAR). OBJECTIVE: To evaluate the improvement efficiency of walk with GEAR in a stroke patient. METHODS: The subject was a 70-year-old man presented with left thalamus hemorrhage and right hemiplegia. The patient underwent exercise with the GEAR 5 days a week, for 40 minutes per day. We evaluated the Functional Independence Measure score for walk (FIM-walk score) every week. The control group consisted of 15 patients aged 20-75 years with hemiplegia after primary stroke, who had equivalent walking ability with the subject at start. As the primary outcome, we defined improvement efficiency of FIM-walk, which was gain of FIM-walk divided the number of required weeks. RESULTS: Improvement efficiency of FIM-walk of the subject was 1.5, while that of control group was 0.48±3.2 (mean±SD). CONCLUSIONS: GEAR is potentially useful for gait exercise in hemiplegic patients.

Changes in postural strategy during exercise against perturbation using the balance exercise assist robot: a pilot study.

[Purpose] To clarify the changes in postural strategy by evaluating leg joint motion and muscle activity before and after continuous exercise against perturbation using the Balance Exercise Assist Robot (BEAR). [Subjects and Methods] Nine healthy subjects (male 7, female 2; mean age 23 ± 1 years) performed a postural perturbation coping exercise only. In the task, the robot leaned and moved automatically. Participants were instructed to maintain their default upright position and they performed the exercise five times in a row (1 minute/trial). Changes in total movement distance, range of motion of each joint (hip, knee, ankle), and mean activity of each muscle for the first and fifth trials were compared. [Results] The total movement distance of BEAR and range of motion in the hip decreased significantly from the first trial to the last trial. No change in muscle activity was observed in the rectus femoris, biceps femoris, tibialis anterior or gastrocnemius. [Conclusion] The results for exercise against perturbation using BEAR in this study suggest that BEAR may be a promising method to improve the ankle strategy for maintaining a standing posture.

Efficacy of Botulinum Toxin A Treatment for Pes Varus during Gait.

BACKGROUND: The efficacy of botulinum toxin A (BoNTA) injection on spasticity is usually measured using Modified Ashworth Scale (MAS), but this only evaluates muscle tone at rest and has poor reliability. There are no reports that quantitatively evaluate pes varus during walking after botulinum treatment. The purpose of this study was to evaluate the efficacy of BoNTA injection on pes varus during gait using 3-dimensional motion analysis. METHODS: Twenty-four hemiplegic patients with spastic pes varus deformity during gait received BoNTA injection into lower limb muscles. MAS score, comfortable overground gait velocity, and pes varus angle during treadmill walking were evaluated before, 2, 6, and 12 weeks after the injection. Five healthy subjects were also recruited to develop the pes varus/valgus angle as a normal reference. RESULTS: The median MAS scores were significantly lower at 2 and 6 weeks after the injection. The maximum pes varus angle during the swing phase was significantly lower at 2, 6, and 12 weeks after the injection. It was significantly lower at 6 weeks after the injection during stance phase. The comfortable overground gait velocity was also improved after the injection. However, 2 patients experienced pain during gait and their pes varus angle increased during the follow-up period. CONCLUSIONS: BoNTA injection improved pes varus angle during gait. Evaluating motion in addition to spasticity at rest is recommended because improvements in limb function do not always parallel improvements in spasticity at rest.

Stimulus point distribution in deep or superficial peroneal nerve for treatment of ankle spasticity.

OBJECTIVES: To develop effective electrical stimulation treatment to reduce spasticity, we examined the optimal stimulus point of the common peroneal nerve. MATERIALS AND METHODS: The locations of selective stimulus points for the deep peroneal nerve or superficial peroneal nerve fiber were examined in 25 healthy subjects in both legs (50 legs) using the ratio of the tibialis anterior (TA) to the peroneus longus (PL) M-wave amplitude (TA/PL ratio). In addition, we measured reciprocal Ia inhibition in ten healthy subjects. The amount of inhibition was determined from short-latency suppression of the soleus (Sol) H-reflex by conditioning stimuli to the deep or superficial peroneal nerve. The paired t-test was used for statistical analysis. RESULTS: The mean TA/PL ratio during deep peroneal nerve stimulation was significantly different from superficial peroneal nerve stimulation (p < 0.001). The mean stimulus point for the deep peroneal nerve was located 7 ± 5 mm distal and 3 ± 6 mm anterior from the distal edges of the head of fibula and was markedly different from the stimulus point for the superficial peroneal nerve (20 ± 7 mm distal and 12 ± 8 mm posterior). During deep peroneal nerve stimulation, the mean conditioned H-reflex was depressed to 83.8 ± 10.7% of the unconditioned value of the H-reflex. In contrast, during superficial peroneal nerve stimulation, the mean conditioned H-reflex increased to 105.3 ± 5.2%. These values were significantly different (p < 0.001). CONCLUSIONS: In the present study, we revealed a stimulus area of the deep peroneal nerve. Also, we observed the inhibitory effects of stimulation upon the deep peroneal nerve at individual stimulus point. Our results appear to indicate that localized stimulation of the deep peroneal nerve is more useful for the reduction of ankle spasticity.

Preliminary trial of postural strategy training using a personal transport assistance robot for patients with central nervous system disorder.

OBJECTIVE: To examine the efficacy of postural strategy training using a personal transport assistance robot (PTAR) for patients with central nervous system disorders. DESIGN: Single-group intervention trial. SETTING: Rehabilitation center at a university hospital. PARTICIPANTS: Outpatients (N=8; 5 men, 3 women; mean age, 50±13y) with a gait disturbance (mean time after onset, 34±29mo) as a result of central nervous system disorders were selected from a volunteer sample. INTERVENTIONS: Two methods of balance exercise using a PTAR were devised: exercise against perturbation and exercise moving the center of gravity. The exercises were performed twice a week for 4 weeks. MAIN OUTCOME MEASURES: Preferred and tandem gait speeds, Functional Reach Test, functional base of support, center of pressure (COP), muscle strength of lower extremities, and grip strength were assessed before and after the completion of the exercise program. After the exercise program, enjoyment of exercise was investigated via a visual analog scale questionnaire. RESULTS: After the program, statistically significant improvements were noted for tandem gait speeds (P=.009), Functional Reach Test (P=.003), functional base of support (P=.014), and lower extremity muscle strength (P<.001-.042). On the other hand, preferred gait speeds (P=.151), COP (P=.446-.714), and grip power (P=.584) did not change. Finally, subjects rated that this exercise was more enjoyable than traditional balance exercises. CONCLUSIONS: Dynamic balance and lower extremity muscle strength were significantly improved in response to postural strategy training with the PTAR. These results suggest that postural strategy training with the PTAR may contribute to fall prevention of patients with a balance disorder.