Energy consumption and cost during walking with different modalities of assistance after stroke: a systematic review and meta-analysis

Immediate Effect of Ankle Exoskeleton on Spatiotemporal Parameters and Center of Pressure Trajectory After Stroke

Gait impairments is a common condition in post-stroke subjects. We recently presented a wearable ankle exoskeleton called G-Exos, which showed that the device assisted in the ankle's dorsiflexion and inversion/reversion movements. The aim of the current pilot study was to explore spatiotemporal gait parameters and center of pressure trajectories associated with the use of the G-Exos in stroke participants. Three post-stroke subjects (52-63 years, 2 female/1 male) walked 160-meter using the G-Exos on the affected limb, on a protocol divided into 4 blocks of 40-meters: (I) without the exoskeleton, (II) with systems hybrid system, (III) active only and (IV) passive only. The results showed that the use of the exoskeleton improved swing and stance phases on both limbs, reduced stride width on the paretic limb, increased stance COP distances, and made single support COP distances more similar between the paretic and non-paretic limb. This suggests that all G-Exos systems contributed to improving body weight bearing on the paretic limb and symmetry in the gait cycle.

Convergent Validity of the Timed Walking Tests with Functional Ambulatory Category in Subacute Stroke

Determining the walking ability of post-stroke patients is crucial for the design of rehabilitation programs and the correct functional information to give to patients and their caregivers at their return home after a neurorehabilitation program. We aimed to assess the convergent validity of three different walking tests: the Functional Ambulation Category (FAC) test, the 10-m walking test (10MeWT) and the 6-minute walking test (6MWT). Eighty walking participants with stroke (34 F, age 64.54 ± 13.02 years) were classified according to the FAC score. Gait speed evaluation was performed with 10MeWT and 6MWT. The cut-off values for FAC and walking tests were calculated using a receiver-operating characteristic (ROC) curve. Area under the curve (AUC) and Youden's index were used to find the cut-off value. Statistical differences were found in all FAC subgroups with respect to walking speed on short and long distances, and in the Rivermead Mobility Index and Barthel Index. Mid-level precision (AUC > 0.7; p < 0.05) was detected in the walking speed with respect to FAC score (III vs. IV and IV vs. V). The confusion matrix and the accuracy analysis showed that the most sensitive test was the 10MeWT, with cut-off values of 0.59 m/s and 1.02 m/s. Walking speed cut-offs of 0.59 and 1.02 m/s were assessed with the 10MeWT and can be used in FAC classification in patients with subacute stroke between the subgroups able to walk with supervision and independently on uniform and non-uniform surfaces. Moreover, the overlapping walking speed registered with the two tests, the 10MeWT showed a better accuracy to drive FAC classification.

Feasibility of challenging treadmill speed-dependent gait and perturbation-induced balance training in chronic stroke patients with low ambulation ability: a randomized controlled trial

Background

Treadmill training shows advantages in the specificity, amount, and intensity of gait and balance practice for the rehabilitation of stroke patients.

Objective

To investigate the feasibility and effectiveness of challenging treadmill speed-dependent gait and perturbation-induced balance training in chronic stroke patients with low ambulation ability.

Methods

For this randomized controlled trial (Chinese Clinical Trials.gov registration number ChiCTR-IOR-16009536) with blinded testers, we recruited 33 ambulatory stroke participants with restricted community ambulation capacity and randomly assigned them into two groups: the experimental group with 2 week treadmill speed-dependent gait training combined with 2 week treadmill perturbation-induced balance training (EXP) or the control group with traditional gait and balance training (CON). Various variables were recorded during EXP training, including the rating of perceived exertion, heart rate, causes of pauses, treadmill speed, and perturbation intensity. Outcome measures were examined before training and at 2 and 4 weeks after training. They included gait velocity during five-meter walk test at comfortable and fast speed and reactive balance ability in the compensatory stepping test as primary outcome measures, as well as dynamic balance ability (timed up-and-go test and 5 times sit-to-stand test) and balance confidence as secondary outcome measures.

Results

All participants completed the study. The treadmill speed and perturbation intensity significantly increased across training sessions in the EXP group, and no adverse effects occurred. The normal and fast gait velocities showed significant time and group interaction effects. They significantly increased after 2 and 4 weeks of training in the EXP group (p < 0.05) but not in the CON group (p > 0.05). Likewise, dynamic balance ability measured using the timed up-and-go test at a fast speed significantly improved after 2 and 4 weeks of training in the EXP group (p < 0.05) but not in the CON group (p > 0.05), although without a significant time and group interaction effect. Surprisingly, the reactive balance ability did not show improvement after treatment in the EXP group (p > 0.05).

Conclusion

Challenging treadmill speed-dependent gait and treadmill perturbation-induced balance training is feasible and effective to improve ambulation function in chronic stroke patients with low ambulation ability.

Effects of various hyperopia intervention levels on male college students' gait kinematics

Background: Hyperopia is a common blurred vision phenomenon that affects postural control in gait; however, current research has focused on the alteration and correction of hyperopia's physiological characteristics, ignoring the effect of hyperopia on gait kinematic characteristics. The effect of hyperopia on the basic form of movement walking is a worthy concern. Objective: To investigate the gait kinematic characteristics of male college students with varying degrees of visual acuity (normal vision, hyperopia 150°, and hyperopia 450°), as well as to provide a theoretical foundation for the effect of visual acuity on gait and fall risk reduction. Methods: Twenty-two male college students with normal visual acuity were chosen. Their vision was tested using a standard visual acuity logarithm table at normal and with 150° and 450° concave lenses. Gait kinematic data were collected under normal vision and hyperopic conditions using the PN3 Pro advanced inertial motion capture system and Axis Studio application program. Results and conclusion: 1. The change of center of gravity in Pre-double support was smaller than normal vision; Late-single support and Late-swing was larger than normal vision; 2. The percentage of the double-leg support decreased; the percentage of the single-leg support and the Late-swing increased; 3. For the joints' range of motion, Trunk flexion and extension range of motion in Pre-single support, Late-double support and Pre-swing smaller than normal visual acuity, and Late-swing larger than normal; hip internal abduction and adduction and internal and external rotation are larger than normal vision in Late-single support; knee and ankle in abduction and adduction direction are larger than normal vision in the swing stage; hip flexion and extension, internal external rotation are larger than normal vision in the swing stage. Hyperopic interventions have an impact on the kinematic characteristics of gait in male college students, mainly in terms of altered balance, increased instability, increased difficulty in maintaining trunk stability, and increased risk of injury.

The effect of robot-assisted walking in different modalities on cardiorespiratory responses and energy consumption in patients with subacute stroke

OBJECTIVES

The aim of our study was to evaluate the effect of robot-assisted walking in different modalities on cardiorespiratory responses and energy consumption in subacute stroke patients.

METHODS

Our study consisted of 16 individuals between the ages of 18-65 years. Individuals diagnosed with hemiplegia after unilateral ischemic or haemorrhagic stroke constitute the stroke group. Eight subacute stroke individuals were included in the experimental group, and eight healthy individuals were included in the control group. Each participant tested on the Lokomat in three consecutive days in random sequence, with three tests: the first test: 100% guiding strength (GF)and 100% body weight support (BWS); the second test 80% GF, 50% BWS; the third test 60% GF, 30% BWS was achieved. Gas analyzer (Cosmed, Quark CPET, Italy) measurements were made with the help of a mask to evaluate the cardiorespiratory responses of the participants during all tests.

RESULTS

In the comparison of the three test results of the two groups separately, the stroke group's oxygen consumption (VO2), carbon dioxide production (VCO2), tidal volume (VT), pulse reserve (HRR), calories burned per hour (EEh), Borg dyspnea values, control group's VO2, VCO2, VE, HR, HRR, and EEh, Borg values were statistically significantly different (p < 0.005). It was seen that the third test results were significantly greater than the first and second test results (p < 0.005).

DISCUSSION

By decreasing GF and BWS values during robot-assisted walking, adequate cardio-metabolic and energy response in both subacute stroke patients and healthy individuals could be achieved. These results show us that it is important to consider the cardiorespiratory function of the patient when choosing training protocols.

Balance Rehabilitation through Robot-Assisted Gait Training in Post-Stroke Patients: A Systematic Review and Meta-Analysis

BACKGROUND

Balance impairment is a common disability in post-stroke survivors, leading to reduced mobility and increased fall risk. Robotic gait training (RAGT) is largely used, along with traditional training. There is, however, no strong evidence about RAGT superiority, especially on balance. This study aims to determine RAGT efficacy on balance of post-stroke survivors.

METHODS

PubMed, Cochrane Library, and PeDRO databases were investigated. Randomized clinical trials evaluating RAGT efficacy on post-stroke survivor balance with Berg Balance Scale (BBS) or Timed Up and Go test (TUG) were searched. Meta-regression analyses were performed, considering weekly sessions, single-session duration, and robotic device used.

RESULTS

A total of 18 trials have been included. BBS pre-post treatment mean difference is higher in RAGT-treated patients, with a pMD of 2.17 (95% CI 0.79; 3.55). TUG pre-post mean difference is in favor of RAGT, but not statistically, with a pMD of -0.62 (95%CI - 3.66; 2.43). Meta-regression analyses showed no relevant association, except for TUG and treatment duration (β = -1.019, 95% CI - 1.827; -0.210, p-value = 0.0135).

CONCLUSIONS

RAGT efficacy is equal to traditional therapy, while the combination of the two seems to lead to better outcomes than each individually performed. Robot-assisted balance training should be the focus of experimentation in the following years, given the great results in the first available trials. Given the massive heterogeneity of included patients, trials with more strict inclusion criteria (especially time from stroke) must be performed to finally define if and when RAGT is superior to traditional therapy.

Thigh and Shank, Kinetic and Potential Energies during Gait Swing Phase in Healthy Adults and Stroke Survivors

Background/Problem. Given the treatment-resistant gait deficits after stroke and known elevated energy cost of gait after stroke, it is important to study the patterns of mechanical energies of the lower limb segments. There is a dearth of information regarding mechanical energies specifically for the thigh and shank across the gait cycle. Therefore, the purpose of the current work was to characterize the following: (1) relative patterns of oscillation kinetic energy (KE) and potential energy (PE) within lower limb segments and across lower limb segments in healthy adults during the swing phase at chosen and slow gait speeds; (2) KE and PE swing phase patterns and values for stroke survivors versus healthy adults walking at slow speed; and (3) KE and PE patterns during the swing phase for two different compensatory gait strategies after stroke,. Methods. This was a gait characterization study, a two-group, parallel-cohort study of fourteen stroke survivors with gait deficits, walking at <0.4 m/s and eight adults with no gait deficits. For testing, the eight healthy adults walked at their chosen speed, and then at the imposed slow speed of <0.04 m/s. We used a standard motion capture system and calculation methods to acquire, calculate, and characterize oscillation patterns of KE and PE of the limb segments (thigh and shank) across the gait cycle. Results. In healthy adults, we identified key energy conservation mechanisms inherent in the interactions of KE and PE, both within the thigh and shank segments and across those limb segments, partially explaining the low cost of energy of the normal adult chosen speed gait pattern, and the underlying mechanism affording the known minimal set of activated muscles during walking, especially during the early swing phase. In contrast, KE was effectively absent for both healthy adults at imposed slow walking speed and stroke survivors at their very slow chosen speed, eliminating the normal conservation of energy between KE and PE within the thigh and across the thigh and shank. Moreover, and in comparison to healthy adult slow speed, stroke survivors exhibited greater abnormalities in mechanical energies patterns, reflected in either a compensatory stepping strategy (over-flexing the hip) or circumducting strategy (stiff-legged gait, with knee extended throughout the swing phase). Conclusions and contribution to the field. Taken together, these findings support targeted training to restore normal balance control and normal activation and de-activation coordination of hip, knee, and ankle muscles, respectively (agonist/antagonist at each joint), so as to eliminate the known post-stroke abnormal co-contractions; this motor training is critical in order to release the limb to swing normally in response to mechanical energies and afford the use of conservation of KE and PE energies within the thigh and across thigh and shank.

Photobiomodulation Therapy Combined with Static Magnetic Field (PBMT–SMF) on Spatiotemporal and Kinematics Gait Parameters in Post-Stroke: A Pilot Study

Background: Gait deficit is a major complaint in patients after stroke, restricting certain activities of daily living. Photobiomodulation therapy combined with a static magnetic field (PBMT-SMF) has been studied for several diseases, and the two therapies are beneficia. However, their combination has not yet been evaluated in stroke. Therefore, for PBMT–SMF to be used more often and become an adjunctive tool in the rehabilitation of stroke survivors at physical therapy rehabilitation centers and clinics, some important aspects need to be clarified. Purpose: This study aimed to test different doses of PBMT–SMF, to identify the ideal dose to cause immediate effects on the spatiotemporal and kinematic variables of gait in post-stroke patients. Methods: A randomized, triple-blinded, placebo-controlled crossover pilot study was performed. A total of 10 individuals with hemiparesis within 6 months to 5 years since the occurrence of stroke, aged 45–60 years, were included in the study. Participants were randomly assigned and treated with a single PBMT–SMF dose (sham, 10 J, 30 J, or 50 J) on a single application, with one dose per stage at 7-day intervals between stages. PBMT–SMF was applied with a cluster of 12 diodes (4 of 905 nm laser, 4 of 875 nm LEDs, and 4 of 640 nm LEDs, SMF of 35 mT) at 17 sites on both lower limbs after baseline evaluation: plantar flexors (2), knee extensors (9), and flexors (6). The primary outcome was self-selected walking speed, and the secondary outcomes were kinematic parameters. Gait analysis was performed using SMART-D 140^® and SMART-D INTEGRATED WORKSTATION^®. The outcomes were measured at the end of each stage after the single application of each PBMT–SMF dose tested. Results: No significant differences (p > 0.05) in spatiotemporal variables were observed between the different doses, compared with the baseline evaluation. However, differences (p < 0.05) were observed in the kinematic variable of the hip in the paretic and non-paretic limbs, specifically in the minimum flexion/extension angulation during the support phase (HMST–MIN) in doses 10 J, 30 J, and 50 J. Conclusions: A single application of PBMT–SMF at doses of 10 J, 30 J, and 50 J per site of the lower limbs did not demonstrate positive effects on the spatiotemporal variables, but it promoted immediate effects in the kinematic variables of the hip (maximum and minimum flexion/extension angulation during the support phase) in the paretic and non-paretic limbs in post-stroke people.

Efficacy of an exoskeleton-based physical therapy program for non-ambulatory patients during subacute stroke rehabilitation: a randomized controlled trial

BACKGROUND

Individuals requiring greater physical assistance to practice walking complete fewer steps in physical therapy during subacute stroke rehabilitation. Powered exoskeletons have been developed to allow repetitious overground gait training for individuals with lower limb weakness. The objective of this study was to determine the efficacy of exoskeleton-based physical therapy training during subacute rehabilitation for walking recovery in non-ambulatory patients with stroke.

METHODS

An assessor-blinded randomized controlled trial was conducted at 3 inpatient rehabilitation hospitals. Patients with subacute stroke (< 3 months) who were unable to walk without substantial assistance (Functional Ambulation Category rating of 0 or 1) were randomly assigned to receive exoskeleton-based or standard physical therapy during rehabilitation, until discharge or a maximum of 8 weeks. The experimental protocol replaced 75% of standard physical therapy sessions with individualized exoskeleton-based sessions to increase standing and stepping repetition, with the possibility of weaning off the device. The primary outcome was walking ability, measured using the Functional Ambulation Category. Secondary outcomes were gait speed, distance walked on the 6-Minute Walk Test, days to achieve unassisted gait, lower extremity motor function (Fugl-Meyer Assessment), Berg Balance Scale, Patient Health Questionnaire, Montreal Cognitive Assessment, and 36-Item Short Form Survey, measured post-intervention and after 6 months.

RESULTS

Thirty-six patients with stroke (mean 39 days post-stroke) were randomized (Exoskeleton = 19, Usual Care = 17). On intention-to-treat analysis, no significant between-group differences were found in the primary or secondary outcomes at post-intervention or after 6 months. Five participants randomized to the Exoskeleton group did not receive the protocol as planned and thus exploratory as-treated and per-protocol analyses were undertaken. The as-treated analysis found that those adhering to exoskeleton-based physical therapy regained independent walking earlier (p = 0.03) and had greater gait speed (p = 0.04) and 6MWT (p = 0.03) at 6 months; however, these differences were not significant in the per-protocol analysis. No serious adverse events were reported.

CONCLUSIONS

This study found that exoskeleton-based physical therapy does not result in greater improvements in walking independence than standard care but can be safely administered at no detriment to patient outcomes. Clinical Trial Registration The Exoskeleton for post-Stroke Recovery of Ambulation (ExStRA) trial was registered at ClinicalTrials.gov (NCT02995265, first registered: December 16, 2016).

Comfortable walking speed and energy cost of locomotion in patients with multiple sclerosis

Comfortable walking speed and energy cost of walking are physiological markers of metabolic activity during gait. People with multiple sclerosis are characterized by altered gait biomechanics and energetics, related to the degree of disability and spasticity, which lead to an increased energy cost of walking. Several studies concerning the energy cost of walking in multiple sclerosis have been published. Nevertheless, differences in protocols and characteristics of the sample have led to different outcomes. The aim of the present meta-analysis is to summarize results from studies with specific inclusion characteristics, and to present data about the comfortable walking speed and the energy cost of walking at that speed. Moreover, a detailed discussion of the potential mechanisms involved in the altered metabolic activity during exercise was included. A total of 19 studies were considered, 12 of which were also part of the quantitative analysis. Despite the strict selection process, high between-group heterogeneity was found for both outcomes. Nevertheless, the overall results suggest a pooled mean comfortable walking speed of 1.12 m/s (95% CI 1.05-1.18) and energy cost of 0.19 mLO₂/kg/m (95% CI 0.17-0.21). These findings support the results of previous studies suggesting that energy cost of walking may be increased by 2-3 times compared to healthy controls (HC), and encourage the use of this marker in association with other parameters of the disease.