Duration Of Single Limb Support Research Articles

On the clinical interpretation of overground gait stability indices in children with cerebral palsy

Several indices have been devised to quantify a person’s stability from its gait pattern during overground walking. However, clinical interpretation of the indices is difficult because the link between being stable and adopting a mechanically stable gait pattern may not be straightforward. This is particularly true for one of these indices, the margin of stability, for which opposite interpretations are available in the literature. We collected overground walking data in two groups of 20 children, with unilateral cerebral palsy (CP) and typically developing (TD), for two conditions, on flat and on uneven grounds (UG). We postulated that TD children were more stable during gait than children with CP and that both groups were more stable on flat compared to UG. We explored the coherent association between several indices and the two postulates to clarify clinical interpretation. Our results showed that increased margin of stability, increased amplitude of the whole-body angular momentum, decreased duration of single limb support, increased variability (gait kinematics, step length, and step width) were associated with reduced stability for both postulates. However, results for the margin of stability were paradoxical between the sides in the CP group where small margin of stability was indicative of a fall forward strategy on the affected side rather than improved stability. Whole-body angular momentum and duration of single limb support appeared as the most sensitive indices. However, walking speed influenced these and would need to be considered when comparing groups of different walking speed.

The Immediate Effect of the Novel Hybrid Passive Spring Damper Ankle-Foot Orthosis on Spatiotemporal Parameters of Walking in Patients with Multiple Sclerosis

ABSTRACT Introduction Patients with multiple sclerosis (PwMS) experience damage to their central nervous system, which can lead to unilateral or bilateral drop foot. The presently utilized ankle-foot orthoses (AFOs) for PwMS have exhibited limited clinical efficacy. Objective This current study evaluated the immediate effects of the Novel Hybrid Passive Spring Damper Ankle-Foot Orthosis (HPSDAFO) on walking in PwMS. Study design A cohort trial. Methods Twelve PwMS suffering of unilateral drop foot took part in this study. They were given the novel HPSDAFO and underwent kinematic assessment including walking along a 10-m walkway at a self-selected speed, both with and without the HPSDAFO. Results The novel HPSDAFO device significantly changed gait parameters of ankle range of motion, single limb support duration, and step and stride length of the affected side (P < 0001). Furthermore, the device also improved the symmetry index and resulted in increased walking speed and cadence. Conclusions The application of the novel HPSDAFO on the affected side of PwMS resulted in a notable enhancement in the symmetry of spatial parameters, which highlights the need for additional research in this area. Clinical Relevance Using the novel HPSDAFO, PwMS can walk without adverse effects, promoting the normalization of their spatiotemporal walking parameters.

The effects of improvement in upper extremity function on gait and balance in children with upper extremity affected

BackgroundThis study aimed to investigate the effects of functional improvement in the upper extremity on gait and balance in children with upper extremity affected. Research questionWhat are the effects of functional improvement in the upper extremity on gait and balance in children with upper extremity affected? MethodsEighteen children with a diagnosis of rheumatologic diseases and 15 healthy children were evaluated with Shriners Hospital Upper Extremity Assessment, Jebsen-Taylor Hand Function Test, Abilhand Rheumatoid Arthritis Scale, 10-meter walk test and Childhood Health Assessment Questionnaire. For static balance assessment, the Biodex Balance was used. Ground reaction forces (peak forces (heel strike and push-off) and minimum force (loading response), single-limb support duration, Center-of-Force displacement and walking speed were evaluated with the Sensor Medica. Arm swing was evaluated with the Kinovea 2D motion analysis. ResultsBefore treatment, single-limb support duration and push-off force was higher and center-of-force displacement was lower on affected side compared to unaffected side in rheumatologic group. After the 6-week rehabilitation program, upper extremity function, quality of life and functional gait score improved. Single-limb support duration decreased on affected side and increased on unaffected side. On affected side, push-off force decreased. The arm swing parameters were similar before and after treatment. SignificanceImproving upper extremity function can help with gait balance by decreasing the difference in walking and balance parameters between the affected and unaffected sides and providing for more symmetrical weight transfer.

Gait asymmetry pattern following stroke determines acute response to locomotor task

BackgroundGiven the prevalence of gait dysfunction following stroke, walking recovery is a primary goal of rehabilitation. However, current gait rehabilitation approaches fail to demonstrate consistent benefits. Gait asymmetry, prevalent among stroke survivors who regain the ability to walk, is associated with an increased energy cost of walking and is a significant predictor of falls post-stroke. Furthermore, differential patterns of gait asymmetry may respond differently to gait training parameters. Research questionThe purpose of this study was to determine whether differential responses to locomotor task condition occur on the basis of step length asymmetry pattern (Symmetrical, NPshort, Pshort) observed during overground walking. MethodsParticipants first walked overground at their self-selected walking speed. Overground data were compared against three task conditions all tested during treadmill walking: self-selected speed with 0% body weight support (TM); self-selected speed with 30 % body weight support (BWS); and fastest comfortable speed with 30 % body weight support and nonparetic leg guidance (GuidanceNP). Our primary metrics were: symmetry indices of step length, stride length, and single limb support duration. ResultsWe identified differences in the response to locomotor task conditions for each step length asymmetry subgroup. GuidanceNP induced an acute spatial symmetry only in the NPshort group and temporal symmetry in the Symmetrical and Pshort groups. Importantly, we found the TM and BWS conditions were insufficient to impact either spatial or temporal gait symmetry. SignificanceTask conditions consistent with locomotor training do not produce uniform effects across subpatterns of gait asymmetry. We identified differential responses to locomotor task conditions between groups with distinct asymmetry patterns, suggesting these subgroups may require unique intervention strategies. Despite group differences in asymmetry characteristics, improvements in symmetry noted in each group were driven by changes in both the paretic and nonparetic limbs.

Effects of Gait Training With Body Weight Support on a Treadmill Versus Overground in Individuals With Stroke

ObjectiveTo investigate the effects of gait training with body weight support (BWS) on a treadmill versus overground in individuals with chronic stroke. DesignRandomized controlled trial. SettingUniversity research laboratory. ParticipantsIndividuals (N=28) with chronic stroke (>6mo from the stroke event). InterventionsParticipants were randomly assigned to receive gait training with BWS on a treadmill (n=14) or overground (n=14) 3 times a week for 6 weeks. Main Outcome MeasuresGait speed measured using the 10-meter walk test, endurance measured using the 6-minute walk test, functional independence measured using the motor domain of the FIM, lower limb recovery measured using the lower extremity domain of the Fugl-Meyer assessment, step length, step length symmetry ratio, and single-limb support duration. Measurements were obtained at baseline, immediately after the training session, and 6 weeks after the training session. ResultsAt 1 week after the last training session, both groups improved in all outcome measures except paretic step length and step length symmetry ratio, which were improved only in the overground group (P=.01 and P=.01, respectively). At 6 weeks after the last training session, all improvements remained and the treadmill group also improved paretic step length (P<.001) but not step length symmetry ratio (P>.05). ConclusionsIndividuals with chronic stroke equally improve gait speed and other gait parameters after 18 sessions of BWS gait training on either a treadmill or overground. Only the overground group improved step length symmetry ratio, suggesting a role of integrating overground walking into BWS interventions poststroke.

Postural Instability and Gait Impairment During Obstacle Crossing in Parkinson's Disease

Stegemöller EL, Buckley TA, Pitsikoulis C, Barthelemy E, Roemmich R, Hass CJ. Postural instability and gait impairment during obstacle crossing in Parkinson's disease. ObjectiveTo examine whether Parkinson's disease (PD) affects gait behavior and stability while walking over an obstacle. DesignParallel group comparisons were completed in which participants completed 5 trials of normal walking and 5 trials of obstacle crossing while gait kinematics and kinetics were collected. SettingUniversity biomechanics laboratory. ParticipantsIndividuals with PD (n=10) and age- and sex-matched healthy older adults (n=10). InterventionsNot applicable. Main Outcome MeasuresGait parameters, obstacle clearance parameters, and center of mass motion were calculated during normal walking and obstacle crossing. ResultsResults revealed that decrements in gait performance in individuals with PD were amplified during obstacle crossing, suggesting that due to disease-related degradation, individuals with PD chose a more conservative strategy for obstacle crossing. Moreover, an increased duration of single limb support (18% increase), a decrease in anteroposterior range of motion (20% decrease), and an increase in mediolateral range of motion (36% increase, though not significant) coupled with the reduction in the distance between the center of pressure and center of mass (mean of 21% decrease across toe-off and heel strike) and increase in margin of stability (31% increase at toe-off and 71% increase at heel strike) may suggest that deficits in muscle strength and balance may contribute to this impairment. ConclusionsPersons with PD alter their behavior to reduce the mechanical demands and increase dynamic stability during obstacle avoidance tasks.

Effects of the addition of functional electrical stimulation to ground level gait training with body weight support after chronic stroke

The addition of functional electrical stimulation (FES) to treadmill gait training with partial body weight support (BWS) has been proposed as a strategy to facilitate gait training in people with hemiparesis. However, there is a lack of studies that evaluate the effectiveness of FES addition on ground level gait training with BWS, which is the most common locomotion surface. To investigate the additional effects of commum peroneal nerve FES combined with gait training and BWS on ground level, on spatial-temporal gait parameters, segmental angles, and motor function. Twelve people with chronic hemiparesis participated in the study. An A1-B-A2 design was applied. A1 and A2 corresponded to ground level gait training using BWS, and B corresponded to the same training with the addition of FES. The assessments were performed using the Modified Ashworth Scale (MAS), Functional Ambulation Category (FAC), Rivermead Motor Assessment (RMA), and filming. The kinematics analyzed variables were mean walking speed of locomotion; step length; stride length, speed and duration; initial and final double support duration; single-limb support duration; swing period; range of motion (ROM), maximum and minimum angles of foot, leg, thigh, and trunk segments. There were not changes between phases for the functional assessment of RMA, for the spatial-temporal gait variables and segmental angles, no changes were observed after the addition of FES. The use of FES on ground level gait training with BWS did not provide additional benefits for all assessed parameters.

Light Touch Cue Through a Cane Improves Pelvic Stability During Walking in Stroke

Boonsinsukh R, Panichareon L, Phansuwan-Pujito P. Light touch cue through a cane improves pelvic stability during walking in stroke. Objective To examine the effect of a light touch cue provided through a cane on mediolateral (ML) pelvic stability during walking in subjects poststroke. Design Crossover trial examining ML pelvic stability during walking using a cane with the force contact and touch contact methods. Setting Physical therapy clinic, tertiary care center. Participants Subacute patients (N=40) with stroke with a mean age of 59.6 years and mean stroke duration of 46.8 days. The average gait speed with a cane was .13m/s (.05–.29m/s). Intervention Using a cane with the force contact and touch contact methods during walking. Main Outcome Measures ML pelvic stability as measured by averaged peak-to-peak pelvic acceleration, muscle activation of bilateral tensor fascia latae (TFL), semitendinosus (ST), and vastus medialis (VM) using an electromyography system, and vertical cane force. Results The average amount of cane force during touch contact and force contact cane use conditions was 2.3N and 49.3N, respectively. A light touch cue through a cane was required only when the paretic leg accepted the body weight, and this cue can provide ML pelvic stability (.16g of average pelvic acceleration) during walking to the same degree as the force contact method of cane use. However, significant increases in single-limb support duration with higher activations of TFL, VM, and ST muscles on the paretic leg were found during the paretic stance phase when using a cane in the touch contact fashion ( P<.05). Conclusions A light touch cue can be provided during walking through the use of a cane. This augmented somatosensory information provides lateral stability during walking for subjects with stroke by facilitating the activations of weight-bearing muscles on the paretic leg during the stance phase.

Gait synchronized force modulation during the stance period of one limb achieved by an active partial body weight support system

Our purpose was to demonstrate the ability of an actively controlled partial body weight support (PBWS) system to provide gait synchronized support during the stance period of a single lower extremity while examining the affect of such a support condition on gait asymmetry. Using an instrumented treadmill and a motion capture system, we compared gait parameters of twelve healthy elderly subjects (age 65–80 years) during unsupported walking to those while walking with 20% body weight support provided during only the stance period of the right limb. Specifically, we examined peak three-dimensional ground reaction force (GRF) data and the symmetry of lower extremity sagittal plane joint angles and of time and distance parameters. A reduction in all three GRF components was observed for the supported limb during modulated support. Reductions observed in the vertical GRF were comparable to the desired 20% support level. Additionally, GRF components examined for the unsupported limb during modulated support were consistently similar to those measured during unsupported walking. Modulated support caused statistically significant increases in asymmetry for knee flexion during stance (increased 5.9%), hip flexion during late swing (increased 9.1%), and the duration of single limb support (increased 2.8%). However, the observed increases were similar or considerably less than the natural variability in the asymmetry of these parameters during unsupported walking. The ability of the active PBWS device to provide unilateral support may offer new and possibly improved applications of PBWS rehabilitation for patients with unilateral walking deficits such as hemiparesis or orthopaedic injury.

Comparing stepping-in-place and gait ability in adults with and without hemiplegia

Garcia RK, Nelson AJ, Ling W, Van Olden C. Comparing stepping-in-place and gait ability in adults with and without hemiplegia. Arch Phys Med Rehabil 2001;82:36-42. Objective: To determine and compare select temporal-distance measures of stepping-in-place with gait ability in 2 age-matched groups. Design: Repeated measures, matched research design. Setting: Gait laboratory and hospital outpatient unit. Participants: Convenience sample recruited from within the community and the outpatient unit of a local rehabilitation hospital included 30 healthy adults (age range, 58.1 ± 10.8yr) and 30 age-matched adults with hemiplegia (age range, 58.6 ± 10.3yr), secondary to a cerebrovascular accident. Interventions: Subjects were videotaped in the sagittal plane performing stepping-in-place and while walking. Select temporal-distance measures obtained by manual calculations from the video recordings were determined for 3 20-second trials of each activity. Main Outcome Measures: Single limb support duration (SLSD) of the lower extremities (LEs) and step frequency during stepping-in-place and during gait. Results: A significant difference was found between the step frequency of each activity for the adults with hemiplegia (p <.05), but not for the healthy adults. A significant difference was also found between SLSD of the same LE across activities for each group (p <.05). SLSD of each LE during each individual activity, stepping-in-place, or gait, was not significantly different for the healthy adults, indicating LE symmetry; but it was significantly different for the adults with hemiplegia (p <.05), indicating LE asymmetry. Conclusions: Stepping-in-place incorporates reciprocal, rhythmic LE movement patterns similar to gait. And, although SLSD of the LEs was different between the activities in both groups, each group showed similar LE movement patterns during each individual activity. In addition, step frequency was consistent between the activities for the healthy adults. These results seem to indicate that the reciprocal, rhythmic LE movement patterns, which are invoked during gait, may also be invoked during stepping-in-place. However, further research is needed to enhance the data related to stepping-in-place and gait ability in clinical populations. © 2001 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation

Retest Reliability of the Temporal and Distance Characteristics of Hemiplegic Gait Using a Footswitch System

Using a footswitch system, the retest reliability of the temporal and distance parameters of gait was investigated within a session for 22 stroke patients in the early phase of rehabilitation. High to very high reliability was found for the temporal and distance parameters of gait, and the temporal symmetry index based on the difference in single-limb support duration between each leg (r = 0.85 to 0.98; intraclass correlation coefficients (ICC)(2,1) = 0.82 to 0.98). Significant differences were found between the two trials for velocity, stride length, and total double support (p < .05). Despite the high reliability coefficients, 95% confidence intervals, which take into account the random and systematic error, were wide for all parameters. These wide confidence intervals indicate that the use of two consecutive measurements for interpreting an individual patient's change would not be a sensitive method for monitoring progress or deterioration during rehabilitation. Strategies that may improve the clinical usefulness of temporal and distance gait measures in stroke rehabilitation are discussed. These include further reducing error sources, increasing data collection per measurement, using serial measurements on each patient, or using less rigorous confidence intervals.