Kinematic and kinetic asymmetries in hemiplegic patients' gait initiation patterns.

OBJECTIVE: To assess the kinetic and kinematic characteristics of hemiplegic stroke patients' gait initiation patterns during the various gait initiation phases. DESIGN AND SUBJECTS: Gait initiation was studied in 3 hemiplegic subjects with a spastic equinus varus foot and 3 control subjects. METHODS: Temporal and kinetic analysis of gait initiation was performed with 2 AMTI force plates, and kinematic analysis of gait initiation with an ELITE optoelectronic system. A one-way ANOVA was performed directly on the phase durations, forces, centre of pressure displacements, stride length, and ankle motion range. RESULTS: Duration of the monopodal phase was shorter in hemiplegic patients when the affected leg rather than the sound one was used as the supporting leg. Propulsion forces were exerted by the hemiplegic patients' sound leg during the postural phase. Hemiplegic patients' body weight was supported more by the sound leg than by the affected leg. Knee was lifted higher on the affected side during the swing phase to compensate for the equinus. Initial contact was performed with a flat foot on the affected side. CONCLUSION: Quantitative data obtained on the gait initiation phase suggest that hemiplegic patients develop asymmetrical adaptive posturo-motor strategies to compensate for their impairments.     

Reorganization of equilibrium and movement control strategies in patients with knee arthritis

The purpose of this study was to identify changes in equilibrium and movement control strategies in patients with arthritis of the knee. These strategies were expected to be different from those of healthy subjects because of the impairments caused by knee arthritis. The different phases of a side step were studied in patients with severe knee arthritis using a movement analysis system and force-plates. The duration of the postural phase and the intensity of the horizontal ground reaction forces during the postural phase were increased when the pathological limb was the supporting one. The monopodal phase was shortened on the pathological leg. These results show that knee arthritis patients develop new posturomotor strategies mainly aimed at shortening the monopodal phase when the affected leg is the supporting one. This movement analysis method enables quantification of differences that cannot be observed on clinical examination between knee arthritis patients and control subjects, and provides additional information to the usual clinical evaluation scales.     

Asymétries chronométriques, cinétiques et cinématiques de l''initiation de la marche chez un sujet hémiplégique

OBJECTIVE: To investigate the temporal, kinetic and kinematic asymmetry of gait initiation in one subject with hemiplegia with an equinus varus foot. MATERIAL AND METHODS: A kinetic analysis with two AMTI force plates and a kinematic analysis with an ELITE optoelectronic system of gait initiation were performed in one subject with hemiplegia. RESULTS: The duration of the gait initiation phases was asymmetrical. The monopodal phase was shorter when the affected lower limb was supporting than when the healthy one was supporting. The propulsion resulted from the force exerted on the healthy lower limb. The distribution of body weight on the lower limbs was asymmetrical. Body weight support was more important on the healthy side than on the affected side. Maximal extension of the ankle on the hemiplegic side occurred during the swing phase. Ground clearance was increased by elevating the knee higher on the affected side than on the healthy side during the swing phase. Initial contact with the floor was performed with the foot flat on the affected side. CONCLUSION: This preliminary study has shown that gait initiation in one subject with hemiplegia was asymmetrical in kinetics and kinematics. The results concerning kinematics have not been reported previously for gait initiation in subjects with hemiplegia. The study of gait initiation should allow for better understanding postural and movement control strategies developed by patients with hemiplegia.     

Gait performance with compensatory adaptations in stroke patients with different degrees of motor recovery

OBJECTIVE: Gait patterns vary among stroke patients. This study attempted to discover gait performance with compensatory adaptations in stroke patients with different degrees of motor recovery. DESIGN: Data were gathered from 35 stroke patients and 15 healthy subjects. Gait performance and motor recovery were assessed 6 mos after stroke. Stroke patients further were divided into poor and good groups. The walking velocity was correlated with Brunnstr?m's stages, and the temporal stride and motion variables of the two groups were compared. RESULTS: Walking velocity was positively correlated with the Brunnstr?m's stages of the proximal lower limb. The poor group displayed slower walking velocity and shorter single-support time compared with the good group. Both groups displayed low maximum excursion of hip extension and ankle plantarflexion during the stance phase and low maximum excursion of hip and knee flexion and ankle dorsiflexion during the swing phase. Moreover, both groups displayed excessive pelvic tilts during the stance and swing phases. However, the poor group displayed different pelvic motion and timing sequences to each peak joint angle from normal subjects and the good group. Peak hip and knee angles of the affected limb during the stance phase occurred almost simultaneously in this group. CONCLUSIONS: Selective control of the proximal lower limb may be the main determinant of walking velocity. The compensatory adaptations were similar, except for pelvic motion, in stroke patients with different levels of motor recovery, whereas the poor group walked with synergistic mass patterns and reduced stability.     

What is the influence of severity levels of knee osteoarthritis on gait initiation?

BackgroundThe anticipatory postural adjustments required for gait initiation have not yet been investigated in older adults with different levels of severity of knee osteoarthritis. This study aimed to evaluate the anticipatory postural adjustments adopted by older adults with different severity levels of knee osteoarthritis during gait initiation.MethodsSixty-seven older adults with knee osteoarthritis (mild, moderate, and severe levels) and 11 healthy older adults control were evaluated bilaterally with a force plate to analyze gait initiation. The center of pressure trajectory during gait initiation was divided into four phases: three anticipatory postural adjustments, and a locomotor phase. The length, duration, and velocity of each phase were calculated.FindingsThe results showed that during the right and left limbs swing forward, the severe and moderate knee osteoarthritis groups presented a significant reduction in the length of anticipatory postural adjustment phases, locomotion, duration, and velocity (P < 0.05). The severe knee osteoarthritis group presented a significantly higher body mass index (P < 0.003) than the other groups. However, just the healthy group presented a correlation between body mass index and anticipatory postural adjustments.InterpretationOur results demonstrated that older adults with severe and moderate levels of knee osteoarthritis adopt longer lasting and slower anticipatory postural adjustment phases, lower locomotion, and lower center of pressure displacement during gait initiation, suggesting that this population has adaptive strategy in performing gait initiation, which is significantly changed by the knee osteoarthritis severity level.     

人体起步过程的实验研究——平地行走的起步步态特征

目的：研究人体平地行走的起步过程步态特征,方法：使用基于CCD和三维测力平台的人体运动分析系统,研究正常人水平地面起步过程的步态特征,结果：描述,分析了完整起步过程各步相的特征以及地面对足的三维反作用力规律,结论：／起步过程在第二次摆动腿触地时结束,开始进入稳定步行状态,起步时支撑腿对起步驱动力贡献最大。     

Gait initiation and lateral wedge insole for individuals with early knee osteoarthritis

BackgroundPeople with knee osteoarthritis are at higher risk of postural deficits and locomotor adaptations which could be manifested in transient tasks like gait initiation. To better understand the effect of early knee osteoarthritis on gait initiation, we measured the gait initiation in two groups of early knee osteoarthritis and healthy age-matched controls and assessed the effect of lateral wedge insole in knee osteoarthritis group.MethodsTwenty-one individuals with early knee osteoarthritis, mean (SD) age = 53.1 (7.4, years), and 19 age- and sex-matched asymptomatic healthy individuals, mean (SD) age = 47.5 (11.2, years), participated. Centre of pressure trajectories were used to quantify the two phases of gait initiation in barefoot condition: anticipatory postural adjustment, and locomotor phase. The immediate and four-week effect of lateral wedge insole and shod condition were also compared for individuals in knee osteoarthritis group.FindingsLonger duration of anticipatory postural adjustment phase (P = 0.046), locomotor phase (P = 0.049), and total duration of gait initiation (P = 0.035) with lower length and velocity of the center of pressure trajectories in anticipatory postural adjustment phase (P = 0.002, and 0.008, respectively) were observed in knee osteoarthritis group compared to controls. Lateral wedge insole could increase the length and velocity of the centre of pressure in locomotor phase compared to barefoot condition (P = 0.001, and 0.002, respectively).InterpretationOur study outlined that people with early knee osteoarthritis adopt different gait initiation strategies mainly in postural preparation phase. The potential effect of lateral wedge insole was shown with better performance of the locomotor phase.Clinical trial registry numberIRCT2016060628310N1.     

Biomechanical consequences of a knee osteoarthritis on the opposite lower limb]

The aim of this work was to study the compensatory strategies built up by patients with unilateral knee arthritis during stair descent. These compensatory strategies might induce increased biomechanical constraints on the unaffected knee. METHOD: A kinetic and kinematic analysis was performed in 11 patients with unilateral knee arthritis and in 14 control subjects using an ELITE system and two force-plates. The peak of vertical ground reaction forces when landing on the reception force-plate, the time to reach the peak and the duration of the different phases of the movement were studied during stair descent. RESULTS: The peak of vertical ground reaction forces was more important when landing on the unaffected limb than when landing on the affected limb. The time to reach this peak was longer in patients than in controls no matter which side was supporting. The duration of the single support phase was longer on the unaffected limb than on the affected limb. DISCUSSION AND CONCLUSION: This work has shown that patients with unilateral knee arthritis develop new strategies during stair descent. These new strategies imply increased biomechanical constraints on the unaffected limb and might favor arthritis on the sound side. These results support the idea that rehabilitation protocols of patients with unilateral knee arthritis should also involve the unaffected limb.     

Effects of increasing non-paretic step length on paretic leg movement during hemiparetic gait: a pilot study

[Purpose] Gait training that increases non-paretic step length in stroke patients increases the propulsive force of the paretic leg. However, it limits knee flexion during the swing phase of gait, and this may cause gait disturbances such as worsening of gait pattern and increased risk of falling. Therefore, this study aimed to investigate the effects of increasing non-paretic step length on the joint movement and muscle activity of a paretic lower limb during hemiparetic gait. [Participants and Methods] A total of 15 hemiparetic patients with chronic stroke were enrolled in this study. Spatiotemporal parameters, along with kinematic and electromyography data of their paretic lower limbs, were measured during a 10-m distance overground walking. Two walking conditions were assessed: normal (comfortable gait) and non-paretic-long (gait with increased non-paretic step length) conditions. [Results] Under the non-paretic-long condition, the trailing limb angle was larger than under the normal condition. However, no significant difference was observed in the knee flexion angle during the swing phase. [Conclusion] Increasing non-paretic step length during gait is unlikely to limit knee flexion during the swing phase and can safely improve the propulsive force of a paretic leg.     

Rate and range of knee motion during ambulation in healthy and arthritic subjects

The purpose of this study was to determine the relationship between gait velocity and rate and range of knee motion, during ambulation, for healthy and arthritic subjects. The arthritic subjects had either rheumatoid arthritis or osteoarthritis, and all were tested before and after total knee replacement. Healthy subjects ambulated at an average velocity of 80 m/min and demonstrated knee flexion and extension rates of 344 degrees/sec and a range of knee motion of 60 degrees. Gait velocity correlated with rates of knee flexion and extension and range of knee motion. Arthritic subjects ambulated at velocities less than those of healthy subjects ambulating at free speed. Arthritic subjects accordingly demonstrated reduced knee flexion and extension rates and range of knee motion. When compared with healthy subjects ambulating over a comparable gait-velocity range, the arthritic subjects demonstrated reduced rates and range of motion in most instances. We discuss implications for therapeutic intervention to increase gait velocity for arthritic subjects.     

Three dimensional gait analysis and controlling spastic foot on stroke patients]

INTRODUCTION: The purpose of this work is to assess the interest of three dimensional gait analysis in measuring the effect of orthesis and of selective tibial neurotomy without visual analysis. METHOD: After clinical examination, gait in the two groups was recorded by a three dimensional motion system (Vicon-Oxford Metrics) with free velocity. The gait of ten stroke patients was compared bare-foot and with ankle-foot orthesis. The gait of nine stroke patients was compared bare-foot before and six month after selective tibial neurotomy. Kinematics data were studied in the sagittal plane, and muscular electrical activity was detected on the affected side by a ten-channel telemetry system using surface electrodes. An analogic visual scale ( EVA) was used by the patient, to assess discomfort during walking. RESULTS: In the "orthesis" group, calf spasticity was 2.5 on the Ashworth scale. With ankle-foot orthesis, the walking discomfort on EVA was significantly reduced from 4.25 to 1.16. Gait speed increased significativelly at 0.42 m s(-1) to 0.59 m s(-1). In swing phase, equinus disappeared. In stance phase equinus and recurvatum were controlled, anterior pelvic tilt decreased and hip extension increased. In the "neurotomy" group, 6 months after the tibial neurotomy, calf spasticity decreased from 3.4 to 0. The walking discomfort on EVA, was significantly reduced from 5.97 to 3.6. Gait speed increased from 0.51 m s(-1) to 0.54 m s(-1). Ankle dorsiflexion on the affected side, was possible during stance for five patients and residual motricity was released during swing phase for two patients. Stance knee recurvatum was corrected in five patients. CONCLUSION: Three dimensional analysis specifies the functional gait disability in stroke patients. It specifies the degree of correction provided by orthesis or tibial neurotomy in the various gait cycle phases and the impact on the superior joints.     

A textured insole improves gait symmetry in individuals with stroke

Abstract

Purpose: Gait asymmetry is a common consequence of stroke and improving gait symmetry is an important goal of rehabilitation. We investigated the effect of a single textured insole in improving gait symmetry in individuals with stroke.

Method: Seventeen individuals with stroke who had asymmetrical gait were recruited and required to walk with a textured insole positioned in the shoe on the unaffected side or without the insole. Gait parameters were evaluated using the instrumented walkway. Gait velocity, cadence, and symmetry indices for the spatial and temporal parameters of gait and center of pressure displacements were obtained.

Results: When walking with a textured insole, symmetry indexes for stance, single support phases of gait, as well as center of pressure displacements improved significantly. While using a textured insole, the duration of the stance phase and a single support phase decreased on the unaffected side and increased on the affected side significantly. Gait velocity and cadence were not affected by the use of the insole.

Conclusions: Individuals with stroke walking with a textured insole placed in the shoe on the unaffected side improved the symmetry of their gait. The outcome provides a foundation for future investigations of the efficacy of using a single textured insole in gait rehabilitation of individuals with unilateral impairment.

• Implications for Rehabilitation

• A single textured insole positioned in the shoe on the unaffected side improved gait symmetry in individuals with stroke.

• Gait velocity and cadence were not affected by the use of the insole.

     

The gait initiation process in unilateral lower-limb amputees when stepping up and stepping down to a new level

BACKGROUND: Unilateral lower-limb amputees lead with their intact limb when stepping up and with their prosthesis when stepping down; the gait initiation process for the different stepping directions has not previously been investigated. METHODS: Ten unilateral amputees (5 transfemoral and 5 transtibial) and 8 able-bodied controls performed single steps up and single steps down to a new level (73 and 219 mm). Duration, a-p and m-l centre of mass and centre of pressure peak displacements and centre of mass peak velocity of the anticipatory postural adjustment and step execution phase were evaluated for each stepping direction by analysing data collected using a Vicon 3D motion analysis system. FINDINGS: There were significant differences (in the phase duration, peak a-p and m-l centre of pressure displacement and peak a-p and m-l centre of mass velocity at heel-off and at foot-contact) between both amputee sub-groups and controls (P<0.05), but not between amputee sub-groups. These group differences were mainly a result of amputees adopting a different gait initiation strategy for each stepping direction. INTERPRETATION: Findings indicate the gait initiation process utilised by lower-limb amputees was dependent on the direction of stepping and more particularly by which limb the amputee led with; this suggests that the balance and postural control of gait initiation is not governed by a fixed motor program, and thus that becoming an amputee will require time and training to develop alternative neuromuscular control and coordination strategies. These findings should be considered when developing training/rehabilitation programs.     

Kinematic effects of different gait speeds during gait initiation movement

[Purpose] We investigated the influence of gait speed on the movement strategy during gait initiation. [Participants and Methods] This study included 21 young healthy individuals (11 males and 10 females; mean age, 21.7 ± 0.5 years; mean height, 166.1 ± 9.8 cm; and mean weight, 57.3 ± 11.2 kg). A three-dimensional motion analyzer and strain gauge force platform were used in this study. The measurement task consisted of gait initiation from the quiet stance; the two measurement conditions were normal gait and the highest speed. The analysis interval was from the start of the center of pressure migration to the heel contact at the first step of the swing limb. The center of gravity, center of pressure, joint movements, step length, and step time during the anticipatory postural control (from the start of center of pressure migration to swing leg-heel off) and swing (swing leg-heel off to swing leg-heel contact) phases were analyzed. [Results] Significant differences were observed in the center of gravity, center of pressure, hip flexion, abduction movement, stance-limb ankle dorsiflexion movement during the anticipatory postural control phase, and step time during the anticipatory postural control and swing phases. The stance-limb ankle plantar flexion movement and step length did not differ significantly in the swing phase. [Conclusion] When the gait speed increases, fluctuations in the joint movements increase as the center of pressure displacement increases, thus requiring complex control.     

Preliminary evaluation of an automatically stance-phase controlled pediatric prosthetic knee joint using quantitative gait analysis

OBJECTIVES: To evaluate the effects on gait of a new pediatric prosthetic knee joint using an automatic stance-phase lock (ASPL), shown previously to help prevent falls, and to propose future design considerations and prosthetic alignments. DESIGN: Case series and crossover trial. SETTING: Human movement laboratory. PARTICIPANTS: Three children with unilateral above-knee amputations and 3 children with bilateral above-knee or below-knee amputations. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Spatiotemporal, kinematic, and kinetic gait parameters. RESULTS: Spatiotemporal parameters indicated higher gait velocities with the ASPL knee joint for the children with unilateral amputations. The increased speed, as expected, was associated with increased temporal interlimb asymmetry, joint moments and powers, and excessive prosthetic knee range of motion in swing. A trend toward increased pelvic motions was observed with ASPL knee when compared with conventional knees. CONCLUSIONS: The biomechanic performance of the single-axis ASPL knee joint was shown to be comparable with more complex polycentric pediatric prosthetic knee joint technologies worn by the children in this study.     

Gait and electromyographic analysis of patients recovering after limb-saving surgery

OBJECTIVE: Control of gait after limb-saving surgery.Design. Case series study. BACKGROUND: At the moment little is known about adaptations in patients' gait after limb-saving surgery. METHODS: Nineteen patients who underwent limb-saving surgery at least 1 yr earlier and 10 normal subjects were studied during treadmill walking. The main outcome measures were walking speed, step parameters and angular displacement of both legs and EMG of the biceps femoris, rectus femoris and medial gastrocnemius in the affected leg. RESULTS: Preferred walking speed in the patients was lower than in the controls (0.7 versus 1.1 m/s). Furthermore, stance phase of the non-affected leg was lengthened. All patients showed reduced stance phase knee flexion in the affected leg, while during the swing phase no difference was seen. The EMG signals of the rectus femoris and biceps femoris show changes, which are related to the location of surgery. CONCLUSIONS: The results showed that the gait pattern of the patients differed compared to normal gait. The reduced stance phase knee flexion in the hip group is based on a high degree of co-contraction between quadriceps and hamstring activity, while in the knee group this is based on the quadriceps avoidance pattern. The finding that there is still side-to-side asymmetry indicates that there is no complete reorganisation following the massive loss of input and output of the leg. It is possible that some reprogramming of the locomotor process occur. RELEVANCE: Gait and electromyographic analysis are essential for the quantitative assessments of the functional outcome in this type of surgery.     

The effects of light touch cue on gait initiation in patients with Parkinson's disease

IntroductionOne of the common impairments in patients with Parkinson's disease (PD) is disturbance of gait initiation. A light touch cue improves postural stability in patients with PD. Little is known about the effects of a light touch cue on gait initiation. This study investigated the effects of a light touch on gait initiation in patients with PD.MethodsThis study was a cross-sectional study design. Sixteen patients with PD (Hoehn & Yahr stage 2–3) participated in the study and were evaluated two gait conditions (no touch (NT) and light touch (LT) conditions). Gait initiation was divided into 5 events including event A, B, C, D, and E. Outcome measures included maximum center of pressure (COP) displacement and velocity in anteroposterior (AP) and mediolateral (ML) directions, and the first step time.ResultsParticipants with LT had greater COP displacement compared with the NT condition in all events of gait initiation except COP-AP displacement in event D. Additionally, the COP velocity in LT condition was faster than the NT condition in COP-ML velocity in event A, COP-AP velocity in event B, COP-AP velocity and COP-ML velocity in event C. Moreover, participants with LT presented significantly shorter the first step time than the NT condition.ConclusionsThese findings demonstrated that a light touch cue improved gait initiation in patients with PD by increased weight shifting to initial stance limb, increased postural stability of stance limb, increased velocity of weight transfer toward stance limb, and a shortened first step time.     

脑卒中患者偏瘫步态的时空及关节运动学参数分析

目的:探讨脑卒中患者偏瘫步态的时空及关节运动学参数,为临床康复评估和治疗提供客观依据.方法:脑卒中偏瘫患者和健康受试者各24例自愿参加本研究;其中脑卒中组男15例,女9例,脑出血5例,脑梗死19例,年龄(57.75±5.57)岁;对照组男12例,女12例,年龄(56.54±6.02)岁.应用Gait Watch步态分析系统评估步态的时空参数和下肢关节运动学参数.所有受试者由同一医师进行2次评估.结果:与对照组相比,脑卒中组的步频、步速显著降低,患侧步长显著缩短,步态周期和患侧支撑相均延长,患侧摆动相缩短.脑卒中组患侧髋关节的最大伸展角度明显受限(P=0.001),髋关节屈伸运动的平均角速度明显降低(P＜0.001),膝关节最大屈曲角度亦明显受限(P＜0.001),膝关节屈伸运动的平均角速度明显降低(P＜0.001),髋关节的最大屈曲角度和足偏角与对照组比较无明显差异.患者的步行能力显著下降.结论:Gait Watch步态分析系统可定量测量脑卒中偏瘫患者的步态特征和下肢的关节运动学参数,对于脑卒中偏瘫患者步行能力的评估具有较高敏感度.     

Knee joint moments during stair climbing of patients with anterior cruciate ligament deficiency

OBJECTIVE: To establish the gait adaptations of patients with anterior cruciate ligament deficiency during stair ascent. DESIGN: Joint kinematics and kinetics during stair climbing were measured in both knees of normal subjects and unilateral anterior cruciate ligament deficient patients. BACKGROUND: As there is limited research pertaining to activities other than level walking, the purpose of the current study was to elucidate the gait of patients with anterior cruciate ligament deficiency during stair climbing to determine the effects of the deficiency on knee joint motion and moments as compared with normal knee function. METHODS: A motion analysis system was used to measure and calculate kinematic and kinetic data for six normal subjects and nine patients with unilateral anterior cruciate ligament deficiency during stair ascent on a specially constructed staircase. Left and right leg data were analysed to reveal between-limb differences for each subject. RESULTS: Patients with anterior cruciate ligament deficiency displayed a significant (P < 0.05) reduction of up to 50% in peak knee flexion moments in their involved knee. In the present study where a step height of 15.5 cm was used, peak flexion moments in all subjects' limbs occurred at knee flexion angles of about 40 degrees during single limb support. CONCLUSION: The current study showed that most patients with an anterior cruciate deficient knee adapted their gait during stair ascent. RELEVANCE: As stair climbing is a common activity, its effect on gait is relevant to better understand appropriate treatment and management strategies of patients with anterior cruciate ligament deficient knees.     

Bilateral accommodations to anterior cruciate ligament deficiency and surgery

OBJECTIVE To determine bilateral lower extremity joint accommodations during gait in anterior cruciate ligament deficient subjects and uninjured controls. DESIGN: Gait testing of 10 chronic anterior cruciate ligament deficient subjects prior to and 3 months following reconstructive surgery, and 10 uninjured controls. BACKGROUND: It is possible that bilateral joint accommodations could occur as a result of anterior cruciate ligament injury and in response to surgical repair. Few studies have investigated bilateral joint accommodations to anterior cruciate ligament injury and there is little consistency in the reported results. METHODS: Bilateral lower extremity kinematic and kinetic data were collected from 12 walking trials and inverse dynamics calculations were made to estimate bilateral knee and hip joint angle, moment, and power patterns during the stance phase of gait. RESULTS: Control subjects exhibited asymmetrical hip but symmetrical knee joint moment and power patterns. In contrast, the anterior cruciate ligament deficient subjects exhibited symmetrical hip and asymmetrical knee joint moment and power patterns prior to and following reconstructive surgery. CONCLUSIONS: Gait asymmetry in healthy subjects should not be considered pathological. In addition, chronic anterior cruciate ligament injury results in joint specific, bilateral lower extremity accommodations in gait mechanics. These accommodations persist 3 months following surgical repair.