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.     

Asymmetry of gait initiation in patients with unilateral knee arthritis

OBJECTIVE: To identify how patients with knee arthritis modify their equilibrium and movement control strategies during gait initiation. DESIGN: Observational study. SETTING: University hospital movement analysis laboratory. PARTICIPANTS: Twelve patients with unilateral knee arthritis and 12 healthy control subjects. MAIN OUTCOME MEASURES: Durations of the phases of gait initiation (ie, postural, monopodal, and double-support phases), center-of-pressure displacements, ground reaction forces, pelvic velocity, step length, and knee range of motion were measured using a movement analysis system and force plates. RESULTS: Gait initiation was slower in patients than in controls no matter which leg was the supporting one. In patients, the durations of the postural and the monopodal phases were modified in an asymmetrical way according to the leg used as the supporting one. The postural phase was lengthened and the monopodal phase was shortened when the affected leg was the supporting one. Opposite effects were observed when the sound leg was supporting. Step length, knee range of motion, and maximal pelvic velocity were reduced in patients whatever the side of the supporting leg. CONCLUSION: Gait initiation is an asymmetrical process in unilateral knee arthritis patients, who develop adaptive posturomotor strategies that shorten the monopodal phase on the affected leg.     

Effects of a knee–ankle–foot orthosis on gait biomechanical characteristics of paretic and non-paretic limbs in hemiplegic patients with genu recurvatum

Background

A knee–ankle–foot orthosis may be prescribed for the prevention of genu recurvatum during the stance phase of gait. It allows also to limit abnormal plantarflexion during swing phase. The aim is to improve gait in hemiplegic patients and to prevent articular degeneration of the knee. However, the effects of knee–ankle–foot orthosis on both the paretic and non-paretic limbs during gait have not been evaluated. The aim of this study was to quantify biomechanical adaptations induced by wearing a knee–ankle–foot orthosis, on the paretic and non-paretic limbs of hemiplegic patients during gait.

Methods

Eleven hemiplegic patients with genu recurvatum performed two gait analyses (without and with the knee–ankle–foot orthosis). Spatio-temporal, kinematic and kinetic gait parameters of both lower limbs were quantified using an instrumented gait analysis system during the stance and swing phases of the gait cycle.

Findings

The knee–ankle–foot orthosis improved spatio-temporal gait parameters. During stance phase on the paretic side, knee hyperextension was reduced and ankle plantarflexion and hip flexion were increased. During swing phase, ankle dorsiflexion increased in the paretic limb and knee extension increased in the non-paretic limb. The paretic limb knee flexion moment also decreased.

Interpretation

Wearing a knee–ankle–foot orthosis improved gait parameters in hemiplegic patients with genu recurvatum. It increased gait velocity, by improving cadence, stride length and non-paretic step length. These spatiotemporal adaptations seem mainly due to the decrease in knee hyperextension during stance phase and to the increase in paretic limb ankle dorsiflexion during both phases of the gait cycle.     

Hemiplegic gait of stroke patients: the effect of using a cane.

OBJECTIVE: To assess the effects of cane use on the hemiplegic gait of stroke patients, focusing on the temporal, spatial, and kinematic variables. DESIGN: Case-control study comparing the effect of walking with and without a cane using a six-camera computerized motion analysis system. SETTING: Stroke clinic of a tertiary care hospital. PARTICIPANTS: Fifteen ambulatory stroke patients were analyzed, including 10 men and 5 women (mean age, 56.9 years; mean time since stroke, 9.8 weeks). Nine age-matched healthy elderly subjects were recruited as a control group. RESULTS: Stroke patients walking with a cane showed significantly increased stride period, stride length, and affected side step length, as well as decreased cadence and step width (p < .05) in comparison with those who walked without a cane. There were no significant differences in the gait phases and the five gait events of hemiplegic gait walking with or without a cane. Cane use thus may have more effect on spatial variables than on temporal variables. The affected-side kinematics of hemiplegic gait with a cane showed increased pelvic obliquity, hip abduction, and ankle eversion during terminal stance phase; increased hip extension, knee extension, and ankle plantar-flexion during preswing phase; and increased hip adduction, knee flexion, and ankle dorsiflexion during swing phase as compared with hemiplegic gait without a cane. A cane thus improved the hemiplegic gait by assisting the affected limb to smoothly shift the center of body mass toward the sound limb and to enhance push off during preswing phase. It also improved circumduction gait during swing phase. CONCLUSION: Stroke patients walking with a cane demonstrated more normal spatial variables and joint motion than did those without a cane.     

Asymmetries in dynamic plantar pressure distribution measurement in able-bodied gait: application to the study of the gait asymmetries in children with hemiplegic cerebral palsy]

OBJECTIVES: The aim of this study was to analyse, firstly, the plantar pressure distribution in healthy subjects in order to validate or invalidate the previous studies results on the asymmetrical profile of the stance phase. The studies of asymmetries was based on the identification of a propulsive foot and a loading foot from a concept introduced by Viel. Secondly, the approach was applied to the study of gait asymmetries in two children with hemiplegic cerebral plasy. MATERIAL AND METHOD: Thirty healthy control subjects and two hemiplegic children (H1 and H2) performed a walking test at self selected speed. The recordings of dynamic parameters were realized thanks to an in-shoe plantar pressure analysis system (Parotec, by Paromed Medizintechnik, GMBH, Germany). The pressure peaks were determined from the recording of pressures under eight footprint locations. A program calculated the sum of forces under the heel and determined the loading foot. By defect, the second foot is the propulsive foot. RESULTS: The asymmetrical profile of the human normal stance phase was validated. Under the heel, the pressure peaks lower by 28 % were noticed beneath the loading foot compared to the propulsive foot. Inversely, under the metatarsal heads and the hallux, the pressure peaks were greater by 32 % beneath the propulsive foot. For the two hemiplegic children, the plantar pressure profile equally highlighted significant differences between the unaffected and affected feet. The pressure peaks under the affected heel were respectively lower by 21 % and 97 % for H1 and H2. The loading function was found and associated to the affected limb. The propulsive function was not systematically found under the unaffected foot. DISCUSSION: The analysis of plantar pressure measurements during able-bodied gait showed differences between the two lower limbs. These dynamic asymmetries are the results of a natural functional organization of the supports differentiating a loading foot and a propulsive foot and corroborating the concept proposed by Viel. The hemiplegic gait also presented dynamic asymmetries partially agreement with a personalized functional logic of loading and propulsion. However, the asymmetrical profile can also result a gait self-optimization strategy compensating biomechanical, anatomical and physiological disorders linked to the cerebral deficiency.     

Temporal stride and force analysis of cane-assisted gait in people with hemiplegic stroke

OBJECTIVE: To understand the underlying biomechanics of temporal stride and force in people with hemiplegic stroke during cane-assisted walking. DESIGN: Three forceplates, 6 cameras, and an instrumented cane were integrated to analyze the cane-assisted gait of people with hemiplegic stroke. Temporal-stride parameters, and peak vertical, anterior (propulsive), posterior (braking), and lateral shear forces, as well as propulsive-breaking impulses were analyzed. SETTING: Chang Gung Memorial Hospital, Medical Center, Taiwan. PARTICIPANTS: Twenty people with hemiplegic stroke. MAIN OUTCOME MEASURES: Temporal-stride and force parameters. RESULTS: All patients walked at a relatively slow speed, ranging from 4.2 to 35.8cm/s. The triple and double support occupied most of the gait cycle (GC), whereas the single support occupied only 10% of GC. The applied vertical, propulsive, braking, and lateral shear forces on either foot and the cane were 89.7% to 97.6%, 2.2% to 4.8%, 2.9% to 3.9%, and 5.5% to 6.7% body weight (BW), respectively. Patients applied less than 25% BW of peak vertical forces on the cane. They applied greater peak propulsive forces and impulses on the sound foot, while applying greater peak braking forces and impulses on the affected foot and cane. CONCLUSIONS: The cane provided support and a braking function for people with hemiplegic stroke. People with stroke walking with cane assistance rely mostly on the sound limb for propulsion, while using the affected limb and cane for braking. Data provided could be useful in assessing the nature of cane assistance and in planning therapeutic strategies for people with stroke.     

Intrathecal baclofen in subjects with spastic hemiplegia: assessment of the antispastic effect during gait

OBJECTIVE: To determine whether leg muscle stiffness is measurably reduced after intrathecal baclofen (ITB) in subjects with spastic hemiplegia. DESIGN: Nonrandomized trial. SETTING: Inpatient multidisciplinary rehabilitation unit in France. PARTICIPANTS: Seven consecutive subjects with spastic hemiplegia having Ashworth Scale scores for their quadriceps and triceps greater than 2. INTERVENTION: Subjects were given ITB by lumbar puncture after a dose-selecting test period. MAIN OUTCOME MEASURES: Triceps and quadriceps Ashworth scores, gait analysis at preferred and maximal speed measured by a motion analysis system with 2 forceplates, and electromyographic recording of leg muscles before and 4 hours after ITB. The slopes of the moment-angle curves were measured on the hemiplegic side at the onset of ankle and knee flexion to assess muscle stiffness during walking. Pre- and post-ITB spatiotemporal, kinetic, and kinematic data were compared by using a nonparametric test (Wilcoxon signed-rank test). RESULTS: Ashworth scores of the quadriceps and triceps of all subjects decreased significantly after ITB. Maximal walking speed increased significantly, with a significant increase in stride length, but the preferred walking speed was unchanged. Minimal knee extension and maximal ankle flexion were the only kinematic data significantly different (increased) after ITB. The slope of the ankle moment-angle curve decreased significantly after ITB at preferred gait speed; it also decreased at maximal gait speed in all but 1 subject. Of the 4 available moment-angle curves, 3 showed decreased knee extensor muscle stiffness. The duration of the bursts of spastic muscles decreased after ITB. CONCLUSION: Acute ITB improved walking and reduced muscle stiffness at both the ankles and knees on the spastic hemiplegic side of our subjects. Electromyographic findings suggest that some of the post-ITB reduction in muscle stiffness might be attributed to decreased spasticity.     

A pilot study to investigate the combined use of Botulinum toxin type-a and ankle foot orthosis for the treatment of spastic foot in chronic hemiplegic patients

Background

Botulinum toxin is commonly used to treat spastic equinus foot. This treatment seems to improve gait in hemiplegic patients when used alone or combined with an ankle-foot orthosis. However, the nature and effects of this improvement have until now rarely been studied. The aim of this study was to quantify the impact of a Botulinum toxin injection in the triceps surae of hemiplegic patients with equinus foot, used either alone or in combination with an ankle-foot orthosis, on the kinematics and dynamics of the paretic lower limb, and to determine the advantage of combining an ankle-foot orthosis with this pharmacological treatment.

Methods

Patients were assessed using gait analysis to measure spatio-temporal, kinematic and dynamic parameters of the gait cycle before Botulinum toxin injection and then 3 and 6 weeks after injection. Eight chronic hemiplegics following central nervous system lesion were included.

Findings

Botulinum toxin injection led to an increase in velocity, peak ankle dorsiflexion during stance phase, and peak knee flexion during swing phase. It also resulted in an increased peak plantarflexion moment. Use of ankle-foot orthosis led to a specific increase in peak ankle dorsiflexion during swing phase and also increased peak plantarflexion moment.

Interpretation

The results indicate that combined Botulinum toxin injection of the triceps surae and wearing an ankle-foot orthosis is more effective than the use of Botulinum toxin only. Use of an ankle-foot orthosis increases ankle dorsiflexion during the swing phase and does not reduce the benefits gained by the use of Botulinum toxin in stance phase.     

Kinematic and kinetic analysis of the walking pattern in hemiplegic patients with foot-drop using a peroneal nerve stimulator

OBJECTIVE: To analyze the walking pattern in hemiplegic patients using a peroneal nerve stimulator to locate possible harmful mechanical effects on the musculo-skeletal system. DESIGN: Eight hemiplegic patients participated in the study. All patients had used a peroneal nerve stimulator regularly for more than two years and were able to perform unassisted walking. BACKGROUND: Peroneal nerve stimulators are widely applied for correction of foot-drop in hemiplegic patients. The stimulators do not induce normal dorsi-flexion, but a rather exaggerated dorsi-flexion and eventually eversion which might be harmful. METHODS: Three-dimensional kinematic and kinetic analyses of the walking patterns at self-selected speeds were performed with the patients walking without the stimulator and with the stimulator turned on. RESULTS: The walking speed increased on average from 0.77 (S.D., 0.83) to 0.84 (S.D., 0.11) (7.6%, P=0. 005) when the stimulator was used, however no uniform changes in the walking pattern and joint loads were observed. The total work (generation+absorption) produced by the affected leg (both with and without the peroneal nerve stimulator) was significantly lower (P=0. 005) than that of the contralateral leg. Deviations from normal power profiles were observed both on the affected and the contralateral side, and the walking efficiency was 57% lower compared to normal subjects. The estimated peak bone-on-bone forces corresponded to about 50% of what previously has been observed during normal walking at self-selected speed. CONCLUSIONS: The use of the peroneal nerve stimulator do not introduce any excessive and potential harmful mechanical loads. RELEVANCE: Applied correctly, the peroneal nerve stimulator can be used as an aid for foot-drop correction in hemiplegic patients without causing excessive wear on the joints in the lower extremity.     

脑卒中患者步行能力与下肢三维运动学及动力学相关性分析

目的:通过对脑卒中偏瘫患者下肢三维运动学和动力学的分析,寻找偏瘫患者步态特点,比较分析步行能力与运动学和动力学之间的关系,从运动力学角度探讨偏瘫患者异常步行的原因,寻找康复治疗中需解决的关键问题。方法:选择首次脑卒中后可以独立步行10m以上的右侧偏瘫患者20例为实验组,正常健康中老年人16例为对照组。采用Vicon和AMTOR6-7进行三维步态运动学和动力学检测和分析。结果:实验组与正常对照组比较,脑卒中患者与健康中老年人在步频、跨步时间、双腿支撑时间、步时、离地比率、步长、跨步长和步速同侧比较差异有显著性意义(P<0.05),患侧离地占步态周期百分比和健侧单腿支撑时间实验组与对照组比较差异有显著性意义(P<0.05)。矢状面上同侧髋关节伸展角度、膝关节屈曲角度和踝关节背伸及跖屈角度比较差异都有显著性意义(P<0.05)。同侧髋关节屈伸力矩、同侧膝关节伸直力矩和患侧踝关节背伸力矩实验组和对照组相比差异有显著性意义(P<0.05),步行能力(步速)与患侧髋关节伸展、健侧膝关节屈曲、双侧膝关节伸展、双侧踝关节背伸和跖屈角度相关,均有显著性意义(P<0.05);同时也和双侧髋关节屈伸、膝关节伸展和踝关节背伸力矩相关(P<0.01)。结论:①步长是脑卒中偏瘫患者步态异常的重要参考指数;②髋关节和膝关节伸展,踝关节背伸和跖屈是步态异常的重要表现;③下肢髋关节和膝关节屈伸肌群和踝关节背伸肌群的力量是影响步行能力的重要因素。     

Walking on uneven ground: How do patients with unilateral cerebral palsy adapt?

BackgroundChildren with cerebral palsy experience movement disorders that influence gait stability. It is likely that gait stability further decreases when walking on uneven compared to even ground. Therefore, the aim of this study was to investigate gait on uneven ground in children with unilateral cerebral palsy.MethodsTwenty children with unilateral cerebral palsy and twenty typically developing children performed a three-dimensional gait analysis when walking on even and uneven ground. Spatio-temporal parameters, full-body joint kinematics and centre of mass displacements were compared.FindingsOn uneven versus even ground, both groups showed decreased cadence, increased stance phase and double support time, increased toe clearance height, and increased knee and hip flexion during swing phase. Whereas only the typically developing children walked slower and had increased dorsiflexion and external foot progression during stance phase, only the patients showed increased stride width, increased elbow flexion (affected and non-affected side), and kept the centre of mass more medial when standing on the affected leg.InterpretationPatients and healthy children use similar adaptation mechanisms when walking on uneven ground. Both groups increased the toe clearance height by increasing knee and hip flexion during swing. However, whereas patients enlarge their base of support by increasing stride width, healthy children do so by increasing their external foot progression angle. Furthermore, patients seem to feel more insecure and hold their arms in a position to prepare for falls on uneven ground. They also do not compensate with their non-affected side for their affected side on uneven ground.     

Gait in hemiplegia: evaluation of clinical features with the Wisconsin Gait Scale.

OBJECTIVE: To assess the ability of the Wisconsin Gait Scale to evaluate qualitative features of changes in hemiplegic gait in post-stroke patients. DESIGN: A prospective observational study. SUBJECTS: Ten healthy subjects and 56 hemiplegic outpatients, more than 12 months post-stroke, consecutively admitted in a rehabilitation centre. METHODS: Patients were videotaped while walking at a comfortable speed. Quantitative and clinical gait parameters were derived from videotaped walking tasks at admission and at the end of a period of rehabilitation training. Qualitative features were assessed using the Wisconsin Gait Scale. Functional status was rated through the modified Barthel Index. RESULTS: After training, the median Wisconsin Gait Scale score improved significantly (28 vs 26.5; p = 0.003). In particular, "weight shift to paretic side" and patterns during the swing phase of the affected leg were improved. Gait velocity (0.3 vs 0.4 m/sec; p = 0.001) and stride length (77 vs 85 cm; p = 0.0002) increased significantly, whereas number of steps (25 vs 23; p = 0.004), stride period (2.5 vs 2.3 sec; p = 0.04), and stance period (2.1 vs 2 sec; p = 0.03) of the unaffected side were reduced. The Barthel Index score increased (71 vs 78; p = 0.005). CONCLUSION: The Wisconsin Gait Scale is a useful tool to rate qualitative gait alterations of post-stroke hemiplegic subjects and to assess changes over time during rehabilitation training. It may be used when a targeted and standardized characterization of hemiplegic gait is needed for tailoring rehabilitation and monitoring results.     

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.     

Dynamic resources used in ambulation by children with spastic hemiplegic cerebral palsy: relationship to kinematics, energetics, and asymmetries

BACKGROUND AND PURPOSE: The atypical walking pattern in children with spastic cerebral palsy is assumed to involve kinematic and morphological adaptations that allow them to move. The purpose of this study was to explore how the requirements of the task and the energy-generating and energy-conserving capabilities of children with cerebral palsy relate to kinematic and mechanical energy patterns of walking. SUBJECTS: Six children with hemiplegic cerebral palsy and a matched group of typically developing children participated in the study. METHODS: Kinematic data were collected at 5 different walking speeds. Vertical stiffness, mechanical energy parameters, and landing angle were measured during the stance phase. RESULTS: The affected side of the children with cerebral palsy showed greater vertical stiffness, a greater ratio of kinetic forward energy to potential energy, and a smaller landing angle when compared with those of the nonaffected lower extremity and with those of typically developing children. DISCUSSION AND CONCLUSION: Previous research has shown that children with cerebral palsy assumed a gait similar to an inverted pendulum on the nonaffected limb and a pogo stick on the affected limb. Our results indicate that asymmetries between lower extremities and differences from typically developing children in the landing angle of the lower extremity, vertical lower-extremity stiffness, and kinetic and potential energy profiles support the claim that walking patterns in children with spastic hemiplegic cerebral palsy emerge as a function of the resources available to them.     

三维步态在脑卒中足下垂患者下肢节段协调性分析的应用

目的:运用三维步态分析系统分析脑卒中偏瘫足下垂患者的下肢关节协调性.方法:选取脑卒中偏瘫足下垂患者15例作为观察组,配对设计选取15例健康者作为对照组一和对照组二.采集2组受试者行走过程中的时空参数和运动学参数,通过绘制仰角曲线图和步态环图进行协调性分析.结果:观察组偏瘫侧与非偏瘫侧比较,步频、支撑期百分比,髋、膝关节...     

Effects of a multichannel dynamic functional electrical stimulation system on hemiplegic gait and muscle forces

[Purpose] The purpose of the study was to design and implement a multichannel dynamic functional electrical stimulation system and investigate acute effects of functional electrical stimulation of the tibialis anterior and rectus femoris on ankle and knee sagittal-plane kinematics and related muscle forces of hemiplegic gait. [Subjects and Methods] A multichannel dynamic electrical stimulation system was developed with 8-channel low frequency current generators. Eight male hemiplegic patients were trained for 4 weeks with electric stimulation of the tibia anterior and rectus femoris muscles during walking, which was coupled with active contraction. Kinematic data were collected, and muscle forces of the tibialis anterior and rectus femoris of the affected limbs were analyzed using a musculoskelatal modeling approach before and after training. A paired sample t-test was used to detect the differences between before and after training. [Results] The step length of the affected limb significantly increased after the stimulation was applied. The maximum dorsiflexion angle and maximum knee flexion angle of the affected limb were both increased significantly during stimulation. The maximum muscle forces of both the tibia anterior and rectus femoris increased significantly during stimulation compared with before functional electrical stimulation was applied. [Conclusion] This study established a functional electrical stimulation strategy based on hemiplegic gait analysis and musculoskeletal modeling. The multichannel functional electrical stimulation system successfully corrected foot drop and altered circumduction hemiplegic gait pattern.Key words: Hemiplegia, Functional electrical stimulation, Gait     

Selective tibial neurotomy in the treatment of spastic equinovarus foot: a 2-year follow-up of three cases

OBJECTIVE: To objectively assess the decrease in spasticity and the improvement in gait after tibial nerve neurotomy performed to treat spastic equinovarus foot. DESIGN: Before-after trial with a 2-yr follow-up. Three hemiplegic patients with spastic equinovarus foot were treated with a selective peripheral neurotomy of the tibial motor nerve branches (soleus, lateral and medial gastrocnemius and tibialis posterior nerves). Evaluation included clinical assessment of spasticity (Ashworth scale), maximal Hoffmann reflex (H(max))/compound muscle action potential (M(max)) ratio measurement, gait analysis, and muscle stiffness evaluation performed before and 2 mos, 1 yr, and 2 yrs after the neurotomy. RESULTS: Spasticity, muscle stiffness, and H(max)/M(max) ratio decreased after neurotomy. The kinematic (ankle dorsal flexion and knee recurvatum) and kinetic variables (maximum ankle muscle moment and external work) of the gait were permanently improved after neurotomy. Interestingly, kinetic variables seemed to gradually improve with time after the neurotomy. CONCLUSION: Tibial neurotomy is an effective and durable treatment for spastic equinovarus foot.     

Motion of the center of gravity of the body in clinical evaluation of gait

The motion of the center of gravity during walking was analyzed in five hemiplegic subjects and eleven subjects affected by unilateral hip arthritis. In the hemiplegic subjects and 6 subjects with hip arthritis the transfer between kinetic and potential energy (with a passive pendular motion) was found to be 9-95% greater during the step performed on the affected limb ("pathological" step); as a consequence, the muscular work done during this step was 7-81% of the work done during the step performed on the second limb ("normal" step). Qualitatively similar gait anomalies were recorded in all hemiplegic subjects with hypertonus of the paretic limb: these subjects had to lift the spastic limb as a whole during the normal step, with the consequence that the center of gravity was lifted 0.6-3 cm more than during the pathological step. In contrast, various motor patterns were found in patients with hip arthritis. During the pathological step the center of gravity reached a height 0.5-3 cm greater in 7 subjects, 1 cm smaller in one subject, and about the same height reached during the normal step in 3 subjects. This was consistent with the various motor deficits caused by hip arthritis.     

Foot contact pattern analysis in hemiplegic stroke patients: an implication for neurologic status determination

OBJECTIVE: To investigate the feasibility of using a foot contact pattern to predict neurologic recovery and the effect of ambulation training in hemiplegic stroke patients. DESIGN: Case-comparison study. SETTING: Gait laboratory in a tertiary care center. PARTICIPANTS: Sixty-five functionally ambulant hemiplegic stroke patients, and 30 healthy subjects serving as the control group. INTERVENTIONS: Gait analyses were performed by using the conventional gait analysis system (6 cameras) and the portable Computer DynoGraphy (CDG) system.Main outcome measures Walking velocity, step length, and cadence were measured from the conventional gait analysis system. Cyclogram, gaitline, and ground reaction force (GRF) patterns were recorded with the CDG system. RESULTS: Velocity, cadence, and step length increased in higher Brunnstrom stages (P<.01). Negative correlation was noted between the Brunnstrom stages and the foot contact patterns (P<.01). Lower cyclogram, GRF, and gaitline patterns were expected in subjects with higher Brunnstrom stages. There were high prediction probabilities between cyclogram, gaitline, and GRF patterns. CONCLUSIONS: Foot contact pattern can be a simple and reliable indicator of hemiplegic gait in stroke patients. It is closely related to patient's neurologic status and is correlated with parameters obtained from conventional gait analysis systems. Pathologic presentations are noted in both the affected and unaffected limbs, suggesting that rehabilitation programs should be implemented on both sides.