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11.
M. Cioni I. Iero G. Tornatore A. Cocilovo A. Belfiore R. Ferri 《Neurological sciences》2007,28(2):100-103
Abstract We describe kinematics, kinetics and electromyographic patterns of a patient with spinal myoclonus of the left lower limb,
during walking. Gait analysis was performed when the patient was OFF and ON his treatment with antiepileptic drugs. When OFF,
we mainly observed clonic bursts and out-of-phase activations of m. tibialis anterior and m. rectus femoris, with increased
hip flexion, reduction of knee flexion during swing and excessive ankle dorsal flexion. Furthermore, large oscillations of
knee moment of force and power during stance phase were also observed. These abnormal patterns markedly recovered when ON
drugs. 相似文献
12.
Max J. Kurz Konstantinos Pothakos Sakeena Jamaluddin Melissa Scott-Pandorf Chris Arellano Yuen-Sum Lau 《Neuroscience letters》2007
The purpose of this investigation was to determine if a chronic Parkinson's disease mouse model will display less certainty in its gait pattern due to basal ganglia dysfunction. A chronic Parkinson's disease mouse model was induced by injecting male C57/BL mice with 10 doses of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (25 mg/kg) (MPTP) and probenecid (250 mg/kg) (P) over 5 weeks. This chronic model produces a severe and persistent loss of nigrostriatal neurons resulting in dopamine depletion and locomotor impairment. The control mice were treated with probenecid alone. Fifteen weeks after the last MPTP/P treatment, the mice were videotaped in the sagittal plane with a digital camera (60 Hz) as they ran on a motorized treadmill at a speed of 10 m/min. The indices of gait and gait variability were calculated. Stride length was significantly (p = 0.016) more variable in the chronic MPTP/P mice. Additionally, the chronic MPTP/P mice had a statistically less certain gait pattern when compared to the control mice (p = 0.02). These results suggest that variability in the gait pattern can be used to evaluate changes in neural function. Additionally, our results imply that disorder of the basal ganglia results in less certainty in modulating the descending motor command that controls the gait pattern. 相似文献
13.
Salman Nazary-Moghadam Mahyar Salavati Ali Esteki Behnam Akhbari Sohrab Keyhani Afsaneh Zeinalzadeh 《The Knee》2019,26(1):88-96
Background
Several investigations have studied gait variability of individuals with anterior cruciate ligament (ACL) deficiency; however, the effect of dual-tasking on the gait variability of these individuals remained unclear. The aim of the present study was to determine the effect of gait speed and dual-tasking on knee flexion–extension variability in subjects with and without ACL deficiency.Methods
The knee flexion–extension Lyapunov exponent (LyE) was measured in 22 ACL-deficient (Mean±SD) (25.95?±?4.69?years) and 22 healthy subjects (24.18?±?3.32?years). They walked at three levels of gait speed in isolation or concurrently with a cognitive task.Results
Repeated-measure analyses of variance (ANOVAs) demonstrated that the interaction of group by gait speed was statistically significant. As the gait speed increased from low to high, the knee flexion–extension LyE significantly decreased for the subjects with ACL deficiency (effect size: 0.57, P?=?0.01). The interaction of group by cognitive load was not statistically significant (P?=?0.07). In addition, the ACL-deficient subjects had statistically slower reaction times than healthy subjects during the dual-task compared with the single-task condition.Conclusions
The ACL-deficient and healthy individuals had a tendency to maintain safe gait. It seems that the ACL-deficient subjects sacrificed the cognitive task more than the healthy individuals to pay more attention toward gait. Additionally, it seems that the gait speed was more challenging than cognitive load on the stride-to-stride variability in the individuals with ACL deficiency. 相似文献14.
Quaternion-based strap-down integration method for applications of inertial sensing to gait analysis
Sabatini AM 《Medical & biological engineering & computing》2005,43(1):94-101
The proposed strap-down integration method exploits the cyclical nature of human gait: during the gait swing phase, the quaternion-based
attitude representation is integrated using a gyroscope from initial conditions that are determined during stance by an accelerometer.
Positioning requires double time integration of the gravity-compensated accelerometer signals during swing. An interpolation
technique applied to attitude quaternions was developed to improve the accuracy of orientation and positioning estimates by
accounting for the effect of sensor bias and scale factor drifts. A simulation environment was developed for the analysis
and testing of the proposed algorithm on a synthetic movement trajectory. The aim was to define the true attitude and positioning
used in the computation of estimation errors. By thermal modelling, the changes of bias and scale factor of the inertial sensors,
calibrated at a single reference temperature, were analysed over a range of ±10°C, for measurement noise standard deviations
up to σg = 2.5° s−1 (gyroscope) and σa = 0.05 m s−1 (accelerometer). The compensation technique reduced the maximum root mean square errors (RMSEs) to: RMSEθ=14.6° (orientation) and RMSEd=17.7 cm (positioning) for an integration interval of one gait cycle (an improvement of 3° and 7 cm); RMSEθ=14.8° and RMSEd=30.0 cm for an integration interval of two gait cycles (an improvement of 11° and 262 cm). 相似文献
15.
《The Foot》2021
ObjectiveThis study was conducted to investigate the effects of restriction of forefoot rocker (FFR) functions by immobilisation of unilateral metatarsophalangeal joints (MPJs) on kinematic and kinetic factors during walking.MethodsEighteen healthy young adults participated in this study. To immobilise the MPJs of the right leg, an aluminium sole plate (AS) was fixed on the sole of the foot. Kinematic and kinetic data were collected while each subject walked at a comfortable speed with the AS and without.ResultsIn the AS condition, the walking speed and contralateral step length were significantly decreased, and an asymmetrical centre of mass (COM) movement was observed. The range of plantarflexion motion and positive work by the ankle joint were decreased markedly during the late stance of the AS limb. In contrast, maximum hip and knee flexion angles in the swing phase of the AS limb and positive work by the bilateral hip joints over the gait cycle were increased.ConclusionsThe results suggested that MPJ immobilisation may result in marked motion limitation of ankle plantarflexion and inhibition of push-off by the ankle joint despite no restrictions on the ankle joint. These changes may interfere with gait speed and a smooth and symmetrical COM shift during walking. 相似文献
16.
Andrea Franz Daniel Herz Jens Raabe Ulrike Seeberger Christine Bollmann 《Foot and Ankle Surgery》2021,27(4):389-394
BackgroundFlatfoot is a frequent skeletal deformity in childhood that can be minimally invasively treated by arthroereisis. Question: Does the motion of juvenile flexible flatfoot normalize after arthroereisis?MethodPedographic measurements were obtained from 39 patients preoperatively, six months postoperatively and compared to a healthy group. The footprints were divided into 8 areas. The selected parameters were: contact area and force-time-integral.ResultsAfter surgery, a load shift from the medial to the lateral areas was detected under the midfoot and forefoot. The force-time-integral under the hallux normalized. However, under the lateral midfoot, the postoperative force-time-integral was significantly higher than in the control group.SignificanceThe study shows that arthroereisis is able to correct the medially displaced load distribution of juvenile flexible flatfoot. However, further investigations are required to find out if the higher punctual loading under the lateral midfoot may cause problems in the long term. 相似文献
17.
IntroductionStroke is the leading cause of non-traumatic disability in adults, with balance and gait disturbances representing the main limitations of body functions. Dance therapy (DT) has shown positive effects in older adults and in patients with neurological pathologies. This systematic review aims to examine the feasibility, acceptability and effects of DT in stroke rehabilitation, specifically on functional gains of gait and balance.MethodsA systematic search was carried out for articles published in the MEDLINE, PEDro, Web of Science, Scopus and CINHAL in February 2021 and updated in April 2021. Results: Eight studies were included (2 clinical cases, 5 case series and 1 randomized controlled trial), 7 of them in patients with chronic stroke and only 1 in subacute stroke phase. The most widely used dance modality was tango and ballet, with sessions ranging from 30 to 110 min. DT seems to show positive effects on post-stroke body functions and activities such as gait and balance. Reported dropout rates are inconsistent, no adverse effects were reported, and participant satisfaction was high.ConclusionGiven the heterogeneity and uneven quality of the included studies, strong conclusions cannot be put forward on the effectiveness of DT in post-stroke body function and activities. Nevertheless, DT seems to be safe and acceptable therapy for patients, and no adverse effects have been reported. More studies with a high level of evidence and feasibility are needed to determine the patient profile, the characteristics of the intervention, the participation rate and the role of the rehabilitation professional most likely to generate optimal benefit. 相似文献
18.
A comparison of gait initiation and termination methods for obtaining plantar foot pressures 总被引:2,自引:0,他引:2
The midgait protocol is the most commonly used method to collect pressure platform data. Spatial limitations, however, frequently render this technique unsuitable. Alternative gait protocols have focused on gait initiation procedures in obtaining data. The current study investigated whether a commonly cited two-step gait initiation protocol, or a two-step gait termination protocol produced pressure data more representative of the criterion, midgait method. A pressure platform was used to collect data for 25 asymptomatic subjects using the midgait, two-step gait initiation and two-step gait termination walking protocols. The contact duration, percentage contact duration, peak pressure, peak force, pressure–time integral and force–time integral were calculated for seven sites within the foot. Multivariate analysis of variance with repeated measures identified significant protocol by site interactions for all variables except the force-time integral. The gait initiation protocol, although having minimal effect on peak pressures beneath the forefoot, markedly altered the relative timing parameters of the foot. In contrast, the gait termination protocol had minimal effect on temporal parameters, but resulted in a reduction in pressures beneath the forefoot. Abbreviated gait protocols are often employed in plantar pressure studies. This study suggests that the choice between a gait initiation and termination protocol is largely dependent on the gait parameter of interest. 相似文献
19.
Whittle MW 《Gait & posture》1999,10(3):870-275
At the end of the swing phase of gait, the moving foot generates a transient force, due to the exchange of momentum as it contacts the ground. This review article examines the transient, which is known as the heelstrike in walking and the footstrike in running. The resulting ‘shock wave’, which passes up the limb, may produce damage, leading to degenerative joint disease and a variety of other pathologies. Protection against transient forces is provided by limb positioning at initial contact, by the anatomical heel pad, by materials used in shoe construction and by the use of viscoelastic shoe inserts. 相似文献
20.
Relationship between lower limb dynamics and knee joint pain 总被引:6,自引:0,他引:6
E L Radin K H Yang C Riegger V L Kish J J O'Connor 《Journal of orthopaedic research》1991,9(3):398-405
To test the hypothesis that appropriate and timely neuromuscular control of limb motions plays an important role in the preservation of joint health, we kinematically and kinetically examined the behavior of the legs of young adult subjects at heel strike during natural walking. We compared a group of 18 volunteers, who, we presumed, were preosteoarthrotic because of mild, intermittent, activity-related knee joint pain, with 14 age-matched asymptomatic normal subjects. The two groups of subjects exhibited similar gait patterns with equivalent cadences, walking speeds, terminal stance phase knee flexion, maximum (peak) swing angular velocity, and overall shape of the vertical ground reaction. However, our instrumentation detected statistically significant differences between the two groups within a few milliseconds of heel strike. In the knee pain group, the heel hit the floor with a stronger impact in this brief interval. Just before heel strike, there was a faster downward velocity of the ankle with a larger angular velocity of the shank. The follow-through of the leg immediately after heel strike was more violent with larger peak axial and angular accelerations of the leg echoed by a more rapid rise of the ground reaction force. This sequence of events represents repetitive impulsive loading, which consistently provoked osteoarthrosis in animal experiments. We refer to this micro-incoordination of neuromuscular control not visible to the naked eye as "microklutziness." 相似文献