Background Locomotor training (LT) to improve walking ability in people poststroke can be accomplished with therapist assistance as needed promote continuous stepping. Various robotic devices also have been developed that guide the lower limbs through a kinematically consistent gait pattern. It is unclear whether LT either or could kinematic coordination patterns during walking. Objective The purpose of this study was determine physical superior guided, symmetrical, robotic-assisted for...

Stiff-knee gait is defined as reduced knee flexion during the swing phase. It accompanied by frontal plane compensatory movements (eg, circumduction and hip hiking) typically thought to result from toe clearance. As such, we examined if assistance before foot-off would reduce exaggerated in people with stiff-knee after stroke.We used a robotic orthosis assist torque preswing phase 9 chronic stroke subjects on treadmill compared peak flexion, abduction, pelvic obliquity angles 5 nondisabled...

Clinical outcomes after robotic training are often not superior to conventional therapy. One key factor responsible for this is the use of control strategies that provide substantial guidance. This strategy only leads a reduction in volitional physical effort, but also interferes with motor relearning. We tested feasibility novel approach (active training) using powered gait orthosis (Lokomat) mitigating post-stroke impairments 52-year-old male stroke survivor. paradigm combined...

Robot-aided gait therapy offers a promising approach towards improving function in individuals with neurological disorders such as stroke or spinal cord injury. However, incorporation of appropriate control strategies is essential for actively engaging the patient therapeutic process. Although several algorithms (such assist-as-needed and error augmentation) have been proposed to improve active participation, we hypothesize that benefits these can be greatly enhanced if combined motor...

Non-invasive spinal stimulation has the potential to modulate excitability. This study explored modulatory capacity of sub-motor grid-based transcutaneous cord (tSCS) applied lumbar in neurologically intact participants. Our objective was examine effect grid on polysynaptic reflex pathways involving motoneurons and interneurons likely activated by Aβ/δ fiber-mediated cutaneous afferents. 

Approach. Stimulation delivered using two electrode montages, generating a net electric field...

Although stroke survivors often display abnormal joint torque patterns, studies of torque-coupling in the lower limb are lacking, despite their potential impact on gait abnormalities.Twenty-two chronic ambulating subjects and 11 age-matched control produced isometric hip torques frontal sagittal planes with hemiparetic leg (or randomly selected for group) postures that resemble stages gait. The involuntary knee were also recorded although no feedback or instructions given.In toe-off midswing...

This paper uses two symmetrical models, the passive compass-gait biped and a five-link 3-D biped, to computationally investigate cause function of gait asymmetry. We show that for range slope angles during 2-D walking mass distributions controlled walking, these models have asymmetric patterns between left right legs due phenomenon spontaneous symmetry-breaking. In both cases stable family gaits emerges from symmetric as total energy increases (e.g., fast speeds). The ground reaction forces...

Oral contraceptive pills, of all types, are used by approximately 151 million women worldwide; however, a clear understanding the concentrations endogenous and exogenous hormones across 28-day combination monophasic oral pill pack is not well described. In our study 14 female participants taking various we found significant fluctuations in hormone levels throughout cycle. Our analysis revealed significantly greater ethinyl estradiol on 20th 21st days active ingestion, compared with

The biomechanical characteristics of stiff knee gait following neurological injury include decreased flexion velocity at toe-off, which may be due to exaggerated quadriceps activity. neuromuscular mechanism underlying this abnormal activity is unclear, although hyperexcitable heteronymous reflexes a source impaired coordination. present study examines the contribution reflex from hip flexors on extensors stroke and its association with reduced swing-phase during walking. Twelve individuals...

The significant sex disparity in sports-related knee injuries may be due to underlying differences motor control. Although the development of sex-specific movement patterns is likely multifactorial, this study specifically focuses on potential modulatory role hormones.This aimed investigate muscle stretch reflex (MSR) across menstrual cycle. We hypothesized that MSR would fluctuate throughout cycle and lowest response correspond with peak concentrations estrogen.Nineteen healthy women age...

A mathematical model of the patello-femoral joint was introduced to investigate impact vastus medialis (longus, obliquus) forces on lateral contact force levels. In model, quadriceps were represented as five separate forces: lateralis, intermedius, rectus femoris, longus (VML), and obliquus (VMO). By varying relative generation ratios heads, estimated. We sought analytically determine range in VMO VML that cause a reduction or an increase forces, often pain. Our results indicated increased...

To determine if increased visual dependence can be quantified through its impact on automatic postural responses, we have measured the combined effect latencies and magnitudes of response kinematics transient optic flow in pitch plane with platform rotations translations.Six healthy (29-31 yrs) 4 visually sensitive (27-57 subjects stood a rotated (6 deg dorsiflexion at 30 deg/sec) or translated (5 cm 5 for 200 msec. Subjects either had eyes closed viewed an immersive, stereo, wide field view...

Involuntary responses to muscle stretch are often composed of a short-latency reflex (SLR) and more variable at longer latencies such as the medium-latency (MLR) long-latency (LLR). Although latency reflexes enhanced in upper limb during stabilization external loads, it remains unknown if they have similar role lower limb. This uncertainty results part from inconsistency with which been observed A review literature suggests that studies only observe SLRs used perturbations large...

We have previously shown that abduction angular perturbations applied to the knee consistently elicit reflex responses in joint musculature. Although a stabilizing role for such reflexes is widely proposed, there are as of yet no studies quantifying contribution these stiffness. In this study, we estimate mechanical contributions muscle contractions elicited by excitation periarticular tissue receptors medial-lateral hypothesize will significantly increase stiffness adduction/abduction...