Posts Tagged drop foot

[Abstract + References] Functional Electrical Stimulation for Gait Rehabilitation – Conference paper


Conditions that can lead to a full or partial motor function loss, such as stroke or multiple sclerosis, leave people with disabilities that may interfere severely with lower body movements, such as gait. Drop Foot (DF) is a gait disorder that results in a reduced ability or total inability to contract the Tibialis Anterior (TA) muscle, causing an inability to raise the foot during gait. One of the most effective methods to correct DF is Functional Electrical Stimulation (FES). FES is a technique used to reproduce the activation patterns of functional muscles, in order to create muscular contractions through electrical stimulation of the muscle’s nervous tissue.

FES has first been introduced in 1961. However, the available commercial FES systems still do not take into account the fact that the gait differs from subject to subject, depending on their physical conditionmuscular fatigue and rehabilitation stage. Therefore, they are unable to provide a personalized assistance to the user, delivering constant stimulation pulses that are only based on gait events. Consequently, they promote the early onset of fatigue and generate coarse movements. This dissertation aims to tackle the aforementioned issues by developing a FES system for personalized DF correction, tailored to each individual user’s needs through the use of a Neural Network (NN).

A Non-Linear Autoregressive Neural Network with Exogenous inputs (NARX Neural Network) was used to model the dynamics of the electrically stimulated TA muscle, in a novel approach that uses both the foot angle and the foot velocity. The model was combined with a Proportional Derivative controller to help compensate for any external disturbances. In order to create more natural movements, reference trajectories were obtained by recording the foot angle and velocity of healthy subjects walking at different speeds.

The system has been validated with a healthy subject walking at 3 different speeds on a treadmill: 1 km/h, 1.5 km/h and 2 km/h. It was able to track the desired trajectory for every speed, thus creating a more natural movement and effectively correcting DF gait.


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via Functional Electrical Stimulation for Gait Rehabilitation | SpringerLink

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[WEB SITE] Kinetic Research Flagship Ankle-Foot Orthosis

The Noodle is Kinetic Research’s flagship ankle-foot orthosis.  This patented technology creates a quick and simple solution for drop foot.   What makes this ultra-lightweight AFO special is its next generation of carbon fiber properties that allow it to maintain dynamic motion and energy return. The Noodle positions the foot correctly during the swing phase and dampens heel strike for a natural loading response, minimizing foot slap. The Noodle is available with either lateral or medial strut and is the least restrictive design for controlling drop foot.

For all off-the-shelf orders, Kinetic Research will precut the footplate to size at no additional cost. The Noodle is also available in build-to-order allowing you to adjust color, height, and flexibility.

Kinetic Research offers a variety of off-the-shelf and custom dynamic ankle braces each with its own character and effect to meet the individual needs of the user.

Kinetic Research


via Kinetic Research Flagship Ankle-Foot Orthosis | Lower Extremity Review Magazine

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[VIDEO] CVA/Drop Foot Patient Case Study & Casting – Arizona AFO – YouTube

Patient is a 48 year old male that suffered from a cerebrovascular accident which caused paralysis in the patients lower left extremity. This resulted the patient in having drop foot.

Patient was dispensed an Arizona Extended AFO which provided dorsi-flexion assist. For more information and other helpful videos, please visit us at

via CVA/Drop Foot Patient Case Study & Casting – Arizona AFO – YouTube

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[Abstract] Restoring mobility after stroke: first kinematic results from a pilot study with a hybrid drop foot stimulator (with References)



The objective was to obtain first insights into the kinematic and kinetic walking patterns resulting from an implanted functional electrical stimulation system in subjects with a drop foot caused by stroke.


Four subjects who experienced a stroke were chosen due to a comparatively long/short time after surgery and young/old at the stroke event were examined retrospectively with gait analysis. Kinematics and kinetics of normal walking were assessed in comparison with and without activated drop foot stimulation.


In general, an improvement regarding spatiotemporal parameters as a result of the stimulation could be observed. Walking speed was increased by 45 % and stride length by 22 % after a mean usage of 7 (2–14) months, whereas both younger subjects improved significantly more. Dorsiflexion increased in all subjects on average from 1.3° to 11.6° during initial contact as well as from 11.3° to 17.0° during mid-swing and therefore implies an advantage of around 5.5 inch foot clearance. Pathologic elements like knee hyperextension during loading response and mid-stance, leg circumduction during swing or the increased hip flexion of the contralateral leg during mid-stance could be in general adjusted with stimulation.


An implantable functional electrical stimulation system seems to be a promising treatment of drop feet following strokes. Further clinical investigations are necessary to confirm these first insights.

Source: Restoring mobility after stroke: first kinematic results from a pilot study with a hybrid drop foot stimulator | SpringerLink

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[VIDEO] Home remedies for my drop foot? – YouTube

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[Abstract] Thesis (Doctoral). A quantitative and qualitative exploration of changes in walking post-stroke and the impact of functional electrical stimulation for correction of dropped foot.


The research presented in this thesis explores changes in walking following a stroke, empirically at a group level and from the perspective of the individual. Walking does not appear to have been previously been systematically explored from the perspective of the individual stroke survivor. In the first phase of this research, quantitative methods were used to investigate existing gait rehabilitation interventions applied in a novel population. Problems with ‘dropped foot’ post-stroke are common and can result in trips, falls and restricted mobility. Electrical stimulation of the common peroneal nerve produces dorsiflexion and eversion to correct dropped foot and is associated with improved motor control and walking post-stroke, however most research studies have recruited people with chronic stroke to reduce sample variability. People who are less than six months post-stroke may gain added benefit from electrical stimulation as poor walking patterns may not yet have become habitual and the potential for motor recovery due to cortical reorganisation is greatest. A pilot parallel group partially single blinded randomised controlled clinical trial (n=20) identified statistically significant within group differences in mobility after the intervention period in both groups (maintained during follow-up). No statistically significant between group differences were observed apart from gait quality, which was slightly better in the intervention group. Participants in the intervention group also walked faster when stimulation was used than without it. The protocol was feasible and 144 participants per group would produce an adequately powered definitive study. Participants in the pilot clinical trial spoke about valued personal aspects of walking but these were not fully captured by the outcome measures and are not reflected in the published literature. To systematically explore changes in walking post-stroke in depth interviews with a subgroup of the original participants were undertaken using an interpretative phenomenological approach (n=4). The participants gave examples of post-stroke walking related changes in their self-perception, roles and their embodied experience of walking that are rarely mentioned in the rehabilitation literature, apart from in personal accounts written by people living with chronic illness. They spoke about walking within the context of activities that they identified as personally important. These participants valued being able to walk distances at a reasonable speed, being independent, safe and confident. They said that they missed their pre-stroke spontaneity, freedom, agility and their lost automatic body movement, which are not usually assessed in stroke rehabilitation research or reflected in published research. Areas for further work have been identified.

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Source: A quantitative and qualitative exploration of changes in walking post-stroke and the impact of functional electrical stimulation for correction of dropped foot – ePrints Soton

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[Abstract] Evaluation of the Efficacy and Robustness of a Second Generation Implantable Stimulator in a Patient With Hemiplegia During 20 Years of Functional Electrical Stimulation of the Common Peroneal Nerve.

Artificial OrgansAbstract

We evaluated the efficacy and robustness of a second generation implantable stimulator for correcting drop foot (DF) in a patient with left-sided hemiplegia over 20 years of functional electrical stimulation (FES) of the common peroneal nerve (CPN). Dorsal flexion and eversion of the affected foot was partially restored by FES of the superficial region of the CPN innervating mostly the tibialis anterior (TA) and partly peroneus longus (PL) and peroneus brevis (PB) muscles. The reasons for implant failure during the long-term follow-up assessment were analyzed and resolving procedures were identified. The stimulator had an average failure rate of once every three years, due to repetitive mechanical load on the lead wires of its internal and/or external unit, and had to be serviced once per year to replace the heel switch integrated into the shoe sole. FES-associated mechanical trauma to the CPN elicited a thickening of the connective tissue around the CPN and a slightly compromised conduction velocity of the CPN. FES of the CPN, with the second generation implantable stimulator, improved gait parameters of the affected leg during the 20 years period. Long-term, daily FES enables a functional and reliable recruitment of nerve fibers, thus providing a sufficient dorsal flexion and optimal eversion of the affected foot to sustain unassisted, almost normal gait. Therefore, the presented implant is suitable for very long-term FES of the CPN.

Source: Evaluation of the Efficacy and Robustness of a Second Generation Implantable Stimulator in a Patient With Hemiplegia During 20 Years of Functional Electrical Stimulation of the Common Peroneal Nerve – Pečlin – 2016 – Artificial Organs – Wiley Online Library

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[WEB SITE] Apex Spring Collection | Lower Extremity Review Magazine

Apex introduces its Spring Collection, designed to offer consummate style, superior comfort, and expert construction. Each pair is crafted with high-quality

Source: Apex Spring Collection | Lower Extremity Review Magazine

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[ARTICLE] Effectiveness of Single Functional Electrical Stimulation in Neurological Patients with Ankle-Foot Orthoses – Full Text PDF


Background: Drop foot is a distal deficiency common in patients with central nervous system diseases that makes clearance difficult during swing phase, contributes to inefficient gait compensations, contributes to increase incidence of falls and energy expenditure. Aim of this study is to evaluate the effectiveness of a single application of functional electrical stimulation compared with ankle-foot orthoses in patients with drop foot.

Methods: Patients enrolled were unable to walk and to perform test without ankle-foot orthoses. They were evaluated by 10-meters walk test, obstacles test, up-and-down stair test, six-minute walk test and gait analysis with inertial sensors. All tests were performed with ankle-foot orthoses and with no ankle-foot orthoses and application of single functional electrical stimulation.

Results: Thirteen patients (8 males and 5 females) were recruited for this study out of 41 potential subjects. Data collected were processed by Student’s t test and by Wilcoxon test for paired observations and by Student’s t test and Mann-Whitney test for independent samples. P ≤ 0.05 were considered significant. For each test suitable effect sizes (Cohen’s d, and Pearson’s r) were calculated. Analysis of results with ankle-foot orthoses and with no anklefoot orthoses and application of single functional electrical stimulation showed no statistically significant difference in all test.

Conclusions: The use of single functional electrical stimulation showed same effects of ankle-foot orthoses on walking capacity and motor performance in chronic neurological diseases. More studies would be required to assess the long term effectiveness of functional electrical stimulation and to evaluate if its application in acute-phase may be used in association with traditional treatment.

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[ARTICLE] New therapeutic option for drop foot with the ActiGait peroneal nerve stimulator – A technical note


  • -Drop foot due to a peripheral nerve injury should be excluded before surgery
  • -Exact planning of implants’ position ensures a comfortable handling of the device
  • -Strainless implantation of the cable to avoid nerve injury due to tug at the nerve


A drop foot occurs in up to 20% of stroke patients and leads to an increased risk of falls. Until recently, only a foot orthosis or surface stimulation were able to improve the gait of these patients. Recent studies have shown that direct peroneal nerve stimulation with an implantable four-channel peroneal nerve stimulator (ActiGait) allows independent electrode adjustment and leads to better functional results and an improved quality of life. The application of this therapeutic option is restricted to patients with a drop foot attributable to a lesion of the first motor neuron caused by stroke, multiple sclerosis or tumors.In this paper, we present the first technical note with possible pitfalls of the surgical procedure and the perioperative care after implantation of ActiGait drop foot stimulators in 50 patients.

via New therapeutic option for drop foot with the ActiGait peroneal nerve stimulator – A technical note – World Neurosurgery.

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