Evaluation of a dynamic ankle foot orthosis in hemiplegic gait: A case report

Carbon fiber ankle-foot orthoses in impaired populations: A systematic review

BACKGROUND

Carbon fiber is increasingly being used in ankle-foot orthoses (AFOs). Orthotic devices and carbon fiber-containing devices have been shown to reduce pain and improve function in multiple patient populations. Although the number of publications and interest in carbon fiber AFOs is growing, a systematic evaluation of their effects is lacking.

OBJECTIVES

To characterize the effects of carbon fiber AFOs in impaired individuals.

STUDY DESIGN

Qualitative systematic review.

METHODS

Systematic searches in PubMed, Embase, CINAHL, and Cochrane Library were completed in July 2020. The results were deduplicated, screened, and assessed for quality by independent reviewers. Articles were excluded if they had nonhuman subjects, only healthy subjects, or included active control systems, motors, or other power sources.

RESULTS

Seventy-eight articles were included in the qualitative synthesis. Most articles were of low to moderate methodological quality. Five commonly used devices were identified: the Intrepid Dynamic Exoskeletal Orthosis, ToeOff, WalkOn, Neuro Swing, and Chignon. The devices have unique designs and are associated with specific populations. The Intrepid Dynamic Exoskeletal Orthosis was used in individuals with lower-limb trauma, the Neuro Swing and ToeOff in individuals with neurological disorders, the Chignon in individuals with hemiplegia and stroke, and the WalkOn in people with hemiplegia and cerebral palsy. Each device produced favorable outcomes in their respective populations of interest, such as increased walking speed, reduced pain, or improved balance.

CONCLUSIONS

The mechanical characteristics and designs of carbon fiber AFOs improve outcomes in the populations in which they are most studied. Future literature should diligently report patient population, device used, and fitting procedures.

Using 3-Dimensional Motion Analysis to Optimize Treatment Planning for a Patient With Dropfoot: Case Report

OBJECTIVE

This study demonstrated the use of computerized motion analysis to assist in evidence-based clinical decision-making.

CASE DESCRIPTION

A 15-year-old girl who had right hemiparesis after a stroke was referred for 3-dimensional computerized motion analysis to determine the effect of 3 devices intended to control her dropfoot and to assist in developing a treatment plan. Four conditions were tested and compared: barefoot, lateral support ankle brace, functional electrical stimulation (FES) device, and dropfoot cuff.

RESULTS

Kinematics showed the right ankle had significant dropfoot during swing phase (32.7 degrees of plantarflexion at terminal swing) in barefoot. The lateral support ankle brace, FES device, and dropfoot cuff reduced terminal swing plantarflexion to 27.2 degrees, 17.6 degrees, and 15.3 degrees, respectively, though ankle kinematics remained abnormal because of inadequate dorsiflexion. Improvements in gait variable score with FES (-8.2 degrees) or dropfoot cuff (-8.7 degrees) were significantly more than that with the lateral support brace (-2.2 degrees), and the difference in gait variable score between FES and dropfoot cuff was insignificant. Compared with the barefoot condition, the lateral support brace condition did not show a clinically significant difference in gait profile score; however, the gait profile scores of both FES and dropfoot cuff conditions showed clinically significant improvement (-1.7 degrees and -2.1 degrees, respectively).

CONCLUSION

Objective data delineated subtle changes among 3 devices and led to the recommendation to discontinue the lateral support ankle brace, continue using her night ankle-foot orthosis and FES device, with the dropfoot cuff as a backup when she feels leg fatigue or skin irritation, and consider serial casting or surgical calf lengthening.

IMPACT

Computerized motion analysis provides quantitative evaluation of subtle differences in the effect of braces with different designs, which are hard for the human eye to discern. The objective data inform and validate treatment decision-making. The recommendations were made as a result of evidence-based practice.

Kinematic on Ankle and Knee Joint of Post-Stroke Elderly Patients by Wearing Newly Elastic Band-Type Ankle-Foot Orthosis in Gait

Purpose

The post-stroke elderly was increased caused by increasing stroke and advanced medical. However, ankle–foot orthoses (AFOs) can be uncomfortable for hemiplegic patients; therefore, the usability is not good. In this study, we analyzed ankle and knee joint angles in post-stroke elderly patients to assess the functional effectiveness (specifically prevention of back knee and drop-foot) of a new elastic band-type AFO (New Product: NP) during gait.

Patients and methods

Nine elderly post-stroke patients (eight males, one female; 55.7±8.4 years; 165.8±9.2 cm; 68.8±11.5 kg; five with right hemiplegia, four with left hemiplegia; onset period: 6.6 years) were selected for participation in this study. We captured gait motion using 12 cameras (MX-T20, Vicon, Inc., Oxford, UK) under three different conditions [wearing nothing (WI), using existing ordinary AFOs made from hard plastic material (EP), and using NP]. The angle variation and maximum–minimum angle of the lower body joints were analyzed during dorsi-plantar flexion of the ankle joint and flexion–extension of knee joint. A one-way ANOVA test for multiple comparisons was performed, followed by a Tukey’s b test to identify statistical significance, which was set at 0.005.

Results

Regarding the ankle joint, the maximum plantar flexion (drop-foot) value decreased with the NP, and the maximum dorsiflexion value increased. Regarding the knee joint, the maximum extension (back knee) value decreased, and the maximum flexion value increased (p < 0.005).

Conclusion

Using analysis of the kinematics of the ankles and knees during walking, this research confirmed the effectiveness of the NP, an elastic band-type AFO, for use in ordinary post-stroke elderly patients.

Wearable tubing assistive walking device immediately enhances gait parameters in subjects with stroke: A randomized controlled study

BACKGROUND

Stroke patients develop compensatory movements due to limitations of ankle dorsiflexion and knee flexion. To solve the limitations, there are many adjustable walking assistive devices such as robotic devices, ankle-foot orthoses, and functional electric stimulation in rehabilitation session. However, these assistive devices have some disadvantages, including expense and discomforts. Therefore, the development of a new assistive device for stroke patients is needed to assist ankle dorsiflexion and knee flexion.

OBJECTIVE

This study investigated the effects of a wearable tubing assistive walking device (WTAWD) on gait parameters (gait speed, cadence, and step length and stride length on affected and less affected sides) in patients with stroke.

METHODS

Gait parameters were measured using the GAITRite system. One-way repeated measures analysis of variance was used to determine gait differences under three conditions (WTAWD, barefoot, and conventional elastic band orthosis).

RESULTS

Gait speed, cadence, and step length and stride length on both affected and less affected sides were significantly greater with WTAWD, compared to barefoot and conventional elastic band orthosis conditions.

CONCLUSION

WTAWD could be effective for patients with stroke.

Immediate-term effects of use of an ankle-foot orthosis with an oil damper on the gait of stroke patients when walking without the device

BACKGROUND

An ankle-foot orthosis using an oil damper is designed to enable natural movement of the ankle joint. Wearing an ankle-foot orthosis using an oil damper has been demonstrated to assist the first rocker in stroke patients, but its effect on their gait when not wearing it is unclear.

OBJECTIVES

To determine the effect of use of ankle-foot orthosis using an oil damper on the gait of stroke patients with hemiparesis when not wearing the ankle-foot orthosis.

STUDY DESIGN

Crossover study.

METHODS

The gait of eight stroke patients in the chronic phase when not wearing an ankle-foot orthosis was measured, using a three-dimensional motion analysis system, before using the ankle-foot orthosis using an oil damper and then without and with using the ankle-foot orthosis using an oil damper after 3 weeks of use. Differences in gait were compared between the three measurement conditions.

RESULTS

Use of ankle-foot orthosis using an oil damper significantly decreased preswing time and significantly increased the positive ankle joint power in stance when not wearing the ankle-foot orthosis using an oil damper.

CONCLUSIONS

These changes indicate the promising therapeutic effects of ankle-foot orthosis using an oil damper use and suggest the ankle-foot orthosis using an oil damper's potential as a therapeutic device.

CLINICAL RELEVANCE

After 3 weeks of use of an ankle-foot orthosis using an oil damper, which assists the first rocker, the gait of stroke patients in the chronic phase when not wearing the ankle-foot orthosis using an oil damper was improved. Preswing time was significantly decreased and positive ankle joint power was significantly increased. The ankle-foot orthosis using an oil damper, which assists the first rocker function with natural movement of the ankle joint during gait, has the potential to improve the gait of stroke patients after immediate-term use.

Measuring ambulation in adults with central neurologic disorders

This review discusses challenges faced by clinicians and researchers when measuring ambulation in individuals with central neurologic disorders within 3 distinct environments: clinical, laboratory, and community. Even the most robust measure of ambulation is affected by the environment in which it is implemented and by the clinical or research question and the specificity of the hypothesis being investigated. The ability to accurately measure ambulation (one of the most important metrics used to show transition into a community environment) is essential to measure treatment effectiveness and rehabilitation outcomes in populations with central neurologic disorders.

Effects of ankle foot orthosis in stiff knee gait in adults with hemiplegia

Stroke survivors present a less efficient gait compared to healthy subjects due to abnormal knee flexion during the swing phase of gait, associated with spasticity of the rectus femoris muscle and overactivity of the ankle plantarflexors. It is relevant to understand the effect of the ankle foot orthosis (AFO) on gait in individuals with plantarflexor spasticity. The aim of this study was to compare the knee kinematics with an AFO/footwear combination and barefoot in post-stroke subjects with plantarflexor spasticity. Ten subjects with chronic hemiplegia were measured. Two kinematic variables were assessed during the swing phase of the paretic limb: knee flexion angle at toeoff and peak knee flexion angle. We also analyzed gait speed and step length of the non-paretic limb. All variables were obtained with and without the orthosis. Kinematic data were acquired using a motion capture system (ELITE). Subjects wearing an AFO showed significant improvements in gait speed (0.62 m/s (0.08 SD) vs. 0.47 m/s (0.13 SD) (p=0.007)), step length of the non-paretic limb (42 cm (5.9 SD) vs. 33.5 cm (6.6 SD) (p=0.005)) and peak knee flexion angle during the swing phase: 30.7° (14.1° SD) vs. 26.3° (11.7° SD) p=0.005. No significant differences were obtained in the knee flexion angle at toeoff between no AFO and AFO conditions. We described benefits with AFO/footwear use in the kinematics of the knee, the step length of the non-paretic limb, and the gait velocity in hemiplegic subjects after mild to moderate stroke. We conclude that the use of an AFO can improve the gait pattern and increase velocity in these subjects.

An exoskeleton using controlled energy storage and release to aid ankle propulsion

Symmetric ankle propulsion is the cornerstone of efficient human walking. The ankle plantar flexors provide the majority of the mechanical work for the step-to-step transition and much of this work is delivered via elastic recoil from the Achilles' tendon - making it highly efficient. Even though the plantar flexors play a central role in propulsion, body-weight support and swing initiation during walking, very few assistive devices have focused on aiding ankle plantarflexion. Our goal was to develop a portable ankle exoskeleton taking inspiration from the passive elastic mechanisms at play in the human triceps surae-Achilles' tendon complex during walking. The challenge was to use parallel springs to provide ankle joint mechanical assistance during stance phase but allow free ankle rotation during swing phase. To do this we developed a novel `smart-clutch' that can engage and disengage a parallel spring based only on ankle kinematic state. The system is purely passive - containing no motors, electronics or external power supply. This `energy-neutral' ankle exoskeleton could be used to restore symmetry and reduce metabolic energy expenditure of walking in populations with weak ankle plantar flexors (e.g. stroke, spinal cord injury, normal aging).

Ambulatory Function and Perception of Confidence in Persons with Stroke with a Custom-Made Hinged versus a Standard Ankle Foot Orthosis

Objective. The aim was to compare walking with an individually designed dynamic hinged ankle foot orthosis (DAFO) and a standard carbon composite ankle foot orthosis (C-AFO). Methods. Twelve participants, mean age 56 years (range 26–72), with hemiparesis due to stroke were included in the study. During the six-minute walk test (6MW), walking velocity, the Physiological Cost Index (PCI), and the degree of experienced exertion were measured with a DAFO and C-AFO, respectively, followed by a Stairs Test velocity and perceived confidence was rated. Results. The mean differences in favor for the DAFO were in 6MW 24.3 m (95% confidence interval [CI] 4.90, 43.76), PCI −0.09 beats/m (95% CI −0.27, 0.95), velocity 0.04 m/s (95% CI −0.01, 0.097), and in the Stairs Test −11.8 s (95% CI −19.05, −4.48). All participants except one perceived the degree of experienced exertion lower and felt more confident when walking with the DAFO. Conclusions. Wearing a DAFO resulted in longer walking distance and faster stair climbing compared to walking with a C-AFO. Eleven of twelve participants felt more confident with the DAFO, which may be more important than speed and distance and the most important reason for prescribing an AFO.

Technology-based programs to improve walking behavior of persons with multiple disabilities: two single-case studies

PURPOSE

Assessing two technology-based programs for reducing toe walking and breaks during walking of two men with multiple disabilities, respectively.

METHOD

The men were involved in separate single-case studies, each of which was carried out according to an ABAB design. The technology included a microprocessor with specific software, optic sensors, and visual plus vibrotactile or auditory systems for presenting preferred stimuli. In Study I, the man received 1 s of preferred flickering lights and vibratory input for each step performed with the heel of the left foot touching the ground or coming close to it (i.e. within a 2-mm distance). In Study II, the other man received 10 s of preferred music anytime he crossed one of the small marks present along the travel routes.

RESULTS

The B phases showed that (a) the man included in Study I increased the percentages of left- and right-foot steps performed with the heels touching or nearing the ground to above 85% and 70%, respectively, and (b) the man included in Study II walked with very few breaks.

CONCLUSION

Technology-based programs can be highly effective in helping persons with multiple disabilities improve their walking behavior.

Technology-based programs to promote walking fluency or improve foot-ground contact during walking: two case studies of adults with multiple disabilities

These two case studies assessed technology-based programs for promoting walking fluency and improving foot-ground contact during walking with a man and a woman with multiple disabilities, respectively. The man showed breaks during walking and the woman presented with toe walking. The technology used in the studies included a microprocessor with specific software, an MP3 with the recordings of preferred stimulus items, and optic sensors. Both studies were carried out according to an ABAB design. In Study I, the optic sensors were activated when the man crossed small marks distributed along the travel routes. At each sensor's activation, the man received a brief period of preferred stimulation. In Study II, the woman received preferred stimulation when the sensors at the toe and the heel of her shoes were activated in close time proximity. The man walked virtually without breaks and improved his mood (with an increase in indices of happiness) during the intervention phases of the study. The woman largely increased her percentages of steps with adequate foot-ground contact, which reached a mean of about 80 during the second intervention phase. The results were discussed in terms of rehabilitation implications and technology demands.