Trends and Technologies in Rehabilitation of Foot Drop: A Systematic Review

Foot drop in critically ill patients: a narrative review of an elusive complication with intricate implications for recovery and rehabilitation

Foot drop is a condition characterized by the inability to lift the foot upwards towards the shin bone. This condition may affect a proportion of critically ill patients, impacting on their recovery after the acute phase of the illness. The occurrence of foot drop in critical care patients may result from various underlying causes, including neurological injuries, muscular dysfunction, nerve compression, or vascular compromise. Understanding the etiology and assessing the severity of foot drop in these patients is essential for implementing appropriate management strategies and ensuring better patient outcomes. In this comprehensive review, we explore the complexities of foot drop in critically ill patients. We search for the potential risk factors that contribute to its development during critical illness, the impact it has on patients' functional abilities, and the various diagnostic techniques adopted to evaluate its severity. Additionally, we discuss current treatment approaches, rehabilitation strategies, and preventive measures to mitigate the adverse effects of foot drop in the critical care setting. Furthermore, we explore the roles of critical care physical therapists, neurologists, and other healthcare professionals in the comprehensive care of patients with foot drop syndrome and in such highlighting the importance of a multidisciplinary approach.

Is functional electrical stimulation effective in improving walking in adults with lower limb impairment due to an upper motor neuron lesion? An umbrella review

PURPOSE

To conduct an umbrella review of systematic reviews on functional electrical stimulation (FES) to improve walking in adults with an upper motor neuron lesion.

METHODS

Five electronic databases were searched, focusing on the effect of FES on walking. The methodological quality of reviews was evaluated using AMSTAR2 and certainty of evidence was established through the GRADE approach.

RESULTS

The methodological quality of the 24 eligible reviews (stroke, n = 16; spinal cord injury (SCI), n = 5; multiple sclerosis (MS); n = 2; mixed population, n = 1) ranged from critically low to high. Stroke reviews concluded that FES improved walking speed through an orthotic (immediate) effect and had a therapeutic benefit (i.e., over time) compared to usual care (low certainty evidence). There was low-to-moderate certainty evidence that FES was no better or worse than an Ankle Foot Orthosis regarding walking speed post 6 months. MS reviews concluded that FES had an orthotic but no therapeutic effect on walking. SCI reviews concluded that FES with or without treadmill training improved speed but combined with an orthosis was no better than orthosis alone. FES may improve quality of life and reduce falls in MS and stroke populations.

CONCLUSION

FES has orthotic and therapeutic benefits. Certainty of evidence was low-to-moderate, mostly due to high risk of bias, low sample sizes, and wide variation in outcome measures. Future trials must be of higher quality, use agreed outcome measures, including measures other than walking speed, and examine the effects of FES for adults with cerebral palsy, traumatic and acquired brain injury, and Parkinson's disease.

Ankle dorsiflexion assistance of patients with foot drop using a powered ankle-foot orthosis to improve the gait asymmetry

BACKGROUND

Foot drop is a neuromuscular disorder that causes abnormal gait patterns. This study developed a pneumatically powered ankle-foot orthosis (AFO) to improve the gait patterns of patients with foot drop. We hypothesized that providing unilateral ankle dorsiflexion assistance during the swing phase would improve the kinematics and spatiotemporal gait parameters of such patients. Accordingly, this study aims to examine the efficacy of the proposed assistance system using a strategy for joint kinematics and spatiotemporal gait parameters (stride length, swing velocity, and stance phase ratio). The analysis results are expected to provide knowledge for better design and control of AFOs in patients with foot drop.

METHOD

Ten foot drop patients with hemiparesis (54.8 y ± 14.1 y) were fitted with a custom AFO with an adjustable calf brace and portable air compressor for ankle dorsiflexion assistance in the gait cycle during the swing phase. All subjects walked under two different conditions without extensive practice: (1) barefoot and (2) wearing a powered AFO. Under each condition, the patients walked back and forth on a 9-m track with ten laps of level ground under the supervision of licensed physical therapists. The lower-limb joint and trunk kinematics were acquired using 12 motion-capture cameras.

RESULTS

We found that kinematic asymmetry decreased in the three lower-limb joints after ankle dorsiflexion assistance during the swing phase. The average ankle-joint angle increased after using the AFO during the entire gait cycle. Similarly, the knee-joint angle showed a slight increase while using the AFO, leading to a significantly decreased standard deviation within patients. Conversely, the hip-joint angle showed no significant improvements with assistance. While several patients exhibited noticeably lower levels of asymmetry, no significant changes were observed in the average asymmetry of the swing velocity difference between the affected and unaffected sides while using the AFO.

CONCLUSION

We experimentally validated that ankle dorsiflexion assistance during the swing phase temporarily improves gait asymmetry in foot-drop patients. The experimental results also prove the efficacy of the developed AFO for gait assistance in foot-drop patients.

Acute Foot Drop Caused by Intraneural Ganglion Cyst of the Peroneal Nerve: Literature Review and Case Report

BACKGROUND

Foot drop (FD) is characterized by an inability to lift the foot against gravity because of dorsiflexor muscle weakness. The aim of the present study is to report a clinical case of acute non-traumatic FD in patients with peroneal intraneural ganglion, after performing a scoping review on the methodological management of this disease.

METHODS

We performed a review of the literature and reported the case of a 49-year-old man with acute FD caused by an intraneural ganglion cyst of the peroneal nerve.

RESULTS

Out of a total of 201 articles, 3 were suitable for our review beyond our case report. The acute FD caused by peroneal intraneural ganglion can be managed by a careful clinical-instrumental differential diagnosis. A targeted surgery with subsequent rehabilitation produced a satisfactory motor recovery.

CONCLUSIONS

Acute FD requires an appropriate diagnostic-therapeutic framework to identify and effectively treat the causes in order to promote complete recovery.

Functional Benefit and Orthotic Effect of Dorsiflexion-FES in Children with Hemiplegic Cerebral Palsy

Functional electrical stimulation of the ankle dorsiflexor (DF-FES) may have advantages over ankle foot orthoses (AFOs) in managing pediatric cerebral palsy (CP). This study assessed the functional benefit and orthotic effect of DF-FES in children with hemiplegic CP. We conducted an open-label prospective study on children with hemiplegic CP ≥ 6 years who used DF-FES for five months. The functional benefit was assessed by repeated motor function tests and the measurement of ankle biomechanical parameters. Kinematic and spatiotemporal parameters were assessed by gait analysis after one and five months. The orthotic effect was defined by dorsiflexion ≥ 0° with DF-FES at either the mid or terminal swing. Among 26 eligible patients, 15 (median age 8.2 years, range 6-15.6) completed the study. After five months of DF-FES use, the results on the Community Balance and Mobility Scale improved, and the distance in the Six-Minute Walk Test decreased (six-point median difference, 95% CI (1.89, 8.1), -30 m, 95% CI (-83.67, -2.6), respectively, p < 0.05) compared to baseline. No significant changes were seen in biomechanical and kinematic parameters. Twelve patients (80%) who showed an orthotic effect at the final gait analysis experienced more supported walking over time, with a trend toward slower walking. We conclude that the continuous use of DF-FES increases postural control and may cause slower but more controlled gait.

Application of an adjustable medical foot support pillow to prevent foot drop in patients with stroke

BACKGROUND: Foot drop is one of the most common complications after stroke. OBJECTIVE: This study investigates the role of an adjustable medical foot support pillow in preventing foot drop and improving the lower limb function of patients after stroke. METHODS: A total of 88 patients with strokes admitted to our hospital from September 2019 to September 2020 were selected and categorised into the control (n= 44) and intervention groups (n= 44) using a random number table. The control group received routine rehabilitation nursing, while the intervention group adopted a self-made adjustable medical foot support pillow based on routine rehabilitation nursing. After four weeks, the simplified Fugl Meyer Assessment (FMA) and the modified activities of daily living (ADL) scales were used to measure the ankle range of motion of the lower limbs. The lower limb motor function, ADL, and ankle mobility before and after treatment, as well as the incidence of foot ptosis, were compared between the two groups. RESULTS: After the procedure, the intervention group was superior to the control group in the FMA score of the lower extremities, ADL score, and ankle joint mobility in the lower limbs, indicating statistically significant differences (P< 0.05). The incidence rate of foot drop was lower in the intervention group than in the control group, and the difference was statistically significant (P< 0.05). CONCLUSION: The adjustable medical foot support pillow can prevent foot drop in patients after stroke, improve lower limb function, provide a favourable basis for walking training, and improve the ADL of patients.

Review of ankle rehabilitation devices for treatment of equinus contracture

INTRODUCTION

Equinus contracture is a serious disability and attention should be paid to proper and effective treatment. Most attention is given to neurologically impaired patients, but the incidence of equinus contracture is much higher, for example, in post-traumatic patients. In addition to conventional physical therapy, robotic rehabilitation treatment is one of the promising procedures to precede severe contraction cases and the need for surgery.

AREAS COVERED

This study aims to cover the description of different types of stationary and wearable ankle rehabilitation devices suitable for the treatment of equinus contracture and point to deficiency in research, clinical trials, and launch of the market.

EXPERT OPINION

This review provides insight into ankle rehabilitation devices with a focus on equinus contracture. Due to the fact that robotic devices successfully restore the condition of patients, attention should not be paid only to those with neurological impairments. This paper points that future research should be effectively linked to clinical practice with the aim of covering a wider range of disabilities and make an effort to successfully introduce devices from development into the practice.

Research and Development of Ankle-Foot Orthoses: A Review

The ankle joint is one of the important joints of the human body to maintain the ability to walk. Diseases such as stroke and ankle osteoarthritis could weaken the body's ability to control joints, causing people's gait to be out of balance. Ankle-foot orthoses can assist users with neuro/muscular or ankle injuries to restore their natural gait. Currently, passive ankle-foot orthoses are mostly designed to fix the ankle joint and provide support for walking. With the development of materials, sensing, and control science, semi-active orthoses that release mechanical energy to assist walking when needed and can store the energy generated by body movement in elastic units, as well as active ankle-foot orthoses that use external energy to transmit enhanced torque to the ankle, have received increasing attention. This article reviews the development process of ankle-foot orthoses and proposes that the integration of new ankle-foot orthoses with rehabilitation technologies such as monitoring or myoelectric stimulation will play an important role in reducing the walking energy consumption of patients in the study of human-in-the-loop models and promoting neuro/muscular rehabilitation.

Optimal Assistance Timing to Induce Voluntary Dorsiflexion Movements: A Preliminary Study in Healthy Participants

Swing-phase dorsiflexion assistance with robotic ankle–foot orthosis could improve toe clearance and limb shortening such that compensatory movements are suppressed. However, facilitating voluntary effort under assistance remains a challenge. In our previous study, we examined assistance effects of swing-phase dorsiflexion with different delay times after toe-off on a dorsiflexion-restricted gait with a high-dorsiflexion assistive system. Results showed that later dorsiflexion assistance could lead to an increase in the tibialis anterior’s surface electromyography but could also deteriorate compensatory movement. Thus, we concluded that there is a suitable assistance timing to simultaneously achieve voluntary effort and optimal gait. In the present research, we derived a method to identify a suitable dorsiflexion assistance delay time via a multiple linear regression analysis on ankle data of stroke patients with a pathological gait with insufficient dorsiflexion. With the identification method, an experiment was conducted on six healthy participants with restricted dorsiflexion. Results showed that the identified assistance timing improved the amplitude of the tibialis anterior’s surface electromyography while also suppressing limb shortening during circumduction and hip hiking. Although a practical study of stroke survivors is required, observations from this research indicate the potential to successfully induce voluntary efforts with the identified dorsiflexion assistance timing.

High-Dorsiflexion Assistive System for Passive Swing Phase Dorsiflexion Training and Preventing Compensatory Movements

Over the last few years, numerous robotic ankle-foot orthoses have been developed to help stroke patients optimize gait rehabilitation. In this paper, we present a study on the effects of assistance on dorsiflexion-restricted gait. Our high-dorsiflexion assistive system aims to provide full assistance to realize passive training of dorsiflexion during the swing phase and prevent compensatory movements. This system, which includes a McKibben-type artificial muscle and an air source, is lightweight and provides a high-dorsiflexion torque. The device could help boost overground gait rehabilitation in stroke patients. With this system, we conducted an experiment on five healthy participants whose dorsiflexion movements were restricted, and the extent of their compensatory movements differed. The results of the processed surface electromyography data differed significantly when dorsiflexion movement was assisted by our system. The spatial parameters also showed significantly improved compensatory movement inclination with sufficient assistance. These results indicate the potential of our system to assist in passive training of ankle dorsiflexion movements and to prevent incorrect gait in patients with low dorsiflexion abilities.

Necessity and Content of Swing Phase Gait Coordination Training Post Stroke; A Case Report

Background/Problem: Standard neurorehabilitation and gait training has not proved effective in restoring normal gait coordination for many stroke survivors. Rather, persistent gait dyscoordination occurs, with associated poor function, and progressively deteriorating quality of life. One difficulty is the array of symptoms exhibited by stroke survivors with gait deficits. Some researchers have addressed lower limb weakness following stroke with exercises designed to strengthen muscles, with the expectation of improving gait. However, gait dyscoordination in many stroke survivors appears to result from more than straightforward muscle weakness.

PURPOSE

Thus, the purpose of this case study is to report results of long-duration gait coordination training in an individual with initial good strength, but poor gait swing phase hip/knee and ankle coordination.

METHODS

Mr. X was enrolled at >6 months after a left hemisphere ischemic stroke. Gait deficits included a 'stiff-legged gait' characterized by the absence of hip and knee flexion during right mid-swing, despite the fact that he showed good initial strength in right lower limb quadriceps, hamstrings, and ankle dorsiflexors. Treatment was provided 4 times/week for 1.5 h, for 12 weeks. The combined treatment included the following: motor learning exercises designed for coordination training of the lower limb; functional electrical stimulation (FES) assisted practice; weight-supported coordination practice; and over-ground and treadmill walking. The FES was used as an adjunct to enhance muscle response during motor learning and prior to volitional recovery of motor control. Weight-supported treadmill training was administered to titrate weight and pressure applied at the joints and to the plantar foot surface during stance phase and pre-swing phase of the involved limb. Later in the protocol, treadmill training was administered to improve speed of movement during the gait cycle. Response to treatment was assessed through an array of impairment, functional mobility, and life role participation measures.

RESULTS

At post-treatment, Mr. X exhibited some recovery of hip, knee, and ankle coordination during swing phase according to kinematic measures, and the stiff-legged gait was resolved. Muscle strength measures remained essentially constant throughout the study. The modified Ashworth scale showed improved knee extensor tone from baseline of 1 to normal (0) at post-treatment. Gait coordination overall improved by 12 points according to the Gait Assessment and Intervention Tool, Six Minute Walk Test improved by 532', and the Stroke Impact Scale improved by 12 points, including changes in daily activities; mobility; and meaningful activities.

DISCUSSION

Through the combined use of motor learning exercises, FES, weight-support, and treadmill training, coordination of the right lower limb improved sufficiently to exhibit a more normal swing phase, reducing the probability of falls, and subsequent downwardly spiraling dysfunction. The recovery of lower limb coordination during swing phase illustrates what is possible when strength is sufficient and when coordination training is targeted in a carefully titrated, highly incrementalized manner. Conclusions/Contribution to the Field: This case study contributes to the literature in several ways: (1) illustrates combined interventions for gait training and response to treatment; (2) provides supporting case evidence of relationships among knee flexion coordination, swing phase coordination, functional mobility, and quality of life; (3) illustrates that strength is necessary, but not sufficient to restore coordinated gait swing phase after stroke in some stroke survivors; and (4) provides details regarding coordination training and progression of gait training treatment for stroke survivors.

Effects of Assisted Dorsiflexion Timing on Voluntary Efforts and Compensatory Movements: A Feasibility Study in Healthy Participants

In previous research, we found that modulating the assistance timing of dorsiflexion may affect a user's voluntary efforts. This could constitute a focus area based on assistive strategies that could be developed to foster patients' voluntary efforts. In this present study, we conducted an experiment to verify the effects of ankle dorsiflexion assistance under different timings using a high-dorsiflexion assistive system. Nine healthy and young participants wore a dorsiflexion-restrictive device that enabled them to use circumduction or steppage gaits. On the basis of the transition from the stance to the swing phase of the gait, the assistance timings of the high-dorsiflexion assistive system were set to have delays, which ranged from 0 to 300 ms. The index results from eight out of nine participants evaluated compensatory movements and revealed positive strong/moderate correlations with assistance delay times (r = 0.627-0.965, p <.001), whereas the other participants also performed compensatory movement when dorsiflexion assistance timing was late. Meanwhile, the results from tibialis anterior surface electromyography from six out of nine participants showed positive strong/moderate correlations with dorsiflexion assistance delay times (r = 0.598-0.922, p <.001), indicating that tuning the assistance timing did foster these participants' voluntary dorsiflexion movements. This result indicates that there should be a trade-off between ensuring voluntary dorsiflexion movements and preventing incorrect gait patterns at different assistance timings. The findings of this feasibility study indicate the potential of developing an adaptive control method to ensure voluntary efforts during robot-assisted gait rehabilitation based on assistance timing modification. A new assistance mechanism should also be required to stimulate and motivate a patient's voluntary efforts and should reinforce the effects of active gait rehabilitation.