Carbon Modular Orthosis (Ca.M.O.): An innovative hybrid modular ankle-foot orthosis to tune the variable rehabilitation needs in hemiplegic cerebral palsy

Exploring the rationale for prescribing ankle-foot orthoses and supramalleolar orthoses in children with cerebral palsy: A narrative synthesis of rationale statements

BACKGROUND

To help improve outcomes for children with cerebral palsy (CP), ankle-foot orthoses (AFOs) and supramalleolar orthoses (SMOs) are prescribed. However, it is not clear why one intervention is prescribed over the other.

OBJECTIVES

To explore the rationale for prescribing AFOs and SMOs in children with CP and its link to the choice of outcome measure used.

STUDY DESIGN

Narrative review.

METHODS

Six databases were searched (eg, Medline) and data extracted from articles that met the inclusion criteria. Data describing the participant demographics, type of orthosis, and outcome measures used were summarized to provide context for the different rationale for orthotic prescription that were thematically analyzed.

DISCUSSION

Forty-seven articles were included. Participants were aged 9 ± 2 years, 59% were male, 79% had diplegia, and 38% were classified as Gross Motor Function Classification System level I. All studies included a rationale for prescribing AFOs that, in most cases, reflected the outcome measures used. These rationale statements were synthesized into 5 specific themes (e.g., reduced energy expenditure and metabolic costs). By comparison, 5 of these studies described the rationale for providing SMOs, and of those that did, most of the rationale statements were nonspecific.

CONCLUSIONS

A large and contemporary body of literature describes the rationale for prescribing AFOs for children with CP. There are opportunities for future research that clearly articulates the rationale for prescribing SMOs for children living with CP and to focus the rational for orthotic intervention on the real-world challenges that are most important to children living with CP, such as the ability to participate among peers.

The Effect of a New Generation of Ankle Foot Orthoses on Sloped Walking in Children with Hemiplegia Using the Gait Real Time Analysis Interactive Lab (GRAIL)

Cerebral palsy poses challenges in walking, necessitating ankle foot orthoses (AFOs) for stability. Gait analysis, particularly on slopes, is crucial for effective AFO assessment. The study aimed to compare the performance of commercially available AFOs with a new sports-specific AFO in children with hemiplegic cerebral palsy and to assess the effects of varying slopes on gait. Eighteen participants, aged 6-11, with hemiplegia, underwent gait analysis using GRAIL technology. Two AFO types were tested on slopes (uphill +10 deg, downhill -5 deg, level-ground). Kinematic, kinetic, and spatiotemporal parameters were analyzed. The new AFO contributed to significant changes in ankle dorsi-plantar-flexion, foot progression, and trunk and hip rotation during downhill walking. Additionally, the new AFO had varied effects on spatiotemporal gait parameters, with an increased stride length during downhill walking. Slope variations significantly influenced the kinematics and kinetics. This study provides valuable insights into AFO effectiveness and the impact of slopes on gait in hemiplegic cerebral palsy. The findings underscore the need for personalized interventions, considering environmental factors, and enhancing clinical and research approaches for improving mobility in cerebral palsy.

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.

Analysis of Running Gait in Children with Cerebral Palsy: Barefoot vs. a New Ankle Foot Orthosis

Running is an essential activity for children with cerebral palsy (CP). This study aims to characterize the locomotor pattern of running in hemiplegic children with new generation ankle foot orthosis (AFOs) conceived to foster intense motor activities such as running. A group of 18 children with spastic hemiplegia was recruited. A biomechanical multivariable comparison was made between barefoot and with AFO running trials. The focus was devoted to bilateral sagittal plane hip, knee, ankle kinematics and kinetics, and three-dimensional ground reaction forces. Wearing the orthoses, the children were found to reduce cadence and the duration of the stance phase as well as increase the step and stride length. The new AFO resulted in significant changes in kinematics of affected ankle both at initial contact 0-3% GC (p < 0.017) and during the entire swing phase 31-100%GC (p < 0.001) being the ankle more dorsiflexed with AFO compared to barefoot condition. Ankle power was found to differ significantly both in absorption and generation 5-10%GC (p < 0.001); 21-27%GC (p < 0.001) with a reduction in both cases when the AFO was worn. No statistical differences were recorded in the GRF components, in the affected ankle torque and hip and knee kinematics and kinetics.

Robotic-assisted locomotor treadmill therapy does not change gait pattern in children with cerebral palsy

Although robotic-assisted locomotor treadmill therapy is utilized on children with cerebral palsy (CP), its impact on the gait pattern in childhood is not fully described. We investigated the outcome of robotized gait training focusing on the gait pattern modifications and mobility in individuals with CP. An additional intention is to compare our results with the previous literature advancing future solutions. Twenty-four children with diplegic CP (average age 6.4 years old with Gross Motor Functional Classification System range I-IV) received robotized gait training five times per week for 4 weeks. Gait analysis and Gross Motor Function Measurement (GMFM) assessments were performed before and at the end of the treatment. Gait analysis showed inconsistent modifications of the gait pattern. GMFM showed a mild improvement of the dimension D in all subjects, while dimension E changed only in the younger and more severely affected patients. In this study, a detailed investigation comprehensive of electromyography patterns, where previous literature reported only sparse data without giving information on the whole gait pattern, were conducted. We carried on the analysis considering the age of the participants and the severity of the gait function. The findings differentiate the concept of specific pattern recovery (no gait pattern changes) from the concept of physical training (mild GMFM changes).

Effectiveness comparison between carbon spring and hinged ankle-foot orthoses in crouch gait treatment of children with diplegic cerebral palsy: a randomized crossover trial

BACKGROUND

Children with cerebral palsy (CP) often present a loss of effectiveness of the plantarflexors/knee-extensors couple that leads to crouch gait. When treating a child with crouch gait by means of ankle foot orthoses, preserving or restoring push off power is a key issue.

AIM

To compare carbon-fiber spring (Carbon Ankle Seven® = CAFO) and hinged anklefoot orthoses (HAFO) effectiveness in improving functionality and walking ability in children with diplegic CP and crouch gait.

DESIGN

Randomized crossover trial.

SETTING

Hospital center.

POPULATION

Ten children with diplegic CP and crouch gait, 5 males and 5 females, aged 11 (4) years.

METHODS

The gait of each child was evaluated by means of instrumental gait analysis with both CAFO and HAFO, in a randomized order and after a 4-week adaptation period. The primary outcome measure was the change in ankle power generation. As secondary outcome measures, knee joint kinematics, stride length, walking speed, Observational Gait Scale, and preferred orthosis were considered.

RESULTS

The median of the energy produced in stance was superior with CAFO (+2.2 J/kg, IQR 4.7, p=0.006), and the energy absorbed inferior (-3.3 J/kg, IQR 4.3, p=0.011). No statistically significant difference was found for any other parameter. Preference of the children was equally distributed between the two orthoses.

CONCLUSIONS

No evident superiority of CAFO with respect to HAFO was found in improving gait performance of children with CP and crouch gait. Nevertheless, the results suggest the possibility that CAFO permits an energy saving and reduction of the more compromising deficits.

CLINICAL REHABILITATION IMPACT

The final choice of the participants indicates that CAFOs are preferred by older and heavier children, but the preference does not correlate with the performance of the orthoses during gait.

Control Reference Parameter for Stance Assistance Using a Passive Controlled Ankle Foot Orthosis—A Preliminary Study

This paper aims to present a preliminary study of control reference parameters for stance assistance among different subjects and walking speeds using a passive-controlled ankle foot orthosis. Four young male able-bodied subjects with varying body mass indexes (23.842 ± 4.827) walked in three walking speeds of 1, 3, and 5 km/h. Two control references, average ankle torque (aMa), and ankle angular velocity (aω), which can be implemented using a magnetorheological brake, were measured. Regression analysis was conducted to identify suitable control references in the three different phases of the stance. The results showed that aω has greater correlation (p) with body mass index and walking speed compared to aMa in the whole stance phase (p1(aω) = 0.666 > p1(aMa) = 0.560, p2(aω) = 0.837 > p2(aMa) = 0.277, and p3(aω) = 0.839 > p3(aMa) = 0.369). The estimation standard error (Se) of the aMa was found to be generally higher than of aω (Se1(aMa) = 2.251 > Se1(aω) = 0.786, Se2(aMa) = 1.236 > Se2(aω) = 0.231, Se3(aMa) = 0.696 < Se3(aω) = 0.755). Future studies should perform aω estimation based on body mass index and walking speed, as suggested by the higher correlation and lower standard error as compared to aMa. The number of subjects and walking speed scenarios should also be increased to reduce the standard error of control reference parameters estimation.

A Review on the Control of the Mechanical Properties of Ankle Foot Orthosis for Gait Assistance

In the past decade, advanced technologies in robotics have been explored to enhance the rehabilitation of post-stroke patients. Previous works have shown that gait assistance for post-stroke patients can be provided through the use of robotics technology in ancillary equipment, such as Ankle Foot Orthosis (AFO). An AFO is usually used to assist patients with spasticity or foot drop problems. There are several types of AFOs, depending on the flexibility of the joint, such as rigid, flexible rigid, and articulated AFOs. A rigid AFO has a fixed joint, and a flexible rigid AFO has a more flexible joint, while the articulated AFO has a freely rotating ankle joint, where the mechanical properties of the AFO are more controllable compared to the other two types of AFOs. This paper reviews the control of the mechanical properties of existing AFOs for gait assistance in post-stroke patients. Several aspects that affect the control of the mechanical properties of an AFO, such as the controller input, number of gait phases, controller output reference, and controller performance evaluation are discussed and compared. Thus, this paper will be of interest to AFO researchers or developers who would like to design their own AFOs with the most suitable mechanical properties based on their application. The controller input and the number of gait phases are discussed first. Then, the discussion moves forward to the methods of estimating the controller output reference, which is the main focus of this study. Based on the estimation method, the gait control strategies can be classified into subject-oriented estimations and phase-oriented estimations. Finally, suggestions for future studies are addressed, one of which is the application of the adaptive controller output reference to maximize the benefits of the AFO to users.

Non-invasive Focal Mechanical Vibrations Delivered by Wearable Devices: An Open-Label Pilot Study in Childhood Ataxia

Non-invasive focal mechanical vibrations (NIFMV) now represent a strategy of increasing interest to improve motor control in different neurological diseases. Nanotechnology allowed the creation of wearable devices transforming thermal variations into mechanical energy with focal vibrations. This kind of wearable stimulators (WS) has produced encouraging preliminary results when used in the treatment of movement disorders and ataxia in adults. In this open label pilot study we first evaluated the feasibility, safety and effectiveness of NIFMV by WS in a cohort of 10 patients with childhood ataxia, a phenomenological category including different conditions still lacking of effective symptomatic therapies. Through the assessment of both clinical rating scales and spatio-temporal gait parameters via standardized gait analysis, we observed that a 4 weeks long treatment with WS Equistasi® was safe and provided significantly different effects in stride features of patients with slow/non-progressive cerebellar ataxia and Friedreich's Ataxia. Although limited by the sample size, the absence of a placebo-controlled group, the poor compliance of enrolled population to the original experimental design and the partial accuracy of outcome measures in pediatric subjects, we suggest that NIFMV by WS could support locomotion of patients with childhood slow/non-progressive cerebellar ataxia with preserved sensory system and no signs of peripheral neuropathy. Future studies are definitely necessary to confirm these preliminary results and define criteria for successful NIFMV-based treatment

Effect of ankle-foot orthoses on gait, balance and gross motor function in children with cerebral palsy: a systematic review and meta-analysis

Objective:

To determine the effects of ankle-foot orthoses (AFOs) on gait, balance, gross motor function and activities of daily living in children with cerebral palsy.

Data sources:

Five databases were searched (Pubmed, Psycinfo, Web of Science, Academic Search Premier and Cochrane Library) before January 2018.

Review methods:

Studies of the effect of AFOs on gait, balance, gross motor function and activities of daily living in children with cerebral palsy were included. Articles with a modified PEDRO score ≥ 5/9 were selected. Data regarding population, AFO, interventions and outcomes were extracted. When possible, standardized mean differences (SMDs) were calculated from the outcomes.

Results:

Thirty-two articles, corresponding to 56 studies (884 children) were included. Fifty-one studies included children with spastic cerebral palsy. AFOs increased stride length (SMD = 0.88, P < 0.001) and gait speed (SMD = 0.28, P < 0.001), and decreased cadence (SMD = –0.72, P < 0.001). Gross motor function scores improved (Gross Motor Function Measure (GMFM) D (SMD = 0.30, P = 0.004), E (SMD = 0.28, P = 0.02), Pediatric Evaluation of Disability Inventory (PEDI) (SMD = 0.57, P < 0.001)). Data relating to balance and activities of daily living were insufficient to conclude. Posterior AFOs (solid, hinged, supra-malleolar, dynamic) increased ankle dorsiflexion at initial contact (SMD = 1.65, P < 0.001) and during swing (SMD = 1.34, P < 0.001), and decreased ankle power generation in stance (SMD = –0.72, P < 0.001) in children with equinus gait.

Conclusion:

In children with spastic cerebral palsy, there is strong evidence that AFOs induce small improvements in gait speed and moderate evidence that AFOs have a small to moderate effect on gross motor function. In children with equinus gait, there is strong evidence that posterior AFOs induce large changes in distal kinematics.