Bidirectional Tuning of the AFO Stiffness

NCT06412055 | Recruiting DMC

• 1 other identifier: NL85684.018.23
• Study Type: interventional
• Target: 10
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this pilot study with a pre-post design is to investigate the effects of separate individualization of the AFO stiffness towards plantar- and dorsiflexion in a spring-hinged AFO on walking compared to a spring-like AFO (3 types) having the same stiffness in both directions. People with a neuromuscular disease or nerve injury causing at least plantarflexor weakness (determined as the inability to perform 3 single heel rises), with an indication for or using an AFO, will be fitted with a new, custom-made spring-hinged AFO with the NEURO SWING® system ankle joint (Fior\& Gentz, Lüneburg, Germany), of which the stiffness of ventral and dorsal compartment of this spring-hinged AFO will be individualized. For comparison, measurements will be performed with three different prefab spring-like AFOs with different stiffness levels (but which have a similar stiffness towards plantar and dorsiflexion), and the participants' current AFO if applicable, and shoes-only at baseline. The main outcome parameters will be the maximal ankle plantarflexion angle, ankle angular velocity and knee flexion angle during the loading response, which will be measured using a 3D gait analysis. Secondary outcomes include other gait biomechanics, walking energy cost, walking speed, standing balance, perceived physical functioning and perceived walking ability.

Conditions

Neuromuscular Disorders

Keywords

Neuromuscular disorders; dorsiflexor and plantarflexor weakness; ankle-foot orthosis (AFO); bidirectional stiffness tuning; Gait kinetics and kinematics; Walking energy cost; Perceived physical functioning

Outcome Measures

Primary Outcomes (1)

• maximal ankle angular velocity in loading response in degrees

  measured during a 3D gait analysis

  day 0 (directly post-delivery)

Secondary Outcomes (18)

• maximal ankle angular velocity in loading response

  6 weeks post-delivery for the stiffness-optimized NEURO SWING AFO

• minimal ankle angle in loading response in degrees

  day 0 (directly post-delivery) and 6 weeks post-delivery for the stiffness-optimized NEURO SWING AFO only

• ankle angle during midstance in degrees

  day 0 (directly post-delivery) and 6 weeks post-delivery for the stiffness-optimized NEURO SWING AFO only

• maximal ankle angle during the stance phase in degrees

  day 0 (directly post-delivery) and 6 weeks post-delivery for the stiffness-optimized NEURO SWING AFO only

• maximal ankle moment in Nm/kg

  day 0 (directly post-delivery) and 6 weeks post-delivery for the stiffness-optimized NEURO SWING AFO only

Other Outcomes (1)

• number of participants with adverse events

  from baseline to 6 weeks post-delivery of the stiffness-optimized NEURO SWING AFO

Study Arms (1)

NEURO SWING AFO

EXPERIMENTAL

Participants will be fitted with a new custom-made spring-hinged AFO with the NEURO SWING® system ankle joint. Following a previously developed algorithm, the stiffness will be individually selected from six different configurations tested during an optimization measurement directly after delivery of the new AFO. Thereafter, participants will use the optimized AFO with individualized stiffness at home for six weeks during the course of the study.

Device: NEURO SWING AFO (Fior& Gentz, Lüneburg, Germany); Device: WalkOn Reaction® (Ottobock, Duderstadt); Device: Matrix Max2® (TruLife, Dublin, Ireland); Device: Matrix® (TruLife, Dublin, Ireland)

Interventions

NEURO SWING AFO (Fior& Gentz, Lüneburg, Germany) DEVICE

stiffness-optimized custom-made spring-hinged AFO with the NEURO SWING® system ankle joint build in

NEURO SWING AFO

WalkOn Reaction® (Ottobock, Duderstadt) DEVICE

comparator: prefab spring-like AFO without hinge with a predefined stiffness (2.8 Nm/degree).

NEURO SWING AFO

Matrix Max2® (TruLife, Dublin, Ireland) DEVICE

comparator: prefab spring-like AFO without hinge with a predefined stiffness (1.4 Nm/degree)

NEURO SWING AFO

Matrix® (TruLife, Dublin, Ireland) DEVICE

comparator: prefab spring-like AFO without hinge with a predefined stiffness (0.6 Nm/degree)

NEURO SWING AFO

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age 18 years or older;
• Presence of plantar flexor weakness in at least one leg, determined as a score lower than 5 on the manual muscle testing scale (Medical Research Council- MRC) and/or inability to perform three single heel rises, with or without dorsiflexion weakness;
• Indicated for or using an AFO;
• Ability to walk 6-minutes consecutively (with assistive device, if necessary).

You may not qualify if:

• When wearing the AFO, not able to walk short bouts of 10m without walking aids, such as a walker;
• Foot deformities that do not fit in prefab spring-like AFOs;
• Weakness of the knee extensor muscles, for which a knee-ankle-foot orthosis is indicated.

Sponsors & Collaborators

• Academisch Medisch Centrum - Universiteit van Amsterdam (AMC-UvA): lead
• FIOR & GENTZ: collaborator

Study Sites (1)

Department of rehabilitation medicine Amsterdam UMC, location AMC

Amsterdam, 1105AZ, Netherlands

RECRUITING

MeSH Terms

Conditions

Neuromuscular Diseases

Condition Hierarchy (Ancestors)

Nervous System Diseases

Study Officials

• Frans Nollet, MD PhD

  Amsterdam UMC, location AMC

  STUDY DIRECTOR

Central Study Contacts

Merel-Anne Brehm, PhD

CONTACT

+ 3120 5664049; m.a.brehm@amsterdamumc.nl

Elza van Duijnhoven

CONTACT

+3120 5666915; e.vanduijnhoven@amsterdamumc.nl

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Model Details: pilot self-controlled intervention study with measurements of three spring-like AFOs (WalkOn Reaction® (Ottobock, Duderstadt), the Matrix Max2® (TruLife, Dublin, Ireland), and the Matrix® (TruLife, Dublin, Ireland)) having the same stiffness in both directions, and a newly custom-made spring-hinged AFO with the NEURO SWING® system ankle joint with individualized spring settings (Fior\& Gentz, Lüneburg, Germany) directly after delivery and 6 weeks post-delivery.

Study Record Dates

• First Submitted: May 2, 2024
• First Posted: May 14, 2024
• Study Start: May 15, 2024
• Primary Completion: February 1, 2025
• Study Completion: February 1, 2025
• Last Updated: February 5, 2025

Record last verified: 2025-02

Data Sharing

• IPD Sharing: Will share

Locations

NL (1)