Influence of Immobilisation, Stretching and Activity on Morphological and Mechanical Properties of Spastic Muscle

NCT05269745 | Completed

• 1 other identifier: 25940
• Study Type: interventional
• Target: 14
• Locations: 1 country
• Sites: 1

Brief Summary

Neurologic changes caused by cerebral palsy (CP) result in adaptation of muscle architecture and function (e.g. shortened muscles and contractures). Stretching through immobilization (orthotic treatment) is one of the common interventions to bring the spastic muscle to growth. Positive outcomes of stretching through immobilization are increased range of motion and improved function. On the other hand, immobilization leads to disuse muscle atrophy. Hence, we hypothesize that combining a stretching through immobilization and muscle activity while controlling for foot deformity could be a superior treatment approach, which should lead to improved muscle morphology as well as function. The aim of the study is to examine the influence of two orthotic treatments (a standard regime and one new approach) on spastic plantar flexor muscles in children and adolescents with CP. The standard regime (stretching through immobilisation) includes a dynamic AFO (ankle-foot orthosis) used during day and night. The new approach combines stretching through immobilisation and allows for plantarflexor activity due to an innovative construction of the orthotic device. This prospective randomized controlled study will recruit 20 ambulant children and adolescents (aged 5 to 15 years) with cerebral palsy and equinus deformity (GMFCS = Gross Motor Function Classification System level I to III). Each child will be randomized and stratified according to age and GMFCS to one of two groups. The first group receives the standard treatment (stretching through immobilization) using custom-made ankle foot orthosis for 23 hours per day. The other group will be treated with the same orthosis at night (8 hours) and for 6 hours during the day but the remaining 10 hours will be treated with the foot shell only that corrects subtalar and Chopart joints but does not block the ankle joint movement, so that more activity of plantarflexors will be possible during the day. The intervention will last for 12 weeks. Each child will be examined at four occasions (8 weeks before intervention = control phase, at the beginning of the intervention and then 8 and 12 weeks later). The main outcome measure is the fascicle length measured using a 3D ultrasound (3DUS) imaging technique. Further parameters of interest span across the whole levels of ICF including clinical examinations, biomechanics of gait, muscle morphologic and mechanic properties and participations questionnaires.

Conditions

Cerebral Palsy, Spastic

Outcome Measures

Primary Outcomes (8)

• Change in mechano-morphological muscle-tendon properties - muscle volume

  Gastrocnemius medialis muscle volume

  Time Frame: baseline (T1), PRE-measurement (T2, 8 weeks), POST-measurement (T3, 16 weeks), FOLLOW-UP measurement (T4, 20 weeks)

• Change in mechano-morphological muscle-tendon properties - fascile length

  Gastrocnemius medialis fascile length

  Time Frame: baseline (T1), PRE-measurement (T2, 8 weeks), POST-measurement (T3, 16 weeks), FOLLOW-UP measurement (T4, 20 weeks)

• Change in mechano-morphological muscle-tendon properties - unit length

  Gastrocnemius medialis muscle belly, tendon and muscle-tendon unit length

  Time Frame: baseline (T1), PRE-measurement (T2, 8 weeks), POST-measurement (T3, 16 weeks), FOLLOW-UP measurement (T4, 20 weeks)

• Change in mechano-morphological muscle-tendon properties - elongation

  Passive gastrocnemius medialis muscle belly, tendon and muscle-tendon unit elongation due to externally applied torque to the ankle joint \[elongation in mm\]

  Time Frame: baseline (T1), PRE-measurement (T2, 8 weeks), POST-measurement (T3, 16 weeks), FOLLOW-UP measurement (T4, 20 weeks)

• Change in mechano-morphological muscle-tendon properties - stiffness

  Passive gastrocnemius medialis muscle belly, tendon and muscle-tendon unit stiffness due to externally applied torque to the ankle joint \[stiffness in N/mm\]

  Time Frame: baseline (T1), PRE-measurement (T2, 8 weeks), POST-measurement (T3, 16 weeks), FOLLOW-UP measurement (T4, 20 weeks)

• Change in joint range of motion

  Ankle joint range of motion (maximal plantarflexion - maximal dorsiflexion)

  Time Frame: baseline (T1), PRE-measurement (T2, 8 weeks), POST-measurement (T3, 16 weeks), FOLLOW-UP measurement (T4, 20 weeks)

• Change in maximal isometric muscle strength

  Maximal isometric torque production (isokinetic dynamometry)

  Time Frame: baseline (T1), PRE-measurement (T2, 8 weeks), POST-measurement (T3, 16 weeks), FOLLOW-UP measurement (T4, 20 weeks)

• Change in gait characteristics

  Gait kinematics (joint angles \[°\]) and kinetics (joint moments \[Nm/kg\]) of the hip, knee, and ankle joints (3D motion capture). Joint angles \[°\] and moments \[Nm/kg\] will be combined to report changes in gait pattern.

  Time Frame: baseline (T1), PRE-measurement (T2, 8 weeks), POST-measurement (T3, 16 weeks), FOLLOW-UP measurement (T4, 20 weeks)

Secondary Outcomes (2)

• Change in self-reported gait, mobility, and functional performance - GOAL

  Time Frame: baseline (T1), PRE-measurement (T2, 8 weeks), POST-measurement (T3, 16 weeks), FOLLOW-UP measurement (T4, 20 weeks)

• Change in self-reported gait, mobility, and functional performance - PODCI

  Time Frame: baseline (T1), PRE-measurement (T2, 8 weeks), POST-measurement (T3, 16 weeks), FOLLOW-UP measurement (T4, 20 weeks)

Study Arms (3)

Immobilization group (IG)

ACTIVE COMPARATOR

One group - immobilization group (IG) - will receive the standard treatment.

Other: Stretching through immobilisation (IG)

Immobilization/Activity Group (IAG)

EXPERIMENTAL

The other group - Immobilization/Activity Group (IAG) - will be treated with a new approach.

Other: Stretching through immobilisation and activity (IAG)

Control Phase

OTHER

Before the intervention with the orthotic treatment starts, a control phase of 8 weeks is planned.

Other: Control Phase

Interventions

Stretching through immobilisation (IG) OTHER

The immobilization group (IG) will receive the standard treatment, a dynamic ankle-foot orthosis (AFO) for night and day use (23 hours per day)

Also known as: IG

Immobilization group (IG)

Stretching through immobilisation and activity (IAG) OTHER

The Immobilization/Activity Group (IAG) will be treated with the same type of ankle-foot orthosis at night (8 hours) and for 6 hours during the day (altogether orthosis treatment 14 hours per day). The rest of the day (10 hours) children and adolescents will be using only the foot shell of orthoses (FS) without the lower leg shell, to secure the correct position of the foot and to allow a free motion at ankle joint with a good correction of the foot deformity (e.g. Pes equinovarus / equinovalgus, midfoot-break).

Also known as: IAG

Immobilization/Activity Group (IAG)

Control Phase OTHER

Before the intervention with the orthotic treatment starts, a control phase of 8 weeks is planned. During this time, the individual orthoses for each subject are manufactured.

Control Phase

Eligibility Criteria

• Age: 5 Years - 15 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17)

You may qualify if:

• Ambulatory children with spastic CP.
• Ability to accept and follow verbal instruction.
• Limited range of motion in ankle joint - maximal dorsiflexion with knee extended ≤ 5°
• Gross Motor Functional Classification System level I-III.
• Age 5-15 years.
• Willingness to participate.

You may not qualify if:

• Other than spastic form of CP (ataxic, athetoid or dystonic).
• Severe mental retardation.
• Normal range of motion in ankle joint
• Oral antispastic or muscle relaxing medication.
• History of orthopaedic surgery in the last 12 months.
• History of botulinum toxin type A application in the last six months.

Sponsors & Collaborators

• Medical University of Graz: lead
• University of Graz: collaborator

Study Sites (1)

Medical University Graz

Graz, Styria, 8036, Austria

Location

MeSH Terms

Conditions

Cerebral Palsy

Interventions

Exercise; G2 Phase Cell Cycle Checkpoints

Condition Hierarchy (Ancestors)

Brain Damage, Chronic; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases

Intervention Hierarchy (Ancestors)

Motor Activity; Movement; Musculoskeletal Physiological Phenomena; Musculoskeletal and Neural Physiological Phenomena; Cell Cycle Checkpoints; Cell Cycle; Cell Physiological Phenomena; G2 Phase; Interphase

Study Officials

• Andreas Habersack, BSc MSc

  Medical University of Graz

  PRINCIPAL INVESTIGATOR

• Martin Svehlik, MD PhD

  Medical University of Graz

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: February 14, 2022
• First Posted: March 8, 2022
• Study Start: June 17, 2022
• Primary Completion: September 30, 2024
• Study Completion: September 30, 2025
• Last Updated: April 2, 2026

Record last verified: 2025-10

Data Sharing

• IPD Sharing: Will not share

Locations

AU (1)