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Dynamic Evaluation of Ankle Joint and Muscle Mechanics in Children With Spastic Equinus Deformity Due to Cerebral Palsy

Not Applicable
Terminated
Conditions
Equinus Deformity
Interventions
Radiation: MRI scanner
Other: Gait analysis
Registration Number
NCT02814786
Lead Sponsor
University Hospital, Brest
Brief Summary

This research will lead to the first evaluation of intrinsic and dynamic joint and muscle mechanics of equinus in cerebral palsy. It would provide a direct cause and effect relationship between equinus and bone deformity. Mechanical insights to the pathophysiology of the targeted muscles will lead to better understanding and, thus, to a better medical and surgical management of equinus deformity. Secondary aim will provide an important insight whether key gait parameters can be exclusively relied upon for surgical treatment planning and evaluation. In a medium-term perspective, depending upon the results of this study, dynamic MRI of the ankle joint may serve as a guiding tool for fixed equinus surgery in case of cerebral palsy.

Detailed Description

Equinus is the most common deformity in children with cerebral palsy. Spastic equinus is typically defined as the inability to dorsa-flex the foot above plantigrade, with the hindfoot in neutral position and the knee in extended position. Approximately 90% of the deformities in cerebral palsy occur in the ankle and foot region alone with the incidence of equinus being around 75%. Spastic equinus exhibits poor muscle control and muscle weakness around ankle and foot, resulting in bone deformities and gait abnormalities. Non-operative conservative management of equinus is typically undertaken up until 8 years in order to prevent recurrent equinus or overcorrection by avoiding high-growth phase of child's development for surgical intervention. Despite these precautions, long term follow-up studies report up to 48% of recurrence rate post-surgery. Recurrence surgery not only increases the economic burden on the society but also has a debilitating impact on children and their families. Previous research is focused on extrinsic risk factors such as CP type, demographic parameters, and clinical gait parameters for surgical recurrence and none assessed the dynamic impact of intrinsic bone deformity on ankle joint and muscle mechanics. A primary reason for this recurrence could be a lack of understanding of bone deformity that might be forcing the child to adapt altered ankle joint and muscle mechanics (bone kinematics, cartilage contact parameters, muscle strain) during dynamic activities. In fact, the surgical treatment of fixed equinus does not consider any bone corrections and focus on muscle release or lengthening only. Being a dynamic pathology, it is critical to understand the in vivo effect of weak ankle joint musculature on joint mechanics and the resultant bone deformity. However, no such efforts have been made so far in the literature. With the advent of technology, researchers have developed and validated dynamic magnetic resonance imaging techniques to analyze in vivo muscle and joint mechanics. Processing this data enables researchers to analytically track bones without having to identify specific points or anatomical landmarks and thus provides the ability to track muscle motion as well as skeletal motion. Thus properties such as bone kinematics, cartilage contact mechanics, musculotendon moment arms, muscle strain and tendon strain are available from these analyses. These techniques can be successfully employed in equinus research to evaluate ankle joint and muscle mechanics in vivo.

Recruitment & Eligibility

Status
TERMINATED
Sex
All
Target Recruitment
24
Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Equinus cohortMRI scanner15 childrens who have a fixed equinus defined as a fixed limitation of dorsiflexion inferior to 0°. Interventions: MRI scanner and gait analysis
Control cohortGait analysisIn this cohort, there will be 15 childrens with age and gender matched to equinus cohort and with no history of lower limb musculo-skeletal injury in past 6 months. Interventions: MRI scanner and gait analysis
Equinus cohortGait analysis15 childrens who have a fixed equinus defined as a fixed limitation of dorsiflexion inferior to 0°. Interventions: MRI scanner and gait analysis
Control cohortMRI scannerIn this cohort, there will be 15 childrens with age and gender matched to equinus cohort and with no history of lower limb musculo-skeletal injury in past 6 months. Interventions: MRI scanner and gait analysis
Primary Outcome Measures
NameTimeMethod
Subtalar joint flexion, pronation, and internal rotationsone year

Subtalar (calcaneus relative to talus) joint rotations and translations will be compared between two cohorts.

Achilles tendon moment arm (MAAT)one year

MAAT is defined as a perpendicular 3D distance between Achilles' tendon line of action and the Medial-lateral Calcaneal axis. Using calcaneal kinematics, MAAT value for each time frame will be quantified and compared between two cohorts.

Talocrural joint flexion, pronation, and internal rotationsOne year

Talocrural (talus relative to tibia) joint rotations and translations will be compared between two cohorts.

Secondary Outcome Measures
NameTimeMethod
Talocrural joint contact areaone year

Joint contact mechanics measures and will be compared between cohorts.

Ankle joint kinematics (joint angles) during walkingone year

Walking gait parameters (ankle, knee, and hip joint angles) will be correlated with primary outcome measures

Subtalar joint contact centroid locationone year

Joint contact mechanics measures and will be compared between cohorts.

Hip joint kinematics (joint angles) during walkingone year

Walking gait parameters (ankle, knee, and hip joint angles) will be correlated with primary outcome measures

Talocrural joint contact centroid locationone year

Joint contact mechanics measures and will be compared between cohorts.

Subtalar joint contact areaone year

Joint contact mechanics measures and will be compared between cohorts.

Knee joint kinematics (joint angles) during walkingone year

Walking gait parameters (ankle, knee, and hip joint angles) will be correlated with primary outcome measures

Trial Locations

Locations (1)

CHRU Brest

🇫🇷

Brest, France

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