Analysis of the Biomechanical Impact of Lower Limb Length Inequality in PEDiatrics

NCT ID: NCT07254351

Last Updated: 2025-12-04

Basic Information

• Recruitment Status: NOT_YET_RECRUITING
• Total Enrollment: 100 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2025-11-30
• Study Completion Date: 2029-01-30

Brief Summary

Lower limb length discrepancy (LLD) is a frequent condition in pediatric orthopedics. Even moderate discrepancies can induce pelvic obliquity and compensatory scoliosis, modifying the distribution of joint loads at the hips and lumbar spine. These biomechanical imbalances are suspected to contribute to early degenerative conditions such as osteoarthritis or chronic low back pain.

The aim of this study is to quantify the biomechanical impact of LLD in children aged 10 to 15 years, using a combination of low dose biplanar EOS imaging (EOS Imaging System) and synchronized ground reaction force (GRF) measurements from integrated force platforms. These data will be used in musculoskeletal models developed in collaboration with the Biomechanics and Impact Mechanics Laboratory (LBMC, Laboratoire de Biomécanique et Mécanique des Chocs), enabling the estimation of hip joint and lumbar intervertebral disc loads.

This is the first pediatric study integrating EOS imaging, force platforms, and personalized musculoskeletal modeling to explore the mechanical consequences of LLD. The findings are expected to improve clinical reasoning and guide early therapeutic strategies.

Detailed Description

Lower limb length discrepancy (LLD) is a frequent condition in pediatric orthopedics. Even moderate discrepancies can induce pelvic obliquity and compensatory scoliosis, modifying the distribution of joint loads at the hips and lumbar spine. These biomechanical imbalances are suspected to contribute to early degenerative conditions such as osteoarthritis or chronic low back pain.

The aim of this study is to quantify the biomechanical impact of LLD in children aged 10 to 15 years, using a combination of low dose biplanar EOS imaging (EOS Imaging System) and synchronized ground reaction force (GRF) measurements from integrated force platforms. These data will be used in musculoskeletal models developed in collaboration with the Biomechanics and Impact Mechanics Laboratory (LBMC, Laboratoire de Biomécanique et Mécanique des Chocs), enabling the estimation of hip joint and lumbar intervertebral disc loads.

A temporary orthopedic compensation (shoe lift) will also be tested to assess its immediate biomechanical effect. Participants will be evaluated at baseline (two EOS acquisitions: with and without compensation) and at 2 years (without compensation).

This is the first pediatric study integrating EOS imaging, force platforms, and personalized musculoskeletal modeling to explore the mechanical consequences of LLD. The findings are expected to improve clinical reasoning and guide early therapeutic strategies.

Conditions

Lower Limb Length Discrepancy (LLD) in Children

Study Design

• Observational Model Type: COHORT
• Study Time Perspective: PROSPECTIVE

Study Groups

Children with lower limb length discrepancy (LLD)

Pediatric patients aged 10-15 years with an anatomical LLD \> 5 mm, evaluated in the routine pediatric orthopedic care pathway.

EOS Imaging System

Intervention Type: RADIATION

Low-dose biplanar radiographs of the whole body in standing position (EOS Imaging System). At baseline, two EOS acquisitions will be performed in static standing position : one without compensation (natural position) and one with temporary orthopedic compensation (shoe lift under the shorter limb). At 24 months, one EOS acquisition will be performed without compensation. Each acquisition lasts a few seconds, with radiation exposure 5 to 10 times lower than conventional radiographs.

Force Platform (Bertec®, integrated into EOS cabin)

Intervention Type: DEVICE

Ground reaction force (GRF) measurements obtained from a force platform integrated in the EOS cabin. The platform records weight distribution and center of pressure during static standing posture. Measurements are fully synchronized with EOS acquisitions, without additional time or discomfort for participants. At baseline, GRF measurements will be collected in two conditions (with and without orthopedic compensation). At 24 months, GRF measurements will be collected in the non-compensated condition.

Interventions

EOS Imaging System

Low-dose biplanar radiographs of the whole body in standing position (EOS Imaging System). At baseline, two EOS acquisitions will be performed in static standing position : one without compensation (natural position) and one with temporary orthopedic compensation (shoe lift under the shorter limb). At 24 months, one EOS acquisition will be performed without compensation. Each acquisition lasts a few seconds, with radiation exposure 5 to 10 times lower than conventional radiographs.

Intervention Type: RADIATION

Force Platform (Bertec®, integrated into EOS cabin)

Ground reaction force (GRF) measurements obtained from a force platform integrated in the EOS cabin. The platform records weight distribution and center of pressure during static standing posture. Measurements are fully synchronized with EOS acquisitions, without additional time or discomfort for participants. At baseline, GRF measurements will be collected in two conditions (with and without orthopedic compensation). At 24 months, GRF measurements will be collected in the non-compensated condition.

Intervention Type: DEVICE

Eligibility Criteria

Inclusion Criteria

• Children aged 10-15 years
• Anatomical LLD > 5 mm, clinically measured
• EOS imaging indicated by the pediatric orthopedic surgeon in routine care
• Ability to stand still for 30 seconds without assistance
• Covered by social security
• Parental consent and non-opposition obtained

Exclusion Criteria

• - Functional or postural LLD without true anatomical discrepancy
• History of major pelvic or spinal surgery
• Severe neurological or orthopedic condition preventing standing (e.g. cerebral palsy, progressive myopathy)
• Fixed equinus deformity preventing plantar support
• Major lower limb deformity (severe genu varum/valgum)
• Contraindication or inability to undergo EOS imaging

• Minimum Eligible Age: 10 Years
• Maximum Eligible Age: 15 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Hospices Civils de Lyon

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Thierry HAUMONT, MD

Role: PRINCIPAL_INVESTIGATOR

Hospices Civils de Lyon

Central Contacts

Thierry HAUMONT, MD, PhD

Role: CONTACT

thierry.haumont@chu-lyon.fr

4 27 85 57 88 ext. +33

Dimitri HERRERA-NATIVI

Role: CONTACT

dimitri.herrera-nativi01@chu-lyon.fr

Other Identifiers

2025-A01923-46

Identifier Type: OTHER

Identifier Source: secondary_id

69HCL25_0746

Identifier Type: -

Identifier Source: org_study_id