AmputationQAMPANCT06780943
Quantification of Motor Compensation Following Biomechanical, Proprioceptive and Physiological Alterations Post-lower Limb Amputation.
An observational study of Amputation, run by Centre Hospitalier Universitaire de Nīmes at 1 site in France.
Trial summary
Lower limb amputation causes segmental loss that alters locomotor organization. The human body, designed to function in a multisegmental manner, must adapt to this new configuration where segments are missing, depending on the level of amputation. Read more about this study
- Who is it for?
- Ages 18 to 80 yearsHealthy volunteers can take part
- Conditions the study is for
- Amputation
- What is being tested?
- Biomechanics, Physiological and Proprioceptive
- How many people
- 75 participants
- Where
- 1 siteFrance
- Study dates
- 6 May 2025to 9 Jul 2026
- Phase
- Observational
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 80 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Study population: Person with unilateral transtibial or transfemoral amputation and healthy volunteers for control population.
Who may be able to join
- The patient must have given their free and informed consent and signed the consent form
- The patient must be a member or beneficiary of a health insurance plan
- Persons with unilateral transtibial or transfemoral amputees followed in the MPR department at the Nîmes University Hospital, RRL department, Grau du Roi University Rehabilitation Hospital.
- All etiologies: vascular, traumatic and septic.
- Adapted equipment validated by the rehabilitation doctor.
- Able to walk for 5 minutes on a treadmill without technical assistance
Show all 9Show fewer
- Adults (>18 years old) and under 40 years old
- Able to walk for 5 minutes on a treadmill without technical assistance.
- Body mass index between 18 and 25
Who cannot join
- The patient is participating in an interventional or a drug/medical device study, or is in a period of exclusion determined by a previous study
- The patient unable to express consent
- It is impossible to give the patient informed information
- The patient is under safeguard of justice or state guardianship
- Patient who has already been included in this study.
- Pregnant, parturient or breastfeeding patient.
Show all 29Show fewer
- Appearance of a stump wound during the study requiring unloading.
- Patient for whom the implementation of vibration stimulation is not possible
- Patient suffering from uncorrected or untreated visual disorders.
- Patient with major cognitive disorders (MoCA <23).
- Patient with vestibular disorders or uncontrolled epilepsy.
- Patient with an unhealed amputation stump.
- Patient with a weight > 135kg or < 20kg
- Patients with a FAC of 1 (i.e. patients who need firm and continuous assistance from a person to support their weight and maintain balance) or less.
- Sensory impairment that makes it impossible to perceive stimulation
- Significantly reduced bone density
- Patient in whom it is impossible to correctly adjust the GRAIL System harness to the corresponding body part due to:
- Body shape
- Colostomy bags
- Skin lesions that cannot be adequately protected.
- Any other reason that prevents a good, painless adjustment of the harness.
- Patient in whom it is impossible to correctly adjust the CON-TREX System:
- Body shape
- Colostomy bags
- Skin lesions that cannot be adequately protected.
- Any other reason that prevents a good, painless adjustment of the support systems.
- History of significant injury or surgery affecting the lower limbs (such as hip or knee replacement or knee/ankle ligament reconstruction) that could impact walking
- History of neurological or psychiatric disorders that could affect locomotion or the processing of sensorimotor information.
- Drug treatments affecting locomotion: drugs likely to alter walking or balance, such as sedatives, muscle relaxants or neuroleptics.
Trial locations and contacts
1 site in 1 country.
About this study
Lower limb amputation causes segmental loss that alters locomotor organization. The human body, designed to function in a multisegmental manner, must adapt to this new configuration where segments are missing, depending on the level of amputation. These adaptations are directly linked to the biomechanical, physiological and proprioceptive alterations caused by the loss of the amputated segments. Without mechanoreceptive afferents essential for regulating locomotion, the sensory system uses alternative information to maintain efficient locomotor function. The prosthesis partially compensates, but remains limited on the biomechanical and proprioceptive levels. Current prosthetic technologies, inspired by biomimicry, aim to imitate evolutionary solutions to restore walking, although current algorithms do not allow real-time modulation. This research aims to characterize post-amputation locomotor adaptations through biomechanical, physiological and proprioceptive exploration to develop a "locomotor characterization" model.
The study authors hypothesize that the post-amputation alterations are exacerbated in contexts of continuous and discontinuous constraints (e.g., ascent/descent and destabilization), and that the addition of a prosthesis, although inspired by biomimicry, only restores partial compensation of locomotor functions.
- Conditions
- Amputation
- Being tested
- Biomechanics, Physiological, Proprioceptive
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
BiomechanicsOther
Amputees and controls will be equipped with measurement sensors to record spatio-temporal, kinetic, kinematic, pressure, electromyographic and physiological parameters of gait in the movement analysis laboratory (GRAIL System).
16 Anatolog FSR sensors will be installed in the amputee population (transtibial, transfemoral on the medial, lateral, anterior and posterior parts of the stump, 4 per side, aligned in the proximal/distal axis. The Anatolog sensors have a sampling frequency of 100Hz. Electromyographic data recording is performed by setting up a number of EMGs depending on the healthy population or the level of amputation. Surface electromyography (sEMG) signals will be recorded from 10 muscles on each lower limb for control subjects and transtibial amputees
PhysiologicalOther
Energy consumption (VO2), will be performed using the VO2 Master Pro (VO2 Master Health Sensors Inc., Vernon, British Columbia, CA). Each participant will wear a face mask connected to the VO2 Master, which will measure oxygen consumption in real time during the assessment. The mask will be adjusted to prevent air leakage and ensure accurate measurements.
ProprioceptiveOther
For amputees, the joint above the amputation will be measured due to the presence of the proximal insertions of the bi-articular muscles and the absence of their distal insertion (i.e., knee joint for transtibial amputees and hip joint for transfemoral amputees).
| Study group | Role | What they receive |
|---|---|---|
| Transtibial amputee patients | Not described Receives: Other: Biomechanics; Other: Physiological; Other: Proprioceptive | |
| Transfemoral amputee patients | Not described Receives: Other: Biomechanics; Other: Physiological; Other: Proprioceptive | |
| Healthy volunteers | Not described Receives: Other: Biomechanics; Other: Physiological; Other: Proprioceptive |
What is being measured
The primary outcome is the main question the study is designed to answer.
Locomotor adaptations induced by amputations on inter-segmental coordination by the evaluation of continuous relative phases under different walking conditions
MARP (Mean Absolute Relative Phase) index of Continuous Relative Phases (movement analysis) where MARP = 0 indicates perfectly synchronization in both segments throughout the gait cycle and elevated MARP indicates poor coordination between the segments
Measured: Day 0
Secondary outcomes (11)
Locomotor adaptations induced by amputations on the impact of locomotor constraints such as inclinations on the explanation of muscular synergies under different walking conditions
Muscle synergy explanation index
Measured: Day 0
Locomotor adaptations induced by amputations on the extent of locomotor constraints such as inclinations on the explanation of muscular synergies under different walking conditions
Number of muscle synergies
Measured: Day 0
Locomotor adaptations induced by amputations on the variability of pressure distributions in the socket under different walking conditions
Variability of pressures in the socket measured with high-pressure Force-Sensing Resistor sensor. The variability will be determined according to the standard deviation of all 16 pressures measured during a walking cycle.
Measured: Day 0
Locomotor adaptations induced by amputations on oxygen consumption under different walking conditions
Average VO2 in the final 30 seconds of walking (mL/mn/kg)
Measured: Day 0
Locomotor adaptations induced by amputations on energy consumption under different walking conditions
Cost of the task defined by the difference in O2 consumption during walking compared to O2 consumption at rest.
Measured: Day 0
Locomotor adaptations induced by amputations on heart rate under different walking conditions
Beats per minute
Measured: Day 0
Characterize the proprioceptive deficits induced by amputations on the angular precision of the joints
Reduction of the angular matching error, where the unilateral angular positioning error is measured as the difference in angular data between the reference angle and the estimated angle
Measured: Day 0
Characterize the proprioceptive deficits induced by amputations on movement perception
Angular displacement detection threshold (°)
Measured: Day 0
Characterize the proprioceptive deficits induced by amputations on response time
Response time for angular matching (ms)
Measured: Day 0
Characterize the proprioceptive deficits induced by amputations on angular displacement
Angular displacement direction detection (%)
Measured: Day 0
Identify a method for restoring proprioceptive deficits via modulation of the "optimal" frequency and amplitude
Proprioception index (average of the different errors and detection thresholds)
Measured: Day 0
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted17 Jan 2025
- Study start6 May 2025
- Primary completion9 Jul 2026
- Study completion9 Jul 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for AmputationStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Case-control
- Time perspective
- Prospective
- Enrolment
- 75 participants (actual)
Sponsor and investigators
- Lead sponsor
- Centre Hospitalier Universitaire de Nīmes
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Eric Pantera, Principal investigator, CHU de Nimes
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06780943
- Sponsor's protocol ID
- LOCAL/2024/EP-02
- Acronym
- QAMPA
- Status last verified
- Oct 2026
- First submitted
- 13 Jan 2025
- Last updated
- 21 Oct 2026
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No