Lower Limb Amputation

The experience of amputation leads to a deterioration in quality of life, with undeniable somatic and functional repercussions. The result is a reduction in general mobility, increased metabolic energy requirements and a feeling of discomfort and pain. The rehabilitation objectives focus on improving, or at least maintaining, the range of movement of the lower limbs, strengthening the overall muscles, ensuring that the equipment is correctly adapted, re-training for physical exertion and working on balance and walking. The rehabilitation objectives focus on social inclusion with the equipment, to optimise the return home and promote social and professional reintegration, and therapeutic education. Factors influencing the postoperative resumption of walking in amputees have been identified as key elements in the success of rehabilitation management. These include maintaining joint range of motion before fitting any equipment, combating postoperative loss of muscle mass, managing cardiorespiratory deconditioning and, finally, resuming walking with the aid of equipment, taking account of fluctuating balance. The literature shows that a change in the centre of gravity and postural instability, particularly when changing stance, are responsible for a greater risk of falls in lower-limb amputees. This asymmetry of gait, which is the cause of a greater risk of secondary joint degeneration, is found in both transtibial and transfemoral amputees. This alteration in balance has a direct influence on walking ability, and therefore calls for significant proprioceptive management in the rehabilitation programme. Gait analysis in lower-limb amputees therefore seems essential, both for the purposes of evaluating and monitoring rehabilitation treatment, and for prosthetic selection and adjustment. Three-dimensional assessment of walking in amputees, coupled with force platforms, is the test of choice for providing kinematic, kinetic and spatiotemporal data (motion capture).

This clinical investigation aims to evaluate a new articulated prosthetic foot during daily-life activities.

Patients with lower limb amputations are equipped with prostheses that can be mechanical and/or electronic. These prostheses can be mono-articular (only the ankle) or bi-articular (knee and ankle for example). For amputee patients, situations that may seem trivial, such as climbing and descending stairs, become complex. Thus during the descent of stairs, an unamputated person will slow down the descent by contracting the thigh muscles, which are obviously lacking in the amputee patient. Current prostheses, known as "intelligent" (or "microprocessor") prostheses, make it possible to adjust the locomotion only once the first step has been taken and to assist the patient during ascent/descent situations on slopes and stairs. The next technological challenge in the development of lower limb equipment is to be able to anticipate these complex environmental situations, in order to secure and facilitate movement even before the obstacle is crossed or the terrain changed. This project plans to use the locomotor expectations commonly made during walking as a means of regulating the locomotor pattern. We believe that these expectations will depend on the situation, i.e. a particular anticipation when climbing or descending a slope, or when approaching a staircase, etc. To understand and describe these locomotor expectations, we plan to use recent techniques called supervised machine learning. These will make it possible to classify locomotor behaviour when walking on a slope or stairs. In the second phase, we would like to describe precisely the characteristics of the movements of the joints, and of the muscles during these adaptations. The final objective of this work is to create an autonomous sensor system to control the anticipatory behaviour of a lower limb prosthesis.

The investigators will assess biomechanical and functional mobility outcomes in individuals with unilateral, above-knee amputations using different knee/ankle configurations of a lightweight powered prosthesis and different volitional controllers in individuals with unilateral, above-knee amputations.

Most of the limb amputation related to vascular disease is often secondary to a diagnosis of type 2 diabetes mellitus. The amputation involves significant motor, psychological, and social challenges for patients, with a major effect on their psycho-physical health. The psychological processes that characterize this clinical population are still poorly investigated. Adopting a biopsychosocial approach, the present randomized prospective quali-quantitative study protocol aims to evaluate the behavioural and psychological adaptation at various stages of the disease: risk of amputation, lower limb amputation, and prosthesis use. In the last phase, patients with prosthesis will receive traditional rehabilitation treatment and technology-based rehabilitation (experimental) or not (active comparator) with randomized controlled enrolment. The evaluation will be based on a semi-structured interview, specific to the disease stage and constructed using the Three Factor Model, and rating scales. Patient's medical history, functional status (ie, motor functionality, autonomy in BIM and FIM, risk of falls, subjective perceived pain), and psychological aspects (ie, emotional impact, HRQoL, anxiety and depression symptoms, personality traits, acceptance, adherence, body image, the experience of the prosthesis and technology-based rehabilitation, expectations for the future) will be investigated. The audio-recorded and transcribed interviews will be analyzed using the Interpretive Description approach.

The purpose of this study is to examine the validity and reliability of the Multidimensional Scale of Perceived Social Support in individuals with lower extremity amputation. Social support plays an important role in psychological well-being, social participation, and adaptation after amputation. However, there is limited evidence regarding whether this scale accurately and consistently measures perceived social support in individuals with lower limb amputation. Participants aged 18 years and older with lower extremity amputation will be invited to complete several questionnaires, including the Multidimensional Scale of Perceived Social Support. Some participants will complete the social support questionnaire a second time within a short period to evaluate the consistency of the results. The findings of this study are expected to contribute to the accurate assessment of perceived social support in individuals with lower limb amputation and to support future clinical and research applications.

This study is a clinical trial that evaluates the best treatment option using a strength training protocol and an endurance training protocol in patients with lower limb amputations who use prostheses. The protocol consists of 6 weeks of strength training and 6 weeks of endurance training, with a 1-month washout period between the two.

Following lower-limb amputation, the loss of somatosensory information from the missing limb renders walking less automatic, more cognitively demanding, and often asymmetric, which can lead to secondary pathologies. Hypothesis: This study is based on the hypothesis that phantom limb sensations (PLS), when coherent with the prosthetic device's movements and the phases of the gait cycle, can compensate for the loss of somatosensory feedback and thereby improve locomotion for individuals with amputation. It is further hypothesized that it is possible to artificially induce these coherent and useful sensations, notably through "referred sensations" elicited by stimulation of the residual limb (e.g., via the prosthetic socket). Objectives: The project aims to: * Determine whether the natural presence of phantom limb sensations during walking impacts gait parameters. * Confirm in a larger patient population that modifications to the prosthetic socket can induce or enhance phantom sensations that are perceived as useful for walking. * Investigate whether these perceptual changes (induced or enhanced) are associated with objective, measurable improvements in gait quality.

The general aim of this exploratory study is therefore to investigate and quantify the functional capacities of patients with lower limb amputations (transtibial and transfemoral), with no change in their management, and to describe any changes in these capacities. The volunteers included in this study will be testing new equipment, all of which will be CE-marked, and will therefore meet all the safety and performance conditions required for use by these patients (equipment that is likely to be prescribed as standard). These devices could benefit from current technological advances that could improve these patients' functional abilities. They will be chosen and adapted according to the volunteer's activity and current equipment. This is a local project of the CHU Dijon Bourgogne which will take place on the Technological Investigation Platform located at the Centre de Rééducation et de Réadaptation of the CHU Dijon Bourgogne. A maximum of 100 patients will take part in the study, divided into two sub-groups of between 5 and 50 patients, depending on the type of brace worn and the level of amputation. After the inclusion visit, each volunteer will undergo 2 assessment visits (the order of assessment of the devices will depend on randomisation) separated by 3 to 6 weeks. Follow-up is for a maximum of 14 weeks.

This prospective randomized controlled study will be conducted to evaluate the analgesic effect of continuous perineural infusion of methylene blue with bupivacaine on acute postoperative pain and to evaluate its preventive role against chronic phantom pain in patients undergoing lower limb amputation surgery