Lightweight Motorized Prostheses for Lower-limb Amputees
试验速览
- 阶段
- 1 期
- 状态
- 招募中
- 入组人数
- 40
- 试验地点
- 1
- 主要终点
- Prosthesis weight-bearing
研究概览
简要总结
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.
详细描述
AIM1:
For all studies, participants will repeat the same experimental protocol with their passive prostheses and our lightweight powered knee combined with powered, semi-active, and passive ankle. The investigators will also administer a questionnaire based on a 5-point Likert scale to rate intuitiveness, safety, physical demand, and mental demand for each tested condition. Participants will have time to familiarize themselves with the protocol and the prosthesis in a separate training session.
Part 1: Level and Inclined Walking Effort. The study will assess walking effort as participants walk on an instrumented treadmill at their self-selected comfortable speed. The primary outcome of the first study will be residual limb effort measured through peak hip flexion torque on the prosthesis side. Secondary outcomes will include contralateral leg effort, gait symmetry, and balance. The experimental protocol will be repeated for different inclines (e.g., 0%, +/-10%) during separate experimental sessions.
Part 2: Ambulation on Stairs. The study will analyze speed and effort during stair ascent and descent. Participants will ambulate on an instrumented staircase that includes seven steps (four instrumented). The primary outcome for stair ascent will be the ratio between prosthesis work and residual limb work, whereas, for stair descent, the investigators will use sound knee and ankle work. Residual limb, contralateral leg, and upper body effort (handrail force) will be the secondary outcomes, together with subjective preference.
Part 3: Sit-to-Stand Transitions. This study will assess biomechanics as the participant transitions between sitting and standing. Participants will perform sit-to-stand and stand-to-sit transitions from a chair with no armrests at their self-selected pace. The investigators will assess full-body biomechanics similar to our previous sit-to-stand and stand-to-sit studies. The primary outcome of this study will be the degree of asymmetry.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Basic Science
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 80 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Our inclusion criteria will be
- •Above-knee amputation
- •K2/K3/K4 ambulators
- •At least 18 years old
- •At least one year since amputation
- •At least six months since the definitive prosthesis fitting
- •Currently prescribed and using a mechanically passive or microprocessor-controlled prosthesis
排除标准
- •Over 350 lbs. body weight, the weight limit for our safety suspension systems
- •Cognitive deficits or visual impairment that could impair their ability to give informed consent or to follow simple instructions during the experiments
- •Pregnant women due to elevated safety concerns for this population
- •Co-morbidity that limits their ability to participate in the study protocol (e.g., stroke, pacemaker placement that would interfere with the powered prosthesis, severe ischemia, cardiac disease, etc.)
- •Adults who are unable to consent
- •Individuals who are not yet adults (infants, children, teenagers)
- •Individuals who use a wheelchair for mobility both outdoors and indoors because they may not be able to perform the necessary activities with their passive prosthesis or the powered prosthesis
- •Prisoners, due to concerns with informed consent
研究组 & 干预措施
Main Arm
Powered and passive lower limb prosthesis and control
干预措施: Powered and passive lower limb prosthesis and control (Device)
结局指标
主要结局
Prosthesis weight-bearing
时间窗: Baseline and Day 1
Vertical ground reaction force generated by the user on the prosthesis side when standing up and sitting down from a chair.
Amputee Mobility Predictor with Prosthesis (AMPPRO)
时间窗: Baseline and Day 1
The AMPPRO is used to assess functional mobility through a standardized sequence of mobility tests while using a prosthesis. Individual tasks are scored and combined, resulting in a total assessment. The minimum score is zero, and the maximum score on this scale is 47. Higher scores indicate better mobility
Ten-meter walking test
时间窗: Baseline and Day 1
The 10-meter walking test assesses walking speed in meters per second over a short duration.
Ambulation circuit
时间窗: Baseline and Day 1
Average time to complete an ambulation circuit that requires subjects to standup from a chair, walk to a 4-step staircase, climb up the staircase to an elevated platform, continue to walk on the platform, turn, descend an intermediate platform using a two-step staircase, descending a ramp, walking to the chair, and ending by sitting down.
Usability questionnaire
时间窗: Baseline and Day 1
A custom questionnaire based on a 5-point Likert scale to rate intuitiveness, safety, physical demand, and mental demand for each tested condition
Knee torque symmetry
时间窗: Baseline and Day 1
Difference between the knee peak torque on the sound side and on the prosthesis side when the subject climb stairs at different speeds and loading conditions.
Hip torque symmetry
时间窗: Baseline and Day 1
Difference between the hip peak torque on the sound side and on the prosthesis side when the subject walks on inclines at different speeds and loading conditions.
Weight bearing asymmetry
时间窗: Baseline and Day 1
Difference between the vertical ground reaction force on the prosthesis side and the sound side when the subject stands up and sits down from a chair.
Prosthesis to residual-limb work ratio
时间窗: Baseline and Day 1
Ratio between the mechanical work generated by the prosthesis and the residual limb when ascending and descending stairs.
Residual limb effort
时间窗: Baseline and Day 1
Peak hip flexion torque on the prosthesis side when subjects walk at different speeds and inclines.
次要结局
未报告次要终点
研究者
Tommaso Lenzi
Associate Professor
University of Utah