The Active Knee Prosthesis Will be Tested to Evaluate How Well it Improves the Gait Symmetry and Reduces the Metabolic Cost of an Amputee During Walking. The Prosthesis Will be Attached to the Socket of the Amputee.
Trial Snapshot
- Phase
- Not Applicable
- Sponsor
- Providence VA Medical Center
- Enrollment
- 10
- Locations
- 2
Study Overview
Brief Summary
The purpose of this study is to develop a robust, low-power, stable, and light weight, active knee prosthetic device that can dramatically increase gait symmetry and walking economy of a transfemoral amputee during walking.
State of the art prosthetic knees can be classified into three main classes: a) mechanically passive, b) variable-damping, and c) powered. Although the devices within each of these classes offer some advantages for above-knee amputees, their overall performance still presents some deficiencies. Artificial knees in the first two groups are predominantly damping devices, incapable of providing positive power output. Moreover, current powered prostheses are heavy and inefficient in their energy consumption, and/or they have a limited range of motion. To overcome such inadequacies, we have designed a novel prosthetic knee device with a biomimetic approach.
The design of the active knee prosthesis is inspired by the antagonistic muscle anatomy of the human knee joint. This device mimics the synergistic muscle activity at the knee using a double series-elastic actuator (SEA) system that resembles the major mono-articular muscle groups that help flex and extend the knee joint. The agonist-antagonist SEA knee architecture will allow for precise force control of the knee joint, mimicking the spring-like behavior of the human knee, as well as providing adequate energy for forward progression of the body. The SEA has been previously developed and tested on legged robots. Also, the SEA has been successfully applied to the development of an actuated ankle-foot orthoses (AAFO) at MIT AI Lab.
The mechanical architecture of the active knee prosthesis allows for independent engagement of flexion and extension tendon-like, series springs for the control of joint position and impedance, as well as net joint torque. Furthermore, this architecture permits a joint rotation with near zero friction, allowing the controller to take advantage of the passive dynamics of the system, thus, augmenting the overall energetic efficiency of the system.
Detailed Description
Healthy participants with above-knee amputations will be recruited. Participants will meet the following eligibility criteria. They will be experienced at prosthesis ambulation, with a capacity of ambulation at least at a K3 level (i.e. having the ability or potential for ambulation with variable cadence). Additionally, amputee participants will be generally healthy and will have no other musculoskeletal problems or any known cardiovascular, pulmonary or neurological disorders.
The research objective is to evaluate the efficacy of an active knee prosthesis that is designed to increase gait symmetry, speed, and to lower metabolic energy demands during walking.
For each amputee participant, a complete study will include three separate experimental sessions conducted in three different locations. These locations are: The Biomechatronics Group, MIT Media Laboratory; the Holodeck room in CSAIL at MIT; and the Indoor Track at MIT's Johnson Athletic Center. The time between experimental sessions will be approximately one to two weeks and the time duration of each session will be two to three hours. For each session, an amputee study participant will be asked to walk at slow, normal, and fast paces for two different conditions. The experimental conditions are:
- Using an assigned commercially, available knee prosthesis (e.g. Otto Bock C-Leg or Ossur Rheo)
- Using the active knee prosthesis
In the first session, each amputee participant will be scheduled to visit the Biomechatronics Group in The MIT Media Laboratory. The main purpose of this session is to qualitatively assess the degree to which the active prosthesis can improve amputee gait. Morphological data (for example, height, weight, limb length and circumference) of the participant will be recorded using the biomechanical data collection form. These data will be used during analysis of data gathered during the gait research sessions.
Study Design
- Study Type
- Interventional
- Allocation
- Na
- Intervention Model
- Single Group
- Primary Purpose
- Diagnostic
- Masking
- None
Eligibility Criteria
- Ages
- 18 Years to 50 Years (Adult)
- Sex
- All
- Accepts Healthy Volunteers
- Yes
Inclusion Criteria
- •They will be experienced at prosthesis ambulation
- •Capacity of ambulation at least at a K3 level (i.e. having the ability or potential for ambulation with variable cadence).
Exclusion Criteria
- •Amputee participants will be generally healthy and will have no other musculoskeletal problems or any known cardiovascular, pulmonary or neurological disorders.
Arms & Interventions
Prosthesis
Motorized External Knee prosthesis for above knee amputees. Comprised of agonist and antagonist actuators to mimic behavior of knee joint during locomotion.
Intervention: Active Knee Prosthesis (Device)