design, prototyping, and testing of a robotic prosthetic leg

Conditions: Amputation; Traumatic, Leg, Lower

Summary: the purpose of this graduate student research study is to test that a specifically designed and novel robotic prosthetic leg (rpl) is feasible, safe and improves symmetry, efficiency, and metabolic function during sit-to-stand and stand-to-sit transitions as compared to the subject's prescribed device, and as compared to no device at all.

phase 2 case study * two subjects will be fitted with a heart rate monitor and with an adapted waist belt with mobile phone attached. * rpl alignment will be verified. * the subjects will use the rpl in parallel bars 10 times and take rests as needed in a chair. * the subjects will perform the timed up and go test (tugt), 10-meter walk test (10mwt), and the 6-minute walk test (6mwt). * the subjects will be fitted with retro-reflective markers. * the subjects will be fitted with a portable oxygen uptake analyzer. * a 4d motion-capture camera system will be used while performing tugt and five times sit to stand (5xsts). * the subjects will perform the above tests in their prescribed daily-wear prosthesis, and then in the rpl. * the subjects will complete the activities-based balance confidence (abc) scale test. * the subjects will be asked a series of open-ended questions regarding the experience, while being audio recorded. phase 3 pilot study * twenty subjects will be randomized into three treatment arms (no prosthesis, prescribed prosthesis, rpl). * the subject will be fitted with a heart rate monitor. * the subject will be fitted with a portable oxygen uptake analyzer. * the subject will be fitted with the rpl, and the alignment of the rpl will be confirmed before testing. * the subject will be fitted with retro-reflective markers. * a 4d motion-capture camera system and force-plate will be used while performing the 5xsts test in the assigned randomized condition. the test will be performed three times in each condition. * the subject will return two more times to complete the tests in the remaining randomized conditions, with a two-week washout period between sessions. * the subject will be given the abc scale test in the beginning and at the end of this study. * the subject will complete the technology attitudes questionnaire (taq). * in total, subject participation will last 1 hour per day, for three sessions, two weeks apart.

Eligibility criteria:
phase 2 inclusion criteria: * unilateral limb-loss. * amputation or knee disarticulation/transfemoral amputation * can walk with a variable cadence (level k3) or play sports (level k4) * uses a prosthesis for walking daily * can stand for 30 seconds on one limb * can follow one-step commands. exclusion criteria: * those who can not walk with a variable cadence (level k1 and k2) * compromised skin on the residual limb (stump) * uncontrolled swelling * missing more than one limb phase 3 inclusion criteria: * unilateral knee disarticulation or transfemoral amputation. * can walk at a single speed (level k2), can walk with a variable cadence (level k3) or play sports (level k4) * can follow one step commands. exclusion criteria: * those who do not use prosthesis for walking (level k1) * compromised skin on the residual limb (stump) * uncontrolled swelling * missing more than one limb