Amputation Clinical Trials

The purpose of this study is to evaluate the effectiveness of providing sensation of the missing limb to individuals with lower limb loss, including above and below knee amputees. The approach involves delivering small electrical currents directly to remaining nerves via implanted stimulating electrodes. These small electrical currents cause the nerves to generate signals that are then transferred to your brain similar to how information about the foot and lower limb used to be transferred to your brain prior to the amputation. Individuals also have the option to have recording electrodes implanted within muscles of the lower limb(s) in an attempt to develop a motor controller that would enable the user to have intuitive control of a robotic prosthetic leg. Read Less

Our goal is to understand the critical factors associated with outcome acceptance following upper limb loss. We aim to develop a unified theoretical model that describes the psychosocial experience of upper limb prosthesis use and predicts outcome acceptance following upper limb loss. This conceptual framework will enable clinicians and researchers to evaluate and predict patient outcomes following limb loss, and to design interventions that improve outcomes. The proposed two-year study is a mixed methods (qualitative and quantitative) study using an observational design. The qualitative component of the study will involve data collection through telephone interviews with 18 participants and analyses using a grounded theory approach with constant comparison methods. The quantitative component involves administration of standardized measures quantifying constructs of the theoretical model in 120 participants and analyses to produce a structural equation model of outcome acceptance. Participants will include persons with unilateral acquired upper limb loss at the trans radial or trans humeral level who use currently available prosthetic devices. Read Less

The goal of this project is to characterize the types of sensations that can be evoked via electrical stimulation of the spinal cord and spinal nerves. Patients will be recruited from a local pain clinic, each with a spinal cord stimulation device implanted, to participate in experiments to explore the ability to modulate and control the modality, intensity, focality, and location of the sensations evoked by stimulation through the spinal cord stimulator leads. Investigators will connect spinal cord stimulator leads to a custom stimulator system and will ask subjects to report the types of sensations felt. Invesigators will also perform detailed psychophysical metrics to examine participants' ability to discriminate sensations. Read Less

The purpose of this research study is to determine if rifampin, an antibiotic (a medicine that treats infections), is effective in treating osteomyelitis (infection of the bone) of the foot in diabetic patients. Despite use of powerful antibiotics prescribed over a long period of time, many diabetic patients remain at a high risk for needing an amputation of part of the foot or lower leg because the osteomyelitis is not cured. Some small research studies have shown that addition of rifampin to other antibiotics is effective in treating osteomyelitis in both diabetics and non-diabetics. However, because few diabetics with osteomyelitis have been studied, there is no definite proof that it is better than the usual treatments for diabetic patients. If this study finds that adding rifampin to the usual antibiotics prescribed for osteomyelitis reduces the risk for amputations, doctors will be able to more effectively treat many Veteran patients with this serious infection. Improving treatment outcomes is an important healthcare goal of the VA. Read Less

Lower limb amputation is common in the United States, with approximately 150,000 amputations annually. Most individuals walking with a prosthesis demonstrate asymmetrical loading-i.e., they favor the amputated side by placing more weight and increased ground reaction forces through the intact limb-which likely contributes to increased metabolic cost of walking. Lack of adequate muscular strength in the lower limb to attenuate these forces places increased stress on the joints, which may be displaced proximally, and may play a role in reported knee and hip pain in the intact limb. Lower limb muscle weakness following amputation has been well documented. Increasing quadriceps strength is important after an amputation because it is positively correlated with gait speed. Gait speed may also be associated with successful community mobility, which leads to improved quality of life following amputation. Individuals with amputation who resume an active lifestyle are able to maintain strength. However, these individuals represent a minority of persons with lower limb amputation; most individuals report more barriers than motivators to adopt an active lifestyle. Ischemic conditioning (IC) may strengthen leg muscles and reduce the metabolic cost of activity after amputation. In IC, the limb is exposed to brief, repeated bouts of ischemia (reduced blood flow) immediately followed by reperfusion. IC has been shown to improve muscle performance in healthy and diseased populations. IC has also been used more recently in patients with peripheral artery disease (PAD) as an intervention to improve function, such as walking ability. Acute exposure to IC increases muscle strength and activation, both in healthy, active individuals and in those with severe neuromuscular dysfunction, such as stroke survivors. IC also attenuates muscular fatigue. Increased fatigue resistance at submaximal contraction levels following IC may be due to increased neural activation of skeletal muscle. Changes in neural activation of muscle may be particularly beneficial during cortical reorganization after amputation. Reduced quadriceps fatigue during submaximal activities may also drive changes in gait kinematics, such as increased knee flexion during loading and mid-stance. Exposure to IC may also increase the oxidative properties of skeletal muscle, offering a direct pathway to reduce metabolic cost. Therefore, IC may lead to cellular changes that lower the metabolic cost of activity. The primary aim of this study is to quantify the benefits of acute and chronic IC on quadriceps strength and walking economy in individuals with PAD and history of lower limb amputation. Read Less

The purpose of this research study is to see how well a new type of myoelectric prosthesis works. A myoelectric prosthesis is a robotic limb for amputees that is controlled by sensing the activity of muscles in the body above the amputation level. This study involves a medical procedure to implant the Myoelectric Implantable Recording Array (MIRA) in the residual limb. The procedure will be performed under sedation by a physician. When muscles contract, they generate an electrical signal that can be sensed by MIRA and used to control the prosthetic limb. Myoelectric prosthetic limbs normally use electrodes that are placed on the surface of the skin to control different movements. However, MIRA is implanted under the skin, which could improve the ability to control the myoelectric prosthesis. After the MIRA is implanted, training will occur to learn how to control the prosthesis using the muscles in the residual limb. The device can stay implanted for up to one year. The device will be removed (explanted) by a physician. Read Less

Prostheses can be suspended from the amputated limb using a variety of techniques, such as straps and suction. Suspending the prosthesis by creating a vacuum between the prosthetic socket and limb using a pump has benefits over other techniques including improved limb health and mobility. A new pump design will be tested by prosthesis users in the laboratory to verify its functionality during walking. Read Less

The goal of this proposed project is to gather community-based data from the K4-level Transfemoral Amputee (TFA) population to aid in evidence-based prescription of powered prosthetic knees (i.e., choosing the right device to maximize the benefit for each patient). The investigators envision that this Level 1 submission will transition into a larger follow-on Level 2 trial that will explore a larger spectrum of patient populations (K2-K4), as well as testing additional Power Knees currently in development that are expected to become commercialized in the near future. The investigators intend to use this Level 2 trial data to guide the implementation of effective prescriptions towards those that can benefit most from a given device and limit prescription to those who would not see benefit in order to ensure the most judicious use of Department of Defense (DoD) and Veteran's Affairs healthcare dollars. The findings will also be shared with the research community to help drive the design of future devices by identifying what features and functions are most beneficial to which patient populations when the devices are used outside of the laboratory. In summary, more community-based data on how powered prosthetic knees compare with MPKs is needed to allow for improved clinical decision making and clinical outcomes. Read Less

The goal of this proposed project is to gather community-based data from the K2-level Transfemoral Amputee (TFA) population to aid in evidence-based prescription of powered prosthetic knees (i.e., choosing the right device to maximize the benefit for each patient). The investigators intend to use this trial data along with a concurrent study being conducted within the K3-K4 level population to guide the implementation of effective prescriptions towards those that can benefit most from a given device and limit prescription to those who would not see benefit in order to ensure the most judicious use of Department of Defense (DoD) and Veteran's Affairs healthcare dollars. The findings will also be shared with the research community to help drive the design of future devices by identifying what features and functions are most beneficial to which patient populations when the devices are used outside of the laboratory. In summary, more community-based data on how powered prosthetic knees compare with the current standard in TFA populations is needed to allow for improved clinical decision making and clinical outcomes. Read Less

The purpose of this research is to test an investigational fabrication system for transtibial prostheses. This fabrication method will be tested for comfort and function to determine feasibility of use for amputees in developing countries. To address the need for high quality and affordable prosthetic technology in developing countries, the investigators have developed a simplified socket fitting protocol using expandable rigid foam. The foam is formed by mixing small amounts of two liquid components, which typically expands to several times its original volume. Read Less

The investigators propose to evaluate the efficacy of MyoTrain in a prospective clinical study involving 16 individuals with trans-radial upper-limb loss over a period of 206 days. These individuals will be randomized to Group A (Control Group using standard motor imagery training) and Group B (who are provided the MyoTrain system). The investigators will test three hypotheses: The use of MyoTrain results in skills transference to control of the final prosthesis The virtual outcome measures in MyoTrain are correlated with real-world functional outcome measures The use of MyoTrain results in improved clinical outcomes as measured by functional, subjective and usage metrics Following a baseline functional assessment, participants will undergo a 30-day pre-prosthetic training period specific to their assigned Group. After this training period, participants will receive their prosthetic device and occupational therapy consistent with the current clinical care standard, after which they will again undergo clinical assessment. Post-device delivery, participants will then complete 3 56-day blocks of at-home prosthesis use, in between which they will return to clinic for assessment. Read Less

People with lower extremity amputation (LEA) have persistent problems with balance, falls, residual limb pain, functional mobility, cognitive attention during gait, and satisfaction with participation in daily activities, despite using prostheses. The purpose of this randomized clinical trial is to advance understanding of how dynamic foot design features may help people with LEA This study will include people with above-knee amputations, or with bilateral amputations, or with below-knee amputations and lower levels of mobility. The main study questions/goals are: 1a) To determine if frontal plane adaptation in a foot prosthesis impacts performance, comfort, activities of daily living, and community mobility in the study populations. To answer this question, we will compare a locked and unlocked version of the novel prosthesis. 1b) To determine how the unlocked investigational foot condition compares to the person's usual foot using the outcomes listed above. 2) To examine the participants' lived experience during community activities. The study will use performance tests, questionnaires, logbooks, and interviews to monitor person-centered outcomes and perceptions of personal functioning during the use of the investigational foot (locked and unlocked) compared to the person's usual foot. Read Less