Skip to main content

Amputation clinical trials at University of California Health

6 in progress, 3 open to eligible people

Showing trials for
  • Biofeedback Retention in Individuals With AKA

    open to eligible people ages 18-70

    More than two million Americans are currently living with a full or partial limb loss, and an additional 185,000 amputations occur each year. The majority of amputations occur in the lower limbs. There are many potential causes for amputation, but the majority can be attributed to vascular diseases, such as diabetes, traumatic injury, and cancer. For these individuals, prosthetic devices play an important role in restoring mobility and enabling them to participate in everyday activities. However, when learning to use these devices, patients often alter their movement patterns to compensate for pain or discomfort, a decreased ability to feel what their prosthetic limb is doing, and/or a fear of falling. By changing their movement patterns, patients will tend to am their intact leg, which has been shown to lead to long-term joint damage and chronic injury. For perspective, 75% of United States veterans living with amputation are diagnosed with a subsequent disease affecting their muscle, bone, and/or joint health. Therefore, therapy sessions, known as gait retraining, are an integral part of teaching prosthesis users to walk in a safe and efficient manner. With recent advances in wearable technology, researchers and therapists have begun exploring the use of biofeedback systems to assist with this retraining. In these systems, wearable sensors are used to measure how the patient is moving in real-time, and can provide information on how much time they spend on each leg and how much each joint moves during walking. Biofeedback refers to the process of communicating the information from these sensors back to the patients instruct them whether they need to change their movements. Previous research has shown that these systems have excellent potential for helping patients with physical disabilities improve their quality of motion. However, relatively little research has explored how well individuals with above-knee leg amputations respond to biofeedback during gait retraining. Importantly, the question of whether the new movement patterns taught using biofeedback will persist after training has finished remains unanswered. Therefore, the primary objective of this research is to determine whether biofeedback is a feasible tool for gait retraining with above-knee prosthesis (including a prosthetic knee, ankle, and foot) users. To answer these questions, forty individuals currently using above-knee prosthetic systems will undergo a single session of biofeedback training. Half of these populations will be from the civilian population, and half will be military veterans. During this training, the biofeedback system will apply short vibrations - similar to those generated by cellphones - to their skin every time that the patient reaches the desired degree of hip rotation during walking. Participants will be instructed to keep increasing their hip motion until they feel a vibration on every step. Before training, they will be instrumented with a wearable motion captures system, pressure sensors embedded in their shoes, and a wearable heart rate monitor. Using these devices, researchers will measure the participants' walking patterns without biofeedback determine their current ability. Once training is complete, their walking patterns will be measured again, first while using the biofeedback system, and then again fifteen minutes and thirty minutes after the biofeedback system has been removed. The data measured during these tests will enable researchers to calculate functional mobility scores that are used to evaluate the quality of a patient's walking, and then compare how these scores change before, during, and after biofeedback training. The knowledge gained through this research constitutes a critical step towards identifying optimal biofeedback strategies for maximizing patient mobility outcomes. The findings will be essential for the development of gait retraining protocols designed to reduce the incidence of chronic injury, and enable patients to achieve their full mobility potential. Building on these results, the next research phase will be to incorporate biofeedback training into a standard six-week gait retraining protocol to evaluate its long-term effectiveness as a rehabilitation tool. Unlike traditional gait retraining, which requires patients to visit clinics in-person for all sessions, the wearable, automated nature of biofeedback training will allow patients to continue gait training from home. This ability will enable patients to continue training activities between sessions, and ultimately may be able to substitute for some in-person visits. This potential for remote therapy has exciting implications for improved access to care for individuals living long distances from their rehabilitation providers, or those suffering from social anxiety, as well as during global health pandemics where in-person visits are difficult.

    at UCSF

  • Cryoanalgesia to Treat Phantom Limb Pain Following Above-Knee Amputation

    open to eligible people ages 18 years and up

    When a limb is severed, pain perceived in the part of the body that no longer exists often develops and is called "phantom limb" pain. Unfortunately, phantom pain goes away in only 16% of afflicted individuals, and there is currently no reliable definitive treatment. The exact reason that phantom limb pain occurs is unclear, but when a nerve is cut-as happens with an amputation-changes occur in the brain and spinal cord that actually increase with worsening phantom pain. These abnormal changes may often be corrected by putting local anesthetic-called a "nerve block"-on the injured nerve, effectively keeping any "bad signals" from reaching the brain with a simultaneous resolution of the phantom limb pain. However, when the nerve block resolves after a few hours, the phantom pain returns. But, this demonstrates that the brain abnormalities-and phantom pain-that occur with an amputation are not necessarily fixed, and may be dependent upon the "bad" signals being sent from the injured nerve(s), suggesting that a very long peripheral nerve block-lasting many months rather than hours-may permanently reverse the abnormal changes in the brain, and provide definitive relief from phantom pain. A prolonged nerve block lasting a few months may be provided by freezing the nerve using a process called "cryoneurolysis". The ultimate objective of the proposed research study is to determine if cryoanalgesia is an effective treatment for intractable post-amputation phantom limb pain. The proposed pilot study will include subjects with an existing above-knee amputation who experience intractable daily phantom limb pain. A single ultrasound-guided treatment of cryoneurolysis (or sham block-determined randomly like a flip of a coin) will be applied to the major nerves of the thigh. Although not required, each subject may return 4-6 months later for the alternative treatment (if the first treatment is sham, then the second treatment would be cryoneurolysis) so that all participants have the option of receiving the active treatment. Subjects will be followed for a total of 12 months with data collected by telephone.

    at UCSD

  • Psilocybin-assisted Therapy for Phantom Limb Pain

    open to eligible people ages 18-75

    This double-blind placebo-controlled pilot study seeks to investigate whether psilocybin can be safely administered to people with chronic phantom limb pain (PLP) in a supportive setting with close follow-up, and its effects on pain symptoms and other moods, attitudes, and behaviors. The investigators' primary hypotheses are that psilocybin is safe to administer in people with PLP and that it will reduce scores on measures of pain. The investigators will also assess a number of secondary measures related to the behavioral and neural responses to pain after psilocybin treatment.

    at UCSD

  • Closed-loop Deep Brain Stimulation to Treat Refractory Neuropathic Pain

    Sorry, in progress, not accepting new patients

    Deep brain stimulation (DBS) holds promise as a new option for patients suffering from treatment-resistant chronic pain, but current technology is unable to reliably achieve long-term pain symptom relief. A "one-size-fits-all" approach of continuous, 24/7 brain stimulation has helped patients with some movement disorders, but the key to reducing pain may be the activation of stimulation only when needed, as this may help keep the brain from adapting to stimulation effects. By expanding the technological capabilities of an investigative brain stimulation device, the investigators will enable the delivery of stimulation only when pain signals in the brain are high, and then test whether this more personalized stimulation leads to reliable symptom relief for chronic pain patients over extended periods of time.

    at UCSF

  • Improving Postamputation Functioning by Decreasing Phantom Pain With Perioperative Continuous Peripheral Nerve Blocks: A Department of Defense Funded Multicenter Study

    Sorry, accepting new patients by invitation only

    When a limb is amputated, pain perceived in the part of the body that no longer exists often develops, called "phantom limb" pain. The exact reason that phantom limb pain occurs is unclear, but when a nerve is cut-as happens with an amputation-changes occur in the brain and spinal cord that are associated with persistent pain. The negative feedback-loop between the injured limb and the brain can be stopped by putting local anesthetic-called a "nerve block"-on the injured nerve, effectively keeping any "bad signals" from reaching the brain. A "continuous peripheral nerve block" (CPNB) is a technique providing pain relief that involves inserting a tiny tube-smaller than a piece of spaghetti-through the skin and next to the target nerve. Local anesthetic is then introduced through the tiny tube, which bathes the nerve in the numbing medicine. This provides a multiple-day block that provides opioid-free pain control with no systemic side effects, and may prevent the destructive feedback loop that results in phantom limb pain following an amputation. We propose a multicenter, randomized, triple-masked (investigators, subjects, statisticians), placebo-controlled, parallel arm, human-subjects clinical trial to determine if a prolonged, high-concentration (dense), perioperative CPNB improves post-amputation physical and emotional functioning while decreasing opioid consumption, primarily by preventing chronic phantom limb pain.

    at UCSD

  • Pulsed Shortwave Therapy for Postoperative Analgesia

    Sorry, accepting new patients by invitation only

    Pulsed shortwave (radiofrequency) therapy is a possible method of pain control involving the application of electromagnetic energy (also termed pulsed electromagnetic fields). Food and Drug Administration-cleared devices have been in clinical use for over 70 years. For decades, available devices consisted of a large signal generator and bulky coil applicator that were not portable and produced significant electromagnetic interference, making them impractical for common use. However, small, lightweight, relatively inexpensive, noninvasive, Food and Drug Administration-cleared devices that function for 8 days are now available to treat acute and chronic pain, decrease inflammation and edema, and hasten wound healing and bone regeneration. Therefore, it has the potential to concurrently improve analgesia and decrease or even negate opioid requirements, only without the limitations of opioids and peripheral nerve blocks. The purpose of this study is to explore the possibility of treating acute postoperative pain with nonthermal, pulsed shortwave (radiofrequency) therapy, optimize the study protocol, and estimate the treatment effect.

    at UCSD

Our lead scientists for Amputation research studies include .

Last updated: