1. Original project aims/objectives: Back pain due to disk-herniation and space-adaptation is a serious concern for the health and wellbeing for astronauts. Current therapeutic drugs and devices to treat space travel related back pain are either systemically and/or cognitively dangerous for mission critical activities, ineffective, and/or non-renewable. The aims of this project were to evaluate long-duration ultrasound therapy as a therapeutic option to non-invasively and non-pharmaceutically effectively treat chronic low-back pain by reducing inflammation, muscle tightness, and modulating neuronal activation at the site of pain. Specifically, the project studied the use of a Food & Drug Administration (FDA)-cleared multi-hour prescription use sustained acoustic medicine device (sam Professional) as a solar-rechargeable therapeutic device to reduce pain, improve range of motion, and increase quality of life for patients with chronic low back pain. Additionally, the project included technology development of other ultrasonic frequencies and device form-factor that could prove useful in the space environment. 2. Key findings: The sam Professional medical device was determined to reduce pain by approximately 2 points on the 0-10 Numeric Rating Scale for patients with moderate to severe low back pain. In 65-subjects meeting study inclusion criteria, back pain was reduced by approximately 30% from baseline when the device was applied 5 times per week over 8 weeks of treatment. Patients in the study reported improved range of motion with less pain, and improved quality of life during daily activities. Analysis of the human subjects' data demonstrated statistically significant (p<0.01) pain reduction for chronic back pain. The multi-hour ultrasound technology was further developed into a coin-sized form factor capable of multi-hour ultrasound delivery, and electronics/transducers were designed and tested for 1 MHz ultrasonic capability. Both clinical and technological project aims and objectives where successfully accomplished. 3. Impact of key findings on hypotheses, technology requirements, objectives and specific aims of the original proposal: The project found that multi-hour daily ultrasound therapy significantly reduced chronic back pain. This clinical study on 55-subjects provides additional clinical efficacy data on managing the symptoms of lower back pain with sam. When combined with other studies on the sam Professional device for back pain (approximately 120 patients in total) the therapeutic intervention is an available non-surgical/non-drug option for back pain patients. The technology is currently available on the US market for prescription use only. Additional electronic testing and validation of the devices would need to be conducted for space deployment. 4. Proposed research plan for the coming year: The project was successfully completed and no additional work is scheduled. The project team anticipates preparation of the key findings for clinical dissemination of the outcome data.