The purpose of this study is to measure the effectiveness of Sustained Acoustic Medicine (SAM) treatment combined with diclofenac ultrasound coupling gel in patients with stage II and stage III knee osteoarthritis. The ability of the device to reduce pain, increase mobility, increase function of the affected leg, and improve quality of life in patients with knee osteoarthritis will be evaluated.

This is a seven day study to clinically evaluate the effectiveness of the Sustained Acoustic Medicine (SAM) device combined with diclofenac on symptoms of patients suffering from knee osteoarthritis. The class-II device, sam® has been FDA-cleared for home use. On the first day of the study, baseline data will be collected as patients report pain score before treatment. During the following 6 days, patients will self-apply the wearable SAM device with diclofenac patch to their affected knee for 4 hours daily. Each day of the study, pain scores will be recorded immediately before application of SAM device as well as 30 minutes, 2-hours and 4-hours after applying the device. A quality of life and function assessment will be performed prior to the patient beginning the protocol and at the conclusion of the protocol.

Up to 32 subjects will be recruited from neighboring communities to the study sites. The study is designed to reach a target patient population which includes rural citizens and socioeconomic disadvantaged individuals.

Inclusion Criteria:

• Physician-diagnosed mild to moderate knee osteoarthritis (KL Grade 2-3) based on fixed-flexion x-ray radiological findings for osteophytes and joint space narrowing within the past 12 months
• Fulfill the American College of Rheumatology clinical and radiological diagnostic criteria for knee OA
• 45-85 years of age
• Report a frequent pain score between 3-7 (NRS range: 0-10) during the week preceding enrollment
• Report that knee pain negatively affects quality of life
• Willing not to use any cream, gel, or topical solution during the administration of treatment other than the approved ultrasound 1% diclofenac gel provided to the subject at the initiation of the study
• Deemed appropriate by their physician or by the study site physician to participate

Exclusion Criteria:

• Cannot successfully demonstrate the ability to put on and take off the device
• Display any condition which, in the judgment of the investigator, would make participation in the study unacceptable, including, but not limited to, the subject's ability to understand and follow instructions.
• Have severe OA or have little to no cartilage in the knee
• Have knee replacement, other surgical intervention, or hyaluronidase injection in the affected knee in the past 6 months
• Are non-ambulatory
• Participated in a clinical trial for an investigational drug and/or agent within 30 days prior to screening
• Modify their medications during the course of the study (medications and doses must remain constant throughout the study)
• Currently taking steroids
• Have contraindication to radiograph
• Have a secondary cause of arthritis (metabolic or inflammatory)

Through Study Completion, an average of 7 days

The risks associated with this study are minimal. There were no anticipate risk for Serious Adverse Events, risk for All-Cause Mortality or risk for Other (Not Including Serious) Adverse Events.