This study is evaluating whether a therapeutic ultrasound device can improve blood flow to the leg with diabetic foot ulcer (DFU).

The VibratoSleeve TUS will be used on to assess its acute vasodilatory and perfusion effects in diabetic subjects with PAD and DFU. Each subject will receive one 90-minute TUS treatment in each of 3 treatment sessions. All post-treatment acute assessments will take place immediately following each day's treatment and no follow-up assessments will be required in this study.

Inclusion Criteria:

1. Presence of at least one DFU (grade 0 or 1 by University of Texas classification)

2. Diagnosis of diabetes mellitus

3. Diagnosis of PAD that meets at least one of the following conditions:

   1. Ankle-brachial index (ABI) of < 0.9 in the same limb as the DFU
   2. Toe Brachial Index (TBI) ≤ 0.6 OR Toe Blood Pressure ≤ 50 mmHg
   3. Documented history of PAD for a minimum of 3 calendar months prior to time of enrollment

4. Aged ≥ 22 years

Exclusion Criteria:

1. Rutherford 6 stage PAD
2. Active DFU infection
3. End-stage renal disease on dialysis
4. HbA1c > 13%.
5. Planned PAD revascularization.
6. Prior stenting in posterior tibial artery.
7. Re-vascularization procedure within 25 days prior to enrollment in the study. (Note: Patients who had re-vascularization procedure earlier than 25 days prior to enrollment are eligible for enrollment if they meet all other criteria).
8. History or diagnosis of severe chronic venous insufficiency or mixed arterio-venous disease.
9. Acute limb ischemia within 30 days prior to treatment.
10. History or diagnosis of deep venous thrombosis below the knee in treatment leg.
11. Any conditions that, in the opinion of the investigator, may render the patient unable to complete the study or lead to difficulties for patient compliance with study requirements, or could confound study data.
12. Patient's enrollment in another investigational study that has not completed the required primary endpoint follow-up period (Note: Patients involved in a long-term surveillance phase of another study are eligible for enrollment in this study).

Collective (analyzed) study data will be published with an exception of discussing an individual subject's outcomes (anonymized) that contribute to a better understanding of the treatment.

Safety surveillance and reporting starts when subject receives therapy with the VibratoSleeve until the end of the final treatment visit. All treatment visits were completed within an average of 1 month per patient.

Although unlikely due to the nature of the device, the following adverse events were reported for each subject through the final treatment visit:

• All device-related adverse events and events for which the relationship to the VibratoSleeve is unknown
• All SAEs Unchanged, chronic, non-worsening or pre-existing conditions are not AEs and should not be reported. Planned hospitalization for a pre-existing condition is not considered a serious adverse event.

Though the treatment device will be known to all participants, the level of treatment will be randomized among 3 distinct sessions and the level of treatment will be masked for the subject (participant), care provider, investigator, and outcomes assessor.