Cryoneurolysis for Painful Diabetic Neuropathy of the Foot

The study is a single-center, randomized, participant- and observer-masked, human-subjects, post-market clinical pilot study to investigate the use of ultrasound-guided percutaneous cryoneurolysis to treat diabetic neuropathy of the foot. A prolonged nerve block may be provided by freezing the nerve using a technique called "cryoneurolysis". With cryoneurolysis and ultrasound machines, a small needle-like "probe" may be placed through anesthetized skin and guided to the target nerve to allow freezing. The procedure takes about 6 minutes for each nerve, involves little discomfort, has no systemic side effects, and cannot be misused or become addictive. Participants will be randomly allocated to one of two possible treatments groups: cryoneurolysis (experimental) or sham (control). The primary outcome measure is the change in pain on the neuropathic pain scale from baseline 1 month following the procedure.

The study is a single-center, randomized, participant- and observer-masked, human-subjects, post-market clinical pilot study to investigate the use of ultrasound-guided percutaneous cryoneurolysis to treat diabetic neuropathy of the foot. A prolonged nerve block may be provided by freezing the nerve using a technique called "cryoneurolysis". With cryoneurolysis and ultrasound machines, a small needle-like "probe" may be placed through anesthetized skin and guided to the target nerve to allow freezing. The procedure takes about 6 minutes for each nerve, involves little discomfort, has no systemic side effects, and cannot be misused or become addictive. After 2-3 months, the nerve returns to normal functioning. Participants will be randomly allocated to one of two possible treatments groups: cryoneurolysis (experimental) or sham (control). The primary outcome measure is the change in pain on the neuropathic pain scale from baseline 1 month following the procedure.

Our objective is to investigate the therapeutic benefits of cryoneurolysis for research participants with painful diabetic neuropathy of the feet via a pilot study of 30 research participants. We hypothesize that ultrasound-guided cryoneurolysis of the superficial peroneal nerve will improve pain outcomes in research participants with painful diabetic neuropathy of the foot. The aims of this study will be to:

Primary Specific Aim. Demonstrate the potential efficacy of ultrasound-guided percutaneous cryoneurolysis of the superficial peroneal nerve, sural, distal saphenous, and/or deep peroneal nerve to treat painful diabetic neuropathy of the foot in reducing neuropathic pain 1 month after the procedure compared to baseline. This will be performed as a pilot study and executed as a randomized sham-controlled clinical trial of 30 subjects.

Hypothesis 1: Diabetic neuropathic pain intensity will be decreased relative to baseline 1 month following a cryoneurolysis procedure (as measured by the Neuropathic Pain Scale).

Secondary Specific Aim: To test the influence of a cryoanalgesia treatment as compared to sham/placebo on the long term measurements related to pain, quality of life, and analgesic usage.

Hypothesis 2a: Perception of well-being will be improved 1 month following one cryoneurolysis procedure (as measured with the Patient Global Impression of Change Scale).

Hypothesis 2b: Physical and emotional functioning will be improved relative to baseline 1 month following one cryoneurolysis procedure (as measured with the Interference Subscale of the Brief Pain Inventory).

Hypothesis 2c: Pain and opioid consumption will be reduced in the cryoneurolysis group compare to sham at multiple post-procedure time points, including 1 week, 1 month, 3 months, and 6 months after.

Eligibility Criteria:
Inclusion Criteria:

* Research participants with diabetes mellitus and painful diabetic neuropathy of the foot (unilateral or bilateral)
* HgbA1c \<10 (to avoid any increased risk of site infection)
* Adult patients of at least 18 years of age
* Experiencing at least moderate diabetic neuropathic pain in the foot - defined as 3 or higher on the numeric rating scale (NRS; 0-10, 0=no pain; 10=worse imaginable pain) - at least daily for the previous 2 months.

Exclusion Criteria:

* Diabetic neuropathy not in the distribution of the superficial peroneal nerve, sural nerve, deep peroneal, and/or distal saphenous nerve.
* Comorbidities that are contraindication to cryoneurolysis (e.g., Reynaud syndrome, cryoglobulinemia, cold urticaria)
* Allergy to local anesthetic
* Pregnancy
* Incarceration
* Inability to communicate to investigators due to lack of capacity
* Local infection in the foot/ankle where cryoneurolysis will be performed