A Closer Look At Cryosurgery For Neuromas

Marc Katz, DPM

   The truth is that there is a significant learning curve to performing cryosurgery. Many podiatrists are proficient at ankle injections and ankle surgery. They know the anatomy well but would they just pick up a scope and do an ankle arthroscopy without training? I hope not.

   There are techniques and methods that surgeons must follow for optimal results. In the future, continued development of standards and techniques for cryosurgery is essential. More studies would also help to better validate the effectiveness of this technique.

   However, using double-blind studies comparing cryosurgery to traditional excision would not be reasonable. The problem with a comparison is that patients are rarely willing to undergo surgeries for experimental purposes, especially not knowing which procedure they will receive. Also, there is hardly an incision with cryosurgery. So if we did not want the patient to know which procedure we did, we would likely need to make a regular incision in both cases, which is not reasonable. Personally, I rarely do a neuroma excision.

   It is in the practitioner’s best interest to provide patients with alternatives. Traditional nerve excision can cause significant postoperative disability and poorer outcomes than desired. I believe that complications, stump neuroma and poor outcomes are more frequent than previously believed, and are often not reported. A retrospective study looking at interdigital neuroma excision noted greater stump neuroma formation and complications.4 With new devices and better techniques, I believe there can be a resurgence of cryosurgery in the future. There is a need in our profession for other alternatives to traditional nerve removal and since we are the foot experts, we need to start owning alternative procedures such as cryosurgery.

What You Should Know About Ultrasound Guidance

Ultrasound guidance is especially appropriate for guidance of the cryosurgery probe to allow adequate placement onto the affected nerve. For those practitioners who fear they may be freezing other structures and not the nerve, ultrasound is the solution to avoid this problem. I have found the stimulator useful for some nerve ablation areas such as the sural nerve. However, I have found it is not accurate for interspace neuromas because it is difficult to assess patients’ response while they are having pain. The foot is especially sensitive in this area.

   For many years, I have used ultrasound guidance instead of the nerve stimulator for excellent results. The trend in other specialties for nerve cryoablation is ultrasound guidance as well.3 In my experience, I feel this is the only way one should perform cryosurgery. I often hear from other podiatrists who explain that they have no need for ultrasound because of their keen knowledge of foot anatomy. In my experience, the savviest medical specialists use guidance devices regularly instead of leaving their outcome to chance. Localization of the nerve is quicker, more accurate and safer, resulting in quicker onset of anesthesia.

   One example is the use of ultrasound guidance for popliteal nerve blocks.5 The anatomy is known yet clinicians are using ultrasound guidance for accuracy. In addition, I would argue that there are more than a few incidences of a neuroma being removed with direct visualization only to find from a pathology report that it was not nerve tissue but a blood vessel, fat or tendon. If there can be difficulty in some cases locating the nerve with direct visualization, I would argue that ultrasound is a must for closed procedures. The more we can use technology to our advantage, the better the outcomes.

Add new comment