Radiofrequency Ablation of Palmar Digital Branches of Ulnar Nerve in a Patient with Ulnar Neuropathy

Abstract

Ulnar Tunnel Syndrome (UTS) is ulnar neuropathy at the wrist or hand typically caused by ganglion cysts, lipomas, wrist or hand compression, carpal bone fractures, carpal tunnel syndrome, or anything else that can impinge on the nerve. The symptoms of UTS can be uncomfortable and debilitating, with numbness and tingling of the 4th and 5th digits being the most common. Weakness of the ulnar portion of the hand can lead to decreased grip strength. UTS is typically managed with conservative treatment including anti-inflammatory oral medications, splinting, physical therapy, activity modification, acupuncture, and stretching. Second line treatment includes corticosteroid injections, although these have shown to have little efficacy. Surgery is also an option but may lead to iatrogenic ramifications. Radiofrequency ablation (RFA) is a treatment modality used for chronic pain, which utilizes heat to target nociceptive fibers. Traditionally, RFA is used in treating cervical and lumbar radiculopathy, but it is less studied in peripheral nerve areas. This case report examines a patient who had clinically significant pain relief after RFA to the palmar digital branches of the ulnar nerve. The patient was 63-year-old male who presented with left ulnar neuropathy that had been ongoing for 3 years. Despite conservative management, his symptoms of pain, paresthesia, and weakness persisted. The patient then elected to have a left cubital tunnel release at the elbow with anterior subcutaneous transposition. The surgery provided relief for three months but then led to worsening contractures and pain in the 4th and 5th digits of the left hand. Due to persistent symptoms after conservative management and surgical intervention, he was referred to interventional pain clinic. A decision was made to trial a digital nerve block of the left medial and lateral digital palmar nerves. Following the nerve block, the patient reported 100% improvement in pain and increased range of motion and function. Four weeks later, the patient returned for a radiofrequency ablation of the same nerves. In the week following the procedure, the patient reported that the pain in the little finger was entirely resolved. While radiofrequency ablation has become increasingly popular for the treatment of chronic back pain, its use in peripheral nerve pain has been limited to case reports and few randomized control trials. This case report highlights the successful use of radiofrequency ablation in the treatment of little finger pain and ulnar neuropathy by targeting the median and lateral branches of the palmar digital nerve.