Peripheral nerve stimulation - Our experiences with the wireless high-frequency system.

Introduction: Peripheral nerve stimulation using a wireless high-frequency system offers an alternative to neurostimulator implantation. This approach has the potential to reduce the treatment's risk profile and improve overall quality of life. Methods: Between January 2021 and October 2024, 21 patients were treated at our clinic using a wireless high-frequency system for peripheral nerve stimulation (PNS). The system was implanted under local anesthesia via a Tuohy needle puncture, with ultrasound guidance. The mean surgical time was 36 min (range 16 - 60 min). All patients presented with long history of chronic pain syndromes (mean 49 months, range 8-96 months) and had previously undergone multimodal pain therapy in specialized centers. The most common causes of pain were patients after traumatic peripheral nerve surgery (n = 10, 47.7%) followed by pain after previous surgeries (n = 8, 38.1%) and 3 patients (14.1%) with peripheral nerve tumors. The most common nerve targeted for stimulation was ulnar nerve (n = 7, 33.3%), followed by peroneal nerve (n = 4, 19%), tibial nerve (n = 3, 14.3%), median nerve (n = 3, 14.3%), occipital nerve (n = 2, 9.5%), infrapatellar nerve (n = 1, 4.8%) and medial antebrachii cutaneous nerve (n = 1, 4.8%). All patients reported preoperative neuropathic pain, with NRS (Numeric Rating Scale) scores ranging from 7/10 to 10/10 (mean 8.2/10). Results: Pain reduction was achieved in 17 (81%) patients, with NRS scores decreasing from 8.2/10 preoperatively to 4.3/10 postoperatively (mean reduction of 5.2/10). Additionally, 14 (66.7%) patients experienced a reduction in their pain medication use, with some patients completely discontinuing their medication.However, no positive effects were observed in the patient receiving median nerve stimulation due to a tumor and previous fascicle biopsy, nor in the two patients with a history of lacerations and partial nerve transplants, despite correct pain area coverage.19 (90.5%) patients would choose peripheral nerve stimulation again.In most patients (94%, n = 16/17), stimulation was applied twice daily for 30 min. Additionally, 7/17 (41.2%) patients used the system to manage acute pain attacks. No infections, wound healing or other complications were reported in any patient. Conclusion: Peripheral wireless high frequency stimulation is a simple and feasible option for patients with chronic pain syndrome within the territory of a specific peripheral nerve. In patients with prior partial nerve grafting, seems to be the introduced system less effective, despite correct coverage of the pain area.