Radiofrequency Neurolysis Versus Local Nerve Infiltration in 42 Patients with Refractory Chronic Inguinal Neuralgia

Abstract

Background: Chronic inguinal neuralgia involving ilioinguinal and iliohypogastric nerves is a frequent complication of surgical procedures involving a lower abdominal incision such as hernia repair, appendicitis surgery, or cesarean sections. Chronic inguinal neuralgia is a very painful condition and diagnosis can be challenging as it is an overlooked impairment. Existing specific treatments are inefficient and often fail. Objective: The purposes of this study are to describe, evaluate, and compare ilioinguinal and iliohypogastric radiofrequency neurolysis (RFN) and local injection. Study Design: Retrospective comparison cohort study from 2005 to 2011. Setting: A single center, Academic Interventional Pain Management Unit Methods: Forty-two patients suffering from chronic inguinal pain refractory to specific medication were included. A total of 18 RFN procedures (14 patients) and 28 injections (28 patients) were performed. Pain was assessed in both groups using Visual Analog Scale (VAS) scores (0-10) measured immediately before and after the procedure and at one, 3, 6, 9, and 12 months after the procedure. Mean duration of pain prior to the procedure and mean duration of pain relief were noted. Moreover, mean maximum early pain relief was assessed. All procedures were ambulatory under computed tomography (CT) guidance. Injections contained 1.5 mL of cortivazol and 3 mL of lidocaine-ropivacaine (30%-70%). Radiofrequency neurolysis was performed using a Neurotherm RF Generator. In both cases, 22-gauge needles were used. After needle retrieval, control slices were taken and the patient was supervised for 30 minutes at the CT unit. Results: The mean age in both groups was 48.7 years. Forty-two patients (97.6%) presented postsurgical inguinal pain, 62% of which occurred after hernia repair. All included patients had undergone previously unsuccessful pain therapies. Mean VAS scores were 7.72 in the RF group and 7.46 in the infiltration group. Maximum early pain relief did not statistically differ (77% in the RFN group and 81.5% in the injection group). Mean duration of pain relief was statistically significant (P = .005) in the RF group (12.5 months) compared to the infilitration group (1.6 months). Mean VAS scores during the year following the procedure were all significantly in favor of radiofrequency neurolysis management. Limitations: Those inherent to small study samples and retrospective studies. Conclusion: Radiofrequency neurolysis appears to be significantly more effective than local nerve infiltrations. It is a safe and effective treatment for chronic inguinal pain. Local steroid injection along with local injection of anesthetics should be used as a confirmation of ilioinguinal neuropathy before performing radiofrequency neurolysis. Key words: Radiofrequency, Ilioinguinal, Iliohypogastric, neuropathy, infiltration, computed tomography guidance.