Pulsed Radiofrequency Ablation after One Block for the Treatment of Meralgia Paresthetica

Abstract

Meralgia paresthetica describes a condition in which impingement of the lateral femoral cutaneous nerve (LFCN) causes anterolateral thigh numbness, and often pain. Treatment options include conservative care with nonsteroidal anti-inflammatories, local anesthetic nerve blocks with corticosteroids, radiofrequency ablation of the LFCN, and surgical interventions, such as neurolysis and neurectomy. When a left femoral cutaneous nerve block is used to treat meralgia paresthetica, it is typically repeated before advancing to pulsed radiofrequency ablation (pRFA). We hypothesized that a single trial of a LFCN block, which relieved pain, but for only a short duration was sufficient to advance to pRFA . Our patient was a 55-year-old woman with right anterior lateral thigh pain for 1 year, which made activities of daily living difficult and was resistant to conservative treatment which included nonsteroidal anti-inflammatories, an antidepressant, and an anticonvulsant. Diagnosis of meralgia paresthetica was established by physical exam, nerve conduction study, and electromyography. A LFCN block under ultrasound guidance was successful in resolving 100 percent of the pain for approximately 2 weeks duration, at which time the pain and paresthesia returned to original intensity. The patient was deemed an appropriate candidate for pRFA of the LFCN, which resulted in complete resolution of symptoms as of her 9 month follow-up visit. To our knowledge, this is the first report of the use of pRFA after a single LFCN block providing faster resolution of symptoms and return to activities of daily living. Key words: Pulsed radiofrequency ablation, RFA, pRFA, meralgia paresthetica, lateral femoral cutaneous nerve, LFCN