Ultrasonography-Combined with Nerve Stimulator Technique for Injection of the Genitofemoral Nerve in a Patient with Chronic Postoperative Inguinal Pain

ABSTRACT

Chronic postoperative inguinal pain (CPIP) is a major complication after inguinal herniorrhaphy. We report the treatment of CPIP using ultrasonography-combined with nerve stimulator for injection of the genitofemoral nerve (GFN). A 59-year-old man underwent laparoscopic herniorrhaphy and presented with numbness from the inguinal region to the scrotum after operation. In the pain clinic, ultrasonography-guided GFN block and pharmacological treatments had little effect. Six month after operation, patient was referred to the Department of Physical Medicine and Rehabilitation, and ultrasonography-combined with nerve stimulator for GFN injection underwent to enhance the accuracy of neural approach. The induction of scrotal contraction and paresthesia on the GFN distribution was monitored by nerve stimulator and local anesthetic was injected. After the block, pain relief lasted for 6 months without analgesic use. Ultrasonography-combined with nerve stimulator is an effective approach to treat CPIP as it enhances precise localization and injection of small peripheral nerve like GFN.