A young male patient developed chronic, severe, and disabling right sided groin pain following resection of his left testicular cancer. Since there is considerable overlap, ultrasound guided, selective diagnostic nerve blocks were done for ilioinguinal, iliohypogastric, and genitofemoral nerves, to determine the involved nerve territory. It was revealed that genitofemoral neuralgia was the likely cause. As a therapeutic procedure, it was injected with local anesthetic and steroid using ultrasound guidance. The initial injection led to pain relief of 3 months. Subsequent blocks reinforced the existing analgesia and were sufficient to allow for maintenance with the use of analgesic medications. This case report describes the successful use of diagnostic selective nerve blocks for the assessment of groin pain, subsequent to which an ultrasound guided therapeutic injection of genitofemoral nerve led to long term pain relief. As a therapeutic procedure, genitofemoral nerve block is done in patients with genitofemoral neuralgia. Ultrasound allows for controlled administration and greatly enhances the technical ability to perform precise localization and injection. There are very few case reports of such a treatment in the published literature. Apart from the case report, we also highlight the relevant anatomy and a brief review of genitofemoral neuralgia and its treatment.
In 1942, Magee described the condition of pain and paresthesias in the distribution of genitofemoral nerve [
Anatomy of nerves around the inguinal region.
A 27-year-old male patient was referred to our pain clinic after having had orchidectomy for a left sided testicular cancer, 2 years earlier. He continued to have a persistent, severe pain in his right groin and scrotal area. The pain was continuous and dull with a heavy feeling. He reported the severity to be 8/10, on average. He described this to be a severe, burning, sharp pain, which could make him nauseous and fainting with any physical activity such as running, jumping, sexual intercourse, and physical examination. He also reported significant sensitivity and allodynia. Prior to our consultation, he was investigated with an ultrasound and CT scan on the right side. Since they showed some signs of edema and possible epididymitis, he was treated with antibiotics, without much improvement. He was also tried on nortriptyline 10 mg and (lyrica) pregabalin 150 mg BID, without much improvement. There were no other comorbidities or allergies. He was referred to us for the possibility of inguinal nerve blocks. On examination, he was anxious and quiet worried. His gait and posture were normal. His scrotal examination showed an empty scrotal sac on the left side and a highly sensitive inguinal region and scrotal sac on the right side. There were no signs of infection, swelling, or redness. There were no signs of inguinal or femoral hernia. The maximum tenderness was found to be just at the pubic tubercle and below, extending up to the whole of the right side of scrotum and also slightly over the medial side of thigh. Since the area of the lower abdomen and groin can be supplied by IL, IH, or GF nerve, we decided to perform separate diagnostic blocks to confirm the diagnosis and for a possible treatment. Initially, he underwent an ultrasound guided IL and IH nerve block, by the corresponding author, using 2 mL of 2% lidocaine and 2 mL of 0.25% bupivacaine mixed with 40 mg of depomedrol. The sensory block achieved did not cover the area of his pain. Approximately a month after that we performed an ultrasound guided GF nerve block using 2 mL of 2% lidocaine and 2 mL of 0.25% bupivacaine mixed with 40 mg of depomedrol.
With patient in supine position, the inguinal area and the area above the femoral vessels were uncovered and wiped with chlorohexidine solution. A high frequency, linear, high resolution probe (GE Ultrasound, LOGIQ e machine) was initially kept perpendicular to the inguinal ligament just above the femoral vessels (Figure
A cephalad movement of the probe identified the iliac artery splitting into femoral and external iliac arteries. This corresponds to the level of the internal inguinal ring [
Visualization of structures in the inguinal canal and transducer orientation.
Injection into the inguinal canal to block the genitofemoral nerve.
Our report demonstrates that an ultrasound guided GF nerve block can be an effective treatment for genitofemoral neuralgia. However, it is critical to identify the involved nerve by performing diagnostic nerve blocks of the inguinal nerves, and the GF nerve to rule out their involvement. Similar to the IL nerve, the genitofemoral nerve arises from L1 and L2 (lumbar segments) and forms a part of the lumbar plexus. It predominantly carries sensory fibres, except the cremasteric motor fibres. The nerve lies on the surface of psoas major muscle, crosses the ureter on its descent, and divides into a genital and a femoral branch at a variable point above the inguinal ligament. The femoral component continues along the femoral sheath. The genital branch, also called the external spermatic nerve, gets into the inguinal canal and lies alongside the spermatic cord (round ligament in females). It carries sensory fibres from the lateral and posterior aspect of scrotum (mons pubis and labium majus in females) [
Most injuries to the GF nerve occur with hernia repair and pelvic surgeries such as urethral sling [
Through this report, we would like to highlight the need for a differential block, a safe and effective diagnosis, possibly leading to long duration of treatment. All these can be achieved using an ultrasound guided procedure.
Written permission from the patient has been obtained for this report.
The author declares that there is no conflict of interests regarding the publication of this paper.