The ilioinguinal nerve is one of a series of nerves that runs throughout the body. It is one of four nerves that make up the lumbar plexus. The lumbar plexus consists of the iliohypogastric, genitofemoral, ilioinguinal and the lateral femoral cutaneous nerves.

The ilioinguinal nerve is located in the lumbar or low back area. It runs from the low back to the abdominal area. This nerve emerges from the spine at the lateral border of the psoas major muscle. The psoas major muscle begins at the first lumbar vertebrae and runs down through the abdomen and attaches on the inside of the femur, or thigh bone. It is responsible for flexion of the hip.

This nerve also crosses two other muscles, the quadrates lumborum and the iliacus. Quadratus lumborum runs from the last lumbar vertebrae to the iliac crest or hip bone, and the sacrum located at the base of the vertebral spine. This muscle elevates the pelvis. The iliacus runs from the iliac crest and sacrum to the inside of the thigh bone where the psoas major attaches. This muscle helps in hip flexion along with the psoas major.

Due to the location of the ilioinguinal nerve problems are not common but can occur. Injury can happen with any type of abdominal surgery. Pain associated with this kind of injury shows up in the inguinal area, which is in the abdomen, and radiated into the legs and genital area.

The ilioinguinal nerve can also become entrapped or compressed through injury. This is when the nerve becomes trapped or restricted commonly due to muscular tension or spasms in the psoas major or iliacus or quadrates lumborum muscles. However, this form of injury is uncommon due to the deep location of this nerve.

Treatment for nerve entrapment includes a nerve block. An ilioinguinal nerve block is an injection of a local anesthetic and steroids. It is a valuable diagnostic and treatment tool when there persistent pain in the abdomen and groin area. This form of treatment is utilized when the pain is thought to be from surgical injury or post-surgical inflammation. It is also used when there is thought to be inflammation or entrapment of the ilioinguinal nerve after a groin injury.

Physical rehabilitation of ilioinguinal nerve entrapment or compression can also consist of a specialized stretching and exercise program designed to release the muscle tightness and spasms of the constricting musculature. Manual techniques, such a psoas release, may also be helpful. This is where a deep pressure is placed on the psoas major muscle to force its release.