It’s a part of the larger structure called the lumbosacral plexus.
The plexus' major function is to supply nerve function to the front part of the thigh.
Structure
The spine is divided up into five sections.
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Even so, the lumbar region is low in your back, where it naturally curves inward.
(The sacral and coccygeal regions below it are short, while the thoracic region is the longest.)
Shortly after exiting the spine, the nerve splits into three parts.
Each part is called a ramus (plural is rami).
Meanwhile, the larger branches continue on, exiting the psoas major muscle through various places.
It gives off branches as it goes.
Most of them have both motor and sensory roles.
There, it divides into its terminal branches.
The iliohypogastric nerve provides motor function to the internal oblique and transversus abdominis muscles.
It provides sensory function to a portion of skin in the pubic region.
Ilioinguinal Nerve
The ilioinguinal nerve has a close relationship with the iliohypogastric.
In women, it innervates the skin over the mons pubis and labia majora.
The femoral branch supplies feeling to the skin on the front of the upper thigh.
The genital branch is mixed, supplying motor function to the cremaster muscle of the scrotum and inguinal canal.
The lateral cutaneous nerve of the thigh is purely a sensory nerve.
It provides feeling to the skin down the front and outer side of the thigh to the knee.
Associated Conditions
A couple of conditions can interfere with the function of the lumbar plexus.
Lumbosacral Plexopathy
Lumbosacral plexopathy is a rare syndrome that affects either the lumbar or sacral plexus.
Symptoms of lumbosacral plexopathy can impact any area innervated by the affected nerves.
In some cases, no cause can be found.
This is called idiopathic plexopathy.
(Idiopathic is the medical term for no known cause.)
It can also be brought on by scoliosis, infection, or, rarely, tumors.
Some people develop radiculopathy due to congenital abnormalities, as well.
Even so, lumbar radiculopathy only accounts for about 3% to 5% of lower back pain diagnoses.
Risk factors for lumbar radiculopathy include repetitive or excessive use of the muscles in the lower back.
It’s most common in people who do heavy labor or play contact sports.
Rehabilitation
The rehabilitation is dependent on the condition that is affecting the function of the lumbar plexus.
Treatment of Lumbosacral Plexopathy
Treatment of lumbosacral plexopathy depends on what’s determined to be the cause.
Unfortunately, no treatment has proven to be consistently effective for diabetic amyotrophy or idiopathic plexopathy.
In diabetics, better control of blood sugar levels is always recommended.
Additionally, a multidisciplinary treatment regimen may include tricyclic antidepressants, anti-seizure medications, physical and occupational therapy.
Treatment of Lumbar Radiculopathy
The treatment of lumbar radiculopathy also depends on the cause.
A herniated disc may be a contributing factor and surgery might be recommended for some patients with chronic pain.
The treatment course is most often conservative and can include:
Less common options include:
Physiopedia.Lumbar plexus.
Teach Me Anatomy.The lumbar plexus.
