The femoral nerve is a

nerve A nerve is an enclosed, cable-like bundle of nerve fibers (called axons). Nerves have historically been considered the basic units of the peripheral nervous system. A nerve provides a common pathway for the Electrochemistry, electrochemical nerv ...

in the thigh that supplies skin on the upper thigh and inner leg, and the muscles that extend the knee. It is the largest branch of the lumbar plexus.

Structure

The femoral nerve is the major nerve supplying the anterior compartment of the thigh. It is the largest branch of the lumbar plexus, and arises from the dorsal divisions of the ventral rami of the second, third, and fourth lumbar nerves (L2, L3, and L4). The nerve enters Scarpa's triangle by passing beneath the

inguinal ligament The inguinal ligament (), also known as Poupart's ligament or groin ligament, is a band running from the pubic tubercle to the anterior superior iliac spine. It forms the base of the inguinal canal through which an indirect inguinal hernia may ...

, just lateral to the

femoral artery The femoral artery is a large artery in the thigh and the main arterial supply to the thigh and leg. The femoral artery gives off the deep femoral artery and descends along the anteromedial part of the thigh in the femoral triangle. It enters ...

. In the thigh, the nerve lies in a groove between iliacus muscle and psoas major muscle, outside the femoral sheath, and lateral to the femoral artery. After a short course of about 4 cm in the thigh, the nerve is divided into anterior and posterior divisions, separated by lateral femoral circumflex artery. The branches are shown below:

Muscular branches

* The nerve to the pectineus muscle arises immediately above the inguinal ligament from the medial side of the femoral nerve, and passes behind the femoral sheath to enter the anterior surface of the muscle. * Anterior division supplies the sartorius muscle * Posterior division supplies the rectus femoris muscle, the three vastus muscles – ( vastus medialis, vastus lateralis, and vastus intermedius), and the articularis genus muscle. The articularis genus is supplied by a branch of the nerve to vastus intermedius.

Cutaneous branches

* The anterior division gives off anterior cutaneous branches: The anterior cutaneous branches are: the intermediate femoral cutaneous nerve and the medial femoral cutaneous nerve. * The posterior division gives off only one branch, which is the saphenous nerve.

Articular branches

* Hip joint is supplied by the nerve to the rectus femoris. * Knee joint is supplied by the nerves to the three vastus muscles. The nerve to vastus medialis is particularly thick because it contains the proprioceptive fibres from the knee joint. This is in accordance to the Hilton's law.

Vascular branches

* Branches to the femoral artery and its branches.

Clinical significance

Signals from the femoral nerve and its branches can be blocked to interrupt the transmission of pain signals from the innervation area. Some of the

nerve block Nerve block or regional nerve blockade is any deliberate interruption of signals traveling along a nerve, often for the purpose of pain relief. #Local anesthetic nerve block, Local anesthetic nerve block (sometimes referred to as simply "nerve b ...

s that work by affecting the femoral nerve are the femoral nerve block, the fascia iliac block and the 3-in-1 nerve block. Femoral nerve blocks are very effective. During pelvic

surgery Surgery is a medical specialty that uses manual and instrumental techniques to diagnose or treat pathological conditions (e.g., trauma, disease, injury, malignancy), to alter bodily functions (e.g., malabsorption created by bariatric surgery s ...

and abdominal surgery, the femoral nerve must be identified early on to protect it from iatrogenic nerve injury. The femoral nerve stretch test can be performed to identify the compression of spinal nerve roots. The test is positive if thigh

pain Pain is a distressing feeling often caused by intense or damaging Stimulus (physiology), stimuli. The International Association for the Study of Pain defines pain as "an unpleasant sense, sensory and emotional experience associated with, or res ...

increases.

Additional images

File:Gray546.png, Structures passing behind the right

File:Gray827.png, Nerves of the right leg. File:Slide6888.JPG, Femoral nerve.Deep dissection. File:Slide8AAA.JPG, Femoral nerve.Deep dissection.

References

External links

* * - "Femoral nerve dysfunction" (includes illustration) * - "Posterior Abdominal Wall: Nerves of the Lumbar Plexus" * * *
arteries-nerves%20LE/nerves1
at the Dartmouth Medical School's Department of Anatomy {{Authority control Nerves of the lower limb and lower torso