The femoral nerve is located in the leg. It helps the muscles move the hip and straighten the leg. It provides feeling (sensation) to the front of the thigh and part of the lower leg.
A nerve is made up of many fibers, called axons, surrounded by insulation, called the myelin sheath.
Damage to a nerve, such as the femoral nerve, is called mononeuropathy. Mononeuropathy usually means there is a local cause of damage to a single nerve. Disorders that involve the entire body (systemic disorders) can also cause isolated nerve damage (such as occurs with mononeuritis multiplex).
More common causes of femoral nerve dysfunction are:
- Direct injury (trauma)
- Prolonged pressure on the nerve
- Compression or entrapment of the nerve by nearby parts of the body or disease-related structures (such as a tumor or abnormal blood vessel)
Prolonged pressure on the nerve decreases blood flow in the area. This can lead to further complications.
The femoral nerve can be also be damaged if you have:
- A broken pelvis bone
- A catheter placed into the femoral artery in the groin
- Diabetes, which can cause widespread nerve damage
- Internal bleeding in the pelvis or belly area (abdomen)
One common risk factor is lying on the back with the thighs and legs flexed and turned ("lithotomy" position) during surgery or diagnostic procedures. Branches of the femoral nerve can be compressed by tight or heavy waist belts. People who lose or gain a lot of weight may be at greater risk of femoral nerve injury. Also, people who have more widespread nerve damage from medical or hereditary causes may be more prone to injury to the femoral nerve with any pressure. In some cases, no cause can be found.