1 A ligand is any molecule that binds to a specific site on a protein or other molecule. In this case, the estrogen hormone 17-beta-estradiol is the ligand, and the estrogen receptor is the protein.  Binding turns on, or activates, a hormone receptor.
A femoral nerve block is a type of regional anesthesia in which the femoral nerve, located in the groin area, is deadened to allow surgery in the leg or knee area.
Back to Top Causes. 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 the nerve damage, although disorders that involve the entire body (systemic disorders) can also cause isolated nerve damage (such as occurs with mononeuritis multiplex).