You have a femoral nerve catheter, or a nerve block, which is in your groin area. The block sends numbing medicine through a tube to numb the upper thigh and top of the knee. At every shift change, your nurses will check the site and pump settings. The block should decrease the amount of pain you feel and the amount of narcotic pain medicines you need after surgery.

How It Works

The numbing medicine comes in a pump that is programmed to give you the amount of medicine prescribed by your doctor. In most cases, you will receive a small amount of medicine throughout the day. There is a button attached to your pump that you can push to give yourself an extra dose if you need it. Your nurse will explain to you how often you can push the button. This works best for pain on top of the knee.


One main goal of the block is to help you have good pain control while using less narcotic pain medicine. This will help you avoid the bad side effects caused by narcotic pain medicine such as:

  • Low blood pressure

  • Itching

  • Drowsiness

  • Nausea

  • Decreased breathing rate

The Risks

The biggest risk is that a nerve block increases your risk of falling. Even if you have normal feeling in your leg, your muscles are weakened by the medicine. Falls can increase the time of your recovery and can cause injuries. This could require another surgery.

Preventing Falls

There are some important things you can do to reduce your chance of falling.

“Call, don’t fall!”

Remember this phrase while you are in the hospital after your surgery. This is the most important step you can take to prevent a fall. Always call for help before you get out of bed. Having a nurse or nursing assistant with you makes it safer for you to get out of bed.

Use a brace.

A brace, called a knee immobilizer will help prevent your knee from giving out without warning. You will use this brace the entire time you have the block and for several hours after it is removed until your muscle strength returns to normal. Research studies show that using the brace lowers your risk for falling.