Genicular Nerve Block

Patients with chronic knee pain that has failed to respond to conservative care may be candidates for a genicular nerve block. There are many potential nerves that can transmit the pain signals from the knee, the genicular nerves represent a few of those. A Genicular Nerve Block is performed to ascertain whether or not a person’s chronic knee pain is carried by the genicular nerves.

The patient is on his/her back with the affected knee slightly bent. Sterile soap is used to cleanse the sites for the block. Local anesthetic is then injected through a very small needle to numb the skin where the procedure is going to occur. Three small needles are then placed with live x-ray guidance. Once the needles have been placed in the proper position, a small amount of local anesthetic is injected through each needle to numb the genicular nerves. The needles are then removed and the patient is brought to the recovery area. The local anesthetic that was injected to numb the genicular nerves last for 3 hours. It is VERY IMPORTANT for the patient to pay strict attention to how his/her typical knee pain responded to the injection for the first 3 hours directly following the procedure. The patient should be ACTIVE immediately following the procedure to accurately ascertain the degree of relief he/she is experiencing while the local anesthetic is in effect. If there was significant relief experienced immediately following the nerve block, the patient is likely a candidate for radiofrequency ablation of the genicular nerves at a future visit.

The purpose of doing radiofrequency ablation to the genicular nerves is to provide long-lasting relief for chronic knee pain. A patient who responded with significant short-lived pain relief from the genicular nerve block is most likely a candidate for radiofrequency ablation.

The set-up for the patient is exactly the same as with the genicular nerve block. Special needles are placed after numbing the skin to the same sites with live x-ray guidance. The needles are connected to a machine that will produce heat at the needle tips after the area is numbed. The heat produced by the machine will provide the same degree of relief the patient experienced from the genicular nerve block, with the lasting 6 to 12 months. The procedure takes about 20 minutes to perform. It can take up to ten days to see the effects of the procedure.