Chronic osteoarthritis of the knee is one of the most common conditions as we get older. The knee pain is often not effectively managed with medications or physical therapy. Radiofrequency (RF) neurotomy, when applied to articular nerve branches (genicular nerves), provides a therapeutic alternative for effective management of chronic pain associated with osteoarthritis of the knee.
Although surgery is generally effective for patients with advanced disease, some older individuals with comorbidities may not be appropriate candidates for knee surgery. In addition some patients do not wish to consider surgery and prefer non- surgical options. In these patients, radiofrequency (RF) neurotomy of the genicular nerves of the knee is a successful alternative to surgery. This procedure is based on the theory that cutting the nerve supply to a painful knee joint may alleviate pain and restore function.
Indications for genicular nerve blocks
- Patients with chronic knee pain secondary to osteoarthritis
- Patients with failed knee replacement
- Patients unfit for knee replacement
- Patients who want to avoid surgery
Diagnostic genicular nerve blocks
These injections are performed under fluoroscopy or ultrasound guidance. A small amount of local anesthetic is injected around the superior lateral (SL), superior medial (SM) and the inferior medial (IM) branches, innervating the knee joint. A response is considered positive if there is at least 50% reduction in pain in the 24hrs following injection.
Cooled radiofrequency of genicular nerves
Patients with a positive response to a block are good candidates for COOLIEF* Knee Cooled RF. The procedure is usually done on an outpatient basis. The procedure is performed under fluoroscopic guidance to ensure accuracy of needle placement. Patients need to be aware that the outcome of the procedure is variable and they may not receive the desired benefits. Similarly, they must be aware of the transient nature of the therapeutic benefits and that there may need repeated injections.
Radiofrequency denervation treatment involves creating a heat lesion around the genicular nerves carrying painful impulses from the knee joint. Successful treatment can result in relief of knee pain lasting several months.
Cooled radiofrequency allows creation of larger-volume, spherical lesions compared to conventional radiofrequency. Treatment can take 4 to 6 weeks to work.