Knee ablation, also known as genicular nerve radiofrequency ablation, is a minimally invasive treatment for chronic knee pain. This procedure targets specific nerves around the knee that transmit pain signals to the brain. Its primary purpose is to provide lasting pain relief for individuals who have not found sufficient improvement with conservative treatments.
Targeting Knee Pain
Chronic knee pain can arise from various conditions, including osteoarthritis, persistent discomfort following knee surgery, or other degenerative joint diseases. This pain is often conveyed by genicular nerves, a network of sensory nerves located around the knee joint. These nerves are responsible for sending pain signals from the knee to the brain.
Knee ablation specifically targets these genicular nerves. By disrupting their ability to transmit signals, the procedure reduces the pain messages reaching the brain. This interruption of nerve pathways can lead to a significant reduction in pain.
The Ablation Procedure
Knee ablation is an outpatient procedure. Patients receive a local anesthetic to numb the treatment area, and sometimes a mild sedative for comfort; general anesthesia is not required. The procedure begins with imaging guidance, such as fluoroscopy (live X-ray) or ultrasound, which allows the physician to accurately visualize knee anatomy and precisely locate the genicular nerves.
Once the target nerves are identified, a thin needle, called a cannula, is inserted through the skin and guided to the specific nerve locations. An electrode is then advanced through the cannula, delivering a low radiofrequency current. This energy generates heat, creating a small, localized lesion on the nerve that interrupts its capacity to transmit pain signals. The entire process takes 30 to 60 minutes, and patients can return home the same day.
Determining Candidacy
Knee ablation is considered for individuals with chronic knee pain that has not responded adequately to other conservative treatments. These often include physical therapy, oral medications, and corticosteroid injections. Patients who are not candidates for knee replacement surgery or wish to avoid it may also find this procedure suitable.
A diagnostic nerve block is a key step in determining suitability for knee ablation. During this test, a temporary anesthetic is injected near the genicular nerves to assess pain relief. If a patient experiences at least a 50% reduction in pain for a minimum of 24 hours after the diagnostic block, they are considered a candidate for the full ablation procedure. Factors that might preclude someone include an active infection, certain bleeding disorders, or severe structural joint damage requiring surgical intervention.
Before and After the Procedure
Before knee ablation, patients receive instructions to prepare for the procedure. This may include fasting, adjusting medications like blood thinners, and arranging for transportation home, as driving is not permitted immediately afterward. Wearing loose, comfortable clothing is also recommended.
Following the procedure, patients may experience mild soreness or bruising at the needle insertion sites. Pain relief may not be immediate and can develop gradually over several days or weeks as the treated nerves respond. Most individuals can resume light daily activities within 24 hours, though strenuous activity should be avoided for a short period.
The pain relief from knee ablation is temporary, often lasting between 6 to 18 months, and sometimes up to two years. The treated nerves can eventually regenerate, and if pain returns, the procedure can be safely repeated. Potential mild side effects can include temporary numbness or increased localized soreness.