Knee ablation, often referred to as Radiofrequency Ablation (RFA), is a minimally invasive treatment designed to manage chronic knee pain, particularly that associated with osteoarthritis. This outpatient procedure involves using controlled heat to disrupt the nerves transmitting pain signals from the knee joint to the brain. This article addresses what patients can realistically expect concerning pain and soreness throughout the knee ablation experience.
Managing Comfort During the Ablation
The patient experience during the knee ablation procedure is carefully managed to minimize acute pain. A local anesthetic, or numbing agent, is administered at the needle insertion sites before the procedure begins. This medication works quickly to numb the skin and underlying tissue, meaning the patient should feel little to no sharp pain as the specialized needle is advanced toward the targeted genicular nerves.
Physicians frequently offer mild oral or intravenous sedation, which helps the patient remain relaxed and comfortable throughout the approximately 30-minute procedure. Before delivering the radiofrequency energy, the medical team must ensure the needle is correctly positioned near the nerve. During this confirmation step, the patient may be asked if they feel a temporary sensation, often described as a brief pressure, tingling, or dull ache, not sharp pain.
The radiofrequency energy is then transmitted through the needle to heat the nerve tissue. This step is often painless because of the local anesthetic already in place. If the patient feels any discomfort, the physician can inject more numbing medication to ensure the treatment area remains fully anesthetized. The goal is to keep the procedure a low-risk, comfortable experience with minimal side effects.
Expectations for Post-Procedure Soreness
Following the procedure, it is common to experience a temporary increase in discomfort, which is different from the chronic pain being treated. This immediate post-procedure pain is typically localized around the needle insertion sites and is often described as a deep bruising, muscle soreness, or a sunburn-like feeling. This soreness is a result of the tissue trauma from the needle insertions and the body’s inflammatory response to the nerve treatment.
The duration of this post-procedure soreness is generally short-lived, typically lasting between three and seven days. In some cases, the discomfort may persist for up to one or two weeks before beginning to subside significantly. Common side effects in the recovery period include minor swelling, bruising, and temporary numbness at the treatment site.
Standard pain management during this recovery phase involves non-prescription medications, such as acetaminophen or ibuprofen, as directed by the physician. Applying ice packs to the area for short intervals, such as 20 minutes at a time, can also help reduce inflammation and soreness. Patients should avoid strenuous activity and submerging the knee in water for the first 24 to 48 hours to promote healing and prevent infection.
Patients should contact their physician if they experience severe pain that is not relieved by medication, a worsening of pain after the first week, or signs of infection such as excessive redness or discharge.
How Nerve Destruction Leads to Relief
The long-term pain relief provided by knee ablation is achieved through the precise application of heat to the genicular nerves surrounding the knee joint. Radiofrequency energy creates a small, controlled thermal lesion on these sensory nerves, effectively interrupting their ability to transmit pain signals. By destroying the targeted nerve tissue, the electrical pathway that sends the sensation of chronic pain from the knee to the brain is blocked.
Maximum pain relief is not always felt immediately because the inflammation and soreness from the procedure must first resolve. While some patients report an immediate reduction in pain due to the anesthetic used, the full therapeutic effect of the nerve destruction may take 10 days to three weeks to become apparent. This delay occurs as the ablated nerve tissue takes time to fully cease function.
The duration of pain relief following knee RFA typically ranges from six to eighteen months. The treated nerves have the ability to regenerate over time, which is why the pain relief is not permanent. When the nerve fully regenerates, the chronic pain signals may return, but the procedure can be safely repeated to provide further periods of relief.