Radiofrequency Denervation
[Article Summary]
Severe knee pain heavily impacts the quality of life for older adults, but not everyone is suitable for or willing to undergo joint replacement surgery. Radiofrequency denervation is a well-established, minimally invasive interventional pain treatment that uses heat to block pain signals. After treatment, about 70% of patients experience a 50% or greater reduction in knee pain, with effects lasting 6 to 12 months. This technique is also applicable to hip and shoulder joint pain.
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A New Way Out for Severe Knee Pain: Understanding Minimally Invasive
Radiofrequency Denervation
With an ageing population, chronic knee pain has become a significant health and social issue. Severe knee pain not only hinders daily activities but also affects social life and overall physical and mental well-being. When pain becomes so severe that it limits mobility, many people consider artificial joint replacement surgery. However, major surgery is not suitable for everyone. For instance, a patient might be too young, have other chronic illnesses that make surgery too risky, or simply be reluctant to have metal implants in their body.
In these situations, patients can consider another minimally invasive option: Radiofrequency Denervation (also known as radiofrequency ablation).
What is Radiofrequency Denervation?
Radiofrequency denervation is a well-established interventional pain treatment. As early as the 1970s, this technique was already being used to treat issues like facet joint pain in the back. Over the past 10 to 20 years, the medical community has further extended its application to treat chronic pain in large joints, particularly knee degeneration.
The areas around our joints are filled with sensory nerves responsible for transmitting pain signals. Taking the knee joint as an example, medical research shows there can be ten or more nerve branches supplying pain sensation to the area. The basic principle of radiofrequency treatment is to specifically target and block these sensory nerves.
During the procedure, the doctor uses real-time medical imaging, such as ultrasound or X-rays, to accurately locate these sensory nerves. Next, a specialised radiofrequency needle is placed next to the nerve and connected to a radiofrequency machine. The machine generates a high-frequency alternating current, using the resulting heat to ablate or ‘’burn‘’ the sensory nerves transmitting the pain. This procedure exclusively targets sensory nerves and does not affect the motor nerves that control muscle movement, so it will not weaken the patient’s mobility.
Treatment Effectiveness and Duration
Medical research and clinical data show that the effects of radiofrequency denervation are highly significant. After completing the treatment, approximately 70% of patients experience a 50% or greater reduction in their knee pain.
Because the ablated nerves will slowly regenerate over time, this pain relief is not permanent. However, it typically lasts for 6 to 12 months, with some patients experiencing improvements for well over a year. This ‘window’ of being pain-free or having reduced pain allows patients to return to their daily lives. It also gives them the ability to undergo physiotherapy to strengthen the muscles surrounding the joint, fundamentally improving joint health.
How to Increase the Success Rate?
To ensure the accuracy and success rate of the treatment, doctors usually perform a ‘diagnostic nerve block’ before the actual radiofrequency ablation.
During this process, the doctor first uses ultrasound or X-rays to locate the target nerves and injects a small amount of local anaesthetic around them. Subsequently, the doctor assesses the degree of pain relief while the anaesthetic is active. If the patient responds well to the anaesthesia (meaning there is a significant drop in pain), it indicates that the true ‘culprit’ causing the pain has been correctly identified. Following this, the success rate of the radiofrequency denervation can reach over 80%.
Beyond the Knee: Hip and Shoulder Applications
In addition to knee pain, radiofrequency denervation technology can also be applied to other large joints in the body. For patients suffering from chronic hip pain or shoulder pain who have not responded to traditional painkillers or injection treatments, this technique offers a new hope for minimally invasive pain relief.
In summary, radiofrequency denervation provides a safe, non-surgical, and effective option for patients plagued by chronic joint pain.
Information provided by Dr. Lee Yuk-ming, Specialist in Pain Medicine
