Radiofrequency Treatment

Radiofrequency Ablation (RFA) is a minimally invasive procedure designed to reduce chronic pain by disrupting nerve signals responsible for transmitting pain sensations to the brain. This technique is commonly employed to address pain in the neck, back, joints and nerves affected by pain. ​ 

How Does RFA Work?

RFA uses electrical energy to generate radio waves to generate heat and/or stimulations of specific nerve tissues. Heat (usually around 80 degrees) creates a lesion on the nerve, effectively blocking its ability to send pain signals to the brain. The procedure targets nerves identified as contributors to chronic pain, thereby providing relief. ​ 

Types of Radiofrequency Treatments

  1. Conventional (Thermal) RFA: This method heats the nerve tissue to approximately 80°C, leading to coagulation, destruction and disruption of nerve function. It is often used for conditions like facet joint pain and can provide pain relief lasting from 6 months to 2 years. ​However, the destruction of the nerve limits its use as nerves that have a motor (movement) function cannot be treated this way. There is also a risk of a significant flare of pain after the procedure.

  2. Pulsed Radiofrequency (PRF): In PRF, an electrical field is applied in short bursts at a lower temperature (around 42°C). This means that is modifies nerve function without causing significant tissue damage. PRF is typically used for any nerve-related pain and can offer long-term relief without affecting normal nerve sensations. ​It can have a shorter duration than thermal RF (6-9 months +/-) but is much safer.

At Nexus pain we prefer to use PRF where possible. This is due to the fact we prefer to avoid tissue damage and promote healing wherever possible. However, there is always potentially an exception to the rule and if you have a preference this is best discussed with your doctor. 

PRF Mechanism of Action:

The exact mechanisms by which PRF alleviates pain are not fully understood; however, several hypotheses have emerged from scientific studies:​

  1. Modulation of Pain Pathways: PRF may influence both central and peripheral pain pathways, altering synaptic transmission and reducing pain perception (Sam et al, 2021)

  2. Reduction of Inflammatory Mediators: Exposure to PRF has been associated with decreased levels of pro-inflammatory cytokines, such as tumour necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6), which are involved in the sensitization of nociceptors and the maintenance of chronic pain states. (Ramzy et al 2018, Lee et al, 2015)

  3. Neural Membrane Stabilisation: PRF may induce changes in the expression of ion channels on neuronal membranes, leading to stabilization of ectopic discharges that contribute to neuropathic pain (Sam et al, 2021). 

  4. Activation of Descending Inhibitory Pathways: There is evidence to suggest that PRF can activate descending inhibitory pain pathways, enhancing endogenous pain control mechanisms ​(Hagiwara et al, 2012)

Radiofrequency treatment has been shown to provide benefit in:

  • Neck and back pain, including sacroiliac joint (particularly relating to facet join pain)

  • Osteoarthritis and other joint pains (including knee, shoulder, hip, spinal facet joints)

  • Neuropathic pain affecting any peripheral nerve 

Safety Profile:

PRF is generally considered safe, with a much lower risk of complications compared to thermal radiofrequency ablation. The non-destructive nature of PRF minimises the likelihood nerve damage, pain and weakness. Transient side effects may include localized pain or discomfort at the treatment site, which typically resolves within a few days.

Procedure Overview

The RFA procedure typically involves the following steps

  1. Preparation: The patient is positioned comfortably, and the skin over the treatment area is cleaned and numbed with a local anesthetic.​

  2. Needle Insertion: Using ultrasound imaging guidance, the doctor inserts a needle into the area near the targeted nerve 

  3. Stimulation Testing: A mild electrical current is passed through the needle to confirm proximity to the target nerve, which may produce a tingling sensation or muscle twitch.

  4. Treatment: Once proper positioning is confirmed, radiofrequency energy is applied to heat the nerve tissue. This takes between about 2-6 minutes per site, depending on what and how the nerve is being treated 

  5. Completion: The needle is removed, and a small bandage is applied to the insertion site.​

Expected Outcomes

The effectiveness of RFA varies among individuals. Overall, I find the response rate in the 40-70% range. For most patients it will take 2-6 weeks after the procedure for the improvement to become evident. The duration of relief can range from several months to over a year, depending on the specific condition treated and individual patient factors. It's important to note that nerves will regenerate over time, which may lead to the return of pain, necessitating repeat procedures. At Nexus pain we will often try to combine treatments to produce long term healing and resolution of symptoms. However, the nature of radiofrequency treatment is that any beneficial effect will eventually wear off (hopefully many months later). If very effective the procedure can be repeated if required.​

Potential Risks and Side Effects

While PRF is generally safe, potential risks include:​ 

  • Temporary increase in pain or discomfort at the treatment site. 

  • Bruising or swelling at the needle insertion site.​ 

  • Infection or bleeding, though these are rare.​

  • Nerve damage leading to numbness or weakness, which is uncommon.​

Post-Procedure Care

After PRF, patients are typically observed for a short period before being discharged. It's advisable to have someone drive you home. Most individuals can resume normal activities within a day or two. Some soreness at the treatment site is normal and can be managed with over-the-counter pain relievers and ice packs. ​

Conclusion

Radiofrequency Ablation offers a viable option for managing chronic pain when standard conservative treatments have failed. By targeting specific nerves responsible for pain transmission, RF treatment can provide significant and lasting relief, improving quality of life and functional abilities. Patients should discuss the potential benefits and risks their doctor to determine if RF treatment is an appropriate treatment them.

REFERENCES

Hagiwara S, Iwasaka  H, Takeshima  N and Noguchi  N. Mechanisms of analgesic action of pulsed radiofrequency on adjuvant-induced pain in the rat: Roles of descending adrenergic and serotonergic systems. 2012. European Journal of Pain. Vol 13(3). Page 249-252. https://doi.org/10.1016/j.ejpain.2008.04.013

Lee JB, Byun JH, Choi IS, Kim Y, Lee JS. The Effect of Pulsed Radiofrequency Applied to the Peripheral Nerve in Chronic Constriction Injury Rat Model. Ann Rehabil Med. 2015 Oct;39(5):667-75. doi: 10.5535/arm.2015.39.5.667. Epub 2015 Oct 26. PMID: 26605164; PMCID: PMC4654073.

Ramzy EA, Khalil KI, Nour EM, Hamed MF, Taha MA. Evaluation of the effect of duration on the efficacy of pulsed radiofrequency in an animal model of neuropathic pain. Pain Physician 2018; 21:191-198

Sam J, Catapano M, Sahni S, Ma F, Abd-Elsayed A and Visnjevac O. Pulsed Radiofrequency in Interventional Pain Management: Cellular and Molecular Mechanisms of Action – An Update and Review. 2021. Pain Physician. 24:525-532 • ISSN 1533-3159. https://www.painphysicianjournal.com/current/pdf?article=NzM2Nw%3D%3D&journal=140