What is radio frequency?

 

Radio frequency is an analgesic procedure that aims to reduce or alleviate pain through a physiologically acceptable alternating current that heats the periphery of the affected nerve, thereby creating a lesion and restricting the transmission of pain signals. This technique has been used for many years and is increasingly prescribed by doctors due to its improved effectiveness and safety.

The procedure uses a cannula with a conductive active tip combined with a thermocouple electrode. A high-frequency alternating current (500 kHz) is passed through the electrode. The tip (2 -10 mm), which is in contact with the target nerve, heats the tissue and creates a lesion. This allows the therapeutic action to take effect. For added safety, the temperature must always be controlled, either automatically or manually.

Radio frequency generator and cannula

 

Types of radio frequency:

 

There are currently two types of radio frequency: conventional radio frequency (RF) and pulsed radio frequency (PRF).

Conventional or thermal radio frequency (RF) is a neuroablative technique that uses heat energy to interrupt the nerve transmission of pain signals caused by an injury. A high-frequency, low-energy current (500 kHz) is passed through the cannula which interrupts pain transmission by creating a precise burn (thermocoagulation) at 80°C, which limits the sensory response of the affected nerve.

Unlike conventional radio frequency, pulsed radio frequency (PRF) is a neuromodulation technique which applies the current in pulses or intervals. By interrupting the alternating current, it is possible to control the temperature and prevent the heat generated in the tissue from causing any irreversible thermal lesions. In this type of radio frequency, the maximum temperature reached is 42°C using lesion times of 2-8 minutes. As it is non-destructive, this technique is indicated in cases of neuropathic pain or when conventional RF cannot be used.

 

What type of pain can be treated with radio frequency1?  

 

  • Facet joint pain (vertebral joints)
  • Pain due to osteoarthritis of the hip, knee and shoulder
  • Spinal column pain: cervical, lumbar, vertebral lesions, dorsal, and arthritis symptoms
  • Post-surgical pain (after spinal surgery or painful scars)
  • Discogenic pain: herniated disc with radiculopathy or pure discogenic pain
  • Certain cases of migraine (cervicogenic)
  • Sacroiliac joint pain
  • Peripheral nerve pain: ribs, suprascapular, pudendal nerve, abdominal pain, etc.
  • Complex regional pain and phantom nerve pain

 

What are the side effects of radio frequency?

 

Radio frequency has very few side effects provided that the technique is performed by a specialist in accordance with the established safety guidelines and protocols. The procedure must be performed in an operating room to ensure aseptic conditions. As this is physical technique, there are certain side effects caused by the infiltration, including mild discomfort. However, the side effects are minimal due to the use of local anaesthesia and sedation. Bruising may appear if the cannula is not inserted correctly or if it hits a capillary or large blood vessel. However, the bruising should subside within a few days.

Dr Juan Perez-Cajaraville, Coordinator of the Pain Unit for the HM Hospital Group, explains the use of radio frequency to alleviate pain in the following video:

 

 

Equipment required to perform the technique

 

The following equipment is needed to perform the technique:

  • Radio frequency generator: This generator lets the specialist monitor the temperature of the electrodes and continuously measure the impedance.

 

 

  • Radio frequency cannulas: the cannulas are designed for easy and accurate placement on the target nerve. They are positioned percutaneously next to an electrode to deliver RF energy to the target tissue and to measure its temperature. The cannulas are usually insulated and are narrower at the tip to facilitate insertion and manoeuvrability.
  • Dispersion plate: this is needed to be able use the RF equipment with the cannulas as it completes the electrical circuit and lets the alternating current disperse through a ground connection.

 

If you would like to know more about radio frequency products, specifications, and references, please visit the Cardiva website. For more information, please contact us via the following link: https://www.cardiva.com/contacto/