Continuous and Pulsed Radiofrequency for Osteoarthritis Pain in Dogs
Principal Investigator: Jordyn Boesch
DESCRIPTION (provided by applicant):
The IONICRF™ Generator is a radiofrequency (RF) generator used in interventional pain medicine. Specifically, the device is used for continuous radiofrequency (CRF) and pulsed radiofrequency (PRF) of peripheral nerves which transmit nociceptive impulses to the central nervous system. These procedures are routinely performed in people with intractable pain of various etiologies. Radiofrequency cannulas connected to the RF generator are positioned adjacent to peripheral nerves under ultrasonographic guidance, and RF electrodes are fed down the cannulas. CRF heats sensory nerves (e.g., the saphenous nerve innervating part of the canine stifle joint), which are blocked with local anesthetic, to 80°C, creating thermal insult (a process called ‘lesioning’) which induces Wallerian degeneration of the nerve, thereby relieving pain. PRF heats nerves to a lower temperature (~42°C) which produces ultrastructural changes in neurons and may have a neuromodulatory effect. Unlike CRF, PRF does not cause motor deficits, and thus, it can be used on mixed sensory-motor nerves (e.g., the sciatic nerve, which also innervates the canine stifle joint). Combined CRF of the saphenous nerve and PRF of the sciatic nerve might relieve stifle osteoarthritis (OA) pain in dogs that do not respond to currently available treatments or that develop adverse effects on oral medications like non-steroidal anti-inflammatory drugs (NSAIDs). Our group has published pre-clinical proof-of-principle research in healthy beagles that demonstrated that CRF of the saphenous nerve results in moderate to severe Wallerian degeneration and that PRF does not produce light microscopic evidence of nerve damage or decrease conduction velocity. We are currently conducting a pilot clinical trial funded by the G Dog Fund of the effect of combined CRF/PRF on peak vertical force (PVF) using gait analysis in client-owned dogs with intractable stifle OA pain. An older model of this RF generator (the Neurotherm NM1000), which was used in the aforementioned proof-of-principle study, was donated to CUHA by Arnot Medical, Inc. several years ago. It was also used to treat several canine patients in the CUHA that enrolled in our pilot clinical trial. However, during the pilot, this RF generator malfunctioned, could not be repaired by the manufacturer, and must be replaced to continue our research and treat client-owned dogs.