Cooled Radiofrequency Ablation May Relieve Chronic Pain after TKA
A minimally invasive ablation procedure offers long-term relief for patients who experience chronic and debilitating pain after total knee arthroplasty (TKA), according to the results of a pilot study presented at RSNA 2021, the annual meeting of the Radiological Society of North America (RSNA).
Between 15% and 30% of TKA patients continue to experience pain and stiffness in the knee after surgery and may require a revision procedure, which may or may not resolve the pain.
A procedure called cooled radiofrequency ablation (C-RFA) may provide pain relief for these patients. An introducer needle is inserted around the knee under local anesthesia to target specific nerve locations. A probe is then guided through the introducer and a low voltage current (radiofrequency) is delivered to the deep sensory nerves around the knee via the probe (Figure 1). Water circulating through the system allows for a greater dissipation of heat from the tip of the probe.
Figure 1. After the introducer needle is placed, the radiofrequency ablation electrode is inserted into the introducer needle. Positioning is verified with imaging.
“With a larger propagating heat wave, you can account for the differences in nerve anatomy from patient to patient because of a larger treatment zone,” said Felix Gonzalez, MD, the study’s lead author and an Assistant Professor in the Division of Musculoskeletal Imaging of the Department of Radiology and Imaging Sciences at Emory University School of Medicine in Atlanta, Georgia. “Treating a larger zone increases the effectiveness of the procedure.”
Building on Prior Research
In previous studies, Dr. Gonzalez’s group showed that C-RFA provides lasting pain relief for people with knee, shoulder, and hip osteoarthritis. [1,2] The new study focused on 21 patients who were experiencing persistent chronic pain after TKA, without underlying hardware complications, and who had all failed conservative care.
The patients filled out clinically validated questionnaires to assess their pain severity, stiffness, functional activities of daily living, and use of pain medication before and after the procedure. Follow-up outcome scores were collected up to 1 year after the C-RFA procedure.
The questionnaire results showed that the patients experienced, on average, a statistically significant improvement in quality of life. Pain and stiffness scores improved dramatically. No major complications were encountered, and no patients required repeat treatment, surgical revision, or other intervention.
“This procedure can have a huge impact in patients who have gone through major surgery and are still suffering pain that is very debilitating,” Dr. Gonzalez said.
Longer-term Pain Relief
The procedure’s long-term relief gives it a major advantage over cortisone injections, which offer, on average, only about 3 months of pain relief in the treatment of knee osteoarthritis.
“It’s very encouraging that up to a year out, these patients have such significant pain relief and a better quality of life,” Dr. Gonzalez said. “The hope is that in that period of time, the patient can become more mobile and increase their activity. Even if pain comes back, we predict that it won’t come back with the same intensity as before.”
Because C-RFA is minimally invasive, it can easily be repeated, Dr. Gonzalez said. It can also reduce or eliminate the use of opioid pain relievers, which carry significant risks associated with dependency.
“We hope that this procedure will become a standard of treatment for pain in this setting,” Dr. Gonzalez said.
Gonzalez F, Khan F, Loya M, Bercu Z, Kokabi N, Tran A, Newsome JM, Reimer NB, Oskouei S, Cristescu M. Management of uncomplicated total knee arthroplasty chronic pain and stiffness utilizing cooled radiofrequency ablation: a single institution pilot study. Presented at RSNA 2021, November 28-December 2, Chicago, Illinois.
Khan FM, Tran A, Wong PK, Aiyedipe S, Loya MF, Cristescu MM, Gonzalez FM. Management of uncomplicated total knee arthroplasty chronic pain and stiffness utilizing cooled radiofrequency ablation: a single institution pilot study. Skeletal Radiol. 2021 Nov 2. doi: 10.1007/s00256-021-03944-z. Online ahead of print.
- Tran A, Reiter D, Wong PK, Fritz J, Cruz AR, Oskouei S, Gonzalez FM. Alternative treatment of hip pain from advanced hip osteoarthritis utilizing cooled radiofrequency ablation: single institution pilot study. Skeletal Radiol. 2021 Oct 5. doi: 10.1007/s00256-021-03927-0. Online ahead of print.
- Wong PK, Kokabi N, Guo Y, Reiter D, Reimer NB, Oskouei S, Gonzalez FM. Safety and efficacy comparison of three- vs four-needle technique in the management of moderate to severe osteoarthritis of the knee using cooled radiofrequency ablation. Skeletal Radiol. 2021 Apr;50(4):739-750. doi: 10.1007/s00256-020-03619-1. Epub 2020 Sep 24.