Case Report: Focused Ultrasound for Facetogenic Low Back Pain


Key Points

  • A 78-year-old male suffered from low back pain for more than six years before focused ultrasound therapy provided relief.
  • The Foundation thanks Christin Tiegs-Heiden, MD, radiologist at Mayo Clinic, for providing this case report.

The Patient
A 78-year-old male initially presented to our clinic approximately six years ago for the evaluation of low back pain. The pain was chronic but had worsened over the past five years. The pain did not radiate into either leg. A physical examination indicated that the pain was originating in the lumbar facet joints. A lumbar magnetic resonance imaging (MRI) showed degenerative facet arthritis with no neural foraminal or central canal stenosis.

The patient attempted to treat the pain with nonsteroidal anti-inflammatory drugs (NSAIDs), but it continued to be severe. Intra-articular steroid injections at L4-5 and L5-S1 provided relief for a few days but had no lasting benefit. Subsequently, after positive comparative medial branch nerve blocks, the patient underwent bilateral L3-4, L4-5, and L5-S1 radiofrequency ablation (Figure 1). These treatments provided approximately one month of relief; however, the pain returned to its baseline. The patient was then referred for MR-guided focused ultrasound (MRgFUS) ablation of the lumbar facet joints.

The MRgFUS Procedure
The patient was directed to lie in a supine position on the MRgFUS table with his lower lumbar spine centered over the Insightec conformal bone transducer (Figure 2).

He was treated with a total of 32 sonications, with energy ranging from 1281-1500 Joules. Sonications were targeted bilaterally to the posterior capsule of the L3-L4 (five sonications per joint), L4-L5 (five sonications per joint), and L5-S1 (six sonications per joint) facet joints (Figure 3).

Moderate sedation was provided throughout the procedure, and the patient tolerated it well. He was observed for approximately one hour after the procedure and then was able to return home.

The MRgFUS procedure provided the patient with nine months of complete relief of his typical low back pain. After nine months, the pain slowly began to return. At 20 months following the initial procedure, the patient returned for a repeat bilateral MRgFUS ablation of the bilateral L3-L4, L4-L5, and L5-S1 facet joints. Prior to the second treatment, he reported his pain level at 8/10. Five days after the second procedure, he reported that his pain was 3/10.

Low back pain is an extremely common problem, affecting nearly 40% of people globally. One common cause of back pain is facet joint arthritis. Therapeutic options include oral medications, physical therapy, intra-articular steroid injections, and radiofrequency ablations. Although these treatments can be beneficial, their effects are usually temporary. No effective surgical treatments exist for facet-mediated pain.

MRgFUS is an emerging alternate therapy for lumbar facet pain. It is being use to ablate the posterior joint capsule of painful facet joints. It is safe and noninvasive.1-2 Selecting appropriate patients with proven facet pain is important to ensure success. To date, a few small, published case reports and series have shown promising results in this patient group.1-2


1. Tiegs-Heiden CA, Lehman VT, Gorny KR, Boon AJ, Hesley GK. Improved Treatment Response Following Magnetic Resonance Imaging-Guided Focused Ultrasound for Lumbar Facet Joint Pain. Mayo Clin Proc Innov Qual Outcomes. 2019 Dec 28;4(1):109-113. doi: 10.1016/j.mayocpiqo.2019.10.003. PMID: 32055777; PMCID: PMC7010965.

2. Weeks EM, Platt MW, Gedroyc W. MRI-guided focused ultrasound (MRgFUS) to treat facet joint osteoarthritis low back pain–case series of an innovative new technique. Eur Radiol. 2012 Dec;22(12):2822-35. doi: 10.1007/s00330-012-2628-6. Epub 2012 Aug 31. PMID: 22935902.

For questions or comments related to this report, please contact Dr. Lauren Powlovich (, the Foundation’s Associate Chief Medical Officer.