Two-Year Outcomes of Patients Treated with BVN Ablation for the Relief of Chronic Low Back Pain: Results of the SMART Trial
Presented at SMISS Annual Forum 2018
By Hyun Bae MD
With J. Chi , Z. Moses , M. Krag , P. Nunley , M. Bydon , S. Lavoie , SCOUT Investigators ,
Disclosures: Hyun Bae MD A; Relievant. J. Chi B; K2M, Medtronic., Z. Moses None, M. Krag None, P. Nunley None, M. Bydon None, S. Lavoie None, SCOUT Investigators None,
Thirty percent of Americans have low back pain (LBP) at any given time, leading to approximately 50 million physician visits in the U.S. annually. For patients with chronic low back pain (CLBP), the etiology can be difficult to diagnose and then treat using either current non-surgical therapies, with inherent patient adherence challenges, or surgical interventions, with associated long recovery times. Antonacci et al., following anatomic study, proposed that a portion of pain previously ascribed to the disc actually emanates from the vertebral body endplate nociceptors which communicate to the CNS through the basivertebral nerve (BVN).
To report on the two-year outcome data of the treatment arm patients in the SMART trial, which studied RF BVN ablation to treat CLBP.
A total of 128 patients, from the per-protocol treatment arm of the SMART trial, a double-blind sham-controlled randomized trial, were followed for up to 24 months. ODI and VAS instruments were used to collect patient reported outcomes at baseline, 2 wks., 6 wks., 3 mo., 6 mo., 12 mo., and 24 mo.
ODI and VAS data were available on 106 and 104 patients at 24 months respectively. The mean baseline ODI in the treatment arm was 42.4, decreasing to 22.6 at 12 months and 18.8 at 24 months. The mean baseline VAS in the treatment arm was 6.73, decreasing to 3.96 at 12 months and 3.13 at 24 months. Using a paired t-test comparing the 12 and 24-month VAS observations, the mean score at 24 months was significantly improved compared to 12 months (3.80 vs. 3.13, p=0.004).
The SMART trial demonstrates that BVN ablation is statistically and clinically superior to the sham intervention, and that the degree of ODI improvement is approximately one disability category. Longitudinal follow-up of these patients demonstrates that ablation of the BVN for the relief of CLBP is a durable procedure with continuing improvement in patient reported ODI and VAS scores at up to two years.