Lightning Podiums: Spinal Potpourri - 803B

Presented by: A. Rhyne

Author(s):

A. Rhyne(1), R. Sasso(2), A. Patel(3), W. Hsu(3), J. Fischgrund(4), A. Edidin(5), P. Vajkoczy(6)

(1) OrthoCarolina Spine Center, Charlotte, NC, United States
(2) Indiana Spine Group, Carmel, IN, United States
(3) Northwestern University, Chicago, IL, United States
(4) Beaumont Orthopaedic Center, Royal Oak, MI, United States
(5) Relievant Medsystems, Inc., Sunnyvale, CA, United States
(6) Charité University Medical Centre, Berlin, Germany

Abstract

Introduction: Opioid dependency is a social problem reaching near epidemic proportions in the U.S., with over 20,000 prescription opioid related overdoses observed in 2015.[1] Opioids may be used to manage pain in certain patients diagnosed with chronic low back pain (CLBP); ideally, alleviation of CLBP may affect consumption of opioid pain relievers.

Methods: Opioid use was monitored in a randomized clinical trial (SMART) to investigate the effect of basivertebral nerve (BVN) ablation on CLBP. The primary outcome variable in the trial was the observed change in ODI at 3 months; a statistically significant decrease in ODI was observed in the treatment group.[2] Opioid medication use history was collected at each follow-up interval and subsequently converted to opioid equi-analgesic weekly dose; at each follow-up time point individual use was categorized as unchanged, increased, or decreased. After the conclusion of the study, we compared the average change in ODI and VAS in the treatment group patients who increased as opposed to decreased use of opioid medication at 3 months.

Results: Short acting opioids were used at time of enrollment by 57 out of 145 patients on an intent-to-treat (ITT) basis and 48 out of 127 patients on a per-protocol (PP) basis. At the three month primary endpoint, the mean improvement in ODI and VAS in patients increasing and decreasing their use of opioids was compared. These metrics were statistically and measurably inferior in patients reporting an increased use of opioids as shown in Table 1. Metric ------- Increased OP Use ----- Decreased OP Use --- p-value ODI (ITT) ------ 10.6 ± 8.0 (n=18) ------ 18.7 ± 13.7 (n=29) --- 0.03 ODI (PP) ------ 10.6 ± 9.0 (n=14) ------ 20.9 ± 13.9 (n=24) --- 0.02 VAS (ITT) ----- 0.87 ± 1.5 (n=18) ------ 2.7 ± 2.3 (n=29) ------ 0.004 VAS (PP) ----- 0.80 ± 1.5 (n=14) ------ 3.0 ± 2.2 (n=24) ------ 0.002 Table 1: Comparison of ODI and VAS at 3 months in patients who increased and decreased their use of opioids. Values represent a decrease from baseline.

Discussion and Conclusion: Patients who increased their consumption of opioid medications following RF ablation of the BVN for relief of CLBP had poorer outcomes measured using ODI and less pain relief measured using VAS than did patients with constant or decreasing use of opioids. These data suggest that there exists a relationship between decreased functional and pain outcomes and increased use of opioid pain relievers in patients with CLBP, and that relieving chronic back pain may be a factor in reducing opioid usage. [1] Rudd et al., Increases in Drug and Opioid Involved Overdoses 2010-15, http://dx.doi.org/10.15585/mmwr.mm655051e1 [2] Fischgrund et al., NASS, 2016