156. Pain location and exacerbating activities associated with treatment success following basivertebral nerve ablation: an aggregated cohort study of multicenter prospective clinical trial data

Abstract

BACKGROUND CONTEXT Traditionally, researchers and clinicians have assumed that the vast majority of nociceptive signals intrinsic to the spine have been discogenic. Despite this assumption, ample research demonstrates nociceptive innervation of the vertebral endplate by the basivertebral nerve (BVN). Little is known about the clinically relevant pain loci or specific presenting situations that may predispose individuals to treatment success by BVN radiofrequency ablation. PURPOSE This study presents pain location “maps” and investigates the relationship between low back pain (LBP) exacerbating activities and treatment response to basivertebral nerve radiofrequency ablation (BVN RFA) in patients with clinically-suspected vertebral endplate pain (VEP). STUDY DESIGN/SETTING Aggregated cohort study of 296 patients treated with BVN RFA at 33 global centers in three prospective clinical trials. OUTCOME MEASURES Treatment success definitions were: (1) =50% LBP visual analog scale (VAS), (2) =15-point Oswestry Disability Index (ODI), and (3) =50% VASor=15-point ODI improvements from baseline. METHODS Participant demographics, pain diagrams and LBP-exacerbating activities were analyzed using stepwise logistic regression for predictors of treatment success. RESULTS Midline LBP correlated with BVN RFA treatment success in individuals with clinically suspected VEP, though pain in the paraspinal and mid-upper gluteal regions was also present. Duration of pain=5 years (OR 2.366), lack of epidural steroid injection within 6 months (OR 1.799), and LBP exacerbation with physical activity (OR 2.099) and side-bending (OR 2.184) increased odds of treatment success, whereas exacerbation with spinal extension (OR 0.542) and baseline opioid use (OR 0.509) decreased odds of treatment success. Regressions areas under the curve (AUCs) were under 70%, indicative of low predictive value. CONCLUSIONS This study demonstrates that midline LBP correlates with BVN RFA treatment success in individuals with clinically-suspected VEP. None of the models demonstrated strong predictive value, indicating that use of objective imaging biomarkers (Type 1 and/or 2 Modic changes) and a correlating presentation of anterior spinal element pain remain the most useful patient selection factors for BVN RFA. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs. Traditionally, researchers and clinicians have assumed that the vast majority of nociceptive signals intrinsic to the spine have been discogenic. Despite this assumption, ample research demonstrates nociceptive innervation of the vertebral endplate by the basivertebral nerve (BVN). Little is known about the clinically relevant pain loci or specific presenting situations that may predispose individuals to treatment success by BVN radiofrequency ablation. This study presents pain location “maps” and investigates the relationship between low back pain (LBP) exacerbating activities and treatment response to basivertebral nerve radiofrequency ablation (BVN RFA) in patients with clinically-suspected vertebral endplate pain (VEP). Aggregated cohort study of 296 patients treated with BVN RFA at 33 global centers in three prospective clinical trials. Treatment success definitions were: (1) =50% LBP visual analog scale (VAS), (2) =15-point Oswestry Disability Index (ODI), and (3) =50% VASor=15-point ODI improvements from baseline. Participant demographics, pain diagrams and LBP-exacerbating activities were analyzed using stepwise logistic regression for predictors of treatment success. Midline LBP correlated with BVN RFA treatment success in individuals with clinically suspected VEP, though pain in the paraspinal and mid-upper gluteal regions was also present. Duration of pain=5 years (OR 2.366), lack of epidural steroid injection within 6 months (OR 1.799), and LBP exacerbation with physical activity (OR 2.099) and side-bending (OR 2.184) increased odds of treatment success, whereas exacerbation with spinal extension (OR 0.542) and baseline opioid use (OR 0.509) decreased odds of treatment success. Regressions areas under the curve (AUCs) were under 70%, indicative of low predictive value. This study demonstrates that midline LBP correlates with BVN RFA treatment success in individuals with clinically-suspected VEP. None of the models demonstrated strong predictive value, indicating that use of objective imaging biomarkers (Type 1 and/or 2 Modic changes) and a correlating presentation of anterior spinal element pain remain the most useful patient selection factors for BVN RFA.