830 SPECT-CT as a Predictor of Pain Generators in Patients Undergoing Intraarticular Injections for Chronic Neck and Back Pain

Abstract

INTRODUCTION: The ability to accurately predict pain generators for chronic neck and back pain remains elusive. The use of hybrid single-photon emission computerized tomography- computerized tomography (SPECT-CT) to guide facet injections has emerged as a potential approach to improve patient outcomes with unclear effectiveness. METHODS: A retrospective review was completed on all patients who had a SPECT-CT for evaluation of chronic back pain between January 2016 and June 2020 at a single tertiary academic center. Patients’ records were reviewed for demographic, clinical, imaging, and outcomes data. Only patients who had facet injections following SPECT-CT were included in this evaluation. Patients undergoing injections targeted at foci of abnormal radiotracer uptake were compared to patients without uptake concerning immediate positive response, visual analog score – VAS -, and need for additional injection or surgery at the target level. RESULTS: A total of 2849 patients were evaluated with a SPECT-CT for chronic neck and back pain. Of those, 340 (11.9%) patients received facet joint injections following SPECT-CT. A propensity score regression analysis adjusted for age, gender, bone mass index (BMI), hypertension, multiple targets injections and injection location showed uptake targeted injections not being associated with an improved immediate positive response (OR=0.64; 95%CI=0.34-1.21; p=0.172). In patients with a failed facet injection preceding SPECT-CT, adding SPECT-CT to guide facet injections was associated with a decrease in VAS pain scores two weeks after injection (p=0.018), particularly when changes were made to the facets being targeted (p=0.047). CONCLUSIONS: This study suggests that there is benefit with SPECT-CT especially to guide facet injections after a failed prior facet injections.