Introduction: The prevalence of chronic low back pain (CLBP) can reach up to 10%. The pain phenotype however, is unknown in more than 80 %. Recently, Single Photon Emission Computed Tomography (SPECT)-CT was suggested to narrow this diagnostic imaging knowledge gap.1 This test has not been validated for the diagnosis of CLBP. We prospectively assessed the sensitivity and specificity of SPECT-CT in a patient cohort with CLBP as compared to a control group.

Methods: Patients with CLBP, with MRI inconclusive about the pain phenotype, were referred for SPECT-CT. The control group consisted of patients referred for SPECT-CT for other pathologies, if they did not experienced CLBP prior to the imaging. In total, 200 patients were included; 100 in each group.

Results: The gender and age distribution were not significantly different in both groups. The SPECT-CT showed increased bone metabolism as ‘hot spots’ in 76.6 % in the CLBP-group versus 36.9 % in the control group. Hot spots in facet joints and endplates were seen in 42.5% and 46.8% respectively in the CLBP patients and in 21.3% and 18.4% in the control group. The sensitivity of SPECT-CT in CLBP is 76.6 % and the specificity is 63 %.

Conclusions: Our findings suggest that SPECT-CT may be a valuable complementary test for identification of the pain phenotype in patients with CLBP. With a sensitivity of 76.6 %, the likelihood of a positive test in CLBP patients is high. This is the first prospective comparative study of this kind. The grade of recommendation for the use of SPECT-CT in evaluating patients with CLBP is 1C+.

Patient Care: A better understanding of the pain phenotype in patients with CLBP might help in selecting the proper treatment option and hence improve treatment outcome.

Learning Objectives: At the end of this session participants should understand the added value of SPECT-CT when looking for the exact pain phenotype in patients chronic low back pain.

References: Matar HE, Navalkissoor S, Berovic M, Shetty R, Garlick N, Casey AT, Quigley AM. Is hybrid imaging (SPECT/CT) a useful adjunct in the management of suspected facet joints arthropathy? Int Orthop. 2013;