Comparison facet joints findings in MIR and SPECT-CT bone scan in patients with low back pain

Objectives Facet join injection is a frequent treatment for low back pain in joint disease. The clue of the success is to select the right facet join to treat., There are reports that show that the results of the facet injections are better, and with less interventions , based in the the bone scan information. In our experience MRI show morel facet disease than the observed in the bone scan in the same patient. We couldn`t find comparative studies of MRI and Bone Scan in the facet arthrosis. This is a retrospectively study for compare the findings in the facet joints of lumbar spine in patients with low back pain , with MRI aand bone scan with SPECT-CT.

Methods Patients with low back pain , who had both studies with less of two months between them. Pts with known malignancy, or lumbar surgery were excluded To make accurate comparison , only the patients with SPECT-CT were included. Pts with SPECT only where excluded.

Results 113 patients filled the above requirements. 446 lumbar facet joins were interpreted as abnormal . 311 of 446 were seen only on MRI (69%), 100 were abnormal on MRI and SPECT-CT (22%) and 35 were detected only on bone scan (7.8%). So, MRI was abnormal in: 411/446 joints and SPECT-CT was abnormal in:153/411.The abnormal facet joins were most frequent in the level L4-L5 and L5-S1 without any tendency toward left-right. MRI and bone scan agree in 22% of joins (28% at L4-L5 level and 28% at L5-S1 level). 69.7% of the facets interpreted as abnormal (with arthrosis) on MRI, don't have changes in the bone scan scintigraphy. (61% in L4-L5, 64% at L5-S1). 7,8% of the facets interpreted as abnormal in the scintigraphy , were normal in the MRI (10% in L4-L5, 6% at L5-S1).

Conclusions - The information obtained in the two studies is different in 78% of cases. - In 22% of the joints, MRI and bone scan had agreement in the presence of abnormal joint. -The vast majority of the joints classified as abnormal in MRI (69%) have no functional impact on scintigraphy