Abstract
The aim of our study was to assess the outcome of caudal epidural injection for patients with low back pain in relation to fatty infiltration of spinal muscle. This is a prospective study. The spinal muscles were graded on sagittal section T1 MRI at the lower border of lumber 4 vertebra from 3 to 12 depending on the severity of fatty infiltration. The outcome of the intervention was assessed by improvement in pre and post intervention oswestry disability index score as well as visual analog pain score. Patients with significant fatty changes don't respond well to the caudal epidural injection.