Background and objectives: Epidural block in the midthoracic region is difficult, even with fluoroscopically guided methods, because of the inability to view the interlaminar space on radiographs. We have, therefore, proposed fluoroscopically guided epidural block for the midthoracic region, as well as other thoracic and lumbar regions, by use of the pedicle as a landmark to show the height of the interlaminar space.
Methods: Twenty patients scheduled to receive an indwelling epidural catheter at Th6-7, Th9-10, Th12-L1, or L3-4 were studied. The skin insertion site was at the junction of a line parallel to the vertebral column that passed through the middle of the pedicle and the lower border of vertebral body, immediately inferior to the target interlaminar space on an anteroposterior radiograph. The needle was walked up the lamina, and the interlaminar space was sought near the midline of the vertebra at the height of the pedicle.
Results: Epidural block was easily performed in all cases. No difference was observed in the angulation of the epidural needle among the groups; the mean inward and upward angulation were 38 degrees and 63 degrees , respectively, although the skin insertion site relative to the spinous process was different among the groups.
Conclusions: This study showed the usefulness of our fluoroscopically guided method for the midthoracic region, and other thoracic and lumbar regions. We propose an alternative method for a blind epidural approach at Th6-7, Th9-10, Th12-L1, or L3-4.