FIG 3. Anatomic axial CT scan (A) after nerve injection and corresponding gross anatomic section (B) showing the L2 posterior ramus (long arrow) located into the groove bounded by the accessory process (a) and the mamillary process (m). Note the vascular pedicle (short arrows) located at the medial aspect of the medial branch. The histologic section (C) performed at this level demonstrates the medial branch (long arrow), the vascular pedicle (short arrows), the accessory process (a), and the mamillary process (m).