Fig. 1.
Paravertebral surgical exposure for ganglionic injection, showing the operative field (top panel), reference diagram (middle panel), and cleaned vertebral bones (bottom panel). (A) Initial dissection of soft tissues at the level of the fourth lumbar (L4) and L5 spinal nerves (yellow) shows the superior articular processes (sap), spinous processes (sp) and transverse processes (tp), as well as the laminar bone (lam) and accessory process on L4 (ap). The dorsal root ganglia are covered by laminar bone. (B) Removal of laminar bone superior to the foramen and the L4 accessory process reveals the distal dorsal root ganglion, recognized by its broader diameter and brownish-orange color. (C) The motorized injection system is mounted on a magnetic stand via a manual micromanipulator. The rat vertebral column is stabilized by clamping the spinous process of L5 using a clip mounted on an articulated arm that is attached to the same magnetic stand. (This would be draped during actual surgery.) Two retractors are also shown, which maintain exposure within the wound. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of the article.)