A Minimally Invasive, Fast Spinal Cord Lateral Hemisection Technique for Modeling Open Spinal Cord Injuries in Rats

This protocol is significant because spinal cord injuries are still prevalent today, and research is needed to further the understanding of these injuries and develop possible therapies. This technique is more accurate and reproducible than compression and contusion injuries and less invasive than injuries with complete laminectomy. So it might be a better option for a simulation of spinal cord injury than previously described procedures.

To begin, use a scalpel blade 20 to open the surgical area by placing a two to 2.5 centimeter long incision through all the layers of the skin along the spine. Position this incision parallel to the spinal column using the L1 vertebra as a midpoint, extending it approximately one centimeter in both the cranial and coddle direction along the spinal column. Mobilize the sides of the wound by cutting through the connective tissue surrounding the muscles.

Then place two parallel incisions along the spine, penetrating the periosteum. Place the incisions right next to the spinal processes on both sides, spanning the distance between the thoracic 13 and L1 vertebrae. Dissect the muscles attached to the vertebrae with the eight of a respirator until all the spinal ligaments are visible.

Place a retractor. Then remove the spinal processes of the 13th thoracic vertebra and the first lumbar vertebra Using dental bone forceps to visualize the entire surgical area. Use sterile gauze to control bleeding throughout the procedure when necessary.

Carefully lift the remainder of the L1 spinal processes, elevating the L1 vertebra arch. Remove the ligamentum flavum to access the spinal cord. Raise the coddle spinal processes further, allowing access to the severed spinal dura mater.

Tip the coddle spinal processes in the cranial direction to visualize the pia mater. Look through the pia mater for the posterior median vein, showcasing the midline of the spine. Using the vein as a directional bisector, place an incision using a microsurgical scalpel while sparing the vein.

Place the incision under the vein in the transversal plane through the anterior posterior diameter of the spinal cord. Perform the hemisection by moving the blade laterally away from the center line. Place the incision to avoid cutting the anterior spinal artery.

Ensure excess pressure is not applied on the vertebral body when cutting the spinal cord to spare the anterior spinal artery on the ventral side of the spinal cord. Do not close the dura mater directly during wound closure. Tightly suture the muscles and spinal processes, indirectly closing the small wound on the dura mater.

Close the dorsal connective tissue layer with sutures. This new minimally invasive spinal cord injury method is performed much faster than the traditional surgery approach using laminectomy and does not require additional specialized instrumentation. Hematoxylin and eosin staining were used to visualize the injury site.

Other sections can be performed along the spinal cord mimicking specific neural injuries. Regeneration can also be studied since electrodes or stem cells can be placed using this method. Most techniques utilizing open wound models of spinal cord injury implementing either hemisection or transaction can be simplified and sped up using this technique.