PMC5563312_01
Sagittal T2-weighted images of an English Cocker spaniel with thoracolumbar intervertebral disk extrusion with the hips in neutral (A), extended (B), and flexed (C) positions. (A) The conus medullaris (arrow) terminates at the caudal aspect of the L7 vertebral body. (B) The conus medullaris (arrow) is displaced in a cranial direction when the hips are extended and terminates now halfway the L7 vertebral body. (C) The conus medullaris (arrow) is displaced in a caudal direction when the hips are flexed and terminates now at the level of the L7-S1 intervertebral disk space. Sagittal T2-weighted images of an English Cocker spaniel with tethered cord syndrome with a tight filum terminale with the hips in neutral (D), extended (E), and flexed (F) positions. The conus medullaris (arrow) terminates halfway the L7 vertebral body in all three positions, and only minimal displacement is seen between different positions.
fvets-04-00134-g001.jpg
PMC5563312_02_fvets-04-00134-g001.jpg
F1
With the hips in neutral position, the conus medullaris ended at the caudal aspect of the L7 vertebral body (Figure 1). The conus medullaris moved cranially until halfway the vertebral body of L7 in the extended position and moved caudally overlying the L7-S1 intervertebral disk space when an MRI was performed with the hips in a flexed position (Figure 1).
PMC5563312_02
Sagittal T2-weighted images of an English Cocker spaniel with thoracolumbar intervertebral disk extrusion with the hips in neutral (A), extended (B), and flexed (C) positions. (A) The conus medullaris (arrow) terminates at the caudal aspect of the L7 vertebral body. (B) The conus medullaris (arrow) is displaced in a cranial direction when the hips are extended and terminates now halfway the L7 vertebral body. (C) The conus medullaris (arrow) is displaced in a caudal direction when the hips are flexed and terminates now at the level of the L7-S1 intervertebral disk space. Sagittal T2-weighted images of an English Cocker spaniel with tethered cord syndrome with a tight filum terminale with the hips in neutral (D), extended (E), and flexed (F) positions. The conus medullaris (arrow) terminates halfway the L7 vertebral body in all three positions, and only minimal displacement is seen between different positions.
fvets-04-00134-g001.jpg
PMC5563312_02_fvets-04-00134-g001.jpg
F1
With the hips in neutral position, the conus medullaris ended at the caudal aspect of the L7 vertebral body (Figure 1). The conus medullaris moved cranially until halfway the vertebral body of L7 in the extended position and moved caudally overlying the L7-S1 intervertebral disk space when an MRI was performed with the hips in a flexed position (Figure 1).
Intraoperative pictures before (A) and after (B) sectioning the filum terminale. (A) Visual inspection of the vertebral canal reveals excessive caudal traction on the conus medullaris (arrow). (B) The conus medullaris regains a more cranial position after sectioning the distal aspect of the filum terminale.
fvets-04-00134-g002.jpg
PMC5563312_02_fvets-04-00134-g002.jpg
F2
After sectioning the distal aspect of the filum terminale from the cranial aspect of the lamina of S2, the conus medullaris regained a more cranial position (Figure 2).