PMC7085356_01
Preoperative lumbar MRI. (a) Midline sagittal T2-weighted MRI demonstrates the L4-5 spondylolisthesis and the prolapsed thecal sac. (b) Left of midline sagittal T2-weighted MRI with foraminal view demonstrates the left L4-5 (arrow) foraminal compression of the exiting L4 nerve. (c) Axial T2-weighted MRI demonstrates left L4-5 far lateral disc herniation compressing the exiting L4 nerve (arrow).
CRINM2020-1076847.001.jpg
PMC7085356_01_CRINM2020-1076847.001.jpg
fig1
An MRI of the lumbar spine (Figure 1) was performed and demonstrated a degenerative anterolisthesis and left lumbar 4-5 foraminal disc herniation.
Preoperative X-ray and CT scan. (a) AP X-ray demonstrates the spina bifida occulta at L4-5; note the aberrant lamina. (b) Lateral X-ray demonstrates the L4-5 spondylolisthesis and the posterior subcutaneous calcification. (c) Axial CT image demonstrates the left L4-5 abnormal facet complex and the subcutaneous calcification.
CRINM2020-1076847.002.jpg
PMC7085356_01_CRINM2020-1076847.002.jpg
fig2
Calcification in the posterior soft tissues at the level of L5 was seen on X-ray (Figures 2(a) and 2(b)) and CT (Figure 2(c)), likely related to spina bifida occulta. An enlarged and dysmorphic left L4-5 facet complex can be appreciated on the CT, as well (Figure 2(c)).
Intraoperative fluoroscopy. (a) Lateral fluoroscopic image of the beveled tubular retractor and endoscope at the L4-5 foramen. A semibendable grasper is displayed removing disc. (b) AP fluoroscopic image of the beveled tubular retractor and endoscope in the foramen and the rigid endoscopic grasper removing herniated disc.
CRINM2020-1076847.003.jpg
PMC7085356_01_CRINM2020-1076847.003.jpg
fig3
At this point, the beveled cannula tubular dilator was placed over the sequential dilators, the dilators were removed, and the 7 mm outer diameter Joimax  rigid working channel endoscope channel was inserted through the tubular retractor.  Figure 3 demonstrates the position of the tubular retractor on AP and lateral fluoroscopy. An endoscopic grasper was used to reach under the nerve under fluoroscopic (Figure 3) and endoscopic visualization (Figure 4(b)) and remove the disc herniation.  Figure 5 is an illustration of the surgical approach and instruments.
Endoscopic camera views of surgical procedure for the left lumbar 4-5 discectomy. (a) The 30-degree endoscopic camera is in Kambin's triangle upside down facing the L4 exiting root. The L4 root is demonstrated in this photo with a disc fragment seen below. (b) The endoscopic grasper is shown reaching under the L4 nerve root and removing the large disc fragment.
CRINM2020-1076847.004.jpg
PMC7085356_01_CRINM2020-1076847.004.jpg
fig4
Under endoscopic visualization, the L4 nerve root was directly visualized with the disc herniation compressing it from below (Figure 4(a)). An endoscopic grasper was used to reach under the nerve under fluoroscopic (Figure 3) and endoscopic visualization (Figure 4(b)) and remove the disc herniation.  Figure 5 is an illustration of the surgical approach and instruments.
Schematic illustration of the transforaminal endoscopic surgical approach and instruments for a foraminal disc herniation.
CRINM2020-1076847.005.jpg
PMC7085356_01_CRINM2020-1076847.005.jpg
fig5
An endoscopic grasper was used to reach under the nerve under fluoroscopic (Figure 3) and endoscopic visualization (Figure 4(b)) and remove the disc herniation.  Figure 5 is an illustration of the surgical approach and instruments.