Long-term Clinical Outcomes Following Endoscopic Foraminoplasty for Patients With Single-Level Foraminal Stenosis of the Lumbar Spine

Intraoperative fluoroscopic anteroposterior view of the lower lumbar spine showing dilatation of the paraspinal muscles using cannulated dilator passed over the guide wire.

Intraoperative fluoroscopic anteroposterior view of the lower lumbar spine showing various sizes of blunt tip hand reamers used for bony decompression introduced into foramen L5 over the guidewire.

(A) Intraoperative fluoroscopic anteroposterior view of the lower lumbar spine showing bevel-ended working cannula over the muscle dilatator with the sharp end directed toward the safe working zone, snugging under the superior articular process (SAP) and medial to the nerve root. (B) Intraoperative fluoroscopic lateral view of the lower lumbar spine showing bevel-ended working cannula over the muscle dilatator with the sharp end directed toward the safe working zone, snugging under the SAP and medial to the nerve root.

Intraoperative fluoroscopic anteroposterior view of the lower lumbar spine showing the position of the electric burr with curved tip used for bone drilling of teh caudal part of L5 pedicle to adequately decompress the exiting nerve root.

Intraoperative view showing decompression of L5 nerve root in the left foramen. Blunt tip probe is used for liberation of the nerve root from the adhesions to the disc. The superior foraminal ligament (SFL) should be cut to fully accomplish and maintain adequate foraminoplasty and pulsatility of the nerve. EN, exiting nerve root; FJ, facet joint; IVD, intervertebral disc; TN, descending nerve, *, axilla.

Differences in consecutive timepoints for the visual analog scale (VAS) for pain (A) and the Oswestry Disability Index (ODI) (B). Differences were summarized with boxplots. Lower and upper box limits represent the first quartile (Q₁) and third quartile (Q₃) while the thick line inside the box represents median. Whiskers are connecting minimum or maximum values within inner fence calculated as 1.5× interquartile range (calculated as Q₃–Q₁) below Q₁ or above Q₃, respectively. Any measurements that are not within inner fence are considered outliers and represented with points. Statistically significant differences (resulting from post hoc tests) are presented above boxplots with asterisks according to the following P value pattern: 0.05 > * > 0.01 > ** > 0.001 > ***.