Percutaneous endoscopic lumbar discectomy for migrated disc herniation: classification of disc migration and surgical approaches

Abstract

Percutaneous endoscopic lumbar discectomy (PELD) for migrated disc herniations is technically demanding due to the absence of the technical guideline. The purposes of this study were to propose a radiologic classification of disc migration and surgical approaches of PELD according to the classification. A prospective study of 116 consecutive patients undergoing single-level PELD was conducted. According to preoperative MRI findings, disc migration was classified into four zones based on the direction and distance from the disc space: zone 1 (far up), zone 2 (near up), zone 3 (near down), zone 4 (far down). Two surgical approaches were used according to this classification. Near-migrated discs were treated with "half-and-half" technique, which involved positioning a beveled working sheath across the disc space to the epidural space. Far-migrated discs were treated with "epiduroscopic" technique, which involved introducing the endoscope into the epidural space completely. The mean follow-up period was 14.5 (range 9-20) months. According to the Macnab criteria, satisfactory results were as follows: 91.6% (98/107) in the down-migrated discs; 88.9% (8/9) in the up-migrated discs; 97.4% (76/78) in the near-migrated discs; and 78.9% (30/38) in the far-migrated discs. The mean VAS score decreased from 7.5 +/- 1.7 preoperatively to 2.6 +/- 1.8 at the final follow-up (P < 0.0001). There were no recurrence and no approach-related complications during the follow-up period. The proposed classification and approaches will provide appropriate surgical guideline of PELD for migrated disc herniation. Based on our results, open surgery should be considered for far-migrated disc herniations.

Strategies for Noncontained Lumbar Disc Herniation by an Endoscopic Approach : Transforaminal Suprapedicular Approach, Semi-Rigid Flexible Curved Probe, and 3-Dimensional Reconstruction CT with Discogram

“…The percutaneous endoscopic approach is limited by the difficulty in reaching the lesion due to anatomic barriers and it has been the major cause of post-operative remnant disc materials. Specifically, in cases of a compromised high grade canal or high grade migrated disc herniation, it is difficult to reach to the lesion in the epidural space initially or in the migrated disc area [14][15][16] . To overcome such limitations of endoscopic methods, we analyzed anatomic structures by three-dimensional (3D) reconstruction computed tomography (CT) images with a discogram preoperatively and applied a transforaminal suprapedicular approach for high grade inferior-migrated disc herniations, and a posterolateral approach for high grade non-contained disc hermiations using a semi-rigid flexible curved probe.…”

Percutaneous endoscopic lumbar discectomy utilizing ventral epiduroscopic observation technique and foraminoplasty for transligamentous extruded nucleus pulposus: technical note

“…In the present case, by using a simple transforaminal approach, it was not difficult to remove the transligamentous extruded HNP in the epidural space. We used 2 additional techniques to remove the migrated fragment in the epidural space: epiduroscopic observation 11 and foraminoplasty. 12 Endoscopic discectomy via a percutaneous transforaminal posterolateral approach is an alternative technique used to treat lumbar disc herniations.…”

“…11,13,14 These articles only mention that the cannula was placed at the ventral epidural space to remove the migrated fragment, and the technical details are unclear. Ruetten et al…”

“…For such HNPs, other techniques have been reported previously. 3,4,11 Among them, the epiduroscopic technique 11 can be done after administration of local anesthesia, as this technique is a modification of the transforaminal technique. During the epiduroscopic technique, the 8-mm cannula must be placed in the intervertebral foramen.…”

The Clinical Outcomes of Transforaminal Percutaneous Endoscopic Discectomy in Treating Lumbar Disc Herniation: A Review

“…For PED, the transforaminal approach can be used as the initial operation. Based on their experience of 463 cases [19], Ruetten et al commented on the usefulness of PED for recurrent HNP and consequently reported its utility [20].…”