The incidence of lumbar disc fragment migration is approximately 35%–72% of which 34% are high-grade up-migrated discs. Translaminar keyhole approach is a minimally invasive and true tissue sparing technique which has been applied to approach migrated disc herniation. The unilateral biportal endoscopic approach is an emerging technique among endoscopic spine surgery that combines the advantages of microscopic surgery with endoscopic surgery. In this technical report we demonstrate the surgical technique of performing the translaminar keyhole approach with unilateral biportal endoscopic spine surgery to treat high-grade up-migrated discs. As far as we know, this is the first technical report of unilateral biportal endoscopy with translaminar keyhole approach to treat high-grade up migrated lumbar disc herniation.
The incidence of lumbar disc fragment migration is approximately 35%–72%, of which, 34% are high-grade migrated discs [
The exact location of migrated disc fragment and the ideal keyhole trajectory are planned with preoperative images, such as anteroposterior and lateral radiographs, computed tomography (CT) and three-dimensional (3D) CT scans, magnetic resonance imaging (MRI), and MRI with myelogram (
A 77-year-old woman complained of progressive low back pain irradiating to the right leg. MRI showed a right paracentral extrusion with high-grade up-migrated disc from L2-3 (
A 55-year-old man came to emergency room complaining of acute low back pain which started at the same day of his visit trying to wear his pants. At the examination the SLRT was positive and no signs of motor weakness or sensitive alteration. The patient had history of L3-4-5 neurolysis 8 months before his visit. Preoperative MRI showed mild listhesis and high-grade up-migrated disc herniation at L3-4 (right). Translaminar Keyhole UBE was performed to remove the migrated disc (
Disc fragment migration is a common condition. In 35%–72% of cases, the fragment enters the anterior epidural spaces through the posterior longitudinal ligament and migrates. Cranially extruded disc fragments can migrate to different zones; they can be localized in central, subarticular, foraminal, extraforaminal, and preforaminal zones (
Translaminar keyhole approach was introduced recently to treat patients with high-grade up-migrated lumbar disc herniation. It is a minimally-invasive technique where small (6–8 mm) translaminar fenestration is made to directly access the foraminal space and migrated disc fragments [
UBE is an emerging minimally invasive technique that offers several advantages with minimal limitations [
Numerous microscopes assisted translaminar keyhole discectomy procedures were undertaken by the author before realizing translaminar keyhole approach by UBE technique. In our experience, translaminar discectomy using UBE is the true minimally invasive surgery that sums up the advantages of both techniques to treat up-migrated disc herniations. Minimal anatomical disruption by UBE with the benefit of translaminar approach to treat the up-migrated lumbar disc herniations allows access to the surgeon to difficult areas, without compromising segmental spinal stability. Further studies will be essential to accurately establish the efficiency and safety of UBE translaminar keyhole approach. But to our knowledge, this is the first technical report of UBE utilizing translaminar approach for high-grade up migrated lumbar disc herniation and our intention with this technical report is to share our own experience to colleagues.
The UBE translaminar keyhole approach is the combination of the minimally invasive endoscopic technique that permits the free movement of the dominant hand of the surgeon to realize precise and exact control of the instruments with the most segmental spinal stability-preserving and “straightforward” approach, to treat up-migrated lumbar disc herniations. The minimal anatomical disruption claimed by UBE, adding the benefit of translaminar approach to treat the up-migrated lumbar disc herniations allows access to the surgeon to difficult areas, without compromising segmental spinal stability.
No potential conflict of interest relevant to this article.
Different preoperative images that helps to localize the exact position of up-migrated disc and plan the exact target point of keyhole. (A) X-Ray, (B) MRI Axial, Red arrow showing migrated disc fragment. (C) MRI Saggital, Yellow circle showing migrated disc fragment (D) Myelogram, Yellow circle and red arrow showing migrated disc fragment (E) 3D CT.
Skin incision point (A) Two skin incisions (two red horizontal lines) were made above and below the target point (red star), slightly separated from the midline, yellow circle showing working zone (B) C-Arm intraoperative image of the scope and diamond burr drilling the keyhole.
Preoperative sagittal MRI showing right paracentral extrusion with high-grade up-migrated disc from L2-3. (A) Sagittal MRI, (B) axial MRI, (C) myelogram. Images during and after translaminar keyhole discectomy by UBE. (D) C-arm intraoperative image of the scope and diamond burr drilling the keyhole. (E) Postoperative sagittal MRI, (F) postoperative axial MRI, (G) postoperative 3D-CT.
Preoperative sagittal MRI showing mild listhesis and high-grade up-migrated disc herniation at L3-4 (right). (A) Sagittal MRI, (B) axial MRI, (C) myelogram. Images during and after translaminar keyhole discectomy by UBE. (D) C-arm intraoperative image of the scope and diamond burr drilling the keyhole. (E) Fragment of disc herniation. (F) Postoperative sagittal MRI, (G) postoperative axial MRI, (H) postoperative 3D-CT.
A) Different zones of cranially extruded disc fragments. (B) The gradual decrease of width of the lamina in a cranial-caudal direction as width of isthmus increases.