Early Clinical Evaluation of Percutaneous Full-endoscopic Transforaminal Lumbar Interbody Fusion with Pedicle Screw Insertion for Treating Degenerative Lumbar Spinal Stenosis

Abstract

Objective: To compare the clinical efficacy of percutaneous full-endoscopic transforaminal lumbar interbody fusion (Endo-TLIF) with percutaneous pedicle screws (PPSs) performed by using a visualization system with that of minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) for the treatment of degenerative lumbar spinal stenosis (LSS).

Methods: From June 2017 to May 2018, the data of a total of 78 patients who met the selection criteria were retrospectively reviewed and were divided into the Endo-TLIF group (40 cases) and the MIS-TLIF group (38 cases) according to the surgical method used. The visual analog scale (VAS) and the Japanese Orthopaedic Association (JOA) scale were administered preoperatively and at the 1-week, 3-month, and 1-2-year follow-ups. The fusion rate and major complications, including revision, were also recorded.

Results: All the patients were followed up for 24 to 34 months, with an average follow-up of 30.7 months. The intraoperative blood loss and length of hospital stay for the Endo-TLIF group (60.56 ± 0.36 mL, 8.12 ± 0.92 days, respectively) were statistically significantly lower than those for the MIS-TLIF group (65.47 ± 0.91 mL, 9.66 ± 1.34 days, respectively) (P < 0.05). The VAS and JOA scores of the patients in the two groups at postoperative 1 week, 3 months, 1 year, 2 years (Endo-TLIF VAS: 4.16 ± 0.92, 3.72 ± 1.54, 1.32 ± 0.45, 1.29 ± 0.34; JOA:16.71 ± 0.99, 19.86 ± 0.24, 24.91 ± 0.97, 25.88 ± 0.52; MIS-TLIF VAS: 4.17 ± 1.41, 2.98 ± 0.91, 1.54 ± 0.32, 1.33 ± 0.18; JOA: 16.67 ± 0.67, 19.58 ± 0.65, 25.33 ± 0.73, 25.69 ± 0.33) were statistically significantly improved from the preoperative scores (Endo-TLIF: 8.45 ± 1.44, 14.36 ± 0.56; MIS-TLIF: 8.11 ± 0.93, 14.45 ± 0.34, respectively) (P < 0.01). The VAS and JOA scores of the Endo-TLIF group were statistically significantly better than those of the MIS-TLIF group at 3 months and 1 year after surgery (P < 0.05). There were no statistically significant differences in the scores between the two groups at any of the other time points (P > 0.05). There was no significant difference in the intervertebral altitude between the two groups at the 3-month (11.36 ± 0.23, 11.21 ± 0.42, respectively) or final follow-up (10.88 ± 0.64, 10.81 ± 0.39, respectively) (P > 0.05). Dural tears, cerebrospinal fluid leakage, infection, and neurologic injury did not occur. Both groups showed good intervertebral fusion at the last follow-up. The intervertebral fusion rate was 97.5% (39/40) in the Endo-TLIF group and 94.7% (36/38) in the MIS-TLIF group, with no statistically significant difference between the two groups (χ² = 0.118, P = 0.731). At the final follow-up, the modified MacNab's criteria were 92.5% and 89.5% between the two groups.

Conclusion: Endo-TLIF with percutaneous pedicle screws (PPS) performed by using a visualization system for lumbar degenerative disease may be regarded as an efficient alternative surgery for degenerative lumbar spinal stenosis. It is a safe and minimally invasive way to perform this surgery and has shown satisfactory clinical outcomes.

Keywords: Endoscopic transforaminal lumbar interbody fusion; Lumbar spinal stenosis; Minimally invasive transforaminal lumbar interbody fusion; Percutaneous pedicle screw (PPS).

Fig. 1

The CT scans (A, E) of the L_4‐5 segment revealed a mass disc protruding into the spinal canal and with spinal stenosis. Axial (B) and sagittal MRI (F) revealed L_4‐5 disc degeneration, intervertebral space stenosis, spinal stenosis, and compression of the dural sac. The preoperative anteroposterior (C) and rightlateral (D) X‐ray images of the patient revealed a narrow intervertebral space and hyperosteogenesis.

Fig. 2

Percutaneous endoscopic transforaminal lumbar interbody fusion with pedicle screw insertion. (A). The puncture angle marked on the skin. (B). Radio frequency ablation was used for soft tissue removal, prehemostasis, partial facetectomy and foraminoplasty under the endoscopic visualization system. (C). Ipsilateral facetectomy and unilateral hemilaminectomy were performed under endoscopic visualization of the nerve roots, and the dural sac was decompressed. (D). Complete discectomy was performed, and the endplate was prepared under the fluoroscopic and endoscopic visualization system. (E). The endoscopic visualization system was used for transforaminal approaches to the lumbar spine. (F). Bone fragments from decompression and the allograft. (G). A lumbar interbody fusion cage was then placed under fluoroscopic and endoscopic visualization.

Fig. 3

(A). The target site, called the facet joint, was located by inserting an 18‐gauge needle under the guidance of the C‐arm to identify the L_4‐5 segment. (B and C). The working channel was rotated slowly along the direction of the guide bar in lateral (B) and anteroposterior (C) X‐ray images. (D and E). An image showing a fusion prosthetic device in the disc space. (F and G). An interbody fusion cage was used for fluoroscopic and endoscopic visualization. (H and I). Percutaneous pedicle screw fixation was conducted under fluoroscopic guidance. [Correction added on 15 January 2021, after first online publication: Figure 3 has been amended.]

Fig. 4

Schematic diagram of the key procedures of Endo‐TLIF surgery. (A). Insertion of the working channel. (B). Partial facetectomy and foraminoplasty under the endoscopic visualization system. (C, D). Discectomy and endplate preparation were performed under the fluoroscopic and endoscopic visualization system. (E). A fusion prosthetic device was implanted for measuring the height of the intervertebral space. (F). Insertion of lumbar interbody fusion cage and autologous bone fragments. (G, H). Fixation of percutaneous pedicle screws and rods.

Fig. 5

The postoperative right lateral (A) and anteroposterior (B) X‐ray images showed the final construct with the cage and percutaneous pedicle screws. No signs of spinal cord compression were found in the sagittal (C) or axial MRI scans (D) taken at 3 days postoperatively. The CT axial scans of the lumbar spine (E and F) taken on postoperative day 3 indicated that full decompression was performed. The pedicle screws and fusion device were well positioned.