Feasibility of Endoscopic Transforaminal Lumbar Interbody Fusion(eTLIF) through the Posterior Paraspinal Approach: Technical Note and Preliminary Result
Abstract Background: Implementation of endoscopic spine surgery in the management of degenerative lumbar diseases has significantly reduced the need for fusion surgeries. The performance of a MIS-TLIF using an endoscope offers some distinct advantages, such as allowing better visualization the disc space, enhanced endplate preparation and contralateral decompression. The objective of this study was to analyze the preliminary clinical and radiological outcomes of the technique of endoscopic transforaminal lumbar interbody fusion (eTLIF).Materials and Methods: eighteen consecutive patients with degenerative lumbar disease underwent eTLIF through a conventional paraspinal approach. Their clinical outcomes were evaluated with visual analog scale(VAS) leg pain score, Oswestry Disability Index(ODI) and the MacNab's criteria; radiological outcome measured with segmental lordosis, global lumbar lordosis, disc height on plain radiograph and percentage of potential fusion mass on CT scan at pre-operative, post-operative and final follow up period. Intra operative and post-operative complications were noted.Results: Mean age was 63. 71 years and Mean follow-up periods was 7.78 months. In the X-ray result, mean segmental lordosis angle(SLA) improved in pre-operative/post-operative/follow-up period 9.87±2.74 degree/ 11.79±3.74 degree/ 10.56±3.69 degree (p > 0.01); mean lumbar lordosis angle(LLA) improved 37.1±7.04 degree/ 39.2±7.13 degree/ 35.7±7.25 degree (p > 0.01). Mean preoperative disc height(DH) improved from 8.97±1.49 mm/ 12.34±1.39 mm/ 11.44±1.98 mm (p < 0.01). In the CT result, Average percentage of fusion mass was 42.61%. VAS was improved significantly, 7.67±1.13 / 3.39±1.38 / 2.5±1.34 and ODI was improved significantly, 74.9±8.03/ 34.56±8.80 / 27.76±8.64 by each preoperative / postoperative / final follow-up. In the clinical result, excellent was 5 cases and good was 13 cases. Conclusion: According to the results of this study, endoscopic TLIF was feasible procedure with an advantage of better visualization and preservation of endplate, minimal blood loss and minimal post-operative pain with early mobilization. In addition, the fusion volume as measured on post-operative CT scans, occupied 40% to 50% of disc space along with the use of 3D printed cages expected to give higher fusion rates. In conclusion, our preliminary results show that endoscopic TLIF is considered to be a viable surgical procedure with further long-term follow-up warranted.