Learning Curve and Clinical Outcome of Biportal Endoscopic-Assisted Lumbar Interbody Fusion

Abstract

Interbody fusion is a common surgical technique for diseases of the lumbar spine. Biportal endoscopic-assisted lumbar interbody fusion (BE-LIF) is a novel minimally invasive technique that has a long learning curve, which can be a barrier for surgeons. Therefore, we analyzed the learning curve in terms of operative time and evaluated the outcomes of BE-LIF. A retrospective study of fifty-seven consecutive patients who underwent BE-LIF for degenerative lumbar disease by a single surgeon from January 2017 to December 2018 was performed. Fifty patients underwent a single-level procedure, and 7 underwent surgery at two levels. The mean follow-up period was 24 months (range, 14–38). Total operative time, postoperative drainage volume, time to ambulation, and complications were analyzed. Clinical outcome was measured using the Oswestry Disability Index (ODI), Visual Analog Scale (VAS) score for back and leg pain, and modified Macnab criteria. The learning curve was evaluated by a nonparametric regression locally weighted scatterplot smoothing curve. Cases before the stable point on the curve were designated as group A, and those after the stable point were designated group B. Operative time decreased as the number of cases increased. A stable point was noticed on the 400th day and the 34th case after the first BE-LIF was performed. All cases showed improved ODI and VAS scores at the final follow-up. Overall mean operative time was 171.74 ± 35.1 min . Mean operative time was significantly lower in group B ( 139.7 ± 11.6 min ) compared to group A ( 193.4 ± 28.3 min ). Time to ambulation was significantly lower in group B compared to group A. VAS and ODI scores did not differ between the two groups. BE-LIF is an effective minimally invasive technique for lumbar degenerative disease. In our case series, this technique required approximately 34 cases to reach an adequate performance level.

Learning Curve and Initial Outcomes of Full-Endoscopic Posterior Lumbar Interbody Fusion

“…An unneglected limitation of this study is the limited number of cases enrolled. Compared with the outcome reported by Kim et al, in which the technique of bi-portal endoscopy-assisted lumbar interbody fusion required approximately 34 cases to reach an adequate performance level ( 43 ), the limited number of cases may increase the statistical error and decrease the accuracy of the evaluation of the learning curve in our study. Considering the difficulty for beginners to adapt to both endoscopic lumbar operation and percutaneous pedicle screw implantation simultaneously, more cases and surgeons should be enrolled into studies for a better evaluation.…”

Learning Curve and Complications of Unilateral Biportal Endoscopy: Cumulative Sum and Risk-Adjusted Cumulative Sum Analysis

“…Study of Choi et al 20 indicated that the operation time of UBE surgery was close to the average and remained stable after the 36 th cases. Kim et al 21 considered that at least 34 cases were required to achieve sufficient mastery of lumbar interbody fusion by UBE. A surgeon with no experience with endoscopic surgery was considered to achieve adequate UBE surgical ability in the 58 th cases according to the study of Park et al 22 .Comparation of the learning curve of UBE and other endoscopic surgery has reference significance for surgeons who have engaged in other spinal endoscopic techniques in the past.…”

“…However, in the results of CUSUM analysis in this study, there was no significant difference in surgical failure rates among different phases of UBE surgery. Moreover, in previous studies using operation time as an evaluation index [20][21][22] , there was no difference in the complication rate among different learning phases.…”

Endoscopic Techniques for Lumbar Interbody Fusion: Principles and Context

“…Indeed, multiple studies have used operative time as a proxy for surgeon comfort. For example, in the context of biportal TLIF, it took 34 cases over approximately 400 days for operative times to plateau [ 43 ]. It should be noted, however, that extended learning curves are a theme across MIS spinal procedures and are almost certainly not unique to ELIFs [ 44 – 46 ].…”