Open Posterior Lumbar Interbody Fusion Research Articles

Effect of the administration route on the hemostatic efficacy of tranexamic acid in patients undergoing short-segment posterior lumbar interbody fusion: a systematic review and meta-analysis.

Tranexamic acid (TXA) is an FDA-approved antifibrinolytic that is seeing increased popularity in spine surgery owing to its ability to reduce intraoperative blood loss (IOBL) and allogeneic transfusion requirements. The present study aimed to summarize the current literature on these formulations in the context of short-segment instrumented lumbar fusion including ≥ 1-level posterior lumbar interbody fusion (PLIF). The PubMed, Cochrane, and Web of Science databases were queried for all full-text English studies evaluating the use of topical TXA (tTXA), systemic TXA (sTXA), or combined tTXA+sTXA in patients undergoing PLIF. The primary endpoints of interest were operative time, IOBL, and total blood loss (TBL); secondary endpoints included venous thromboembolic complication occurrence, and allogeneic and autologous transfusion requirements. Outcomes were compared using random effects. Comparisons were made between the following treatment groups: sTXA, tTXA, and sTXA+tTXA. Given that sTXA is arguably the standard of care in the literature (i.e., the most common route of administration that to this point has been studied the most), the authors compared sTXA versus tTXA and sTXA versus sTXA+tTXA. Study heterogeneity was assessed with the I2 test, and grouped analysis using the Hedge's g test was performed for measurement of effect size. Forty-five articles were identified, of which 17 met the criteria for inclusion with an aggregate of 1008 patients. TXA regimens included sTXA only, tTXA only, and various combinations of sTXA and tTXA. There were no significant differences in operative time, TBL, or postoperative drainage between the sTXA and tTXA groups or between the sTXA and sTXA+tTXA groups. The present meta-analysis suggested clinical equipoise between isolated sTXA, isolated tTXA, and combinatorial tTXA+sTXA formulations as hemostatic adjuvants/neoadjuvants in short-segment fusion including ≥ 1-level PLIF. Given the theoretically lower venous thromboembolism risk associated with tTXA, additional investigations using large cohorts comparing these two formulations within the posterior fusion population are merited. Although TXA has been shown to be effective, there are insufficient data to support topical or systemic administration as superior within the open PLIF population.

Effects of Cage Implantation Depth on Sagittal Parameters and Functional Outcomes in Posterior Lumbar Interbody Fusion for the Treatment of L4-L5 Lumbar Degenerative Spondylolisthesis.

In the treatment of lumbar degenerative spondylolisthesis (LDS) with Posterior lumbar interbody fusion (PLIF) surgery, interbody fusion implants play a key role in supporting the vertebral body and facilitating fusion. The objective of this study was to assess the impact of implantation depth on sagittal parameters and functional outcomes in patients undergoing PLIF surgery. This study reviewed 128 patients with L4-L5 LDS between January 2016 and August 2019. All patients underwent an open PLIF surgery that included intravertebral decompression, implantation of pedicle screws and cage. We grouped according to the position of the center of the cage relative to the L5 vertebral endplate. Patients with the center of the cage located at the anterior 1/2 of the upper end plate of the L5 vertebral body were divided into Anterior group, and located at the posterior 1/2 of the upper end plate of the L5 vertebral body were divided into Posterior group. The lumbar lordosis (LL), segmental lordosis (SL), sacral slope (SS), pelvic incidence (PI), pelvic tilt (PT) and slope degree (SD) was measured for radiographic outcomes. We used the visual analog scale (VAS) and the oswestry disability index (ODI) score to assess functional outcomes. Paired t-test was used to compare imaging and bedside data before and after surgery between the two groups, and independent sample t-test, χ2 test and Fisher exact test were used to compare the data between the two groups. The mean follow-up of Anterior group was 44.13 ± 9.23 months, and Posterior group was 45.62 ± 10.29 months (P > 0.05). The LL, SL, PT, SS, SD and PI-LL after operation showed great improvements, relative to the corresponding preoperative values in both groups (P < 0.05). Compared to Posterior group, Anterior group exhibited far enhanced SL (15.49 ± 3.28 vs. 13.67 ± 2.53, P < 0.05), LL (53.47 ± 3.21 vs. 52.08 ± 3.15, P < 0.05) outcomes and showed depressed PI-LL (8.87 ± 5.05 vs. 10.73 ± 5.39, P < 0.05) outcomes at the final follow-up. Meanwhile, the SL in Anterior group (16.18 ± 3.99) 1 months after operation were also higher than in Posterior group (14.12 ± 3.57) (P < 0.05). We found that VAS and ODI at the final follow-up in Anterior group (3.62 ± 0.96, 25.19 ± 5.25) were significantly lower than those in Posterior group (4.12 ± 0.98, 27.68 ± 5.13) (P < 0.05). For patients with LDS, the anteriorly placed cage may provide better improvement of SL after PLIF surgery. Meanwhile, the anteriorly placed cage may achieve better sagittal parameters of LL and PI-LL and functional outcomes at the final follow-up.

A Propensity Score-Matched Cohort Study Comparing 3 Different Spine Pedicle Screw Fixation Methods: Freehand, Fluoroscopy-Guided, and Robot-Assisted Techniques.

This study aimed to compare the accuracy of robotic spine surgery and conventional pedicle screw fixation in lumbar degenerative disease. We evaluated clinical and radiological outcomes to demonstrate the noninferiority of robotic surgery. This study employed propensity score matching and included 3 groups: robot-assisted mini-open posterior lumbar interbody fusion (PLIF) (robotic surgery, RS), c-arm guided minimally invasive surgery transforaminal lumbar interbody fusion (C-arm guidance, CG), and freehand open PLIF (free of guidance, FG) (54 patients each). The mean follow-up period was 2.2 years. The preoperative spine condition was considered. Accuracy was evaluated using the Gertzbein-Robbins scale (GRS score) and Babu classification (Babu score). Radiological outcomes included adjacent segmental disease (ASD) and mechanical failure. Clinical outcomes were assessed based on the visual analogue scale, Oswestry Disability Index, 36-item Short Form health survey, and clinical ASD rate. Accuracy was higher in the RS group (p < 0.01) than in other groups. The GRS score was lower in the CG group, whereas the Babu score was lower in the FG group compared with the RS group. No significant differences were observed in radiological and clinical outcomes among the 3 groups. Regression analysis identified preoperative facet degeneration, GRS and Babu scores as significant variables for radiological and clinical ASD. Mechanical failure was influenced by the GRS score and patients' age. This study showed the superior accuracy of robotic spine surgery compared with conventional techniques. When combined with minimally invasive surgery, robotic surgery is advantageous with reduced ligament and muscle damage associated with traditional open procedures.

Comparative Outcome Data Using Different Techniques for Posterior Lumbar Fusion: A Large Single-Center Study.

Retrospective single-center study. This study aims to evaluate perioperative and intermediate-term clinical outcomes of patients undergoing different lumbar fusion techniques. Various open and minimally invasive techniques for lumbar fusion are available, but previous studies comparing lumbar fusion techniques have heterogeneous data, making interpretation challenging. Between 2011 and 2018, data from 447 consecutive patients undergoing one/two-level lumbar fusion were analyzed. Posterior lumbar interbody fusion (PLIF) with bilateral muscle strip or Wiltse approach, open transforaminal lumbar interbody fusion (TLIF) and minimally invasive TLIF, and posterolateral fusion only were among the surgical techniques used. Core outcomes measure index (COMI) questionnaires were distributed before surgery and at 3 months, 1 year, and 2 years postoperatively to establish patient selfreported outcome measures. Demographic data (age, gender, and body mass index [BMI]) for each patient were also collected in addition to surgical indication, previous operative history, perioperative outcomes, and complications, and whether later revision surgery was required. Pearson's chi-square test, Kruskal-Wallis test, repeated measure mixed-effects models, and ordinal logistic regression were used for statistical analysis. Postoperative COMI scores improved across all procedures compared with pre-surgery (p<0.001). There was no significant difference between different postoperative COMI scores. Significant predictors of higher postoperative COMI score included higher pretreatment COMI score (p≤0.001), previous surgery (p≤0.04), younger age (p≤0.05), higher BMI (p≤0.005), and the indications of lytic spondylolisthesis (p=0.02) and degenerative disc disease (p<0.001). Patients undergoing minimally invasive TLIF had a significantly shorter post-surgery stay than patients undergoing open PLIF (Kruskal-Wallis test, p=0.03). At 2 years postoperatively, there was no significant difference in clinical outcomes between open and minimally invasive techniques. These findings suggest that the main determinant of surgical approach should be surgeon preference and training.

Lateral lumbar interbody fusion (LLIF) reduces total lifetime cost compared with posterior lumbar interbody fusion (PLIF) for single-level lumbar spinal fusion surgery: a cost-utility analysis in Thailand

BackgroundLumbar interbody fusion techniques treat degenerative lumbar diseases effectively. Minimally invasive lateral lumbar interbody fusion (LLIF) decreases soft tissue disruption and accelerates recovery better than standard open posterior lumbar interbody fusion (PLIF). However, the material cost of LLIF is high, especially in Thailand. The cost-effectiveness of LLIF and PLIF in developing countries is unclear. This study compared the cost-utility and clinical outcomes of LLIF and PLIF in Thailand.MethodsData from patients with lumbar spondylosis who underwent single-level LLIF and PLIF between 2014 and 2020 were retrospectively reviewed. Preoperative and 1-year follow-up EuroQol-5D-5L and healthcare costs were collected. A cost-utility analysis with a lifetime time horizon was performed using a societal perspective. Outcomes are reported as the incremental cost-effectiveness ratio (ICER) and quality-adjusted life-year (QALY) gained. A Thai willingness-to-pay threshold of 5003 US dollars (USD) per QALY gained was used.ResultsThe 136 enrolled patients had a mean age of 62.26 ± 11.66 years. Fifty-nine patients underwent LLIF, while 77 underwent PLIF. The PLIF group experienced greater estimated blood loss (458.96 vs 167.03 ml; P < 0.001), but the LLIF group had a longer operative time (222.80 vs 194.62 min; P = 0.007). One year postoperatively, the groups’ Oswestry Disability Index and EuroQol-Visual Analog Scale scores were improved without statistical significance. The PLIF group had a significantly better utility score than the LLIF group (0.89 vs 0.84; P = 0.023). LLIF’s total lifetime cost was less than that of PLIF (30,124 and 33,003 USD). Relative to PLIF, LLIF was not cost-effective according to the Thai willingness-to-pay threshold, with an ICER of 19,359 USD per QALY gained.ConclusionsLLIF demonstrated lower total lifetime cost from a societal perspective. Regard to our data, at the 1-year follow-up, the improvement in patient quality of life was less with LLIF than with PLIF. Additionally, economic evaluation modeling based on the context of Thailand showed that LLIF was not cost-effective compared with PLIF. A strategy that facilitates the selection of patients for LLIF is required to optimize patient benefits.

Bilateral ultrasound-guided erector spinae plane block versus wound infiltration for postoperative analgesia in lumbar spinal fusion surgery: a randomized controlled trial

PurposeBoth erector spinae plane block and wound infiltration are used to improve analgesia following spinal fusion surgery. Herein, we compared the analgesic effect of bilateral erector spinae plane block with wound infiltration in this patient population.MethodsIn this randomized trial, 60 patients scheduled for elective open posterior lumbar interbody fusion surgery were randomized to receive either ultrasound-guided bilateral erector spinae plane block before incision (n = 30) or wound infiltration at the end of surgery (n = 30). Both groups received standardized general anesthesia and postoperative analgesia, including patient-controlled analgesia with sufentanil and no background infusion. Opioid consumption and pain intensity were assessed at 2, 6, 12, 24, and 48 h after surgery. The primary outcome was cumulative opioid consumption within 24 h after surgery.ResultsAll 60 patients were included in the intention-to-treat analysis. The equivalent dose of sufentanil consumption within 24 h was significantly lower in patients given erector spinae plane block (median 11 μg, interquartile range 5–16) than in those given wound infiltration (20 μg, 10 to 43; median difference − 10 μg, 95% CI − 18 to − 3, P = 0.007). The cumulative number of demanded PCA boluses was significantly lower with erector spinae plane block at 6 h (median difference − 2, 95% CI − 3 to 0, P = 0.006), 12 h (− 3, 95% CI − 6 to − 1, P = 0.002), and 24 h (− 5, 95% CI − 8 to − 2, P = 0.005) postoperatively. The proportion given rescue analgesia was also significantly lower in patients given erector spinae plane block group within 48 h (relative risk 0.27, 95% CI 0.07 to 0.96, P = 0.037). There were no statistical differences in pain intensity at any timepoints between groups. No procedure-related adverse events occurred.ConclusionsCompared with wound infiltration, bilateral ultrasound-guided erector spinae plane block decreases short-term opioid consumption while providing similar analgesia in patients following lumbar spinal fusion surgery.Chinese Clinical Trial Registry: ChiCTR2100053008.

Clinical outcomes of unilateral biportal endoscopic lumbar interbody fusion (ULIF) compared with conventional posterior lumbar interbody fusion (PLIF)

Background ContextIn recent years, unilateral biportal endoscopic lumbar interbody fusion (ULIF) has been more and more favored by spinal surgeons because of its advantages of low trauma, rapid recovery, high fusion rate and fewer complications. PurposeTo compare the clinical effects of ULIF with those of conventional open posterior lumbar interbody fusion (PLIF). Study DesignProspective case control study. Patient SampleTwenty-seven patients treated by ULIF and thirty-three patients treated by PLIF. Outcome MeasuresThe preoperative baseline and surgical technique-related outcomes (mean operation time, blood loss during operation, postoperative drainage, and postoperative hospital stay) were compared between the two groups. The clinical status of the two groups before and after surgery were also compared: visual analogue scale (VAS) score of the legs and back, Japanese Orthopedic Association (JOA) score and Oswestry Disability Index (ODI). The clinical laboratory indexes of the two groups before and after the operation were compared: C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), creatine phosphokinase (CPK), interleukin-6 (IL-6), tumor necrosis factor–α (TNF-α), as well as the incidence of complications, such as dural tear, nerve root injury and infection. MethodsAdult patients who underwent L3–S1 single level lumbar interbody fusion were included in the study. They were divided into a PLIF group and a ULIF group according to the type of surgery. This study comprised 60 cases: 27 cases in the ULIF group and thirty-three cases in the PLIF group. ResultsThere was no significant difference in preoperative baseline between the two groups. The ULIF group experienced less blood loss, postoperative drainage and a shorter postoperative hospital stay than the PLIF group; however the ULIF group required a longer operation time than the PLIF group (p<.05). CRP, ESR, CPK, IL-6, and TNF-α levels of the PLIF group were all significantly higher than those of the ULIF group 5 days after surgery (p<.05). The improvements in the VAS scores for back pain, VAS scores for leg pain and JOA score in the ULIF group were all significantly better than those in the PLIF group at 5 days after surgery (p<.05). There was no significant difference in fusion rate at 6 months between the 2 groups (p>.05). ConclusionsThis study showed that ULIF and PLIF were both effective surgical techniques for lumbar interbody fusion. However, ULIF caused less bleeding, reduced inflammatory reaction, less tissue damage and faster postoperative recovery compared with PLIF. Both long-term follow-up and larger clinical studies are needed to validate the clinical and radiological results of this surgery.

Percutaneous Endoscopic Posterior Lumbar Interbody Fusion with Unilateral Laminotomy for Bilateral Decompression Vs. Open Posterior Lumbar Interbody Fusion for the Treatment of Lumbar Spondylolisthesis.

BackgroundEndoscopic lumbar interbody fusion is a new technology that is mostly used for single-segment and unilateral lumbar spine surgery. The purpose of this study is to introduce percutaneous endoscopic posterior lumbar interbody fusion (PE-PLIF) with unilateral laminotomy for bilateral decompression (ULBD) for lumbar spondylolisthesis and evaluate the efficacy by comparing it with open posterior lumbar interbody fusion (PLIF).MethodsTwenty-eight patients were enrolled in PE-PLIF with the ULBD group and the open PLIF group. The perioperative data of the two groups were compared to evaluate the safety of PE-PLIF with ULBD. The visual analog scale (VAS) back pain, VAS leg pain, and Oswestry Disability Index (ODI) scores of the two groups preoperatively and postoperatively were compared to evaluate clinical efficacy. Preoperative and postoperative imaging data were collected to evaluate the effectiveness of the operation.ResultsNo differences in baseline data were found between the two groups (p > 0.05). The operation time in PE-PLIF with the ULBD group (221.2 ± 32.9 min) was significantly longer than that in the PLIF group (138.4 ± 25.7 min) (p < 0.05), and the estimated blood loss and postoperative hospitalization were lower than those of the PLIF group (p < 0.05). The postoperative VAS and ODI scores were significantly improved in both groups (p < 0.05), but the postoperative VAS back pain score in the PE-PLIF group was significantly lower than that in the PLIF group (p < 0.05). The excellent and good rates in both groups were 96.4% according to MacNab’s criteria. The disc height and cross-sectional area of the spinal canal were significantly improved in the two groups after surgery (p < 0.05), with no difference between the groups (p > 0.05). The fusion rates in PE-PLIF with the ULBD group and the PLIF group were 89.3% and 92.9% (p > 0.05), respectively, the cage subsidence rates were 14.3% and 17.9% (p > 0.05), respectively, and the lumbar spondylolisthesis reduction rates were 92.72 ± 6.39% and 93.54 ± 5.21%, respectively (p > 0.05).ConclusionThe results from this study indicate that ULBD can be successfully performed during PE-PLIF, and the combined procedure is a safe and reliable treatment method for lumbar spondylolisthesis.

Comparison of percutaneous endoscopic and open posterior lumbar interbody fusion for the treatment of single-segmental lumbar degenerative diseases

BackgroundEndoscopic lumbar interbody fusion has become an emerging technique. Some researchers have reported the technique of percutaneous endoscopic transforaminal lumbar interbody fusion. We propose percutaneous endoscopic posterior lumbar interbody fusion (PE-PLIF) as an alternative approach. The purpose of this study was to assess the clinical efficacy of PE-PLIF by comparing percutaneous endoscopic and open posterior lumbar interbody fusion (PLIF).MethodsThirty patients were enrolled in each group. Demographic data, perioperative data, and radiological parameters were collected prospectively. The clinical outcomes were evaluated by visual analog scale (VAS) and Oswestry Disability Index (ODI) scores.ResultsThe background data were comparable between the two groups. The mean operation time was longer in the PE-PLIF group. The PE-PLIF group showed benefits in less blood loss and shorter hospital stay. VAS and ODI scores significantly improved in both groups. However, the VAS score of low-back pain was lower in the PE-PLIF group. The satisfaction rate was 96.7% in both groups. The radiological outcomes were similar in both groups. In the PE-PLIF group, the fusion rate was 93.3%, and the cage subsidence rate was 6.7%; in the open PLIF group, the fusion and cage subsidence rates were 96.7% and 16.7%. There were minor complications in one patient in the PE-PLIF group and two in the open PLIF group.ConclusionsThe current study revealed that PE-PLIF is safe and effective compared with open PLIF. In addition, this minimally invasive technique may enhance postoperative recovery by reducing tissue damage and blood loss.

Comparison of Minimally Invasive Lateral Lumbar Interbody Fusion, Minimally Invasive Lateral Lumbar Interbody Fusion, and Open Posterior Lumbar Interbody Fusion in the Treatment of Single-Level Spondylolisthesis of L4-L5

To compare the outcomes of minimally invasive lateral lumbar interbody fusion (LLIF) with minimally invasive transforaminal lumbar interbody fusion (TLIF) and conventional open posterior lumbar interbody fusion (PLIF) for treating single-level spondylolisthesis at L4-L5. The patients underwent minimally invasive LLIF (n= 18), minimally invasive TLIF (n= 17), and conventional open PLIF (n= 20) for spondylolisthesis at L4-L5. Reduction of slippage, improvement in segmental lordosis, and restoration of foraminal height were measured. Perioperative parameters such as blood loss and operation time and clinical outcomes such as visual analog scale score and Oswestry Disability Index were compared. Compared with the open PLIF group, the minimally invasive LLIF group showed greater restoration of mean foraminal height, significantly smaller mean intraoperative estimated blood loss, and less mean hemoglobin reduction on the third day postoperatively. Compared with the minimally invasive TLIF group, the minimally invasive LLIF group showed greater restoration of mean segmental lordosis. The minimally invasive LLIF group showed a significantly shorter mean time to start walking after surgery compared with the conventional open PLIF and minimally invasive TLIF groups. However, compared with the minimally invasive TLIF group, the minimally invasive LLIF group showed a significantly longer mean operating time. Clinical outcomes were not statistically different among the 3 groups. In the treatment of spondylolisthesis of L4-L5, minimally invasive LLIF provided an effective surgical alternative to minimally invasive TLIF or conventional open PLIF, with the advantages of less blood loss, the faster start of postoperative walking, and comparable improvement in radiologic parameters.

Surgical Outcomes and adverse effects for Minimally Invasive versus Open Posterior Lumbar Interbody Fusion

Abstract Background Minimal invasive techniques for lumbar interbody fusion is a novel surgical procedure developed to reduce approach-related morbidity associated with traditional open techniques. Objective To determine the clinical comparative effectiveness and adverse event rates of posterior minimally invasive surgery (MIS) compared to open transforaminal or posterior lumbar interbody fusion (TLIF/PLIF) for early and late outcomes by using the visual analogue scale for back pain (VAS–back) and the Oswestry Disability Index (ODI). Data Sources Medline databases (PubMed, Medscape, ScienceDirect. EMF-Portal) and all materials available in the Internet till 2018. Data Extraction If the studies did not fulfill the inclusion criteria, they were excluded. Study quality assessment included whether ethical approval was gained, eligibility criteria specified, appropriate controls, and adequate information and defined assessment measures. Conclusion MIS techniques for lumbar interbody fusion is a safe alternative for classic open procedures but due to the limited number of the included RCTs, more well-designed multicenter RCTs with larger sample sizes and long-term follow-up are still needed to compare the clinical efficacy and safety of both techniques.

Adjacent segment pathology following posterior lumbar interbody fusion for lumbar degenerative spondylolisthesis: a comparison between minimally invasive and conventional open approach

The minimally invasive (MI) approach in posterior lumbar interbody fusion (PLIF) minimizes the muscle-stripping posterior exposure of the lumbar spine; therefore, it is hypothesized that such benefits would reduce adjacent segment pathology (ASP) development. This study aimed to estimate the incidence of ASP following MI-PLIF. Retrospective study. A total of 100 patients who had undergone single-level PLIF at the L4/5 level for lumbar degenerative spondylolisthesis were retrospectively studied (MI-PLIF group: 68 patients; conventional open PLIF [O-PLIF] group; 32 patients; average follow-up period: 100.5 months). Incidence of ASP. Patients were considered to have operative ASP (OASP) if adjacent segments manifested degenerative lesions that caused clinically significant symptoms requiring surgery. Survival curves were estimated for each group using the Kaplan-Meier method. The study was not externally funded. The authors have no conflicts of interest to declare. Four (5.9%) of the 68 patients in the MI-PLIF group and 6 (18.8%) of the 32 patients in the O-PLIF group experienced OASP during the follow-up period. Kaplan-Meier analysis predicted a disease-free OASP survival rate of 98.5% (95% confidence interval [CI], 95.5%-100%) in the MI-PLIF group and 90.6% (95% CI, 81.1%-100%) in the O-PLIF group at 5 years, and 93.7% (95% CI, 86.8%-100%) in the MI-PLIF group and 71.8% (95% CI, 52.9%-97.5%) in the O-PLIF group at 10 years. MI-PLIF achieved a significantly higher survival rate in OASP than did O-PLIF (p=.04). O-PLIF was associated with a 3.97 times higher risk (odds ratio 3.97, 95% CI, 1.02-15.48; p=.04) of developing OASP in our cohort. Following MI-PLIF, the rate of OASP was predicted to be 1.5% at 5 years and 6.3% at 10 years. MI-PLIF had a lower incidence of OASP and more favorable clinical outcomes than did O-PLIF.

Radiological Assessment of Postoperative Paraspinal Muscle Changes After Lumbar Interbody Fusion With or Without Minimally Invasive Techniques.

Retrospective cohort study. Percutaneous pedicle screws (PPS) have the advantage of being able to better preserve the paraspinal muscles when compared with a traditional open approach. However, the nature of changes in postoperative paraspinal muscle after damage by lumbar fusion surgery has remained largely unknown. It is clinically important to clarify and compare changes in paraspinal muscles after the various surgeries. (1) To determine postoperative changes of muscle density and cross-sectional area using computed tomography (CT), and (2) to compare paraspinal muscle changes after posterior lumbar interbody fusion (PLIF) with traditional open approaches and minimally invasive lateral lumbar interbody fusions (LLIF) with PPS. We included data from 39 consecutive female patients who underwent open PLIF and 23 consecutive patients who underwent single-staged treatment with LLIF followed by posterior PPS fixation at a single level (L4-5). All patients underwent preoperative, 6 months postoperative, and 1-year postoperative CT imaging. Measurements of the cross-sectional area (CSA) and muscle densities of paraspinal muscles were obtained using regions of interest defined by manual tracing. We did not find any decrease of CSA in any paraspinal muscles. We did find a decrease of muscle density in the multifidus at 1 year after surgery in patients in the PILF group, but not in those in LLIF/PPS group. One year after surgery, a significant postoperative decrease of muscle density of the multifidi was observed only in patients who underwent open PLIF, but not in those who underwent LLIF/PPS.

Microendoscope-Assisted Versus Open Posterior Lumbar Interbody Fusion for Lumbar Degenerative Disease: A Multicenter Retrospective Cohort Study.

Background and objectives: Minimally invasive surgery has become popular for posterior lumbar interbody fusion (PLIF). Microendoscope-assisted PLIF (ME-PLIF) utilizes a microendoscope within a tubular retractor for PLIF procedures; however, there are no published reports that compare Microendoscope-assisted to open PLIF. Here we compare the surgical and clinical outcomes of ME-PLIF with those of open PLIF. Materials and Methods: A total of 155 consecutive patients who underwent single-level PLIF were registered prospectively. Of the 149 patients with a complete set of preoperative data, 72 patients underwent ME-PLIF (ME-group), and 77 underwent open PLIF (open-group). Clinical and radiographic findings collected one year after surgery were compared. Results: Of the 149 patients, 57 patients in ME-group and 58 patients in the open-group were available. The ME-PLIF procedure required a significantly shorter operating time and involved less intraoperative blood loss. Three patients in both groups reported dural tears as intraoperative complications. Three patients in ME-group experienced postoperative complications, compared to two patients in the open-group. The fusion rate in ME-group at one year was lower than that in the open group (p = 0.06). The proportion of patients who were satisfied was significantly higher in the ME-group (p = 0.02). Conclusions: ME-PLIF was associated with equivalent post-surgical outcomes and significantly higher rates of patient satisfaction than the traditional open PLIF procedure. However, the fusion rate after ME-PLIF tended to be lower than that after the traditional open method.

Lumbar Fusion for Spondylolisthesis: A Bayesian Network Meta-analysis of Randomized Controlled Trials.

This was a Bayesian network meta-analysis. We aimed to assess the comparative efficacies of the 5 most commonly used procedures for spondylolisthesis in a Bayesian network meta-analysis. Lumbar fusion procedures are the backbone for the surgical treatment of spondylolisthesis. However, the current evidence has only considered head-to-head comparisons of different fusion procedures and failed to definitively favor one fusion procedure over another. A Bayesian random-effects model was used, and radiographic fusion and complications were assessed by risk ratio with a corresponding 95% credible interval; Oswestry Disability Index (ODI) scores were assessed by mean difference and 95% credible interval. Furthermore, with respect to each endpoint, ranking probabilities for each fusion procedure were evaluated using the value of the surface under the cumulative ranking curve. In all, 12 studies were identified. Significant differences in associated complications were found between minimally invasive transforaminal lumbar interbody fusion (MTLIF) and each of the other 4 fusion procedures. Surface under the cumulative ranking curve results suggested that for the most effective radiographic fusion, open transforaminal lumbar interbody fusion (OTLIF) had the maximum probability of being successful (76.6%), followed by MTLIF (70.4%) and open posterior lumbar interbody fusion (OPLIF, 48.7%). In terms of ODI scores, OTLIF might be the best intervention (70.5%), followed by MTLIF (68.8%) and then OPLIF (44.0%). However, MTLIF is ranked the safest (99.8%) regarding associated complications, followed sequentially by OTLIF (57.1%) and posterolateral fusion (30.1%). OTLIF for spondylolisthesis was found to be the more efficient procedure in terms of radiographic fusion and ODI scores. Importantly, MTLIF is most likely to have a lower associated complication rate compared with other fusion procedures.

Randomized Controlled Trial of Posterior Lumbar Interbody Fusion With Ti- and CaP-Nanocoated Polyetheretherketone Cages: Comparative Study of the 1-Year Radiological and Clinical Outcome.

Polyetheretherketone (PEEK) is a popular material for posterior lumbar interbody fusion (PLIF) cages, although osseointegration remains limited. To optimize PEEK cage characteristics, titanium (Ti) and calcium phosphate (CaP) nanocoatings have been developed with proven mechanical safety. This multicenter randomized controlled trial compared the clinical and radiological outcome parameters of nanocoated and uncoated PEEK cages, up to 1 year after surgery. Standard open PLIF surgery was performed on 127 patients, randomized in 3 groups: Ti-nanocoated (n = 44), CaP-nanocoated (n = 46), and uncoated PEEK cages (n = 37). Clinical assessments up to 1 year after surgery included visual analogue scales (VASs), Oswestry Disability Index (ODI), and 36-Item Short Form Survey (SF-36). Primary radiological outcome parameters were implant stability and fusion status, assessed by x-ray and computed tomography (CT) scans. Patients, surgeons, and postsurgery analysts were blinded. PLIF surgery with all cage types resulted in significant improvements of clinical outcome parameters, exceeding the minimum clinically important differences. No significant differences in VAS, ODI, or SF-36 scores were found among the 3 groups. One year after the surgery, 65.6% of patients with uncoated PEEK cages achieved definite fusion. Significantly more patients with nanocoated PEEK cages achieved definite fusion: 93.9% for Ti nanocoating (P = .0034) and 88.0% for CaP nanocoating (P = .032). No significant differences in fusion were found between the nanocoated cage types (P = .4318). The similar clinical outcome improvements after 1 year suggest that nanocoated PEEK cages have the same safety and efficacy as the clinically accepted uncoated PEEK cages. Furthermore, nanocoated PEEK cages achieved a better fusion rate than uncoated PEEK cages at the 1-year follow-up. A 5-year follow-up study is warranted to revisit the findings. The safety, efficacy, and enhanced osseointegration of nanocoated PEEK cages were demonstrated. Osseointegration is a significant predictor of positive long-term clinical outcomes and improved implant longevity, implying a clinical added value of nanocoatings. Enhanced osseointegration becomes even more important in minimally invasive spine surgery and in patients at risk for incomplete fusion.

Laterally placed expandable interbody spacers improve radiographic and clinical outcomes: A 1-year follow-up study

IntroductionA common surgical option for the treatment of degenerative disc disease is minimally invasive lateral lumbar interbody fusion (MIS LLIF). This approach has been shown to minimize blood loss and soft tissue dissection when compared to open posterior lumbar interbody fusion. Expandable lateral interbody spacers are designed to maximize segmental lordosis, which is essential for sagittal balance correction. This study describes the clinical and radiographic outcomes of patients treated with expandable interbody spacers for MIS LLIF. MethodsA retrospective, single surgeon, clinical and radiographic study was performed on 37 consecutive patients who underwent MIS LLIF at 1–2 contiguous level(s) using expandable spacers. Radiographic and clinical functional outcomes were collected and compared at preoperative and postoperative time points up to 12 months. Parametric and nonparametric tests were used when appropriate with p value < 0.05 being significant (SPSS® v20.0.0 software for Windows (IBM Corp., Armonk, New York, USA) software was used to analyze data statistically). ResultsThirty-seven consecutive patients were evaluated with an average age of 60 ± 12.0 years, and 37.8% were female. Mean Visual Analog Scale (VAS) for leg and back pain decreased significantly by a mean of 6.7 ± 1.3 points from preoperative to 12 months (p < 0.001). Oswestry Disability Index (ODI) scores significantly decreased by a mean of 63.2 ± 13.2 points (p < 0.001). Lumbar lordosis improved by a mean of 2.3 ± 8.8° at 12 months postoperative (P = 0.112). There were 46 spinal levels, with 39.1% (18/46) at L4–L5 and 37.0% (17/46) at L3–L4. Anterior, middle, and posterior disc height significantly increased from preoperative to 12 months with a mean of 4.9 ± 3.5 mm, 4.2 ± 3.8 mm, and 2.2 ± 2.4 mm, respectively (p < 0.001). Mean neuroforaminal height increased by 3.4 ± 3.7 mm at 12 months (p < 0.001). Segmental lordosis improved by 3.7 ± 2.9° from preoperative to 12 months. There was 100% fusion at all levels, with no cases of radiolucency and 1 case of subsidence at 12 months. There were no reported implant-related complications, with 0% pseudoarthrosis. Estimated blood loss at both 1-level (1L) and 2-level (2L) was <50 cc. Mean operative time was 57.6 ± 15.3 min for 1 L fusions and 93.6 ± 14.0 min for 2 L fusions. Mean fluoroscopic times were 23.0 ± 10.9 sec for 1 L fusions and 32.4 ± 23.4 sec for 2 L fusions. Length of hospital stay was 3.8 ± 1.6 days for 1 L fusions and 4.2 ± 2.2 days for 2 L fusions. ConclusionSignificant increases in disc height, neuroforaminal height, segmental lordosis, and indirect decompression were achieved and maintained up to 1-year follow-up from baseline. Functional clinical outcomes were significantly improved for patients who underwent MIS LLIF using expandable interbody spacers based on decreased VAS pain scores and ODI scores at 1-year follow-up. The use of expandable spacers was shown to be safe, durable and effective for the studied patients.

Radiographic Analysis of Minimally Invasive Transforaminal Lumbar Interbody Fusion versus Conventional Open Surgery on Sagittal Lumbar-Pelvic Alignment for Degenerative Spondylolisthesis

To compare the impact of minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) with open posterior lumbar interbody fusion (PLIF) on sagittal lumbar-pelvic radiographic parameters for degenerative spondylolisthesis (DS). Of 48 patients with L4 single segmental DS, 25 underwent MIS-TLIF with Quadrant system and 23 underwent conventional open PLIF. Comparisons of data from the preoperative and final follow-up standing lateral lumbar x-rays, with the bilateral femoral heads, of the 2 groups were conducted using the following parameters: slip percentage (SP), lumbar lordosis (LL), pelvic incidence, pelvic tilt (PT), sacral slope, lumbosacral angle, slip angle (SA), and the L1 axis and S1 distance (LASD). The slip reduction rate (ΔSP) in the OPEN group was significantly higher than in the MIS group (67 ± 34% vs. 37 ± 51%, P= 0.018). The change of SA (ΔSA) in the OPEN group was significantly higher than in the MIS group (3 ± 7° vs. -3 ± 5°, P= 0.003). The change of LASD (ΔLASD) in the OPEN group was significantly lower than in the MIS group (-4 ± 15 mm vs. 4 ± 9 mm, P= 0.033). There were positive correlations between the preoperative SP and LASD, and ΔSA and the change of LL (ΔLL), and a negative correlation between ΔLL and the change of PT (ΔPT). For low-grade DS, open PLIF has a higher rate of slip reduction compared to MIS-TLIF, and significantly reduces LASD, therefore, it is more conducive to improving lumbar sagittal balance.

Safety and efficacy of an electron beam melting technique-manufactured titanium mesh cage for lumbar interbody fusion

Electron beam melting (EBM) technique enables cage design changes such as the integration of guide rails on the cage surface or a3D matrix for osseointegration. Achange in manufacturing technique or design can lead to adecreased fusion rate or impaired applicability. The aim of the present study was to evaluate cage handling, lordosis reconstruction capability, and fusion rate 1year after surgery. In this study, 50patients who had undergone minimally invasive transforaminal lumbar interbody fusion (TLIF) or open posterior lumbar interbody fusion (PLIF) using an EBM-manufactured cage were retrospectively included. Fusion evaluation was based on routinely performed CTs and flexion-extension radiographs 12months postoperatively. Lumbar and segmental lordosis were compared between pre-, post, and 1‑year follow-up. Postoperative cage position was used for evaluation of cage handling. The radiological fusion rate was 97% at the 1‑year follow-up. Two cages were placed into the endplates during surgery without an effect on fusion. In 31% of the cages, placement at the anterior third of the disk space was possible. Lumbar lordosis was improved by a mean of 5° and segmental lordosis by a mean of 4°. At final follow-up, 1° was lost in both parameters. No implant-associated complications were registered. The implant is safe and leads to avery high fusion rate. Alearning curve results from the fact that the cage follows adefined radius dictated by the guide rails. Addressing this, exact placement at the anterior endplate can be achieved.

Friday, September 28, 2018 9:00 AM–10:00 AM best papers Friday: 149. Comparison of minimal invasive and open transforaminal lumbar interbody fusion in the treatment of single-level lumbar spine degenerative diseases with minimum 6-year follow-up

BACKGROUND CONTEXT With the development of spine minimally invasive techniques, more and more surgeons make the choice of minimal invasive posterior transforminal lumbar interbody fusion (MIS-TLIF) for treating single level lumbar spine degenerative diseases. PURPOSE The aim of this study was to compare the fusion rate between MIS-TLIF and open posterior transforminal lumbar interbody fusion (OPEN-TLIF), and to evaluate the safety and reliability of MIS-TLIF for treating single level lumbar spine degenerative diseases. STUDY DESIGN/SETTING A retrospective cohort study. PATIENT SAMPLE A total of 148 patients. OUTCOME MEASURES The operation time, intraoperative blood loss and postoperative drainage were compared between MIS-TLIF group and OPEN-TLIF group, and the fusion status of two groups were evaluated by X-ray and CT scanning. In addition, clinical outcomes in terms of back pain VAS score, leg pain VAS score, and ODI score. METHODS A retrospective cohort study was performed on consecutive 148 patients who underwent MIS-TLIFor OPEN-TLIFsurgical treatment with single level lumbar spine degenerative diseases from January 2009 to January 2011. Among them, 65 cases received MIS-TLIF and 83 cases received OPEN-TLIF. The operation time, intraoperative blood loss and postoperative drainage were compared between MIS-TLIF group and OPEN-TLIF group, and the fusion status of two groups were evaluated by x-ray and CT scanning. In addition, clinical outcomes in terms of back pain VAS score, leg pain VAS score, and ODI score. RESULTS The operation time, intraoperative blood loss and postoperative drainage in MIS-TLIF group were 218.4±38.2minutes, 156.4±58.6ml and 132.8±64.5ml respectively, and in OPEN-TLIF group the outcomes were 123.6±45.4minutes, 326.6±85.4ml and 358.2±94.4ml respectively. Although the operation time of MIS-TLIF group was longer than OPEN-TLIF group (p .05) was noted between the two groups. Lumbar interbody fusion rate assessed by CT scanning showed 89.2% (58/65) in MIS-TLIF group and 95.2% (79/83) in OPEN-TLIF group, and the mean fusion time was 6.7±2.3 and 4.4±1.8 month, respectively. Although lumbar interbody fusion ratewas no significant (p>.05), the fusion time of MIS-TLIF group was significant longer than OPEN-TLIF group (p CONCLUSIONS For single level lumbar spine degenerative diseases, MIS-TLIF can achieve similar clinical results and lumbar interbody fusion rate compared to OPEN-TLIF. However, the fusion time of MIS-TLIF was significant longer than OPEN-TLIF due to less bone graft.