Open Transforaminal Lumbar Interbody Fusion Research Articles

Robot-assisted minimally invasive transforaminal lumbar interbody fusion versus open transforaminal lumbar interbody fusion: a retrospective matched-control analysis for clinical and quality-of-life outcomes

Aim: To compare the screw accuracy and clinicaloutcomes between robot-assisted minimally invasive transforaminal lumbar interbody fusion (RA MIS-TLIF) and open TLIF in the treatment of one-level lumbar degenerative disease. Materials & methods: From May 2018 to December 2019, a consecutive series of patients undergoing robot-assisted minimally invasive one-level lumbar fusion procedures were retrospectively compared with matched controls who underwent one-level open TLIF procedures for clinical and quality-of-life outcomes. Results: A total of 52 patients underwent RA MIS-TLIF procedures (robot-assisted [RA] group) and 52 matched controls received freehand open TLIF procedures (open [OP] group). The RA group had more grade A screws with 96.2% one-time success rate of screw placement (p < 0.05). Besides, the RA group experienced less intraoperative blood loss and shorter length of hospital stay, while the OP group had shorter operative duration and cumulative radiation time (p < 0.001). What is more, the average VAS score for low back pain and ODI score in the RA group were lower than that in the OP group 1 month after operation (p < 0.05). Conclusion: The use of real-time, image-guided robot system may further expand the advantages of MIS-TLIF technique in terms of accuracy and safety.

Analysis of lumbosacral sagittal balance parameter variation in minimally invasive transforaminal lumbar interbody fusion with real-time 3D navigation techniques

To explore the dynamic changes of lumbosacral sagittal parameters after real-time three-dimensional navigation assisted minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) and traditional open TLIF for treatment of lumbar degenerative disease. The clinical data of 61 patients with lumbar degenerative disease underwent single-segment surgery from September 2017 to September 2019 were retrospectively analyzed. Among them, 31 cases underwent MIS-TLIF with 3D navigation techniques (MIS-TLIF group) and another 30 cases underwent conventional open TLIF (traditional open TLIF group). The basic information, operative time and intraoperative blood loss were collected. The sagittal radiologic parameters were measured before surgery and 3 months after surgery, including lumbar lordosis (LL), segmental lordosis (SL), pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), anterior disc height (ADH), posterior disc height(PDH).And the average disc height(DH) and pelvic incidence to lumbar lordosis mismatch (PI-LL) were calculated. Operative time and intraoperative blood loss in MIS-TLIF group were significantly less than in traditional open TLIF group(P<0.05). In MIS-TLIF group, LL, SL, PI-LL, and DH were significantly improved at 3 months after surgery (P<0.05), while PI, PT, and SS were not statistically different from those before surgery (P>0.05). LL, PI-LL, and DH of patients in the traditional open TLIF group were significantly improved at 3 months after surgery (P<0.05), while the PI, PT, SS, and SL were not statistically different from those before surgery (P>0.05). LL change showed a significant correlation with SL change (r= 0.433, P<0.001). Change in SL closely correlated to change in ADH (r=0.621, P<0.05) and PDH(r=0.527, P<0.05). Real-time navigation-assisted MIS-TLIF and traditional open TLIF can recover DH in a short term for lumbar degenerative diseases, improve LL and PI-LL, and make the arrangement of the sagittal plane of the lumbosacral region more coordinated after surgery. But only the navigation assisted MIS -TLIF can significantly improve SL. Compared with traditional open TLIF, real-time navigation assisted MIS-TLIF in the treatment of degenerative lumbar diseases has the advantages of short operation time and less intraoperative bleeding.

A Retrospective Analysis of Superior Facet Joint Violation Between Open and Minimally Invasive Transforaminal Lumbar Interbody Fusion and its Relation to Adjacent Segment Disease.

A retrospective study. The aim was to analyze the superior facet joint violation (SFV) between open transforaminal lumbar interbody fusion (open-TLIF) and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) and its effect on the superior and inferior adjacent segment disc height, segmental lordosis, lumbar lordosis, and facet joint degeneration. We compared SFV between open-TLIF and MIS-TLIF and its correlation with different factors as well as its effect on adjacent segment disease. We retrospectively studied data of patients undergoing single level TLIF surgery from January 2013 to February 2016 in single institutional hospital. Axial and coronal postoperative computed tomography scan images were used to analyze SFV. In secondary analysis patients were divided into nonfacet violation group (NSFVG) and facet violation group (SFVG) and compared the changes on the superior and inferior adjacent level disc height, segmental lordosis, lumbar lordosis, and facet joint degeneration. Mean SFV grade was significantly greater in MIS-TLIF compared with open-TLIF (odds ratio: 0.638, confidence interval: 0.431-0.944; P=0.025). There was more grade 2 (10.71% vs. 5.60%) and grade 3 (4.46% vs. 1.29%) SFV in MIS-TLIF. Patient with age below 60 and body mass index (BMI) >30 kg/m2 in MIS-TLIF were more prone to high-grade SFV compared with open-TLIF. Further, logistic regression showed patients with BMI ≥30 kg/m2 has 7.137 increased odds of high-grade SFV (95% confidence interval: 3.261-15.618; P=0.000) compared with patients with BMI <30 kg/m2. Compared with NSFVG, SFVG has more SFV (0.096±0.244 vs. 0.177±0.317; P=0.012) and less improvement in lumbar visual analog scale scores -0.65±0.073 versus -0.67±0.074 (P=0.006). MIS-TLIF has more high-grade SFV as well as overall mean SFV in comparison to open-TLIF with BMI >30 kg/m2 and location of pedicle screw as an independent risk factor for SFV and risk of adjacent segment disease increases with SFV. Level III.

Comparison of (Partial) economic evaluations of transforaminal lumbar interbody fusion (TLIF) versus Posterior lumbar interbody fusion (PLIF) in adults with lumbar spondylolisthesis: A systematic review

IntroductionThe demand for spinal fusion surgery has increased over the last decades. Health care providers should take costs and cost-effectiveness of these surgeries into account. Open transforaminal lumbar interbody fusion (TLIF) and posterior lumbar interbody fusion (PLIF) are two widely used techniques for spinal fusion. Earlier research revealed that TLIF is associated with less blood loss, shorter surgical time and sometimes shorter length of hospital stay, while effectiveness of both techniques on back and/or leg pain are equal. Therefore, TLIF could result in lower costs and be more cost-effective than PLIF. This is the first systematic review comparing direct and indirect (partial) economic evaluations of TLIF with PLIF in adults with lumbar spondylolisthesis. Furthermore, methodological quality of included studies was assessed.MethodsSearches were conducted in eight databases for reporting on eligibility criteria; TLIF or PLIF, lumbar spondylolisthesis or lumbar instability, and cost. Costs were converted to United States Dollars with reference year 2020. Study quality was assessed using the bias assessment tool of the Cochrane Handbook for Systematic Reviews of Interventions, the Level of Evidence guidelines of the Oxford Centre for Evidence-based Medicine and the Consensus Health Economic Criteria (CHEC) list.ResultsOf a total of 693 studies, 16 studies were included. Comparison of TLIF and PLIF could only be made indirectly, since no study compared TLIF and PLIF directly. There was a large heterogeneity in health care and societal perspective costs due to different in-, and exclusion criteria, baseline characteristics and the use of costs or charges in calculations. Health care perspective costs, calculated with hospital costs, ranged from $15,867-$43,217 in TLIF-studies and $32,662 in one PLIF-study. Calculated with hospital charges, it ranged from $8,964-$51,469 in TLIF-studies and $21,838-$93,609 in two PLIF-studies. Societal perspective costs and cost-effectiveness, only mentioned in TLIF-studies, ranged from $5,702/QALY-$48,538/QALY and $50,092/QALY-$90,977/QALY, respectively. Overall quality of studies was low.ConclusionsThis systematic review shows that TLIF and PLIF are expensive techniques. Moreover, firm conclusions about the preferable technique, based on (partial) economic evaluations, cannot be drawn due to limited studies and heterogeneity. Randomized prospective trials and full economical evaluations with direct TLIF and PLIF comparison are needed to obtain high levels of evidence. Furthermore, development of guidelines to perform adequate economic evaluations, specified for the field of interest, will be useful to minimize heterogeneity and maximize transferability of results.Trial registrationProspero-database registration number: CRD42020196869.

Clinical and Radiological Outcome of Minimally Invasive- Transforaminal Lumbar Interbody Fusion in Patients with Single or Double-Level Involvement with Minimum 2-Year Follow-up

Purpose: The objective of this study is to analyze the clinical and radiological outcome of Minimally Invasive-Transforaminal Lumbar Interbody Fusion (MIS-TLIF) in terms of estimated blood loss (EBL), operative time, length of stay (LOS) in the hospital, complication, Oswestry disability index (ODI) score, visual analog scale (VAS) score, and parameters of sagittal spinal balance before and after surgery. The parameters of sagittal spinal balance included in this study were pelvic Incidence (PI), lumbar lordosis, focal lordosis at the index level. Materials and Methods: All cases were retrospectively followed up. Single-level and double-level MIS-TLIF procedures for back pain and leg pain operated between 2015 and 2018 were included in the study. PI, Lumbar lordosis, Focal lordosis at index level was measured on preoperative, post-operative, and final follow-up lateral lumbosacral X-ray in the supine position. Demographic data, intraoperative blood loss, operative time, LOS, ODI score, and VAS score at different times were reviewed and analyzed. Results: Fifty-four patients were included among them 24 were male and 30 were female. The average age of the patients was 51.6 ± 12.1 years. Sixteen double-level surgery and 38 single-level surgeries. The average value of follow-up was found to be 39.6 ± 12.4 months. The average value of operative time, the EBL and the LOS were 170.8 ± 19.8 min, 132.1 ± 34.8 mL, and 4.8 ± 0.8 days, respectively. The average PI was 54.9 ± 11.2° preoperatively, 55.0 ± 10.7° postoperatively and 54.8 ± 10.9° at the final follow-up. Pre-operative lumbar lordosis and focal lordosis were 44.55 ± 12.9° and 7.76 ± 5.2°, respectively with postoperatively and final follow-up to 48.88 ± 13.1° and 10.62 ± 5.1°, respectively. VAS score and ODI scales were improved significantly from preoperative 8.4 ± 0.9 and 56.3 ± 4.9, respectively, to postoperatively and final follow-up 2.0 ± 0.8 and 21.6 ± 5.4, respectively. The postoperative complications and revision occurred in 8 (14.8%) and 4 (7.4%) patients, respectively. Conclusion: MIS-TLIF is a novel technique with the good radiological and clinical outcome with decreased perioperative morbidity. It is also superior to open TLIF in terms of EBL, hospital LOS, operative time, perioperative morbidity, and surgical complications. Keywords: Minimally invasive-transforaminal lumbar interbody fusion, Clinical improvement, Pelvic incidence, Lumbar lordosis, Focal lordosis

A novel lumbar total joint replacement may be an improvement over fusion for degenerative lumbar conditions: a comparative analysis of patient-reported outcomes at one year

Background contextEffective alternatives to lumbar fusion for degenerative conditions have remained elusive. Anterior total disc replacement does not address facet pathology or central/recess stenosis, resulting in limited indications. A posterior-based motion-preserving option that allows for neural decompression, facetectomy, and reconstruction of the disc and facets may have a role. PurposeThe purpose was to compare one-year patient-reported outcomes for a novel, all-posterior, lumbar total joint replacement (LTJR – replacing both the disc and facet joints) against transforaminal lumbar interbody fusion (TLIF) for degenerative lumbar conditions warranting fusion (degenerative spondylolisthesis, recurrent disc herniation, severe foraminal stenosis requiring facet removal, and adjacent segment degeneration). Study design/settingA retrospective analysis of prospectively collected data comparing outcomes for LTJR patients to TLIF patients at an academic teaching hospital. Patient sampleAnalysis was conducted on 156 adult TLIF patients who were propensity matched to the 52 LTJR patients for a total sample of 208. Outcome measuresSelf-reported Oswestry Disability Index (ODI) and Numeric Rating Scale (NRS) for back and leg pain were compared preoperatively, 3 months and 1 year after surgery. MethodsThe implant is a motion-preserving lumbar reconstruction that replaces the function of both the disc and facets and is implanted using a bilateral transforaminal approach with complete facetectomies. Adult patients with degenerative lumbar pathology undergoing either LTJR or open TLIF were analyzed. These degenerative conditions included: grade 1 degenerative spondylolisthesis, recurrent disc herniation, adjacent segment disease, disc degeneration with severe foraminal stenosis). Trauma, tumor, grade 2 or higher spondylolisthesis, spinal deformity, and infection cases were excluded. Propensity score matching was performed to ensure parity between the cohorts. Multivariable regression analyses were done to compare the 1-year results as measured by 3 different standards to assess procedure success. ResultsAt 3 months, both the LTJR and TLIF cohorts showed significant and similar improvements in ODI and NRS back and leg pain. At 1 year, the LTJR cohort showed continued improvement in ODI and NRS back pain, while the TLIF group showed a plateau for ODI, back and leg pain. In a series of three multivariable logistic regressions, LTJR was shown to provide 3.3 times greater odds of achieving the minimal clinical symptom state in disability and pain (ODI <20%, NRS back and leg pain <2) and 2.4 and 4.1 times greater odds of achieving substantial clinical benefit (18% reduction in ODI) and minimal clinically important difference (30% reduction in ODI) as compared to TLIF. ConclusionsHere we present a comparative analysis for the first 52 patients undergoing a novel, posterior-based LTJR for the lumbar spine versus TLIF for degenerative pathology. The approach for the LTJR allows for wide neural decompression, facetectomy, and complete discectomy, with the implant working to replace the function of the disc and facets to preserve motion. At 1 year, the LTJR cohort showed significant improvement in ODI and NRS back and leg pain as compared to TLIF. These results suggest that wide neural decompression combined with motion preservation using this novel LTJR may represent a viable alternative to TLIF for treating certain degenerative conditions. A prospective controlled trial is under development to further evaluate the efficacy, safety, and durability of this procedure.

Minimally invasive versus traditional open transforaminal lumbar interbody fusion for the treatment of low-grade degenerative spondylolisthesis: a retrospective study

This was a retrospective study. We aimed to compare the clinical efficacy and safety between minimally invasive and traditional open transforaminal lumbar interbody fusion in the treatment of low-grade lumbar degenerative spondylolisthesis (LDS). 81 patients with LDS grades 1 and 2 treated in our spinal department from January 2014 to July 2016 were retrospectively analyzed. The MIS-TLIF group included 23 males and 11 females, while the TO-TLIF group included 29 males and 18 females. Follow-up points were set at 7 days, 3 months, 6 months, 12 months postoperatively and the last follow-up. Various clinical and radiological indicators were used to evaluate and compare the efficacy and safety between the two procedures. 8 cases (3 in the MIS-TLIF group and 5 in the TO-TLIF group) were loss of follow-up after discharge. And the remaining 73 patients were followed up for at least 2 years. No statistically significant difference was observed in the terms of age, sex, BMI, slippage grade, and surgical segments. The MIS-TLIF group had a longer operation and fluoroscopy time compared with the TO-TLIF group. But the MIS-TLIF group was associated with less blood loss, ambulation time, hospital stay, and time of return to work. In each group, significant improvement were observed in BP-VAS, ODI and vertebral slip ratio at any time-point of follow-up when compared with the preoperative condition. When the time-point of follow-up was less than 1 year, the MIS-TLIF group had significant advantages in the BP-VAS and ODI compared with TO-TLIF group. But no significant difference was observed in the BP-VAS and ODI at either 12 month follow-up or the last follow-up. Besides, no statistical difference was detected in vertebral slip ratio at any time-point of follow-up between the two groups. Successful intervertebral bone fusion was found in all patients and no significant difference was found in the incidence of total complications. Thus, we considered that MIS-TLIF and TO-TLIF both achieve satisfactory clinical efficacy in the treatment of low-grade single-segment LDS. But MIS-TLIF appears to be a more efficacious and safe technique with reduced tissue damage, less blood loss and quicker recovery.

Risk factors for cage retropulsion after transforaminal lumbar interbody fusion in older patients

BackgroundTo investigate the incidence of cage retropulsion (CR) following transforaminal lumbar interbody fusion (TLIF) and the associated risk factors in older patients with lumbar disorders.MethodsBetween January 2015 and December 2017, 1,880 older patients (aged >60 years) who underwent open TLIF were preliminarily enrolled in this retrospective study. The patients’ medical records were reviewed, and the risk factors potentially associated with CR were analyzed.ResultsA total of 1,662 patients (692 males and 970 females, with an average age of 68.7±5.2 years) who met the eligibility criteria were finally enrolled in this study. Following TLIF, 29 older patients (1.74%) developed CR including 12 patients with spinal stenosis, 7 patients with degenerative spondylolisthesis, 5 patients had degenerative disc diseases, 3 patients had surgical history, and 2 patients suffered isthmic spondylolisthesis. Of the 29 patients, 21 patients suffered lower back pain and/or sciatica (72.4%), while 8 patients were asymptomatic (27.6%). In multivariate analysis, screw loosening [odds ratio (OR) =7.315; 95% confidence interval (CI): 3.4–15.7] and endplate injury (OR =4.947; 95% CI: 2.3–10.6) were found to be independently associated with CR in older patients after TLIF.ConclusionsThe incidence of CR following TLIF in older patients is 1.74%. Screw loosening and endplate injury are risk factors for CR in older patients with TLIF.

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.

Biologics and Minimally Invasive Approach to TLIFs: What Is the Risk of Radiculitis?

Bone morphogenetic protein (BMP) and allograft containing mesenchymal stem cells (live cell) are popular biologic substitutes for iliac crest autograft used in transforaminal lumbar interbody fusion (TLIF). Use of these agents in the pathogenesis of postoperative radiculitis remains controversial. Recent studies have independently linked minimally invasive (MIS) TLIF with increased radiculitis risk compared to open TLIF. The purpose of this study was to assess the rate of postoperative radiculitis in open and MIS TLIF patients along with its relationship to concurrent biologic adjuvant use. Patients ≥18 years undergoing single-level TLIF from June 2012 to December 2018 with minimum 1-year follow-up were included. Outcome measures were rate of radiculitis, intra- and postoperative complications, revision surgery; length of stay (LOS), and estimated blood loss (EBL). There were 397 patients: 223 with open TLIFs, 174 with MIS TLIFs. One hundred and fifty-nine surgeries used bone morphogenetic protein (BMP), 26 live cell, 212 neither. Open TLIF: higher mean EBL, LOS, and Charlson Comorbidity Index (CCI) than MIS. Postoperative radiculitis in 37 patients (9.32% overall): 16 cases MIS BMP (15.69% of their cohort), 6 MIS without BMP (8.33%), 5 open BMP (8.77%), 10 open without BMP (6.02%). MIS TLIF versus open TLIF: no differences in 1-year reoperation rates, infection/wound complication, pseudarthrosis, or postoperative complication rate. BMP versus non-BMP: no differences in reoperation rates, infection/wound complication, pseudarthrosis, or postoperative complication rate. Multivariate logistic regression found that neither BMP (P = .109) nor MIS (P = .314) was an independent predictor for postoperative radiculitis when controlled for age, gender, body mass index, and CCI. Using paired open and MIS groups (N = 168 each) with propensity score matching, these variables were still not independently associated with radiculitis (P = .174 BMP, P = .398 MIS). However, the combination of MIS with BMP was associated with increased radiculitis risk in both the entire patient cohort (odds ratio [OR]: 2.259 [1.117-4.569], P = .023, N = 397) and PSM cohorts (OR: 2.196 [1.045-4.616], P = .038, N = 336) compared to other combinations of surgical approach and biologic use. Neither the MIS approach nor BMP use is an independent risk factor for post-TLIF radiculitis. However, risk of radiculitis significantly increases when they are used in tandem. This should be considered when selecting biological adjuvants for MIS TLIF. 3.

Functional and radiological outcome of transforaminal lumbar inter body fusion in adult degenerative spondylolisthesis, a prospective cohort study

Background: Lumbar interbody fusion is an established and widely accepted procedure for degenerative spondylolisthesis. There are various fusion techniques and choosing one technique over the other remains controversial. Objective of our study was to review the long term functional and radiological outcome of traditional open transforaminal lumbar inter body fusion (TLIF) for this condition. Design: Prospective cohort study. Methods: This prospective study was conducted on 43 symptomatic adult degenerative spondylolisthesis patients, treated with traditional open TLIF and posterior instrumentation at a tertiary care centre with a mean age of 48.2years(range 26-59 year). Functional outcome and complications were assessed clinico-radiologically with a mean follow-up of 47.6 months (range18-65 months). Results: 34 patients (80%) were rated excellent, 7 patients (15%) were rated good and 2 patients (5%) were rated poor based on the pre and postoperative questionnaire scores. Visual analogue scale (VAS) pain score improved from 7.7 preoperatively to 2.5 at the latest follow-up. Preoperative Oswestry disability index (ODI) averaged 33.8 and postoperatively improved to 63.7 out of 100. Radiographic bony fusion occurred in 41 patients (95%) at final follow-up. Retropulsion of the cage into spinal canal occurred in one patient and no other major complications happened. Conclusion: Traditional open TLIF achieved excellent functional outcome and high fusion rate in our study at a long-term follow-up, which is comparable to any other fusion technique.

P108. Propensity-matched comparison of open, navigated and robotic-assisted TLIF

BACKGROUND CONTEXT Transforaminal Lumbar Interbody Fusion (TLIF) techniques have evolved from open approaches with dissection to the lateral gutters, to navigation to improve pedicle screw placement accuracy, to robotic assistance to further minimize soft tissue dissection. It is unclear if these technologies improve process measures and minimize variability in surgical technique. PURPOSE To determine if Blood Loss, Operative Time and Length of Stay will be lower with less variability with Robotic, followed by Navigated and Open TLIF. STUDY DESIGN/SETTING Propensity matched longitudinal cohort. PATIENT SAMPLE Consecutive series of patients undergoing primary single-level TLIF. OUTCOME MEASURES Blood Loss, Operative Time and Length of Stay. METHODS A consecutive series of patients undergoing primary single-level Robotic-Assisted TLIFs (RA-TLIF, N=40) were propensity matched to patients undergoing Navigated (NavTLIF, N=51) and Open TLIF (OpTLIF, N=44) using age, sex, smoking status, BMI and ASA grade. RESULTS After propensity matching, 34 cases were included in each cohort. OR Time (184±37 vs 197±48 vs 219±50, p=0.007) was lowest and had the least variability in RA-TLIFs followed by NavTLIF and OpTLIF. Length of Stay (1.5±0.9 vs 2.5±1.2 vs 4.2±1.7, p=0.000), estimated blood loss (254±259 vs 325±288 vs 489±328, p=0.004), drain output (234±257 vs 250±137 vs 653±407, p CONCLUSIONS Operative time was lowest and had the least variability in RA-TLIFs followed by NavTLIF and OpTLIF. Length of stay, blood loss, drain output, total visible blood loss, and total volume of blood products transfused was lowest in RA-TLIFs followed by NavTLIF and OpTLIF. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

P133. Does bone morphogenic protein (BMP) use reduce pseudoarthrosis rates in single-level TLIF surgeries?

BACKGROUND CONTEXT Recombinant human bone morphogenetic protein 2 (rhBMP-2) is a popular biologic product used in transforaminal lumbar interbody fusion (TLIF) surgeries to promote fusion and avoid the morbidity associated with iliac crest autograft. However, use of rhBMP-2 and its effect on pseudarthrosis rates in TLIFs remains unknown. PURPOSE To assess the rates of pseudarthrosis in open and MIS TLIF patients, with and without concurrent rhBMP-2 use. STUDY DESIGN/SETTING Retrospective cohort study at a single academic institution. PATIENT SAMPLE Included: 317 single level TLIF patients. Consisting of 157 open TLIF (OTLIF), 115 bilateral Wiltse MIS TLIF (WTLIF), and 45 hybrid midline MIS with percutaneous pedicle or cortical screws (MTLIF). OUTCOME MEASURES Clinical characteristics, perioperative and postoperative outcomes, surgical procedure, rates of pseudarthrosis diagnosis, and revision for pseudarthrosis. METHODS Patients ≥18 years old undergoing 1-level TLIF with minimum 1-year of clinical and radiographic follow up were included. Pseudarthrosis was determined using both radiographic and clinical evaluations. Differences between groups were assessed by ANOVA and chi squared analyses. Demographic and perioperative characteristics were analyzed by multivariate logistic regression. RESULTS The cohort included 317 patients (mean age 59.68±13.29, F 52.7%). There was no significant difference in gender, BMI, or smoking status among groups (all p>.05). WTLIF had the lowest EBL (ml) (192.16±177.11mL vs 302.73±246.51 vs 363.85±370.49, respectively p= CONCLUSIONS MP use did not reduce the rate of pseudarthrosis or the number of reoperations for pseudarthrosis in this cohort. No difference in pseudarthrosis rates between the three TLIF approaches was noted. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

A Comparison of Minimally Invasive and Open Transforaminal Lumbar Interbody Fusion for Grade 1 Degenerative Lumbar Spondylolisthesis: An Analysis of the Prospective Quality Outcomes Database

It remains unclear if minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) is comparable to traditional, open TLIF because of the limitations of the prior small-sample-size, single-center studies reporting comparative effectiveness. To compare MI-TLIF to traditional, open TLIF for grade 1 degenerative lumbar spondylolisthesis in the largest study to date by sample size. We utilized the prospective Quality Outcomes Database registry and queried patients with grade 1 degenerative lumbar spondylolisthesis who underwent single-segment surgery with MI- or open TLIF methods. Outcomes were compared 24 mo postoperatively. A total of 297 patients were included: 72 (24.2%) MI-TLIF and 225 (75.8%) open TLIF. MI-TLIF surgeries had lower mean body mass indexes (29.5±5.1 vs 31.3±7.0, P=.0497) and more worker's compensation cases (11.1% vs 1.3%, P<.001) but were otherwise similar. MI-TLIF had less blood loss (108.8±85.6 vs 299.6±242.2 mL, P<.001), longer operations (228.2±111.5 vs 189.6±66.5 min, P<.001), and a higher return-to-work (RTW) rate (100% vs 80%, P=.02). Both cohorts improved significantly from baseline for 24-mo Oswestry Disability Index (ODI), Numeric Rating Scale back pain (NRS-BP), NRS leg pain (NRS-LP), and Euro-Qol-5 dimension (EQ-5D) (P>.001). In multivariable adjusted analyses, MI-TLIF was associated with lower ODI (β = -4.7; 95% CI = -9.3 to -0.04; P=.048), higher EQ-5D (β = 0.06; 95% CI=0.01-0.11; P=.02), and higher satisfaction (odds ratio for North American Spine Society [NASS] 1/2=3.9; 95% CI=1.4-14.3; P=.02). Though trends favoring MI-TLIF were evident for NRS-BP (P=.06), NRS-LP (P=.07), and reoperation rate (P=.13), these results did not reach statistical significance. For single-level grade 1 degenerative lumbar spondylolisthesis, MI-TLIF was associated with less disability, higher quality of life, and higher patient satisfaction compared with traditional, open TLIF. MI-TLIF was associated with higher rates of RTW, less blood loss, but longer operative times. Though we utilized multivariable adjusted analyses, these findings may be susceptible to selection bias.

Commentary: A Comparison of Minimally Invasive and Open Transforaminal Lumbar Interbody Fusion for Grade 1 Degenerative Lumbar Spondylolisthesis: An Analysis of the Prospective Quality Outcomes Database.

Correspondence: Luis M. Tumialán, MD, c/o Neuroscience Publications, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, 350 W. Thomas Rd., Phoenix, AZ 85013, USA. Email: [email protected]

Red Flag for Cauda Equina Syndrome in Symptomatic Lumbar Disc Herniation

In a retrospective study, we sought to compare the clinical efficacy and postoperative magnetic resonance imaging (MRI) scans of minimally invasive (MI) and open (O) transforaminal lumbar interbody fusion (TLIF) in the treatment of cauda equina syndrome (CES) caused by lumbar disc herniation.In total, 116 patients with CES associated with disc herniation underwent decompression and stabilization surgery from January 2005 to January 2020 in a single-center study, and data were collected and retrospectively analyzed. The patients were divided into the O-TLIF and the MI-TLIF group. The perioperative clinical data and MRI assessment were used to assess the efficacy of the respective surgical methods preoperatively and with a minimum follow-up of 30 months.As expected, the O-TLIF group had statistically significantly longer surgery times and hospital stay, more bleeding, and perioperative surgical complications than the MI-TLIF group. At a minimum follow-up period of 30 months, the MI-TLIF group had significantly better Oswestry Disability Index, visual analog scale, and Short-Form-36, and neurologic CES symptoms than the O-TLIF group. The postoperative MRIs revealed a statistically significant difference in the multifidus muscle area in MI group compared with the O group.In patients with acute CES caused by disc herniation, MI-TLIF, with decreased disruption of paravertebral tissues and postoperative pain syndrome, results in earlier mobilization and rehabilitation with better long-term clinical outcomes compared with O-TLIF.

Does gender influence perioperative complications in transforaminal lumbar interbody fusion (TLIF) technique? A prospective multicentric cohort study

ObjectivesWe aimed to assess the effect of gender on the rate of perioperative and early postoperative complications after mono segment lumbar spine fusion using open transforaminal lumbar interbody fusion (TLIF) technique. Material and methodsWe conducted this prospective multicentric cohort study between January 2015 and February 2019. We included patients with degenerative disc disease, spondylolisthesis, primary or recurrent disc prolapse, and spinal stenosis. After the failure of other conservative measures, all patients underwent mono segment interbody fusion using an open TLIF approach. Patients were classified based on their biologically assigned gender. We used the SPSS software version 25 for statistical analysis. ResultsWe included a total of 335 patients (147 male and 188 female). Of them, a percentage of 55.8% aged between 30 and 50 years. The level of surgery was L4-S1 in 87.1% of the included cases. The female patients had longer operative time, more blood loss, and longer hospital stays than the male patients 110.9 vs. 104.6, 471.6 ccs vs. 441.8 ccs, 3.31 days vs. 2.12 days; p = 0.01, p = 0.23, and p < 0.001, respectively. Of the 54 reported complications, 38 were with female patients (p = 0.02). The most-reported complications were as follows: dural tear in 16 cases (5 male and 11 female), traction neuritis in 15 cases (4 male and 11 female), and wound infection in 9 cases (3 male and 6 female). ConclusionOur study showed patients' gender directly correlated with their operative time, length of hospital stay, as well as the rate of complication, with the female variable showing a trend of notable increase on all aforementioned items after mono segment TLIF surgery.

Safety of Lumbar Interbody Fusion Procedures for Degenerative Disc Disease: A Systematic Review With Network Meta-Analysis of Prospective Studies.

Study Design:A network meta-analysis.Objectives:Lumbar degenerative disc disease (LDDD) is an important issue in aging population, for which lumbar interbody fusion (LIF) is a feasible management in cases refractory to conservative therapy. There are various techniques available to perform LIF, including posterior (PLIF), transforaminal (TLIF), and anterior (ALIF) approaches. However, the comparative safety profile of these procedures remains controversial. Our study aimed to evaluate comparative adverse events of the LIF procedures in patients with LDDD.Methods:We searched 5 databases for relevant prospective cohort studies and randomized clinical trials. After quality assessments, we extracted neural, spinal, vascular, and wound events for conducting contrast-based network meta-analysis. Results were reported in risk ratio (RR), 95% confidence interval (CI), and surface under the cumulative ranking (SUCRA).Results:We identified 14 studies involving 921 participants with LDDD. Pooled result showed that open PLIF (OPLIF) leads to significantly higher overall adverse event rate than does open TLIF (OTLIF; RR = 3.43, 95% CI = 1.21-9.73). OTLIF confers the highest SUCRA in neural (78.7) and spinal (80.8) event rates. Minimally invasive TLIF has the highest SUCRA in vascular event (84.2), and minimally invasive PLIF has the highest SUCRA in wound event (88.1). No inconsistency or publication bias was detected in the results.Conclusions:Based on our results, perhaps OPLIF should be avoided in the management of LDDD due to the inferiority of overall complications. Specifically, TLIF seems to have the safest profile in terms of neural, spinal, and vascular events. Nevertheless, shared decision making is still mandatory when choosing the proper LIF procedure for patients with LDDD in clinical practice.

Minimally invasive transforaminal lumbar interbody fusion

Instrumented fusion of lumbar motion segments using aminimally invasive technique. Degenerative disc disease, segmental degeneration, degenerative spondylolisthesis, isthmic spondylolisthesis, pseudarthrosis, other spinal lumbar instabilities, disc prolapse, revision for failed back surgery syndrome, unilateral neuroforaminal stenosis, facet joint arthrosis. High-grade spondylolisthesis (Meyerding gradesIII/IV, spondyloptosis), bilateral nerve root compression, vertebral fractures, tumors, high-grade spinal instabilities, primary spinal deformities, multilevel pathologies. Ipsilateral minimally invasive approach using aself-retaining tubular retractor system, partial or complete facetectomy, insertion of pedicle screws, transforaminal lumbar interbody fusion (TLIF) cage insertion preserving nerve roots, fusion, contralateral insertion of pedicle screws using aminimally invasive or percutaneous technique. Mobilization with physiotherapy, followed by standing plain x‑ray examinations, clinical and radiological follow-up at 6-12weeks and 1year postoperatively. Fusion rates >90%, comparable to open TLIF. Complication rates lower than open TLIF. Shorter radiation exposure during surgery, lower blood loss. Less surgical trauma leads to shorter hospitalization time and earlier return-to-work. Oswestry Disability index (ODI) scores and visual analog scale (VAS) scores significantly decreased.

Comparison of Minimally Invasive Versus Open Transforaminal Interbody Lumbar Fusion.

Study Design:Narrative review.Objectives:In this review, we address the question of whether the literature supports the notion that minimally invasive transforaminal interbody fusion (MIS-TLIF) improves outcome as compared with open TLIF (open-TLIF). Short and long-term outcomes, fusion rate, and cost-effectiveness were reviewed.Methods:This is a narrative review using various databases. Open-TLIF and MIS-TLIF studies were included and posterior lumbar interbody fusion studies were excluded. A description of paramedian incision in surgical technique was essential to the definition of MIS-TLIF. The present review included 14 prospective observational studies and 6 randomized controlled trials.Results:With short-term outcomes, some studies indicate a better outcome with MIS-TLIF regarding intraoperative bleeding, hospital stay, time to ambulation, postoperative narcotic use, and time to resume work. Both MIS-TLIF and open-TLIF surgeries improved Oswestry Disability Index, back pain, and leg pain. Some studies show that MIS-TLIF resulted in lower back pain than open-TLIF. Radiation exposure was higher with MIS-TLIF. In the longer term, clinical outcomes were improved in both MIS and open TLIF groups. Fusion rates were more than 90% in both MIS-TLIF and open-TLIF. Cost-effectiveness and length of surgery had mixed results.Conclusions:The potential benefits of MIS-TLIF might be present in the early recovery period after surgery. Long-term outcomes were similar with both MIS-TLIF and open-TLIF.