Two-level Transforaminal Lumbar Interbody Fusion Research Articles

Transforaminal lumbar interbody fusion subsidence: computed tomography analysis of incidence, associated risk factors, and impact on outcomes.

The aims of this study were to 1) define the incidence of transforaminal lumbar interbody fusion (TLIF) interbody subsidence; 2) determine the relative importance of preoperative and intraoperative patient- and instrumentation-specific risk factors predictive of postoperative subsidence using CT-based assessment; and 3) determine the impact of TLIF subsidence on postoperative complications and fusion rates. All adult patients who underwent one- or two-level TLIF for lumbar degenerative conditions at a multi-institutional academic center between 2017 and 2019 were retrospectively identified. Patients with traumatic injury, infection, malignancy, previous fusion at the index level, combined anterior-posterior procedures, surgery with greater than two TLIF levels, or incomplete follow-up were excluded. Interbody subsidence at the superior and inferior endplates of each TLIF level was directly measured on the endplate-facing surface of both coronal and sagittal CT scans obtained greater than 6 months postoperatively. Patients were grouped based on the maximum subsidence at each operative level classified as mild, moderate, or severe based on previously documented < 2-mm, 2- to 4-mm, and ≥ 4-mm thresholds, respectively. Univariate and regression analyses compared patient demographics, medical comorbidities, preoperative bone quality, surgical factors including interbody cage parameters, and fusion and complication rates across subsidence groups. A total of 67 patients with 85 unique fusion levels met the inclusion and exclusion criteria. Overall, 28% of levels exhibited moderate subsidence and 35% showed severe subsidence after TLIF with no significant difference in the superior and inferior endplate subsidence. Moderate (≥ 2-mm) and severe (≥ 4-mm) subsidence were significantly associated with decreases in cage surface area and Taillard index as well as interbody cages with polyetheretherketone (PEEK) material and sawtooth surface geometry. Severe subsidence was also significantly associated with taller preoperative disc spaces, decreased vertebral Hounsfield units (HU), the absence of bone morphogenetic protein (BMP) use, and smooth cage surfaces. Regression analysis revealed decreases in Taillard index, cage surface area, and HU, and the absence of BMP use predicted subsidence. Severe subsidence was found to be a predictor of pseudarthrosis but was not significantly associated with revision surgery. Patient-level risk factors for TLIF subsidence included decreased HU and increased preoperative disc height. Intraoperative risk factors for TLIF subsidence were decreased cage surface area, PEEK cage material, bullet cages, posterior cage positioning, smooth cage surfaces, and sawtooth surface designs. Severe subsidence predicted TLIF pseudarthrosis; however, the causality of this relationship remains unclear.

Evaluation of the Fusion Rate and Safety of Escherichia coli-Derived rhBMP-2 in Transforaminal Lumbar Interbody Fusion for Patients with Degenerative Lumbar Disease: A Prospective, Multicenter, Single-Arm Trial.

Background: Few studies have documented the viability of E. coli-derived recombinant human bone morphogenetic protein-2 (rhBMP-2) in transforaminal lumbar interbody fusion (TLIF). This study aimed to assess the safety and fusion rate of rhBMP-2 in TLIF. Methods: The study was conducted as a prospective, multicenter, single-arm trial, and 30 patients needing one- or two-level TLIF were enrolled. Fusion rate was assessed using the 12-month interbody fusion rate on CT. Postoperative problems, including seroma, radiculitis, and ectopic bone formation, which have been documented as risks associated with rhBMP-2 in prior studies, were recorded. Results: The study demonstrated fusion outcomes in all instances at 52 and 104 weeks post-surgery. Significant improvements were observed in clinical outcomes, with ODI, SF-36, and VAS scores, all achieving statistical significance (p < 0.0001). No perioperative adverse events requiring reoperation were reported, and there were no incidences of seroma, radiculitis, cage migration, grafted bone extrusion, postoperative neurologic deficit, or deep wound infection. Conclusions: The study demonstrates the high safety and efficacy in inducing bone fusion of E. coli-derived rhBMP-2 in TLIF, with a notable absence of adverse postoperative complications. Trial registration: This study protocol was registered at Korea Clinical Research Information Service (number identifier: KCT0004738) on July 2020.

Adhesive surface electrodes versus needle-based neuromonitoring in lumbar spinal surgery.

The relative safety and more widespread utility of an adhesive surface electrode-based neuromonitoring (ABM) system may reduce the time and cost of traditional needle-based neuromonitoring (NBM). This retrospective cohort review included one- and two-level transforaminal lumbar interbody fusion procedures (2019-2023). The primary variables studied included were time (in minutes) from patient entry into the operating room (OR) to incision, time from patient entry into the OR to closure, and time from incision to closure. Univariate and bivariate analyses were performed to compare the outcomes between the ABM (31 patients) and NBM (51 patients) modalities. We found no significant differences in the time from patient entry into the OR to incision (ABM: 71.8, NBM: 70.3, P = 0.70), time from patient entry into the OR to closure (ABM: 284.2, NBM: 301.7, P = 0.27), or time from incision to closure (ABM: 212.4, NBM: 231.4, P = 0.17) between the two groups. Further, no patients from either group required reoperation for mal-positioned instrumentation, and none sustained a new postoperative neurological deficit. The ABM approach did, however, allow for a reduction in neurophysiologist-workforce and neuromonitoring costs. The introduction of the ABM system did not lower surgical time but did demonstrate similar efficacy and clinical outcomes, with reduced clinical invasiveness, neurophysiologist-associated workforce, and overall neuromonitoring cost compared to NBM.

Postoperative Sclerotic Modic Changes After Transforaminal Lumbar Interbody Fusion: The Prevalence, Risk Factors, and Impact on Fusion.

A retrospective cohort study. This study aimed to assess postoperative sclerotic modic changes (MCs) following transforaminal lumbar interbody fusion for lumbar degenerative disc disease, investigating their prevalence, risk factors, and association with clinical outcomes. Sclerotic MCs may occur in patients with lumbar degenerative disc disease after lumbar interbody fusion. The incidence and characteristics of postoperative sclerotic MCs, as well as their clinical impact, are unknown. The study included 467 patients (510 levels) who underwent single or two-level transforaminal lumbar interbody fusion surgery, divided into a postoperative sclerotic MC group (60 patients, 66 levels) and a non-MC group (407 patients, 444 levels). The time of development and location of postoperative sclerotic MCs, fusion rate, cage subsidence, bilateral process decompression, and cross-link usage were recorded. Preoperative, postoperative, and follow-up visual analogue scale and Oswestry disability index scores were collected. Multivariable logistic regression was used to evaluate factors associated with the development of postoperative sclerotic MCs. The prevalence of postoperative sclerotic MCs was 12.8%. The postoperative sclerotic MC group had a higher body mass index (BMI). The postoperative sclerotic MC group demonstrated a fusion rate of 47%, significantly lower than that of the non-MC group (71%) at six months post-operation. At final follow-up, the fusion rate in the postoperative sclerotic MC group was 62%, significantly lower than that of the non-MC group (86%). Postoperative visual analogue scale and Oswestry disability index scores were significantly higher in the group with postoperative sclerotic MCs. BMI and osteoporosis were significantly associated with the development of postoperative sclerotic MCs. Postoperative sclerotic MCs generally appear within the first year after surgery, with a prevalence of 12.8%. The presence of postoperative sclerotic MCs can adversely impact postoperative outcomes. To prevent postoperative sclerotic MCs, the authors postulate extending the immobilization period with external bracing and improving the management of BMI and osteoporosis in the perioperative time window.

Comparing Cortical Bone Trajectory and Traditional Pedicle Screws in Transforaminal Lumbar Interbody Fusion: A Retrospective Cohort Study of One-Year Outcomes.

This is a retrospective study of consecutive patients undergoing transforaminal lumbar interbody fusion (TLIF) at a single institution. The objective of this study was to compare the long-term results associated with cortical bone trajectory (CBT) and traditional pedicle screw (TPS) via posterolateral approach in TLIF. Consecutive patients treated from November 2014 to March 2019 were included in the CBT TLIF group, while consecutive patients treated from October 2010 to August 2017 were included in the TPS TLIF group. Inclusion criteria comprised single-level or two-level TLIF for degenerative spondylolisthesis with stenosis and at least one year of clinical and radiographic follow-up. Variables of interest included pertinent preoperative, perioperative, and postoperative data. Non-parametric evaluation was performed using the Wilcoxon test. Fisher's exact test was used to assess group differences for nominal data. Overall, 140 patients met the inclusion criteria; 69 patients had CBT instrumentation (mean follow-up 526 days) and 71 patients underwent instrumentation placement via TPS (mean follow-up 825 days). Examination of perioperative and postoperative outcomes demonstrate comparable results between the groups with perioperative complications, length of stay, discharge destination, surgical revision rate, and fusion rates all being similar between groups (p = 0.1; p = 0.53; p = 0.091; p = 0.61; p = 0.665, respectively). CBT in the setting of TLIF offer equivalent outcomes to TPS with TLIF at both short- and long-term intervals of care.

Evaluation of the efficacy and safety of Escherichia coli-derived recombinant human bone morphogenetic protein-2 in transforaminal lumbar interbody fusion to treat degenerative spinal disease: a protocol of prospective, randomized controlled, assessor-blinded, open-label, multicenter trial

BackgroundRecombinant human bone morphogenetic protein-2 (rhBMP-2) has been widely used as an alternative bone graft in spine fusion surgery. However, clinical outcome such as effects and complications has not yet been revealed for transforaminal lumbar interbody fusion (TLIF). Although previous studies have reported some results, the evidence is weak. Therefore, the purpose of this trial is to evaluate the effectiveness and safety of Escherichia coli-derived rhBMP-2 combined with hydroxyapatite (HA) in TLIF.MethodsThis trial is designed as a prospective, assessor-blinded, open-label, multicenter, randomized controlled study. Participants will be recruited from six tertiary teaching hospitals. All randomized participants will be undergoing one- or two-level TLIF with rhBMP-2 (77 participants) as the active experimental group or with an auto-iliac bone graft (77 participants) as the control group. The primary interbody fusion rate outcome will be evaluated using computed tomography (CT) 12 months after surgery. The secondary outcomes will be as follows: clinical outcomes (visual analog scale score, EuroQol-5-dimensions-5-level score, Oswestry Disability Index score, and some surgery-related variables) and adverse effects (radiculitis, heterotrophic ossification, endplate resorption, and osteolysis). Radiological outcomes will be evaluated using simple radiography or CT. All outcomes will be measured, collected, and evaluated before surgery and at 12, 24, and 52 weeks postoperatively.DiscussionThis study will be the primary of its kind to evaluate the effectiveness and safety of E. coli-derived rhBMP-2 with HA in one- or two-level TLIF. It is designed to evaluate the equivalence of the results between rhBMP-2 with HA and auto-iliac bone graft using an appropriate sample size, assessor-blinded analyses, and prospective registration to avoid bias. This study will set up clear conclusions for using E. coli-derived rhBMP-2 with HA in TLIF.Trial registration: This study protocol was registered at Korea Clinical Research Information Service (https://cris.nih.go.kr; number identifier: KCT0005610) on 19 November 2020. And protocol version is v1.1, January 2022.

Clinical comparison of three-dimensional exoscope vs. operative microscope in transforaminal lumbar interbody fusion: A retrospective case-control study.

Here, we sought to determine the safety and feasibility of three-dimensional exoscope (3D EX). We compared data on surgery, complications, postoperative drainage, hematology, and clinical outcomes in the group that underwent transforaminal lumbar interbody fusion (TLIF) using an operative microscope (OM) relative to those treated using 3D EX. We retrospectively reviewed records on 74 patients who underwent one- or two-level TLIF from August 2019 to October 2020. Repeated measures analysis of variance was used to compare pre- and post-operative visual analogue scale (VAS) scores and oswestry disability index (ODI). We used analysis of covariance to compare pre- and post-operative erythrocyte count (RBC), hemoglobin (Hb), and hematocrit (Hct). Independent sample t-tests was used to compare postoperative drainage volume, total blood loss (TBL), visible blood loss (VBL) and hidden blood loss (HBL). There were no significant differences in VAS and ODI scores between the two groups at all time points (all p > 0.05). RBC and HBL did not differ significantly between the two groups (all p > 0.05). There were significant differences in postoperative drainage volume,TBL, Hb, and Hct values when using 3D EX relative to OM in two-level TLIF (all p < 0.05), but not for one-level TLIF (all p > 0.05). The two groups differed significantly with regards to VBL when used for one- or two-level TLIF (all p < 0.05). Our data show that 3D EX is a suitable alternative to OM in TLIF. Relative to OM, 3D EX has important strengths in reducing perioperative bleeding in two-level TLIF.

Robotics Reduces Radiation Exposure in Minimally Invasive Lumbar Fusion Compared With Navigation.

Retrospective cohort. To compare robotics and navigation for minimally invasive elective lumbar fusion in terms of radiation exposure and time demand. Although various studies have been conducted to demonstrate the benefits of both navigation and robotics over fluoroscopy in terms of radiation exposure, literature is lacking in studies comparing robotics versus navigation. Patients who underwent elective one-level or two-level minimally invasive transforaminal lumbar interbody fusion (TLIF) by a single surgeon using navigation (Stryker SpineMask) or robotics (ExcelsiusGPS) were included (navigation 2017-2019, robotics 2019-2021, resulting in prospective cohorts of consecutive patients for each modality). All surgeries had the intraoperative computed tomography workflow. The two cohorts were compared for radiation exposure [fluoroscopy time and radiation dose: image capture, surgical procedure, and overall) and time demand (time for setup and image capture, operative time, and total operating room (OR) time]. A total of 244 patients (robotics 111, navigation 133) were included. The two cohorts were similar in terms of baseline demographics, primary/revision surgeries, and fusion levels. For one-level TLIF, total fluoroscopy time, total radiation dose, and % of radiation for surgical procedure were significantly less with robotics compared with navigation (20 vs. 25s, P <0.001; 38 vs. 42mGy, P =0.05; 58% vs. 65%, P =0.021). Although time for setup and image capture was significantly less with robotics (22 vs. 25min, P <0.001) and operative time was significantly greater with robotics (103 vs. 93min, P <0.001), there was no significant difference in the total OR time (145 vs. 141min, P =0.25). Similar findings were seen for two-level TLIF as well. Robotics for minimally invasive TLIF, compared with navigation, leads to a significant reduction in radiation exposure both to the surgeon and patient, with no significant difference in the total OR time.

Radiographic and clinical outcomes in one- and two-level transforaminal lumbar interbody fusions: a comparison of bullet versus banana cages.

The aim of this study was to determine whether cage morphology influences clinical and radiographic outcomes following short-segment transforaminal lumbar interbody fusion (TLIF) procedures. The authors retrospectively reviewed one- and two-level TLIFs at a single tertiary care center between August 2012 and November 2019 with a minimum 1-year radiographic and clinical follow-up. Two cohorts were compared based on interbody cage morphology: steerable "banana" cage or straight "bullet" cage. Patient-reported outcome measures (PROMs), radiographs, and complications were analyzed. A total of 135 patients with 177 interbody levels were identified; 45 patients had 52 straight cages and 90 patients had 125 steerable cages. Segmental lordosis increased with steerable cages, while it decreased with straight cages (+3.8 ± 4.6 vs -1.9 ± 4.3, p < 0.001). Conversely, the mean segmental lordosis of adjacent lumbar levels decreased in the former group, while it increased in the latter group (-0.52 ± 1.9 vs +0.52 ± 2.1, p = 0.004). This reciprocal relationship results in global sagittal parameters, including pelvic incidence minus lumbar lordosis and lumbar distribution index, which did not change after surgery with either cage morphology. Multivariate analysis confirmed that steerable cage morphology, anterior cage positioning, and less preoperative index-level segmental lordosis were associated with greater improvement in index-level segmental lordosis. PROMs were improved after surgery with both cage types, and the degree of improvement did not differ between cohorts (p > 0.05). Perioperative and radiographic complications were similar between cohorts (p > 0.05). Overall reoperation rates, as well as reoperation rates for adjacent-segment disease within 2 years of surgery, were not significantly different between cohorts. Steerable cages are more likely to lie within the anterior disc space, thus increasing index-level segmental lordosis, which is accompanied by a reciprocal change in segmental alignment at the adjacent lumbar levels. The converse relationship occurs for straight cages, with a kyphotic change at the index levels and reciprocal lordosis occurring at adjacent levels.

Novel Simultaneous Two-Surgeon Approach for Two Level Minimally Invasive Transforaminal Lumbar Interbody Fusion: Application of a Tubular-based Camera

Introduction Continuing efforts in spine research and development are essential to establish, maintain and evolve minimally invasive surgery (MIS). MIS applications in spine surgery are the result of a persistent and ongoing development of smart technologies, along with meticulous surgical training practices and the improvement of instruments and techniques. Thus, MIS approaches to the spine can benefit from novel technologies that reduce fluoroscopy utilization, operative time, surgeon fatigue, while potentially increasing cooperative strategies for challenging and multi-level surgeries. Clinical Presentation We describe two cases with the novel utilization of the tubular-based camera system to allow for two surgeons to work simultaneously in treating a patient that required a two-level transforaminal lumbar interbody fusion (TLIF) surgery for degenerative spondylosis at L4-5 and L5-S1. Conclusion In this case specifically, this approach was made possible with a tubular-based sterile camera which allowed for the two surgeons to work comfortably in concert, without encountering issues of visualization, collisions, and fatigue. With specific focus on radiation, operative time, and visualization, this technique specifically addresses some of the shortfalls of MIS spine surgery procedures, and could be considered as a first-line approach for two-level MIS TLIF surgeries.

Preoperative Radiographic Prediction Tool for Early Postoperative Segmental and Lumbar Lordosis Alignment After Transforaminal Lumbar Interbody Fusion.

ObjectiveTransforaminal lumbar interbody fusion (TLIF) is a common approach and results in varying degrees of lordosis correction. The purpose of this study is to determine preoperative radiographic spinopelvic parameters that predict change in postoperative segmental and lumbar lordosis after TLIF.Materials & MethodsThis study is a single surgeon retrospective review of one-level and two-level TLIFs from L3-S1. All patients underwent bilateral facetectomies, 10 mm TLIF cage (non-lordotic) insertions, and bilateral pedicle screw-rod construct placements. Pre- and post-operative X-rays were assessed for preoperative segmental lordosis (SL), lumbar lordosis (LL), and pelvic incidence (PI). Univariate and multi-predictor linear regression analyses were performed to determine the relationships between preoperative radiographic findings and change in early postoperative segmental and lumbar lordosis.ResultsNinety-seven patients contributing 128 intervertebral segments were examined. The mean change in SL after TLIF was 7.3 (range: 0.10-28.9°, SD 6.39°). The mean change in LL after TLIF was 5.5˚ (range: -14.8-39.2°, standard deviation (SD) 7.16°). Greater preoperative LL predicted less postoperative LL correction, while greater preoperative PI predicted more postoperative SL and LL correction. Greater anterior disk height was noted to be associated with a decreased change in SL (∆SL). An annular tear on preoperative magnetic resonance imaging (MRI) predicted a 2.7° decrease in ∆SL. A Schmorl's node on preoperative MRI predicted a 4.0° decrease in change in LL (∆LL).ConclusionsA greater preoperative lordosis and a lower spinopelvic mismatch lessen the potential for an increase in the postoperative SL and LL after a TLIF, which is likely due to a ‘ceiling’ effect of an otherwise optimized spinal alignment. A greater anterior disk height and the presence of an annular tear are associated with decreased ∆SL.

Comparing hyperlordotic and standard lordotic cages for achieving segmental lumbar lordosis during transforaminal lumbar interbody fusion in adult spinal deformity surgery.

Few studies directly compare the effect of interbody cages with different degrees of lordosis in producing segmental lumbar lordosis (SLL) in the transforaminal lumbar interbody fusion (TLIF) procedure. Thus, we aimed to investigate changes in SLL in hyperlordotic cages compared to standard lordotic cages in open TLIF procedures. Thirty-eight consecutive patients who received open TLIF procedures performed by a single surgeon between 2017 and 2018 were reviewed. Twenty patients had "hyperlordotic cages" (20° lordosis), while 18 patients had "standard lordotic cages" (6° lordosis). Twenty-three patients had one-level TLIF procedures and 15 had two-level TLIF. Standard radiographic measurements, including SLL were assessed preoperatively, postoperatively, and at 1-year follow-up. SLL was measured from the superior endplate of the cephalad vertebra to the inferior endplate of the caudal vertebra. Changes in SLL were compared using Student's and paired t-tests. In one- and two-level open TLIF, both hyperlordotic and standard lordotic cages produced significant improvement in SLL. Among those receiving a one-level TLIF, SLL increased 7.8° (P=0.024) in those with standard lordotic cages; it increased 8.2° (P=0.020) in those with hyperlordotic cages. Among those receiving a two-level TLIF, SLL increased 13.9° (P=0.032) in those with standard lordotic cages; it increased 8.8° (P=0.023) in those with hyperlordotic cages. However, the improvement in SLL was not significantly different between the two cage types in either one or two-level TLIF procedures (P=0.917, P=0.389). At 1-year follow-up, there was no significant change in SLL, among standard lordotic and hyperlordotic cages (P=0.501, P=0.781). Although it is theorized that hyperlordotic cages would increase SLL during open TLIF procedures more than standard lordotic cages, our data failed to demonstrate that. As our study examined cases performed by a single surgeon immediately before and after adoption of these lordotic cages, it is likely that surgical technique is of equal or greater importance in improving SLL than the amount of lordosis designed into interbody cages.

Bone Metabolism in the Healing Process of Lumbar Interbody Fusion: Temporal Changes of Bone Turnover Markers.

Prospective longitudinal study. The aim of this study was to evaluate temporal changes of bone turnover markers (BTMs) after lumbar spinal fusion in patients without osteoporosis. Radiological studies are the standard method to monitor bony fusion, but they do not allow a timely assessment of bone healing. BTMs react rapidly to changes in bone metabolism during fusion process and could be an additional tool to monitor this process. A total of 78 nonosteoporosis patients who had undergone one- or two-level transforaminal lumbar interbody fusion were included. Fusion status was assessed using computed tomography sagittal and coronal images. Serum levels of bone-specific alkaline phosphatase (BAP), procollagen type 1 amino-terminal propeptide (P1NP), and osteocalcin (OC) were measured to assess bone formation, and tartrate-resistant acid phosphatase 5b (TRACP-5b) was measured to assess bone resorption. Serum samples were obtained before surgery and at 1, 2, 4, 8, 13, 26, 39, and 52 weeks after surgery. A solid fusion was achieved in 71 of 78 patients (91%), and seven patients resulted in pseudarthrosis. In the fusion group, the level of all BTMs once decreased at 1 postoperative week. Then, BAP and P1NP reached a peak at 4 weeks after surgery, and TRACP-5b and OC peaked at 8 weeks. Thereafter, the level of P1NP and TRACP-5b gradually got closer to the baseline over a year, and BAP kept high until 52 postoperative weeks. In the pseudarthrosis group, peak level of BTMs was significantly higher and the increased level of BAP and P1NP was kept until 52 weeks. The present study demonstrated dynamics of BTMs after lumbar spinal fusion in patients without osteoporosis. These normal population data contribute as a baseline to evaluate the effect of osteogenic agents on bone metabolism after spinal fusion.Level of Evidence: 2.

267. The impact of preventative multimodal analgesia on postoperative opioid requirement and pain control in patients undergoing lumbar fusions

BACKGROUND CONTEXT Preventive multimodal analgesia (PMA) addresses multiple sources and pathways of acute and chronic pain by interfering with peripheral and central sensitization and should provide a way to achieve safer and more effective pain management with reduced opioid medication use. PURPOSE The main objectives of this study were to determine the impact of PMA on postoperative opioid requirements and analgesic effectiveness in patients undergoing lumbar fusion surgery. STUDY DESIGN/SETTING A prospective observational study with a historical reference group was performed. PATIENT SAMPLE The study compared postoperative opioid requirement and analgesic effect in a total of 103 patients undergoing elective, one- or two-level transforaminal lumbar interbody fusion (TLIF) surgeries for symptomatic lumbar degenerative disc disease. The PMA patient group included 52 consecutive patients who received 1000 mg of acetaminophen, 300 – 900 mg of gabapentin, and 200 – 400 mg of celecoxib 1 hour before the procedure. The reference group included 51 patients who received 15 mg of morphine-equivalent dose (MED) preoperatively. OUTCOME MEASURES Postoperative opioid requirement and pain scores. METHODS Multiple linear regression was used to evaluate the influence of PMA on pain, MED and acetaminophen use over 4 postoperative days (PODs), while controlling for all variables likely to influence these outcomes, including age, gender, baseline opioid use, duration of surgery, postoperative intrathecal morphine use and administration of muscle relaxants and anticonvulsants. RESULTS The differences in opioid requirement and postoperative pain scores were statistically significant on all four postoperative days. The effect size varied from -0.54 to -0.99 for the postoperative opioid requirement and from -0.59 to -1.16 for postoperative pain indicating that these measures were reduced by about ½ to 1 standard deviation in the PMA patient group. CONCLUSIONS PMA is a highly effective method for postoperative pain management in patients undergoing lumbar fusion surgeries, which not only improves pain control, but also reduces opioid requirement. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

218. Preoperative opioid use is associated with increased readmission and reoperation rates following lumbar decompression, instrumentation and fusion

BACKGROUND CONTEXT The prescription opioid epidemic and widespread use of narcotic medications has introduced new challenges when treating patients undergoing spine surgery. Recent studies in general surgery, spine and total joint arthroplasty literature demonstrate associations between preoperative opioid use and increased emergency department visits, readmission rates, revision rates and risk of developing chronic opioid dependence. Researchers estimate that 33-70% of patients undergoing spinal surgery use opioids preoperatively. Given the prevalence of preoperative opioid consumption among patients undergoing spine surgery, further research is needed to quantify and stratify perioperative risks in this patient population. PURPOSE The purpose of this study is to compare outcomes of primary one- or two-level lumbar decompression, instrumentation and fusion based on preoperative opioid consumption habits. STUDY DESIGN/SETTING A retrospective chart review was performed on patients who underwent one- to two-level posterior lumbar decompression, instrumentation and fusion from two spine surgeons at a single, tertiary referral center from 2013-2017. PATIENT SAMPLE Inclusion criteria included all patients who underwent a primary one- to two-level decompression (laminectomy or laminotomy) with posterior instrumentation, one- or two-level intertransverse arthrodesis (PLF), one- or two-level transforaminal lumbar interbody fusion (TLIF) or one- or two-level posterior lumbar interbody fusion (PLIF). Exclusion criteria included patients undergoing revision surgery, patients with concomitant malignancy or surgery for neoplastic disease, three- or more-level surgery, anterior or lateral (direct or oblique) interbody fusions, traumatic injuries (acute fractures or ligamentous instability) or other concurrent procedures. Patient opioid use was obtained from electronic medical records (Epic Systems Corporation, Verona, WI) including medication history and preoperative clinical documentation. Patients were divided into chronic opioid therapy (COT; >6 months), acute users (0-6 months) and opiate-naive based on their preoperative opioid usage. OUTCOME MEASURES Primary endpoints included readmission rates within 1 year and reoperation rates within 2 years. METHODS A retrospective chart review was conducted from 2013-2017 and patients who met the inclusion criteria were studied. Patients were divided into three groups based on their aforementioned preoperative opioid consumption status. Demographic information (age, BMI, sex and ethnicity), smoking status and primary outcome measures were identified and recorded based on documentation in the electronic medical record. RESULTS A total of 93 patients met the inclusion and exclusion criteria (57 PLF, 31 TLIF and 5 PLIF). Demographics characteristics were similar between all three groups. Thirty-three patients (35.5%) required COT, 31 patients (33.3%) utilized acute opioid therapy and 29 patients (31.2%) remained opioid naive. Current or former smokers were more likely to utilize acute or COT than never smokers (86% vs 59%; p=0.005). Readmission rates within 1 year for patients in the COT, acute and opioid naive groups were 50%, 41.7% and 8.3%, respectively (p=0.0115). Reoperation rates within 2 years for patients in the COT, acute and opioid naive groups were 54.2%, 33.3% and 12.5%, respectively (p = 0.033). CONCLUSIONS Long-term opiate use is associated with an increased risk for readmission within 1 year and revision within 2 years following a primary posterior decompression, instrumentation and fusion. Numerous data base studies have demonstrated similar, suboptimal outcomes for patients on preoperative opioid therapy compared to nonusers. This retrospective chart review corroborates the findings of these previous studies. Given the prevalence of narcotic usage in the US population, physicians should continue to educate acute or chronic opioid users about increased risk of readmission and revision associated with lumbar decompression and fusion. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

The Impact of Preventative Multimodal Analgesia on Postoperative Opioid Requirement and Pain Control in Patients Undergoing Lumbar Fusions

Abstract INTRODUCTION Preventive multimodal analgesia (PMA) addresses multiple sources and pathways of acute and chronic pain by interfering with peripheral and central sensitization and should provide a way to achieve safer and more effective pain management with reduced opioid medication use. The main objectives of this study were to determine the impact of PMA on postoperative opioid requirements and analgesic effectiveness in patients undergoing lumbar fusion surgery. METHODS A prospective observational study with a historical reference group was performed. The study compared the postoperative opioid requirement and analgesic effect in a total of 103 patients undergoing elective, one- or two-level transforaminal lumbar interbody fusion (TLIF) surgeries for symptomatic lumbar degenerative disc diseases. The PMA patient group included 52 consecutive patients who received 1000 mg of acetaminophen, 300 consecutive patients receiving 900 mg of gabapentin, and 200 consecutive patients receiving 400 mg of celecoxib 1 h before the procedure. The reference group included 51 patients who received 15 mg of morphine-equivalent dose (MED) preoperatively. Multiple linear regression was used to evaluate the influence of PMA on pain, MED, and acetaminophen use over 4 postoperative days (PODs), while controlling for all variables likely to influence these outcomes, including age, gender, baseline opioid use, duration of surgery, postoperative intrathecal morphine use, and administration of muscle relaxants and anticonvulsants. RESULTS The differences in opioid requirement and postoperative pain scores were statistically significant on all 4 postoperative days. The effect size varied from –0.54 to –0.99 for the postoperative opioid requirement and from –0.59 to –1.16 for postoperative pain, indicating that these measures were reduced by about ½ to 1 standard deviation in the PMA patient group. CONCLUSION PMA is a highly effective method for postoperative pain management in patients undergoing lumbar fusion surgeries, which not only improves pain control, but also reduces the opioid requirement.

One- or Two-Level Transforaminal Lumbar Interbody Fusion without Closed-Suction Wound Drainage

Background Data: Although many surgeons stopped using closed-suction drainage following simple spine decompression surgery, there is still debate regarding the necessity of wound drainage in more extensive lumbar spine surgical procedures. Purpose: To estimate the advantages and disadvantages of performing one- or two-level transforaminal lumbar interbody fusion (TLIF) without closed-suction drainage. Study Design: Retrospective clinical cohort study. Patients and Methods: The Fast-Track technique was performed in 36 consecutive TLIF surgeries between January and September 2016 without using wound drainage. Twenty-eight patients were females and 8 were males. Thirty patients had single-level TLIF and 6 double-level TLIF. The results of these patient series were retrospectively analyzed. The variables that were reviewed included blood transfusion, postoperative temperature, postoperative pain and the use of opiates during hospital stay, duration of surgery, duration of hospital stay, and incidence of postoperative complications such as neurological deficit, hematoma, postoperative wound infection, and revision surgery. Results: There was no postoperative allogenic blood transfusion; the patients did not develop postoperative neurological deficit; there were no cases of surgical revision as a result of significant postoperative hematoma or infection. There were two cases (5.5%) of revision surgery due to persistent CSF leakage from the wound. Four patients (11.1%) developed serous discharge from the wound, which was treated conservatively with frequent dressing and antibiotics. Four patients (11.1%) developed transient postoperative fever. The mean pain score in the first 2 days after surgery assessed by the Visual Analogue Score (VAS) was 6.1 points, and additional opiate in the first 2 postoperative days was mandatory in 30 patients (83.3%). Conclusion: Performing one- or two-level lumbar decompression and fusion without closed-suction wound drainage did not increase the rate postoperative infection or hematoma formation. Additionally, none of our patients required postoperative blood transfusion. (2018ESJ168)

Thursday, September 27, 2018 1:05 PM–2:05 PM Lumbar Spine Surgery: What You Need to Know: 114. No difference in reoperation rates or outcomes for a two-level posterolateral fusion augmented with single- versus two-level transforaminal lumbar interbody fusion

BACKGROUND CONTEXT Interbody devices (IBD) are being increasingly utilized during lumbar fusions with reported benefits, when compared to posterolateral fusion (PLF) alone, including increased fusion rates, increased neuroforaminal height, and the potential for improved sagittal alignment. Moreover, use of IBD has been shown to reduce reoperation rates compared to PLF alone. Although excellent outcomes have been demonstrated for single level transforaminal lumbar interbody fusion (TLIF), outcomes for single level TLIF in the setting of multiple level PLF are unknown. Some have suggested that a single level TLIF in the setting of a two level PLF may lead to increased pseudarthrosis at the level without an IBD, perhaps secondary to differences in stiffness at those levels in the setting of a developing fusion. PURPOSE We aim to determine whether there are differences in reoperation rate and outcomes for patients undergoing two level PLF augmented by a TLIF at only one of the levels vs at both levels. STUDY DESIGN/SETTING Retrospective, single institution, multi-surgeon patient cohort. PATIENT SAMPLE From September 2012 through September 2017, 416 patients were identified who underwent two level PLF with a TLIF at either one of those levels (n=183) or at both (n=233) with greater than one year follow-up. The two level TLIF group was significantly younger than the single level TLIF group (60.2 vs. 63.7, p=0.001), had a significantly lower Charleston Comorbidity Index (0.32 vs. 1.21, p OUTCOME MEASURES Primary outcome was reoperation rate with secondary outcomes including surgical parameters (estimated blood loss [EBL], OR time, length of stay [LOS]) and patient reported outcome measures (ODI, SF-12). METHODS T-tests were used to compare the cohorts for continuous variables and Chi square tests were used to compare the groups on categorical variables. RESULTS The one level and two level TLIF groups underwent 24 reoperations for 25 complication types and 24 reoperations for 27 complication types, respectively. Although the number of overall reoperations was not significantly different (p>0.05), among the reoperation types, there were significantly more reoperations for adjacent segment disease in the two level group compared to the one level group (19 vs. 12, p=0.04). There was no difference in reoperation for pseudarthrosis between the groups (p>0.05). Although the two level group had a higher EBL (p=0.002), they had an overall shorter LOS (p=0.003) (likely because they were younger and healthier to start). Although both groups experienced significant improvements in ODI (p CONCLUSIONS For patients undergoing two level PLF in the setting of a TLIF, using a TLIF at one vs both levels does not seem to influence reoperation rates or outcomes. However, reoperation rates for adjacent segment disease are increased in the setting of a two level PLF augmented by two TLIFs. FDA DEVICE/DRUG STATUS All devices were FDA approved and used as instructed.

Long-term outcomes of transforaminal lumbar interbody fusion in patients with spinal stenosis and degenerative scoliosis

Background ContextPatients with spinal deformity may present with complaints related to either the deformity itself or the manifestations of the coexisting spinal stenosis. There are reports of successful management of lumbar pathology in the absence of global sagittal or coronal imbalance, with limited decompression and fusion, addressing only the symptomatic segment. PurposeOur study examined the long-term outcomes of transforaminal lumbar interbody fusion (TLIF), a less extensive procedure, based on the experience of the senior author over the past 10 years. Study Design/SettingThis was a retrospective study of symptomatic lumbar spinal stenosis and spinal deformity managed by one surgeon at The Cleveland Clinic since 2003. Patient SampleForty-one patients were included in the study. Outcome MeasuresThe present study measures the long-term clinical functional outcomes of these patients through EQ-5D (EuroQol five dimensions questionnaire), PHQ-9 (Patient Health Questionnaire), and PDQ (Pain Disability Questionnaire) forms, along with documented radiographic parameters and Charlson Comorbidity Index (CCI). MethodsThere were no funding or potential conflicts of interest associated biases in the present study. Patients with symptomatic lumbar spinal stenosis with neutral global alignment in the sagittal and coronal planes and symptomatic stenosis at the deformity level were treated by limited fusion and TLIF, and had a follow-up period of at least 5 years. Excluded were patients under 18 years of age, had more than three levels of fusion, and had an active spinal malignancy or recent spinal trauma. The grouping variables were curve magnitude, revision surgeries, and TLIF levels. Clinical outcomes were compared in all the grouping variables. Analysis of variance (ANOVA) and chi-square tests were utilized; p<.05 was considered statistically significant. ResultsThe average age and follow-up period were 66±10 and 7.5 years, respectively. There was no statistical difference between patients with curves measuring between 10° and 20° and greater than 20° for EQ-5D, PHQ-9, and PDQ. Patients had worse PDQ data with larger curves compared with smaller curves at both 5 years and final follow-up. Although there was no statistical significance between preoperative coronal curve magnitude and revision surgeries, patients with curves greater than 20° had higher rates of revision surgeries (75%; p=.343) in the global lumbar curve deformity group. Although there was no statistical significance for patients who underwent revision surgeries,those patients had low PHQ-9 values at the final follow-up (p=.09). The revision surgery rate was 48% in one-level TLIF and 18% in two-level TLIF. Moderate pain disability scores were noticed for one-level TLIF patients (mean=75) compared with two-level TLIF patients (mean=27) at the final follow-up, and approached statistical significance in this comparison (p=.06). ConclusionAlthough this topic has a limited audience to spinal deformity surgeons, the prevalence of patients who present with adult spinal deformities has been increasing. Short segment fusion, in the setting of modest spinal deformity, is a reasonable and safe option. Further study on the concept of short segment fusions in the growing patient population is required as more comprehensive fusions do have noted complication rates, and a compromise must be reached between the extent of surgery that is enough to provide pain relief and disability and the degree of surgery that is too much to be tolerated in terms of complication rates.

Biomechanical analysis of lateral interbody fusion strategies for adjacent segment degeneration in the lumbar spine

Background ContextSurgical treatment of symptomatic adjacent segment disease (ASD) typically involves extension of previous instrumentation to include the newly affected level(s). Disruption of the incision site can present challenges and increases the risk of complication. Lateral-based interbody fusion techniques may provide a viable surgical alternative that avoids these risks. This study is the first to analyze the biomechanical effect of adding a lateral-based construct to an existing fusion. PurposeThe study aimed to determine whether a minimally invasive lateral interbody device, with and without supplemental instrumentation, can effectively stabilize the rostral segment adjacent to a two-level fusion when compared with a traditional posterior revision approach. Study Design/SettingThis is a cadaveric biomechanical study of lateral-based interbody strategies as add-on techniques to an existing fusion for the treatment of ASD. MethodsTwelve lumbosacral specimens were non-destructively loaded in flexion, extension, lateral bending, and torsion. Sequentially, the tested conditions were intact, two-level transforaminal lumbar interbody fusion (TLIF) (L3–L5), followed by lateral lumbar interbody fusion procedures at L2–L3 including interbody alone, a supplemental lateral plate, a supplemental spinous process plate, and then either cortical screw or pedicle screw fixation. A three-level TLIF was the final instrumented condition. In all conditions, three-dimensional kinematics were tracked and range of motion (ROM) was calculated for comparisons. Institutional funds (<$50,000) in support of this work were provided by Medtronic Spine. ResultsThe addition of a lateral interbody device superadjacent to a two-level fusion significantly reduced motion in flexion, extension, and lateral bending (p<.05). Supplementing with a lateral plate further reduced ROM during lateral bending and torsion, whereas a spinous process plate further reduced ROM during flexion and extension. The addition of posterior cortical screws provided the most stable lateral lumbar interbody fusion construct, demonstrating ROM comparable with a traditional three-level TLIF. ConclusionsThe data presented suggest that a lateral-based interbody fusion supplemented with additional minimally invasive instrumentation may provide comparable stability with a traditional posterior revision approach without removal of the existing two-level rod in an ASD revision scenario.