Lumbar Spinal Fusion Procedures Research Articles

Effective use of actifuse shape in spinal fusion: A retrospective chart review

Introduction: This study aimed to assess the safety and clinical performance of Actifuse Shape for spine surgery. Method: A retrospective real-world data study was conducted in two research sites in the U.S. Patient medical records had to show evidence of implantation with Actifuse Shape in 1-2 levels or 2 or more levels cervical (C2 or lower), in either posterolateral thoraco-lumbar or lumbar spine fusion procedures, among other eligibility criteria. All fusion assessments were completed using the Glassman 5 grade fusion scale. Results: Fifty-five (55) medical records were included in the full analysis set, and of these, 42 were eligible, achieving 97.6% bone fusion with a 95% CI (87.4%, 99.9%). Fusion success rates (Grade 4 or 5): 6 mo 72.7% (n=8/11), 12 mo 97.6% (n=41/42) and 24 mo 100% (n=49/49). No device-related adverse events were reported for Actifuse Shape. A “worst-case” imputation post hoc analysis was performed to take into account five patients who did not show evidence of fusion at 6 mo and were lost to follow up and were assumed to continue showing no evidence of fusion throughout the remaining study period. Forty-one out of 47 (87.2%) patients (95% CI: 74.3, 95.2) achieved successful fusion at 12 mo (±60 days) and 49/55 (89.1%) patients (95% CI: 77.8, 95.9) achieved successful fusion at 24 mo (+60 days). Conclusions: Actifuse Shape is safe and is associated with high rate of bony fusion when implanted as the primary bone graft substitute in spinal fusion surgeries.

Spine Surgery in a Geriatric Population. Is it Really Different?

Spinal degenerative disorders are a major cause of morbidity in the elderly resulting in high dependency. Most of them have a trend to be managed conservatively considering age, comorbidities, and apprehensions of surgical complications. Surgical intervention at early stage with appropriate indications can have better outcomes rather than conservative management in fit patients. The objective of the study is to evaluate the functional outcome in geriatric patients > 60 years who have undergone various spinal procedures for degenerative spine. The study is retrospective, which includes all cases of spinal degenerative disease operated between 2014 and 2016. They were divided into geriatric (>60 years) and non-geriatric cohorts. These include all patients undergoing spinal decompression and/or instrumentation for degenerative disorders of the spine. Patients were interviewed for their functional outcomes in the follow-up period. A total of 184 spine cases were operated upon by a single surgeon, out of which a total of 139 cases were operated for the spinal degenerative condition. Forty-eight patients underwent lumbar spinal fusion procedures, 67 underwent non-instrumented lumbar decompression, and 24 patients underwent cervical procedures. These were further divided into 65 geriatric cases and 74 non-geriatric cases. The outcome was assessed with improvement and functional outcomes for spinal disability. Statistical analysis was performed using SPSS 20. It is concluded that surgical intervention for spinal problems in geriatric patients is not different from the general population. The outcome is also satisfactory provided, the choice of surgical procedure as per its indication is appropriate. The usual preoperative evaluation for the geriatric age group is very important. The performance status before surgery and the comorbidities have a direct bearing on the outcome in these patients.

Pulsed Electromagnetic Field Stimulation in Lumbar Spine Fusion for Patients With Risk Factors for Pseudarthrosis.

Lumbar spinal fusion surgeries are increasing steadily due to an aging and ever-growing population. Patients undergoing lumbar spinal fusion surgery may present with risk factors that contribute to complications, pseudarthrosis, prolonged pain, and reduced quality of life. Pulsed electromagnetic field (PEMF) stimulation represents an adjunct noninvasive treatment intervention that has been shown to improve successful fusion and patient outcomes following spinal surgery. A prospective, multicenter study investigated PEMF as an adjunct therapy to lumbar spinal fusion procedures in patients at risk for pseudarthrosis. Patients with at least 1 of the following risk factors were enrolled: prior failed fusion, multilevel fusion, nicotine use, osteoporosis, or diabetes. Fusion status was determined by radiographic imaging, and patient-reported outcomes were also evaluated. A total of 142 patients were included in the analysis. Fusion status was assessed at 12 months follow-up where 88.0% (n = 125/142) of patients demonstrated successful fusion. Fusion success for patients with 1, 2+, or 3+ risk factors was 88.5%, 87.5%, and 82.3%, respectively. Significant improvements in patient-reported outcomes using the Short Form 36, EuroQol 5 Dimension (EQ-5D) survey, Oswestry Disability Index, and visual analog scale for back and leg pain were also observed compared with baseline scores (P < 0.001). A favorable safety profile was observed. PEMF treatment showed a positive benefit-risk profile throughout the 6-month required use period. The addition of PEMF as an adjunct treatment in patients undergoing lumbar spinal surgery provided a high rate of successful fusion with significant improvements in pain, function, and quality of life, despite having risk factors for pseudarthrosis. PEMF represents a useful tool for adjunct treatment in patients who have undergone lumbar spinal surgery. Treatment with PEMF may result in improved fusion and patient-reported outcomes, regardless of risk factors. NCT03176303.

Developing Mixed-Effects Models to Compare the Predictive Ability of Various Comorbidity Indices in a Contemporary Cohort of Patients Undergoing Lumbar Fusion.

As incidence of operative spinal pathology continues to grow, so do the rates of lumbar spinal fusion procedures. Comorbidity indices can be used preoperatively to predict potential complications. However, there is a paucity of research defining the optimal comorbidity indices in patients undergoing spinal fusion surgery. We aimed to use modeling strategies to evaluate the predictive validity of various comorbidity indices and combinations thereof. Patients who underwent spinal fusion were queried using data from the Nationwide Readmissions Database for the years 2016 through 2019. Using comorbidity indices as predictor variables, receiver operating characteristic curves were developed for pertinent complications such as mortality, nonroutine discharge, top-quartile cost, top-quartile length of stay, and 30-day readmission. A total of 750 183 patients were included. Nonroutine discharges occurred in 161 077 (21.5%) patients. The adjusted all-payer cost for the procedure was $37 616.97 ± $27 408.86 (top quartile: $45 409.20), and the length of stay was 4.1 ± 4.4 days (top quartile: 8.1 days). By comparing receiver operating characteristics of various models, it was found that models using Frailty + Elixhauser Comorbidity Index (ECI) as the primary predictor performed better than other models with statistically significant P -values on post hoc testing. However, for prediction of mortality, the model using Frailty + ECI was not better than the model using ECI alone ( P = .23), and for prediction of all-payer cost, the ECI model outperformed the models using frailty alone ( P < .0001) and the model using Frailty + ECI ( P < .0001). This investigation is the first to use big data and modeling strategies to delineate the relative predictive utility of the ECI and Johns Hopkins Adjusted Clinical Groups comorbidity indices for the prognostication of patients undergoing lumbar fusion surgery. With the knowledge gained from our models, spine surgeons, payers, and hospitals may be able to identify vulnerable patients more effectively within their practice who may require a higher degree of resource utilization.

Erector Spinae Plane Blocks for Circumferential Lumbar Spinal Fusion: Retrospective Cohort Study.

Circumferential lumbar spine fusions are extensive procedures that involve accessing the lumbar spine from multiple approaches. These surgeries often make postoperative pain control challenging, and efforts have been made to find alternative methods of analgesia that do not rely solely on opioids. The use of erector spinae plane (ESP) blocks has been found to be effective in controlling pain while decreasing narcotic requirements in patients undergoing thoracolumbar spine surgery. The purpose of this study is to evaluate the efficacy of ESP blocks for postoperative pain control and its effect on opioid consumption in patients undergoing circumferential lumbar spinal fusion. A retrospective review was performed on patients undergoing 1- or 2-level elective anterior lumbar interbody fusion with open posterior decompression and posterolateral fusion. An analysis was performed to determine the effect of ESP blocks on hospital length of stay (LOS), pain scores using the visual analog scale, and opioid consumption using morphine milligram equivalents. 144 patients were included in the cohort analysis, of whom 36 patients received a preoperative ESP block and 108 did not. Demographic data, comorbidities, and number of levels fused were equally distributed between groups. Patients who received an ESP block had shorter LOS (3.0 vs 4.0 days, P = 0.005) and lower cumulative morphine milligram equivalent in the first 48 hours after surgery (123.7 vs 141.2, P = 0.05). Visual analog scale scores did not significantly differ between patients group except for on postoperative day 4 and at 12-month follow-up. The use of ESP blocks for patients undergoing 1- or 2-level circumferential fusion via an anterior lumbar interbody fusion with concomitant posterior open procedures was associated with decreased postoperative inpatient opioid requirements and LOS. This cohort study supports the growing body of evidence that ESP blocks are a useful adjunct for multimodal pain control. 3 CLINICAL RELEVANCE: The data and results of this study provide clinical evidence supporting the use of ESP blocks in patients undergoing circumferential lumbar spine fusion procedures.

A temporal analysis of perioperative complications following COVID-19 infection in patients undergoing lumbar spinal fusion: When is it safe to proceed?

Background ContextCOVID-19 has been shown to adversely affect multiple organ systems, yet little is known about its effect on perioperative complications after spine surgery or the optimal timing of surgery after an infection. We used the NIH National COVID Cohort Collaborative (N3C) database to characterize the risk profile in patients undergoing spine surgery during multiple time windows following COVID-19 infection. MethodsWe queried the National COVID Cohort Collaborative, a database of 17.4 million persons with 6.9 million COVID-19 cases, for patients undergoing lumbar spinal fusion surgery. Patients were stratified into those with an initial documented COVID-19 infection within 3 time periods: 0 to 2 weeks, 2 to 6 weeks, or 6 to 12 weeks before surgery. ResultsA total of 60,541 patients who underwent lumbar spinal fusion procedures were included. Patients who underwent surgery within 2 weeks of their COVID-19 diagnosis had a significantly increased risk for venous thromboembolic events (OR 2.29, 95% CI 1.58–3.32), sepsis (OR 1.56, 95% CI 1.03–2.36), 30-day mortality (OR 5.55, 95% CI 3.53–8.71), and 1-year mortality (OR 2.70, 95% CI 1.91–3.82) compared with patients who were COVID negative during the same period. There was no significant difference in the rates of acute kidney injury or surgical site infection. Patients undergoing surgery between 2 and 6 weeks or between 6 and 12 weeks from the date of COVID-19 infection did not show significantly elevated rates of any complication analyzed. ConclusionsPatients undergoing lumbar spinal fusion within 2 weeks from initial COVID-19 diagnosis are at increased risk for perioperative venous thromboembolic events and sepsis. This effect does not persist beyond 2 weeks, however, so it may be warranted to postpone non-urgent spine surgeries for at least 2 weeks following a COVID-19 infection or to consider a more aggressive VTE chemoprophylaxis regimen for urgent surgery in COVID-19 patients.

Post-lumbar surgery prescription variation and opioid-related outcomes in a large US healthcare system: an observational study

BACKGROUND CONTEXTSpinal decompression and fusion procedures are one of the most common procedures performed in the United States (US) and remain associated with high postsurgical opioid burden. Despite guidelines emphasizing nonopioid pharmacotherapy strategies for postsurgical pain management, prescribing practices are likely variable and guideline-incongruent. PURPOSEThe purpose of this study was to characterize patient-, care-, and system-level factors associated with opioid, nonopioid pain medication, and benzodiazepine prescribing variation in the US Military Health System (MHS). STUDY DESIGN/SETTINGRetrospective study analyzing medical records from the US MHS Data Repository. PATIENT SAMPLEAdult patients (N=6,625) undergoing lumbar decompression and spinal fusion procedures from 2016 to 2021 in the MHS enrolled in TRICARE at least a year prior to their procedure and had at least one encounter beyond the 90-day postprocedure period, without recent trauma, malignancy, cauda equina syndrome, and co-occurring procedures. OUTCOME MEASURESPatient-, care-, and system-level factors influencing outcomes of discharge morphine equivalent dose (MED), 30-day opioid refill, and persistent opioid use (POU). POU was defined as dispensing of opioid prescriptions monthly for the first 3 months after surgery and then at least once between 90 and 180 days after surgery. METHODS(Generalized) linear mixed models evaluated multilevel factors associated with discharge MED, opioid refill, and POU. RESULTSThe median discharge MED was 375 mg (IQR 225, 580) and days’ supply was 7 days (IQR 4, 10); 36% received an opioid refill and 5%, overall, met criteria for POU. Discharge MED was associated with fusion procedures (+151–198 mg), multilevel procedures (+26 mg), policy release (-184 mg), opioid naïvty (-31 mg), race (Black -21 mg, another race and ethnicity -47 mg), benzodiazepine receipt (+100 mg), opioid-only medications (+86 mg), gabapentinoid receipt (-20 mg), and nonopioid pain medications receipt (-60 mg). Longer symptom duration, fusion procedures, beneficiary category, mental healthcare, nicotine dependence, benzodiazepine receipt, and opioid naivety were associated with both opioid refill and POU. Multilevel procedures, elevated comorbidity score, policy period, antidepressant receipt, and gabapentinoid receipt, and presurgical physical therapy were also associated with opioid refill. POU increased with increasing discharge MED. CONCLUSIONSSignificant variation in discharge prescribing practices require systems-level, evidence-based intervention.

Twelve-Month Results from a Prospective Clinical Study Evaluating the Efficacy and Safety of Cellular Bone Allograft in Subjects Undergoing Lumbar Spinal Fusion.

While autologous bone grafts remain the gold standard for spinal fusion procedures, harvesting autologous bone is associated with significant complications, including donor site infection, hematomas, increased operative time, and prolonged pain. Cellular bone allograft (CBA) presents an alternative to autologous bone harvesting, with a favorable efficacy and safety profile. The current study further investigates CBA as an adjunct to lumbar spinal fusion procedures. A prospective, multicenter, open-label clinical study was conducted in subjects undergoing lumbar spinal fusion with CBA (NCT02969616). Radiographic fusion status was assessed by an independent review of dynamic radiographs and CT scans. Clinical outcome measures included the Oswestry Disability Index (ODI) and visual analogue scale (VAS) for back and leg pain. Adverse-event reporting was conducted throughout 12 months of follow-up. Available subject data at 12 months were analyzed. A total of 274 subjects were enrolled into the study, with available data from 201 subjects (73.3%) who completed 12 months of postoperative radiographic and clinical evaluation at the time of analysis. Subjects had a mean age of 60.2 ± 11.5 years. A higher number of women (n = 124, 61.7%) than men (n = 77, 38.3%) were enrolled, with a collective mean BMI of 30.6 + 6.5 kg/m² (range 18.0-51.4). At month 12, successful fusion was achieved in 90.5% of subjects. A significant (<i>p</i> &amp;lt; 0.001) improvement in ODI, VAS-back, and VAS-leg clinical outcomes was also observed compared to baseline scores. One adverse event related to CBA (postoperative radiculopathy) was reported, with surgical exploration demonstrating interbody extrusion of graft material. This subject reported successful fusion at month 12. CBA represents a viable substitute for harvesting of autograft alone with a high rate of successful fusion and significant improvements in subject-reported outcomes, such as pain and disability. Positive benefit was observed in subjects reporting single and multiple risk factors for pseudoarthrosis.

Risk factors for delirium in elderly patients after lumbar spinal fusion

ObjectiveTo identify perioperative risk factors for postoperative delirium (POD) in patients aged 65 or older undergoing lumbar spinal fusion procedures. Patients and MethodsA retrospective cohort analysis was performed on patients undergoing lumbar spinal fusion over an approximately three-year period at a single institution. Demographic and perioperative data were obtained from electronic medical records. The primary outcome was the presence of postoperative delirium assayed by the Delirium Observation Screening Scale (DOSS) and Confusion Assessment Method for the ICU (CAM-ICU). Univariate and multivariate analyses were performed on the data. ResultsOf the 702 patients included in the study, 173 (24.6%) developed POD. Our analysis revealed that older age (p < 0.001), lower preoperative hemoglobin (p < 0.001), and higher ASA status (p < 0.001), were significant preoperative risk factors for developing POD. The only significant intraoperative risk factor was a higher number of spinal levels that were instrumented (p < 0.001). Higher pain scores on postoperative day 1 (p < 0.001), and lower postoperative hemoglobin (p < 0.001) were associated with increased POD; as were ICU admission (p < 0.001) and increased length of ICU stay (p < 0.001). Patients who developed POD had a longer hospital stay (p < 0.001) with lower rates of discharge to home as opposed to an inpatient facility (p < 0.001). ConclusionRisk factors for POD in older adults undergoing lumbar spinal fusion surgery include advanced age, diabetes, lower preoperative and postoperative hemoglobin, higher ASA grade, greater extent of surgery, and higher postoperative pain scores. Patients with delirium had a higher incidence of postoperative ICU admission, increased length of stay, decreased likelihood of discharge to home and increased mortality, all consistent with prior studies. Further studies may determine whether adequate management of anemia and pain lead to a reduction in the incidence of postoperative delirium in these patients.

Comparison of Spinal Alignment between XLIF, TLIF, PLIF, and PLF in the Treatment of Single Level Spondylolisthesis: A Retrospective Study

Background: Most lumbar spinal fusion procedures are performed to increase fusion potential, correct a deformity, and decompress spinal nerve roots. Nowadays, there are several spinal fusion techniques such as extreme lateral lumbar interbody fusion (XLIF), transforaminal lumbar interbody fusion (TLIF), posterior lumbar interbody fusion (PLIF), and posterolateral fusion (PLF). However, there are no studies directly comparing their capacity to alter lumbar lordosis, segmental lordosis, intervertebral disc height, foraminal height, and the grade of slip for treating single level spondylolisthesis in Thailand. Objective: To compare which lumbar interbody technique amongst XLIF, TLIF, PLIF, and PLF, is the most effective in restoring spinal alignment in cases such as lumbar lordosis, increased segmental lordosis, increased intervertebral disc height, increased foraminal height, and a reduced slip grade in spondylolisthesis patients. Materials and Methods: The medical records and radiographs of single level spondylolisthesis patients treated in Siriraj hospital between 2002 and 2017 were retrospectively reviewed. Clinical data and radiographic parameters such as lumbar lordosis, segmental lordosis, intervertebral disc height, foraminal height, and grade of slip, including preoperative and postoperative data were collected and analyzed. An inter-observer/ intra-observer reliability test for all parameters was also performed. Results: Two hundred forty patients including 192 females and 48 males with a mean age of 60.1 years were included in the present study. There was no statistically significant difference in demographic data except in younger patients in the PLF group and those with shorter length of stays in the XLIF group. The present study results indicated that there was a statistically significant increase in lumbar lordosis, increased foraminal height, and decreased slip grade in the XLIF group when compared to other three groups as TLIF, PLIF, and PLF. Conclusion: All spinal fusion techniques could improve lumbar spinal alignment, however, XLIF is superior to other procedures, especially in lumbar lordosis, foraminal height restoration, and slip grade. Keywords: Lumbar spondylolisthesis; Extreme lateral lumbar interbody fusion; Transforaminal lumbar interbody fusion; Posterior lumbar interbody fusion; Posterolateral fusion; Lumbar lordosis

Design considerations for piezoelectrically powered electrical stimulation: The balance between power generation and fatigue resistance

Quality and timing of bone healing from orthopedic surgeries, especially lumbar spinal fusion procedures, is problematic for many patients. To address this issue, clinicians often use electrical stimulation to improve surgery success rates and decrease healing time in patients with increased risk of pseudarthrosis, including smokers and diabetics. Current invasive electrical stimulation devices require an implantable battery and a second surgery for removal. Piezoelectric composites within an interbody implant generate sufficient power under physiologic loads to deliver pulsed electrical stimulation without a battery and have demonstrated promising preclinical bone growth and fusion success. The objective of the current study was to assess the power generation and fatigue resistance of three commercially manufactured piezocomposite configurations in a modified implant design to demonstrate efficacy as a robust biomaterial within osteogenic implants. The three configurations were electromechanically assessed under physiological lumbar loading conditions, and all configurations produced sufficient power to promote bone healing. Additionally, electrical and mechanical fatigue performance was assessed under high load, low cycle conditions. All configurations demonstrated runout with no gross mechanical failure and two configurations demonstrated electrical fatigue resistance. Future piezoelectric implant design decisions should be based on power generation needs to stimulate bone growth, as mechanical fatigue efficacy was proven for all piezocomposite configurations tested.

P146. MIS TLIF procedures had lower postoperative opioid consumption compared to single position and traditional percutaneous lumbar spinal fusion approaches

<h3>BACKGROUND CONTEXT</h3> One of the reported advantages of MIS spine surgery is less postoperative pain and less postoperative opioid consumption. Traditional lumbar approaches (open TLIF, percutaneous ALIF with flip, and percutaneous LLIF with flip) were compared to minimally invasive (MIS TLIF) and single position (lateral decubitus) anterior posterior surgery (SPS ALIF, SPS LLIF) to evaluate for differences in postoperative opioid consumption. <h3>PURPOSE</h3> To evaluate inpatient MME administration for different lumbar spinal fusion surgeries. <h3>STUDY DESIGN/SETTING</h3> Single-center retrospective cohort study. <h3>PATIENT SAMPLE</h3> A total of 447 single level lumbar spinal fusion procedures from 2013 to 2020: 125 open TLIF, 110 MIS TLIF, 122 Traditional Percutaneous (TP) ALIF/LLIF, and 45 SPS ALIF/LLIF. <h3>OUTCOME MEASURES</h3> Patient demographics, surgical procedure and approach, perioperative clinical characteristics, incidence of ileus and inpatient MME. <h3>METHODS</h3> Patients ≥ 18 years of age who underwent one level TLIF or one level ALIF or LLIF with percutaneous posterior instrumentation between L2-S1. All groups included patients with a diagnosis of Grade I spondylolisthesis, stenosis, degenerative disc disease or pars defect. Statistical analysis included independent samples t-tests and chi-square analyses. Propensity score matching (PSM) was used when comparing SPS ALIF/LLIF vs TP ALIF/LLIF to control for age. MME was calculated as per the Centers for Medicare & Medicaid Services. To adjust for differences in length of stay (LOS), inpatient MME was quantified as a rate per hour. Significance set at p<0.05. <h3>RESULTS</h3> There were no differences in demographics except the MIS TLIF group was older (55.9±12.5 vs 51.6±13.1, p=0.011) than TP ALIF/LLIF. After a PSM for age, SPS ALIF/LLIF had shorter op times (202.3±71.0 vs 271.8±77.7 min, p=0.000) and showed no differences in total MME (322.4 ± 397.8 vs 342.5 ± 243.7, p=0.463) or rates of ileus (both 0%) compared to TP ALIF/LLIF. MIS TLIF had a shorter LOS compared to open TLIF (2.6±1.4 vs 3±1.7 days, p=0.000), lower total MME administration (214.1±235.4 vs 310.3±373.4, p=0.021) but no difference in total MME per hour (3.2±2.4 vs 3.7±2.8, p=0.198). MIS TLIF had shorter op time (212.1±66.4 vs 271.8 ±77.7 min, p=0.000), LOS (2.6±1.4 vs 3.5±1.6 days, p=0.000) and total MME (214.1±235.3 vs 342.5±243.7, p=0.000) than TP ALIF/LLIF. MIS TLIF also had shorter LOS (2.6±1.4 vs 3.3±2.1days, p=0.017), lower total MME (214.1±235.4 vs 322.4±397.8, p=0.037) and similar rates of ileus (0.9% vs 0.0%, p=0.521) compared to SPS ALIF/LLIF. <h3>CONCLUSIONS</h3> Patients undergoing MIS TLIF had lower inpatient opioid intake compared to open TLIF, single level TP ALIF/LLIF, and single level SPS. When propensity score matching for age, there was no difference in opioid administration post operatively in patients undergoing TP ALIF/LLIF or SPS ALIF/LLIF. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

The risks and benefits of early venous thromboembolism prophylaxis after elective spinal surgery: A single-centre experience.

There is a wide ranging incidence of venous thromboembolism after surgery and it continues to be a major cause of morbidity after spinal procedures.This study's aim was to investigate the relationship between timing and administration of venous thromboembolism (VTE) pharmacologic chemoprophylaxis after spinal surgery and the resulting VTE and bleeding complications by reviewing current practices and outcomes at a high-volume single institution to better define opportunities for perioperative intervention to prevent VTE without increasing bleeding complications. All patients who underwent elective one or two-stage lumbar spinal fusion procedures were identified. A logistic regression was used to evaluate (1) risk of symptomatic VTE within 30 days of surgery and (2) bleeding-related complications. The odds of developing a VTE as well as bleeding-related complications were compared among the three treatment groups: no chemoprophylaxis, chemoprophylaxis < 24h of surgery and chemoprophylaxis given > 24h post-surgery. When adjusted for doses administered, the odds of developing a postoperative VTE within 30 days were 0.189 (95% confidence interval (0.044, 0.808)) in patients who received anticoagulation < 24h postoperatively, compared to those who received no anticoagulation (p = 0.025). There was no difference in bleeding rates. Patients undergoing elective spinal surgery who received anticoagulation within 24h of the conclusion of their procedure had an 81% reduction in the odds of developing a deep vein thrombosis within 30 days with no significant difference in bleeding complications.

CORR Insights®: Is Uncontrolled Diabetes Mellitus Associated with Incidence of Complications After Posterior Instrumented Lumbar Fusion? A National Claims Database Analysis.

CORR Insights®: Is Uncontrolled Diabetes Mellitus Associated with Incidence of Complications After Posterior Instrumented Lumbar Fusion? A National Claims Database Analysis.

Clinical efficacy of ultrasound guided bilateral erector spinae block for single-level lumbar fusion surgery: a prospective, randomized, case-control study

BACKGROUND CONTEXTPostoperative experience plays a vital role in patient recovery and does not depend on the type and quality of the surgical procedure alone. Non-opioid therapies have become part of the multimodal analgesic regimen for better pain control and reduced opioid-related side effects. Most recently evolved among these are the regional anesthetic techniques, such as the thoracolumbar interfascial plane (TLIP) block and the erector spinae (ESP) block. PURPOSETo assess the efficacy of ultrasound-guided (US) ESP block for postoperative analgesia after a single level lumbar spine fusion surgery compared with conventional (opioid-based) multimodal postoperative analgesia. STUDY DESIGNA prospective, randomized, controlled, and double-blinded clinical trial. PATIENT SAMPLEA 100 consecutive patients requiring single-level lumbar spinal fusion procedure were randomized into two groups- block (multimodal analgesia with US-ESP) and control (only multimodal analgesia) groups. OUTCOME MEASURESDemographic and surgical data, intra-operative blood loss, duration of surgery, total opioid consumption (TOC) and amount of muscle relaxants used were assessed. Postoperatively, the Numeric pain Rating Scale(NRS), Modified Observer's assessment of Alertness and/or Sedation Scale (MOASS) and Patient satisfaction scores were recorded every 2 hours for the first 6 hours followed by every 6 hours for 24 hours. Continuous variables were analyzed using Student's t-test, and categorical variables were analyzed using either the Chi-square test or Fisher's exact test. p-value < .05 was considered statistically significant. METHODSPatients in both groups underwent the identical protocol for pre-emptive analgesia and induction of anesthesia. Patients in the block group received the US-ESP block after induction and positioning, followed by the multimodal analgesia, while the control group received only the multimodal analgesia. RESULTSBoth groups had identical demographic backgrounds and surgical profile. TOC for 24 hours following induction was significantly lower in the block group than the control group (105.0 ± 15.15 vs 158.00 ± 23.38mcg; p < .001). The total muscle relaxant consumption during surgery was also significantly less in the block group than the control group (51.90 ± 3.17 vs 57.70 ± 5.90; p < .001). The intra-operative blood loss was significantly less (p < .001) in the block group (303.00 ± 86.55 ml) than the control group (437.00 ± 116.85 ml). Compared to the block group, the control group's pain score (NRS) was significantly higher in the first 48 hours following surgery. The MOASS score was significantly lower in the control group (4.46 ± 0.50 vs 3.82 ± 0.82; p < .001) in the immediate postoperative period. The satisfaction score was significantly higher in the block group than the control group (9.52 ± 0.65 vs 8.22 ± 0.79; p < .001). CONCLUSIONThe employed US-ESP block for single-level lumbar fusion surgery is an effective component of multimodal analgesia for reducing blood loss, total opioid consumption, and related side effects with a significant reduction of postoperative pain and higher patient satisfaction.

Incidence and Risk Factors for Postoperative Urinary Retention Following Lumbar Spine Fusion.

This was a prospective cohort study (observational-retrospective chart review). The objective of this study was to determine clinical rates and correlations of postoperative urinary retention (POUR) in elective spine decompression and fusion procedures. POUR is a common postoperative complication that often has a major adverse impact on a patient's recovery from elective lumbar spine surgery. The etiology of POUR in most cases is unknown. Patients undergoing lumbar spine surgery are considered to be at increased risk for POUR due to prone positioning during surgery and intraoperative cauda equina nerve root manipulation. Current studies reporting on POUR after elective spine surgery provide limited insight regarding risk factors and effective prevention strategies for this at-risk population. The purpose of this study is to identify risk factors for POUR after elective lumbar spine surgery and strategies for reducing its incidence. Two hundred consecutive patients aged 50 years or older undergoing combined lumbar decompression and fusion procedures over a 5-month period at a single institution were prospectively observed. Demographic and clinical data were prospectively recorded, including: medical history, surgical data, medications administered, complications, and postoperative hospital course. Factors correlating with POUR through a univariate analysis with P≤0.20 were considered for multivariate analysis. POUR occurred in 19 of 200 patients. Those with POUR were more likely to be male (20% vs. 4%, odds ratio=6.2). Administration of scopolamine (P=0.02), neostigmine (P=0.01), and the total number of levels operated on (P=0.02) were found to be independent risk factors for the development of POUR. Length of surgery, surgical level, the performance of an interbody fusion did not have a bearing on the development of POUR (P>0.05). We describe a single institution's experience of POUR incidence in 200 consecutive patients aged 50 years or older undergoing single or multilevel lumbar spine fusion procedures by 1 of 4 surgeons. Specific demographic and clinical risk factors were identified and a codified classification for POUR in a surgical population is presented.The results of this study will help clinicians appropriately counsel patients undergoing elective lumbar fusion about the potential development of POUR. The perioperative administration of scopolamine and neostigmine should be cautiously considered in men over 50 years of age due to the increased POUR risk. Perioperative scopolamine and neostigmine administration in men over 50 should be avoided when possible to minimize the risk of POUR. Level III.

Impact of body mass index on opioid consumption in lumbar spine fusion surgery

Backgroundin the United States from 1999 to 2000 through 2017–2018, the prevalence of obesity increased from 30.5 to 42.4%, while the prevalence of severe obesity nearly doubled. In lumbar spine surgery, obesity is associated with increased complications, worse perioperative outcomes, and higher costs. The purpose of this study was to examine the association between body mass index (BMI) and opioid consumption in patients undergoing lumbar spine fusion surgery. We hypothesized that obese patients would require more opioids postoperatively. Methodsretrospective review of 306 patients who underwent one- or two-level posterior lumbar interbody fusion surgery between 2016 and 2020. Patients were stratified by BMI as follows: normal weight (18.5–24.9 kg/m2), overweight (25.0–29.9 kg/m2), obese I (30.0–34.9 kg/m2), and obese II–III (≥ 35.0 kg/m2). Patient demographics and preoperative characteristics were compared across BMI cohorts using one-way ANOVA and chi-square analysis. Patients with prior history of opioid use were excluded. Primary outcome measure was postoperative opioid consumption. Secondary outcomes included operative time, length of stay (LOS), discharge destination, and 30-day re-encounter rates. Outcomes were analyzed using multivariable linear regression adjusted for potential confounders. Resultsof 306 total patients, 17.3% were normal weight, 39.9% were overweight, 25.5% were obese I, and 17.3% were obese II–III. Obesity was associated with longer operative times and length of stay (p < 0.001, p = 0.024). For opioid naïve patients, there was no difference in-house opioid consumption when adjusted for kilograms of body mass and LOS (p = 0.083). Classes II–III patients were prescribed more than twice the number of postoperative opioids (p < 0.001) and were on opioids for a longer time postoperatively (p = 0.019). Conclusionobesity is associated with longer operative times, longer LOS, and increased consumption of postoperative opioids. This should be considered when counseling patients preoperatively prior to lumbar spine fusion procedures.

Roadmap for Motor Evoked Potential (MEP) Monitoring for Patients Undergoing Lumbar and Lumbosacral Spinal Fusion Procedures

ABSTRACT MEPs are recommended for patients undergoing lumbar and lumbosacral procedures in which intraoperative neuromonitoring (IONM) is being utilized. While electromyography (EMG) provides critical nerve root proximity information, spontaneous EMG discharges are relatively poor at reliably diagnosing spinal nerve root dysfunction. In contrast, research indicates that MEPs are both sensitive and specific in diagnosing evolving spinal nerve root dysfunction. There is conflicting evidence, however, and it must be emphasized that the value of adding MEPs is only realized when practices and techniques are optimized. The ideal anesthetic plan is an optimized total intravenous anesthetic (TIVA) regimen. Selection of appropriate anesthetics and dosing is important for optimizing baseline response amplitudes and promoting diagnostic confidence in analyzing signal changes. An adaptive set of alert criteria that account for baseline amplitude and morphology fluctuations should guide the determination of significant signal change. The therapeutic impact of accurate diagnostic information depends on the timeliness of diagnosis and intervention. Prior to the start of surgery, a plan to obtain MEPs at least once every 10 minutes during the active part of the procedure and after every significant surgical maneuver should be agreed upon, and the intervention plan should include but not be limited to possible removal of hardware and release of retraction or distractive forces. In summary, MEPs can improve monitoring of at-risk nerve root function, but the accuracy and therapeutic impact of such monitoring depend on perioperative planning and communication that optimize use of this modality.

33. Utilizing predictive analytics to understand the influence of modifiable risk factors on readmission in patients receiving lumbar spinal fusion

BACKGROUND CONTEXT Within the last several decades, the field of preventive medicine has grown immensely and is now considered the first line of defense against disease and disability. Although many factors lie beyond the scope of patient control, a small number of modifiable risk factors remain within reach. Yet, research outlining the influence of modifiable risk factors on the perioperative well-being of lumbar spinal fusion patients continues to be limited. PURPOSE Here, we develop predictive models to analyze the influence of modifiable risk factors on postfusion outcomes and complications using data from a national database. STUDY DESIGN/SETTING Retrospective cohort analysis using the 2016 National Readmission Database. PATIENT SAMPLE Using the 2016 National Readmission Database, we conducted a retrospective cohort analysis of 110,396 patients who received a lumbar spinal fusion procedure. Modifiable risk factors (MRF) were defined as smoking, alcohol use, malnutrition, and elevated lipid panel. From this cohort, 47,374 (42.9%) patients with at least one MRF were identified using ICD-10 codes. OUTCOME MEASURES Associated costs, perioperative complications, and nonelective readmission at 30, 60, and 90 days. METHODS We used propensity score matching to obtain a group of 47,374 one-to-one age- and sex-matched control patients from the initial 110,396 patient lumbar spinal fusion cohort with no MRFs for comparison. Data were collected for those readmitted within 30, 60, and 90 days, and all patients with routine or elective follow-ups were excluded. Statistics were conducted using RStudio, and predictive algorithms were developed using generalized Gaussian logistic regression models. Significance was determined by Welch Two Sample t-testing, Tukey multiple comparison of means, and Wald testing. RESULTS The percent of female patients in the MRF-present and control groups were 51.6% and 52.2% respectively. The average age of the MRF cohort was found to be 62.36 years, and the average age of the propensity matched control group was 62.15 years at the time of lumbar fusion. Significant differences in readmission between the two groups were found at 30 days (MRF: 5.21%, Control: 4.47%, p CONCLUSIONS The presence of MRFs significantly increased the rate of nonelective readmissions in patients undergoing lumbar spinal fusion. In fact, the number of present MRFs at the time of primary admission significantly increase the hospital LOS, total surgical cost, and future readmission rate at 30, 60, and 90 days. Predictive algorithms are promising new developments that may allow for surgical optimization in patients admitted with multiple MRFs and may find significant patterns that traditional statistical methods may overlook. Preventive approaches aimed at minimizing the presence of MRFs should be considered in patients undergoing lumbar spinal fusion procedures. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

12. Health care costs and characteristics of spinal fusion patients receiving concentrated bone marrow aspirate (BMAC), iliac crest autograft or bone morphogenic protein (BMP) therapy: a retrospective cohort study utilizing administrative claims

BACKGROUND CONTEXT To aid in fusion, surgeons may choose to use a biologic or other grafting agent in posterior lumbar spinal fusion procedures. This study explored the differences in cost and a variety of outcomes of bone marrow aspirate concentrate (BMAC), iliac crest autogenous bone grafting (autograft) and recombinant human bone morphogenetic proteins (rhBMP) -2 and -7. Autograft complications include pain, risk of infection and donor morbidity. BMP drawbacks are high cost and at risk of stimulating too much bone growth. While BMAC has been shown to promote bone and soft tissue healing, possible risks include bleeding and infection or nerve damage. PURPOSE A market assessment was conducted to explore the clinical value of each product. The study also looked at patient demographics, outcomes, and cost across the grafting products. STUDY DESIGN/SETTING Retrospective administrative claims data from the Optum Commercial and Medicare Advantage affiliated claims dataset between January 1, 2016 and December 31, 2017. PATIENT SAMPLE The final study cohort consisted of 14,668 patients (BMAC: n=3,181; autograft: n=11,085; BMP: n=402) in the US. 84.5% (n=12,683) of patients had only 1 index procedure product and 97.2% (n=14,251) had a successful fusion. The majority of patients were aged 65+ (n=7,581 /52%), female (n=8,122 /55%), and received Medicare coverage (n=8,639 /59%). OUTCOME MEASURES Data on select patient demographic and clinical characteristic measures were collected, including Charlson Comorbidity Index (CCI) score and top AHRQ comorbidities. Inpatient and outpatient hospital costs, length of stay (LOS) and mean standardized cost per patient by procedure were among the data collected to drive the cost analysis. METHODS Patients with >= 1 a CPT code for a procedure of interest for autograft or BMAC or an ICD-10-PCS code for BMP of interest were identified during the study time period. Patients were indexed at admission date of MS-DRG involving first observed instance of a procedure of interest and required to have 6 months pre-and 12 months post-index continuous medical and pharmacy coverage. Data were analyzed using descriptive statistics. The mean differences in costs were assessed using Student's t-test for statistical significance. RESULTS The average length of stay (BMAC=3.6 days; autograft=3.8 days; BMP=4.3 days [p-value: BMAC vs autograft= CONCLUSIONS Data from this study showcases the cost savings and potential impact on health outcomes which can be incurred through the implementation of BMAC as a biologic in treating spine fusion patients. Given the rising cost of spinal fusion procedures performed annually in the US, further research should focus on evaluating the cost-effectiveness of the various procedures. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.