Patients Undergoing Lumbar Spinal Fusion Research Articles

The effects of psychological distress after surgery in patients undergoing lumbar spinal fusion

BackgroundThe aim of this study was to evaluate the psychological distress pre-operatively, at 3, 6, and 12 months in patients who underwent lumbar spine fusion surgery.MethodsA total of 440 patients received instrumented lumbar spine fusion were enrolled. Psychological distress was evaluated using the Modified Somatic Perception Questionnaire (MSPQ) and the Modified Zung Depressive Index (ZDI). The results of lumbar fusion surgery were evaluated using the Oswestry Disability Index (ODI), the Japanese Orthopedic Association (JOA-29), and the visual analog scale (VAS).ResultsPsychological distress was reported among 23% of patients and 7, 5.5, and 4.0% of the patients preoperatively, at 3, 6, and 12 months after lumbar surgery, respectively. The mean MSPQ score decreased from 8.78 (before surgery) to 4.30, 3.52, and 3.43 at 3, 6 and 12 months in after surgery, respectively, in patients with psychological distress patients (p < 0.001). The mean ZDI score decreased from 17.78 to 12.48, 10.35, and 9.61 (p < 0.001). The mean ODI score decreased from 22.91 to 11.78, 10.13, and 9.96 (P < 0.001). The mean JOA score increased from 13.65 to 22.30, 23.43, and 23.61 (P < 0.001). The mean low back pain (LBP) VAS score decreased from 4.48 to 1.96, 1.52, and 1.51 (P < 0.001); moreover, the mean leg pain (LP) VAS score decreased from 5.30 to 1.30, 1.04, and 1.03 (P < 0.001).ConclusionsPatients with psychological distress may experience surgical intervention benefits equal to those of ordinary patients. Moreover, reduced pain and disability after surgical intervention may also alleviate psychological distress. Hence, we highly recommend that patients with psychological distress undergo surgical intervention as normal patients do, but appropriate screening measures and interventions are necessary.

Effect of intraoperative dexmedetomidine on recovery of gastrointestinal function after caesarean section undergoing spinal and epidural anesthesia: A randomized, double blind, placebo-controlled clinical trial

ObjectiveGastrointestinal dysfunction after cesarean section negatively affects postoperative recovery. Dexmedetomidine has been shown to improve postoperative gastrointestinal function in patients undergoing lumbar spinal fusion surgery and laparoscopic gastrectomy, but its role in cesarean section has not been fully elucidated. The study aimed to investigate the effect of dexmedetomidine on gastrointestinal function after cesarean section. Study Design220 pregnant women who underwent elective cesarean section were randomized into group D and group S. Group D patients received a loading dose of 0.5 μg/kg of dexmedetomidine for 10 mins followed by a maintenance dose of 0.5 μg/kg/h intravenously immediately after the umbilical cord was cut intraoperatively, whereas the other group (group S) received an equivalent quantity of normal saline as loading and maintenance dose IV by infusion pump. The primary outcome was time to first flatus after surgery (hours). Secondary outcomes included time to first feces and first bowel sounds (hours), incidence rates of postoperative gastrointestinal complications, and the length of postoperative hospital stay (days). ResultsModified intention-to-treat analysis showed that patients in Group D had a significantly shorter time to first flatus (21 [16 to 28.25] vs. 25 [18 to 32.25] h; P = 0.014), time to first feces (45.5 [35.75 to 55.25] vs. 53 [40 to 60] h; P = 0.019), and time to first bowel sounds (P = 0.010), a lower incidence of abdominal distension (21[20.6 %] vs. 36[34.3 %], P = 0.027), shorter length of postoperative hospital stay (P = 0.010) compared to patients in Group S. ConclusionIntraoperative dexmedetomidine infusion reduces the time to first flatus, the incidence of abdominal distension, and shortens the length of hospital stay, promoting gastrointestinal function after cesarean section.

Impact of congestive heart failure on patients undergoing lumbar spine fusion for adult spine deformity.

With the increasing amount of elective spine fusion patients presenting with cardiac disease and congestive heart failure, it is becoming difficult to assess when it is safe to proceed with surgery. Assessing the severity of heart failure (HF) through ejection fraction may provide insight into patients' short- and long-term risks. The purpose of this study was to assess the severity of HF on perioperative outcomes of spine fusion surgery patients. This was a retrospective cohort study of the PearlDiver database. We enrolled 670,526 patients undergoing spine fusion surgery. Thirty-day and 90-day complication rates, discharge destination, length of stay (LOS), physician reimbursement, and hospital costs. Patients undergoing elective spine fusion surgery were isolated and stratified by preoperative HF with preserved ejection fraction (P-EF) or reduced ejection fraction (R-EF) (International Classification of Diseases-9: 428.32 [chronic diastolic HF] and 428.22 [chronic systolic HF]). Means comparison tests (Chi-squared and independent samples t-tests, as appropriate) compared differences in demographics, diagnoses, comorbidities, procedural characteristics, LOS, 30-day and 90-day complication outcomes, and total hospital charges between those diagnosed with P-EF and those not R-EF. Binary logistic regression assessed the odds of complication associated with HF, controlling for levels fused (odds ratio [OR] [95% confidence interval]). Statistical significance was set at P < 0.05. Totally 670,526 elective spine fusion patients were included. Four thousand and seventy-seven were diagnosed with P-EF and 2758 R-EF. Overall, P-EF patients presented with higher rates of morbid obesity, chronic kidney disease, chronic obstructive pulmonary disease, diabetes mellitus, and hypertension (all P < 0.001). In relation to No-HF, P-EF patients had higher rates of 30-day major complications including pulmonary embolism, pneumonia, cerebrovascular accident (CVA), myocardial infarctions (MI), sepsis, and death (all P < 0.001). Furthermore, P-EF was associated significantly with increased odds of pneumonia (OR: 2.07 [1.64-2.56], P < 0.001) and sepsis (OR: 2.09 [1.62-2.66], P < 0.001). Relative to No-HF, R-EF was associated with significantly higher odds of MI (OR: 3.66 [2.34-5.47]), CVA (OR: 2.70 [1.67-4.15]), and pneumonia (OR: 1.85 [1.40-2.40]) (all P < 0.001) postoperative within 30 days. Adjusting for prior history of MI, CAD, and the presence of a pacemaker R-EF was a significant predictor of an MI 30 days postoperatively (OR: 2.2 [1.14-4.32], P = 0.021). Further adjusting for history of CABG or stent placement, R-EF was associated with higher odds of CVA (OR: 2.11 [1.09-4.19], P = 0.028) and MI (OR: 2.27 [1.20-4.43], P = 0.013). When evaluating the severity of HF before spine surgery, R-EF was associated with a higher risk of major complications, especially the occurrence of a myocardial infarction 30 days postoperatively. During preoperative risk assessment, congestive HF should be considered thoroughly when thinking of postoperative outcomes with emphasis on R-EF.

Preoperative and Postoperative Segmental and Overall Range of Motion in Patients Undergoing Lumbar Spinal Fusion Using HA-Infused PEEK and HA-Treated Titanium Alloy Interbody Cages.

Retrospective observational radiographic analysis. Determine how single level lumbar interbody fusion (LIF) alters segmental range of motion (ROM) at adjacent levels and decreases overall ROM. This study included 54 patients who underwent single-level anterior (ALIF, 39%), thoraco-LIF (TLIF, 26%), posterior LIF (PLIF, 22%), or lateral LIF (LLIF, 13%) (L2-3/L3-4/L4-5/L5-S1: 4%/13%/35%/48%). Segmental ROM from L1-2 to L5-S1 and the overall lumbar ROM (L1-S1) were assessed from preoperative and postoperative flexion-extension radiographs. K-means cluster analysis was used to identify ROM subgroups. The overall L1-S1 ROM decreased 14% (25.5 ± 20.4° to 22.0 ± 17.2°, P = .104) postoperatively. ROM at the fusion level decreased 77% (4.8 ± 5.0° to 1.1 ± 1.1°, P < .001). Caudal adjacent segment ROM decreased 12% (5.2 ± 5.7° to 4.6 ± 4.4°, P = .345) and cranially ROM increased 34% (4.3 ± 5.0° to 5.7 ± 5.7°, P = .05). K-cluster analysis identified 3 distinct clusters (P < .05). Cluster 1 lost more ROM and had less improvement in patient-reported outcomes measures (PROMs) than average. Cluster 2 had less ROM loss than average with worse PROMs improvement. Cluster 3 did not have changes in ROM and better improvement in PROMs than average. Successful fusion was verified in 96% of all instrumented segments with >6months follow-up (ROM <4°). Following single-level L IF, patients should expect a loss of 3.3°, or 14% of overall lumbar motion with increases in ROM of the cranial segment. However, specific clusters of patients exist that experience different relative changes in ROM and PROMs.

The Influence of Hospital Type, Insurance Type, and Patient Income on 30-Day Complication and Readmission Rates Following Lumbar Spine Fusion.

Several studies have shown that factors such as insurance type and patient income are associated with different readmission rates following certain orthopaedic procedures. The literature, however, remains sparse with regard to these demographic characteristics and their associations to perioperative lumbar spine fusion outcomes. The purpose of this study was to assess the associations between hospital type, insurance type, and patient median income to both 30-day complication and readmission rates following lumbar spine fusion. Patients who underwent primary lumbar spine fusion (n = 596,568) from 2010-2016 were queried from the National Readmissions Database (NRD). Incidence of 30-day complication and readmission rates. All relevant diagnoses and procedures were identified using International Classification of Disease, 9th and 10th Edition (ICD-9, 10) codes. Hospital types were categorized as metropolitan non-teaching (n = 212,131), metropolitan teaching (n = 364,752), and rural (n = 19,685). Insurance types included: Medicare (n = 213,534), Medicaid (n = 78,520), private insurance (n = 196,648), and out-of-pocket (n = 45,025). Patient income was divided into the following quartiles: Q1 (n = 112,083), Q2 (n = 145,755), Q3 (n = 156,276), and Q4 (n = 147,289), wherein quartile 1 corresponded to lower income ranges and quartile 4 to higher ranges. Statistical analysis was conducted in R. Kruskal-Wallis tests with Dunn's pairwise comparisons were performed to analyze differences in 30-day readmission and complication rates in patients who underwent lumbar spine fusion. Complications analyzed included infection, wound injury, hematoma, neurological injury, thromboembolic event, and hardware failure. 30-day readmission was significantly higher in metropolitan teaching hospitals compared to metropolitan non-teaching hospitals and rural hospitals (P < .05). Patients from metropolitan teaching hospitals had significantly higher rates of infection (P < .001), wound injury (P < .001), hematoma (P = .018), and hardware failure (P < .002) compared to those treated at metropolitan non-teaching hospitals. Privately insured patients were significantly less likely to be readmitted at 30 days than those paying with Medicare or Medicaid (P < .01). Patients with private insurance also experienced significantly lower rates of hematoma formation than Medicare beneficiaries and out-of-pocket payers (P < .01), postoperative wound injury compared to Medicaid patients and out-of-pocket payers (P < .005), and infection compared to all other groups (P < .001). Patients in Quartile 4 experienced significantly greater rates of hematoma formation compared to those in Quartiles 1 and 2 and were more likely to experience a thromboembolic event compared to all other groups. Patients undergoing lumbar spine fusion at metropolitan non-teaching hospitals and paying with private insurance had significantly lower 30-day readmission rates than their counterparts. Complications within 30 days following lumbar spine fusion were significantly higher in patients treated at metropolitan teaching hospitals and in Medicare and Medicaid beneficiaries. Aside from a few exceptions, however, patient income was generally not associated with differential complication rates.

Sex differences in the accuracy of vertebral bone quality score assessing bone density in patients undergoing lumbar spinal fusion.

Low bone mineral density (BMD) significantly increases the risk of complications in patients undergoing spinal fusion. Existing evidence indicates that traditional dual-energy x-ray absorptiometry (DEXA) and quantitative CT (QCT) screening are underutilized in spine surgery. The MRI-based vertebral bone quality (VBQ) score provides a tool for primary screening of bone density. The validity of this score as a predictor across sexes has not been investigated. This study aimed to explore the effect of sex on the diagnostic efficacy of the VBQ in predicting osteopenia/osteoporosis and whether a sex-specific threshold exists. In this retrospective cohort study, patients who underwent lumbar fusion at a tertiary care center were reviewed. VBQ was obtained by noncontrast T1-weighted MRI. Patients were stratified according to sex and bone density. Data were analyzed between the groups. Pearson correlation analysis and linear regression were used to analyze the correlation between the VBQ and DEXA T values. Receiver operating characteristic (ROC) curve analysis, including area under the curve (AUC) calculation, was used to evaluate the predictive performance of VBQ for low BMD in both sexes. A total of 271 patients (92 male, 179 female patients) were analyzed. The correlation coefficient between VBQ and the lowest T value was -0.40 for male and -0.554 for female patients. In comparing the bone density subgroups, among male patients a significant difference in the VBQ scores was observed only between the normal and osteoporosis subgroups (p = 0.012). VBQ demonstrated statistically significant differences among female patients across all three subgroups (p < 0.001). The ROC analysis revealed that the predictive performance of VBQ in detecting low BMD was more consistent with the gold-standard DEXA results in female than in male patients (AUC 0.647 vs AUC 0.823, p = 0.02). The optimal thresholds were similar in both sexes. Compared with male patients, VBQ has better discrimination between female patients with low BMD and those with normal bone density. Although the correlation between VBQ and bone density is weaker in male than in female patients, the optimal thresholds are similar in both sexes.

Twenty-four-month interim results from a prospective, single-arm clinical trial evaluating the performance and safety of cellular bone allograft in patients undergoing lumbar spinal fusion

BackgroundAutologous bone grafts are the gold standard for spinal fusion; however, harvesting autologous bone can result in donor site infection, hematomas, increased operative time, and prolonged pain. Cellular bone allografts (CBAs) are a viable alternative that avoids the need for bone harvesting and may increase fusion success alone or when used as an adjunct material. The present study examined the efficacy and safety of CBA when used as an adjunct graft material to lumbar arthrodesis.MethodsA prospective, single-arm, multicenter clinical trial (NCT 02969616) was conducted in adult subjects (> 18 years of age) undergoing lumbar spinal fusion with CBA graft (CBA used as primary (≥ 50% by volume), with augmentation up to 50%). Radiographic fusion status was assessed by an independent review of dynamic radiographs and CT scans. Clinical outcomes were assessed with the Oswestry Disability Index (ODI), and Visual Analog Scales (VAS) score for back and leg pain. Adverse events were assessed through the 24-month follow-up period. The presented data represents an analysis of available subjects (n = 86) who completed 24 months of postoperative follow-up at the time the data was locked for analysis.ResultsPostoperative 24-month fusion success was achieved in 95.3% of subjects (n = 82/86) undergoing lumbar spinal surgery. Clinical outcomes showed statistically significant improvements in ODI (46.3% improvement), VAS-Back pain (75.5% improvement), and VAS-Leg pain (85.5% improvement) (p < 0.01) scores at Month 24. No subject characteristics or surgical factors were associated with pseudoarthrosis. A favorable safety profile with a limited number of adverse events was observed.ConclusionsThe use of CBA as an adjunct graft material showed high rates of successful lumbar arthrodesis and significant improvements in pain and disability scores. CBA provides an alternative to autograft with comparable fusion success rates and clinical benefits.Trial registrationNCT 02969616.

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.

56. Use of dexamethasone in the immediate postoperative period is associated with increased risk of instrumentation and surgical site complications in diabetic patients undergoing lumbar spinal fusion

56. Use of dexamethasone in the immediate postoperative period is associated with increased risk of instrumentation and surgical site complications in diabetic patients undergoing lumbar spinal fusion

100. Increased risk for venous thromboembolic events in patients undergoing lumbar spinal fusion within two weeks of COVID-19 infection

100. Increased risk for venous thromboembolic events in patients undergoing lumbar spinal fusion within two weeks of COVID-19 infection

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.

Perioperative risk factors related to complications of lumbar spine fusion surgery in elderly patients

PurposeTo analyze the perioperative risk factors related to lumbar spine fusion surgery in elderly patients.Methods202 elderly patients (age range 77–92 years old) who have underwent lumbar spinal fusion surgeries between January 2019 and June 2021 were retrospectively investigated. Information of age, sex, comorbidity, fixation segments, operation time, surgical blood loss and perioperative complications during hospitalization were collected. Risk factors for complications were analyzed. Student’s t-test, chi-square test, Mann-Whitney U‑test and multivariate generalized linear models were used.ResultsIn this study, 31 patients presented complications (15.3%) in these elderly patients with an average age of 79.1 years, including 1 patient with intraoperative complication and 30 patients with postoperative complications; and 2 out of 31 patients (1%) died. The elderly patients were divided into group A (24 patients) with major postoperative complications and group B (178 patients) without major postoperative complications. Major postoperative complications were significantly associated with age (univariate analysis, t = 3.92, P < 0.001; multivariate analysis, OR = 1.323, 95%CI 1.126–1.554, P = 0.001), but not significantly associated with other factors tested (sex, comorbidity, fixation segments, operation time, surgical blood loss). Then 173 patients (range 77–81 years) were selected and the rate of major postoperative complications of each age from 78 to 81 years was compared with that of 77 years patients, respectively. We found that the ratios of complications at 80 years (OR = 10.000, P = 0.019) and 81 years (OR = 10.000, P = 0.009) were higher than the ratio at 77 years.ConclusionsAlthough with great progress of medical technology, increasing age was still the independent risk factor for major postoperative complications in elderly patients undergoing lumbar spinal fusion surgery. As for the incidence of major postoperative complications, 80 and 81 years old patients was 10 folds higher than that of 77 years old patients, reminding us to pay more attention to 80 years old and even older patients.

Effect of oral pregabalin on post operative analgesia in patients undergoing lumbar spine fusion surgeries under general anesthesia

Pregabalin has been used successfully as a component of multimodal analgesia regimen in a variety of surgical procedures. However, side effects such as dizziness and somnolence have been reported especially with doses ≥300mg. We hypothesized that using a lower cumulative dose of oral pregabalin in a divided dosing regimen would lower the incidence of side effects while providing adequate postoperative analgesia in patients undergoing lumbar spine fusion surgery. Seventy adult patients of either sex of ASA 1-3, undergoing lumbar spine fusion surgery under general anesthesia were randomly divided into two equal groups. Group B received oral pregabalin 150mg one hour before induction and 75mg 2 hours after surgery. Group A received oral placebo at the corresponding time points. Pain was assessed using Visual Analogue Score (VAS) at extubation, 2, 4, 6, 12, 18 and 24 hours after surgery. In the first 24 hours after surgery, the mean VAS scores were significantly lower in Group B (P0.001) at all time points while tramadol consumption for rescue analgesia (P0.001) and postoperative nausea (P0.013) and vomiting (P0.011) were significantly higher in Group A. Preoperative anxiety and sedation scores and postoperative incidence of dizziness and somnolence were comparable between the two groups. Low dose oral pregabalin preoperatively and postoperatively using a divided dose regimen can be safely used to provide adequate postoperative analgesia with low incidence of side effects after lumbar spine fusion surgeries.

Predictors of Blood Transfusion in Patients Undergoing Lumbar Spinal Fusion

To determine risk factors for perioperative blood transfusion after lumbar fusion surgery. After institutional review board approval, a retrospective cohort study of adult patients who underwent lumbar fusion at a single, urban tertiary academic center was retrospectively retrieved. Our primary outcome, blood transfusion, was collected via chart query. A receiver operating characteristic curve was used to evaluate the regression model. A P-value < 0.05 was considered statistically significant. Of the 3,842 patients, 282 (7.3%) required a blood transfusion. For patients undergoing posterolateral decompression and fusion, predictors of transfusion included age (P < 0.001) and more levels fused (P < 0.001). A higher preoperative hemoglobin level (P < 0.001) and revision surgery (P= 0.005) were protective of blood transfusion. For patients undergoing transforaminal lumbar interbody fusion, greater Elixhauser comorbidity index (P < 0.001), longer operative time (P= 0.040), and more levels fused (P= 0.030) were independent predictors of the need for blood transfusion. Patients with a higher body mass index (P= 0.012) and preoperative hemoglobin level (P < 0.001) had a reduced likelihood of receiving a transfusion. For circumferential fusion, greater age (P= 0.006) and longer operative times (P= 0.015) were independent predictors of blood transfusion, while a higher preoperative hemoglobin level (P < 0.001) and male sex (P= 0.002) were protective. Our analysis identified older age, lower body mass index, greater Elixhauser comorbidity index, longer operative duration, more levels fused, and lower preoperative hemoglobin levels as independent predictors of requiring a blood transfusion following lumbar spinal fusion. Different surgical approaches were not found to be associated with transfusion.

Implementation of a Private Payer Bundled Payment Model while Maintaining High Value Lumbar Spinal Fusion.

Retrospective single-institution cohort. To evaluate implementation of a commercial bundled payment model in patients undergoing lumbar spinal fusion. BPCI-A caused significant losses for many physician practices, prompting private payers to establish their own bundled payment models. The feasibility of these private bundles has yet to be evaluated in spine fusion. Patients undergoing lumbar fusion from October-December 2018 in BPCI-A prior to our institution's departure were included for BPCI-A analysis. Private bundle data was collected from 2018-2020. Analysis of the transition was conducted among Medicare-aged beneficiaries. Private bundles were grouped by calendar year (Y1, Y2, Y3). Stepwise multivariate linear regression was performed to measure independent predictors of net deficit. Net surplus was lowest in Y1 ($2,395, P=0.03) but did not differ between our final year in BPCI-A and subsequent years in private bundles (all, P>0.05). AIR and SNF patient discharges decreased significantly in all private bundle years compared to BPCI. Readmissions fell from 10.7% (N=37) in BPCI-A to 4.4% (N=6) in Y2 and 4.5% (N=3) Y3 of private bundles (P<0.001). Being in Y2 or Y3 was independently associated with a net surplus in comparison to the Y1 (β: $11,728, P=0.001; β: $11,643, P=0.002). Post-operatively, length of stay in days (β: $-2,982, P<0.001), any readmission (β: -$18,825, P=0.001), and discharge to AIR (β: $-61,256, P<0.001) or SNF (β: $-10,497, P=0.058) were all associated with a net deficit. Non-governmental bundled payment models can be successfully implemented in lumbar spinal fusion patients. Constant price adjustment is necessary so bundled payments remain financially beneficial to both parties and systems overcome early losses. Private insurers who have more competition than the government may be more willing to provide mutually beneficial situations where cost is reduced for payers and health systems.

The effect of erector spinae plane block on the use of anesthetic medications in lumbar spine surgery.

To reduce the drug side effects and facilitate the emergence from anesthesia after complex spine surgery, various methods have been proposed. One of these methods is ESPB, which has been less studied. Hence, we conducted this study to evaluate the effectiveness of ESPB on the use of anesthetic drugs in lumbar spine surgery. In this study, 70 patients undergoing lumbar spine fusion surgery were studied. Patients were randomly divided into two groups: the case group (n=35), in which bilateral ESPB was done, and the control group (n=35). After standard anesthesia protocols, anesthesia was maintained with isoflurane in both groups. Intraoperative isoflurane and perioperative opioid consumption were recorded. Statistical analysis was performed using SPSS software version 21. Intraoperative use of fentanyl in the case group was significantly lower than the control group (14.29±21.5 vs. 65.96±73.33 µg, p<0.001). Furthermore, isoflurane consumption in the intervention group compared to the controls was significantly lower (20.71±5.02 versus 28.83±8.68 mL, p<0.001). Moreover, the emergence time was significantly shorter in the case group than in the control group (8.49±4.30 minutes versus 15.00±4.94, p<0.001). In the post-anesthesia care unit 1 h after surgery, the pain scores in the case group were significantly lower than the controls (p<0.001). ESPB under ultrasound guidance is an effective method of regional anesthesia/analgesia for lumbar spine surgery (fusion) by decreasing the consumption of anesthetics during and following the surgery.

Risk factors for early reoperation in patients after posterior lumbar interbody fusion surgery. A propensity-matched cohort analysis

BackgroundReoperation is usually associated with poor results and increased morbidity and hospital costs. However, the rates, causes, and risk factors for reoperation in patients undergoing lumbar spinal fusion surgery remain controversial. This study aimed to identify the risk factors for early reoperation after posterior lumbar interbody fusion surgery and to compare the clinical outcomes between patients who underwent reoperation and those who did not. MethodsWe investigated a multicenter medical record database of 1263 patients who underwent posterior lumbar interbody fusion surgery between 2012 and 2015. A total of 72 (5.7%) reoperations within two years after surgery were identified and were propensity-matched for age, sex, number of fusion segments, and surgeon's experience. ResultsWe analyzed a total of 114 patients (57 who underwent reoperation (R group) and 57 who did not (C group)). The mean age was 62.6 ± 13.4 years, with 78 men and 36 women. The mean number of fused segments was 1.2 ± 0.5. Surgical site infection was the most common cause of reoperation. There were significant differences in the incidence of diabetes mellitus (p = 0.024), preoperative ambulation status (p = 0.046), and ASA grade (p < 0.001) between the C and R groups. The recovery rate of the Japanese Orthopaedic Association score was significantly lower in the R group compared to the C group (R: 50.5 ± 28.8%, C: 63.9 ± 33.7%, p = 0.024). There were significant differences in the bone fusion rate (R: 63.2%, C: 96.5%, p < 0.001) and incidence of screw loosening (R: 31.6%; C: 10.5%; p = 0.006). ConclusionDiabetes mellitus, preoperative ambulation status, and ASA grade were significant risk factors for early reoperation following posterior lumbar interbody fusion surgery. The patients who underwent early reoperation had worse clinical outcomes than those who did not.

Effects of perioperative use of two doses of magnesium sulfate infusion on intraoperative blood loss in patients undergoing lumbar spinal fusion surgery

Objective: In general, spinal fusion surgery causes heavy bleeding. The purpose of this study was to evaluate the use of two different doses of magnesium sulfate to control the bleeding in lumbar fusion surgery. Methods: This study was carried out as a randomized double-blinded clinical trial in 2020 in Al-Zahra hospital in Isfahan. The participants were 60 patients selected using inclusion and exclusion criteria and were randomly allocated into three groups. In the first group, 50 mg/kg and in the second group, 40 mg/kg magnesium sulfate was infused. The third group received normal saline. From the beginning of anesthesia, heart rate, diastolic and systolic blood pressure, respiratory rate and blood oxygen saturation percentage were monitored and logged every 30 minutes during the operation and recovery. The volume of bleeding during the operation was calculated by counting the number of gauzes used and the amount of suctioned blood during the operation. Other required information such as the duration of operation, duration of anesthesia, time of intubation and the time period of hospitalization and recovery were determined and recorded in all patients. We used independent t-test and repeated measure ANOVA tests to compare data between different time lines and also different groups. P value&lt;0.05 was considered as significance threshold. The collected data were analyzed by using SPSS software version 23. Results: The group receiving 50 mg/kg magnesium sulfate had a significantly lower systolic blood pressure compared to other groups within 15, 30 and 45 minutes after the injections (P=0.04 for all). The pulse rate was significantly lower in the 50 mg/kg magnesium sulfate group compared to other groups within 15, 30 and 45 minutes after the injections (P&lt;0.05 for all). Patients that received 50 mg/kg magnesium sulfate had a lower duration of surgery (P=0.007), lower duration of anesthesia (P=0.007), lower bleeding volume (P&lt;0.001), lower fluid intake (P=0.01) and also lower transfused blood (P=0.01). The surgeons also had a significantly higher satisfaction with these patients (P=0.001). Conclusion: Injection of 50 mg/kg magnesium sulfate had a correlation with reduced blood pressure as well as bleeding volume compared to 40 mg/kg magnesium sulfate.

Correlation between Adrenoceptor Expression and Clinical Parameters in Degenerated Lumbar Intervertebral Discs

Despite advanced knowledge of the cellular and biomechanical processes of intervertebral disc degeneration (IVDD), the trigger and underlying mechanisms remain unclear. Since the sympathetic nervous system (SNS) has been shown to exhibit catabolic effects in osteoarthritis pathogenesis, it is attractive to speculate that it also influences IVDD. Therefore, we explored the adrenoceptor (AR) expression profile in human IVDs and correlated it with clinical parameters of patients. IVD samples were collected from n = 43 patients undergoing lumbar spinal fusion surgery. AR gene expression was analyzed by semi-quantitative polymerase chain reaction. Clinical parameters as well as radiological Pfirrmann and Modic classification were collected and correlated with AR expression levels. In total human IVD homogenates α1A-, α1B-, α2A-, α2B-, α2C-, β1- and β2-AR genes were expressed. Expression of α1A- (r = 0.439), α2A- (r = 0.346) and β2-AR (r = 0.409) showed a positive and significant correlation with Pfirrmann grade. α1A-AR expression was significantly decreased in IVD tissue of patients with adjacent segment disease (p = 0.041). The results of this study indicate that a relationship between IVDD and AR expression exists. Thus, the SNS and its neurotransmitters might play a role in IVDD pathogenesis. The knowledge of differential AR expression in different etiologies could contribute to the development of new therapeutic approaches for IVDD.

177. The influence of hospital type, insurance type and patient income on 30-day complication and readmission rates following lumbar spine fusion

177. The influence of hospital type, insurance type and patient income on 30-day complication and readmission rates following lumbar spine fusion