Herniated Nucleus Pulposus Research Articles

The Comparison of Trace Element Levels in Serum, Bone and Intervertebral Disc Tissues of Patients with Lumbar Spinal Stenosis and Lumbar Disc Herniation

The Comparison of Trace Element Levels in Serum, Bone and Intervertebral Disc Tissues of Patients with Lumbar Spinal Stenosis and Lumbar Disc Herniation

The role of single nucleotide polymorphisms of IL-1A -889C>T (rs1800587), TNF-A -238G>A (rs361525), and VDR TaqI (rs731236) on susceptibility to herniated nucleus pulposus: a systematic review and meta-analysis.

Background: The pathogenesis of herniated nucleus pulposus (HNP) is complex and may involve the wide variety of gene polymorphism. However, the reports from the existing studies are inconclusive. The objective of this study was to determine the role of single nucleotide polymorphisms (SNPs) in interleukin 1 alpha ( IL-1A), tumor necrosis factor-alpha ( TNF-A), and vitamin D receptor ( VDR) genes on the susceptibility to herniated nucleus pulposus (HNP). Methods: Four databases (PubMed, Embase, Cochrane, and Web of Science) were searched as of April 1 st, 2021. Authors, publication year, targeted genes, genotype and allele frequency in each case and control groups were collected. Newcastle-Ottawa scale was used to evaluate the publication quality. The pooled estimates of association of IL-1A -889C>T (rs1800587), TNF-A -238G>A (rs361525), and VDR TaqI (rs731236) and susceptibility to HNP were assessed using Z test. Results: We screened 3,067 unique studies for eligibility and three, two and nine case-controlstudies on IL-1A -889C>T, TNF-A -238G>A, and VDR TaqI were included, respectively, in our meta-analysis. The studies consisting 369 HNP cases and 433 controls for IL-1A -889C>T, 252 cases and 259 controls for TNF-A -238G>A and 1130 cases and 2096 controls for VDR TaqI. Our pooled estimates indicated that there was no significant association of those SNPs with the susceptibility to HNP in any genotype, dominant model, recessive model, or allele comparations. Conclusion: Although individual studies suggested the important role of gene expression dysregulation associated with SNPs in IL-1A, TNF-A, and VDR, our data indicated that IL-1A -889C>T, TNF-A -238G>A, and VDR TaqI had weak association with HNP susceptibility in both genotypes and allele distributions. However, since heterogeneity was identified among studies included in this meta-analysis, further meta-analysis with a larger population and subgroup analysis on specific population are warranted to support this finding.

Barricaid Spinal Implant Device

Horizon Scan reports provide brief summaries of information regarding new and emerging health technologies. These technologies are identified through the CADTH Horizon Scanning Service as topics of potential interest to health care decision-makers in Canada. This Horizon Scan summarizes the available information regarding an emerging technology, Barricaid — a spinal implant device for those at risk of recurrent spinal disc herniation.

P40. Indirect effect on adjacent segment after minimally invasive transforaminal lumbar interbody fusion

<h3>BACKGROUND CONTEXT</h3> MIS-TLIF is an alternative treatment for degenerative spine disease, which aims to decompress and stabilize the most stenotic level correlating with clinical symptoms, while sparing the less severe adjacent segments. According to previous studies, interbody fusion was reported to not only affect the fused level, but also the adjacent segments. These effects might cause changes in canal dimensions at the adjacent segments, leading to unsatisfactory postoperative symptoms. <h3>PURPOSE</h3> The goal of this study was to compare the dural sac area and other canal dimension parameters on MRI at the adjacent segments before and after minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF), including the change in segmental and regional parameters measured on plain radiograph. <h3>STUDY DESIGN/SETTING</h3> Retrospective cohort study King Chulalongkorn Memorial Hospital. <h3>PATIENT SAMPLE</h3> Patients who underwent MIS-TLIF at L4/5 level in King Chulalongkorn Memorial Hospital The indications for surgery were spinal canal stenosis, herniated nucleus pulposus, and spondylolisthesis grade 1-2. <h3>OUTCOME MEASURES</h3> MR image parameters: dural sac area (DSA), sagittal spinal AP diameter (SAPD), ligamentum flavum area (LFA), ligamentum flavum thickness (LFT), foraminal area (FA), foraminal height (FH), at the adjacent segments of fused level. Standing lateral plain radiograph: disc height (DH), segmental angle (SA) of adjacent segments and fused level lumbar lordosis (LL) <h3>METHODS</h3> Forty-four patients who underwent MIS-TLIF at L4/5 level were examined. The indications for surgery were spinal canal stenosis, herniated nucleus pulposus, and spondylolisthesis grade 1-2. We reviewed their standing plain radiograph and MR image parameters, including dural sac area (DSA), sagittal spinal AP diameter (SAPD), ligamentum flavum area (LFA), ligamentum flavum thickness (LFT), foraminal area (FA), foraminal height (FH), disc height (DH), segmental angle (SA), and lumbar lordosis (LL) at the adjacent segments of fused level. Disc height and segmental angle at fused level was also reviewed. All parameters were compared before, and 3 months postoperatively. <h3>RESULTS</h3> The mean (SD) pre- and postoperative DSA at upper adjacent segment was 125.12 (35.72) and 133.17 (35.07) mm2, while pre- and postoperative DSA at lower adjacent segment was 103.58 (44.32) and 117.66 (46.34) mm2 respectively. The postoperative DSA significantly increased in the upper (mean change 8.05 (95%CI 4.44-11.66) mm2, P <0.001) and lower (14.08 (95%CI 9.47 – 18.69) mm2; P <0.001) adjacent segments. Eleven (25%) and 22 (25%) patients had preoperative upper adjacent segment areas <100 mm2 and ≥100 mm2respectively. The mean change in DSA was greater in patients with preoperative DSA <100 mm2 versus ≥100 mm2, but the difference was more pronounced in the upper versus the lower adjacent segment (4.3 (95%CI -4 to 12.7) mm2; P = 0.30 versus 1.1 (95%CI -8.3 to 10.4); P = 0.82, respectively). Significant increases in SAPD were also seen in both upper (0.85 (95%CI 0.45 to 1.25 mm; P <0.001) and lower (0.66 (95%CI 0.34 to 0.97) mm; P<0.001) adjacent segments. LFT significantly decreased in the lower adjacent segment (-0.37 (95%CI -0.62 to -0.11) mm; P=0.006); a small but non-significant decrease was also observed in the upper adjacent segment (-0.1 (95%CI -0.37 to 0.17) mm; P=0.47). No other significant changes in other canal dimensions were noted. <h3>CONCLUSIONS</h3> Adjacent segment DSA increased significantly after MIS-TLIF. In addition, other parameters representing canal dimension (SAPD, LFT) also significantly changed after the operation. Further studies are needed to assess the relationship between these changes and postoperative clinical outcomes. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

253. Mental health improvement predicts acute changes in physical health outcomes following minimally invasive lumbar decompression

<h3>BACKGROUND CONTEXT</h3> Previous studies have assessed the impact of preoperative depressive symptoms on postoperative outcomes with inconsistent results. However, the influence of postoperative improvement in depression has not been assessed in terms of other patient-reported outcomes. <h3>PURPOSE</h3> To assess the association between improvement in depressive symptoms and other postoperative outcomes following minimally invasive lumbar decompression (MIS LD). <h3>STUDY DESIGN/SETTING</h3> Retrospective cohort. <h3>PATIENT SAMPLE</h3> A total of 193 patients undergoing primary, elective, single level MIS LD procedures. <h3>OUTCOME MEASURES</h3> Demographic and perioperative characteristics, Patient Health Questionnaire-9 (PHQ-9), Patient-Reported Outcomes Measurement Information System physical function (PROMIS PF), 12-Item Short Form Physical Composite Score (SF-12 PCS), Oswestry Disability Index (ODI), visual analog scale (VAS) back and VAS leg. <h3>METHODS</h3> Prospectively collected data were recorded in a private surgical database and reviewed for primary, elective, single level MIS LD procedures. Patients lacking pre- or postoperative PHQ-9 data or whose procedures were indicated due to infection, malignancy, or trauma were excluded. Descriptive statistics were performed for patient demographics, preoperative spinal pathology, and perioperative characteristics. Patient reported outcome measures (PROMs) were administered at preoperative and 6-week, 12-week, 6-month, 1-year and 2-year postoperative timepoints. PROMs included PHQ-9, PROMIS PF, SF-12 PCS, ODI, VAS back and VAS leg. Delta (Δ) scores were calculated for each PROM based on postoperative improvement from preoperative baseline values. Achievement of a minimum clinically important difference (MCID) was determined by comparing Δ scores to the following previously established threshold values: AS back (2.2), VAS leg (5.0), ODI (8.2), SF-12 PCS (2.5), PROMIS PF (4.5). Postoperative improvement in PROM scores from preoperative baseline was assessed using a paired Student's t-test. Correlation between ΔPHQ-9 and other ΔPROM scores was assessed using Pearson's correlation coefficient. Multivariate regression analysis was used to assess PHQ-9 MCID achievement as a predictor of MCID achievement for other PROMs. <h3>RESULTS</h3> A total of 193 patients met inclusion/exclusion criteria. The study cohort had a mean age of 44.0 years, 72.0% were male, and the mean body mass index was 29.5 kg/m2. Herniated nucleus pulposus was the most common preoperative spinal pathology (92.8%). Mean perioperative characteristics were as follows: operative duration 39.8 minutes, estimated blood loss 25.6 mL and postoperative length of stay 4.8 hours. All PROMs demonstrated significant postoperative improvement from preoperative baseline (p≤0.012), with the exception of PHQ-9 at 2-years (p=0.248). ΔPHQ-9 was significant correlated with ΔPROMIS at 12-weeks through 1-year (all p≤0.002), ΔSF-12 PCS at 6-weeks through 1-year (all p≤0.018), ODI from 6-weeks through 6-months (all p≤0.024), VAS back at 6-weeks and 2-years (both p≤0.033), and VAS leg at 6-weeks only (p=0.009). Multivariate analysis revealed PHQ-9 MCID achievement as a significant predictor of MCID achievement in other PROMs at 12-weeks (p=0.005), 6-months (p<0.001) and overall (p=0.002). <h3>CONCLUSIONS</h3> Improvement in depressive symptoms, as measured by PHQ-9, was significantly associated with improvement in other PROMs primarily at short-term and intermediate postoperative timepoints. Therefore, lessening of depressive symptoms may be a particularly pertinent factor for overall outcomes in the first few months following MIS LD procedures. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

P121. Utilizing double machine learning to discern risk factors for preoperative depression among anterior cervical discectomy and fusion (ACDF) patients

<h3>BACKGROUND CONTEXT</h3> The Patient Health Questionnaire-9 (PHQ-9) is a common instrument for assessing depressive symptoms and has been validated in numerous patient populations. Cross-fitting or double machine learning (ML) is a method of variable selection that has gained increased attention for its potential to identify coefficients of interest. Among patients undergoing anterior cervical discectomy and fusion (ACDF), a better understanding of the factors associated with greater depressive symptoms may assist in identifying patients who could benefit the most from management of depressive symptoms prior to surgical intervention. <h3>PURPOSE</h3> In this study, we use ML to assess and identify the most significant risk factors associated with moderately severe depressive symptoms (PHQ-9≥15) among patients undergoing ACDF. <h3>STUDY DESIGN/SETTING</h3> Retrospective Cohort. <h3>PATIENT SAMPLE</h3> A total of 147 patients who underwent single or multilevel ACDF procedures. <h3>OUTCOME MEASURES</h3> Demographic and baseline characteristics, pain levels (Visual Analog Scale [VAS] arm and neck pain). <h3>METHODS</h3> We conducted a retrospective review of patients undergoing single or multilevel ACDF between 2016 and 2019. We excluded patients if they underwent surgery due to infection, metastasis or trauma. Demographic and baseline characteristics were recorded. We recorded degenerative spinal diagnoses and symptoms and postoperative complications. We assessed demographics, baseline characteristics, pain levels (Visual Analog Scale [VAS] arm and neck pain) and spine pathologies with a bivariate analysis to explore how much they elevated the risk of preoperative depression. We used a cross-fit partialling-out least absolute shrinkage and selection operator (LASSO) logistic regression to estimate odds ratios (OR), confidence intervals, and to adequately control for and select significant covariates contributing to increased levels of preoperative depression. <h3>RESULTS</h3> There were 147 patients who underwent single or multilevel ACDF procedures. The cohort was 59% female, 43% had an elevated body mass index (BMI) and 16% had a smoking history. Other comorbidities included hypertension (29.3%), diabetes (12.2%), arm pain (49.7%) and neck pain (48.3%). The rate of moderately severe baseline depressive symptoms (PHQ-9≥15) was 16.3%. The most common preoperative spinal pathologies and symptoms included myeloradiculopathy (90.5%), herniated nucleus pulposus (82.3%), weakness (8.8%) and radiculopathy (6.8%). The only postoperative complication was urinary retention (1.4%). Both urinary retention cases required brief catheter replacement and were resolved prior to discharge. On bivariate analysis, significant baseline characteristics associated with higher levels of preoperative depression (PHQ-9 ≥ 15) included: BMI ≥30 kg/m2 (OR = 2.2, p = 0.040), WC insurance (OR = 2.2, p = 0.035), VAS arm pain ≥7 (OR = 2.5, p = 0.032), and VAS neck pain ≥7 (OR = 4.1, p = 0.003). Our cross-fit partialing-out LASSO regression revealed VAS neck pain ≥7 (OR = 6.8, p = 0.002) and BMI ≥30 kg/m2 (OR = 3.0, p = 0.034) as potentially significant risk factors for preoperative depression severity. <h3>CONCLUSIONS</h3> Our study utilized DML to identify risk factors associated with elevated levels of preoperative depression among patients undergoing single or multilevel ACDFs. The most significant risk factors associated with moderately severe depression included increased neck pain and BMI. Further investigations are needed to identify potential ACDF outcomes and complications that are most associated with increased levels of preoperative depression influences. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

150. The effect of online prescription drug monitoring on opioid prescription habits after single level lumbar fusion

<h3>BACKGROUND CONTEXT</h3> The United States opioid epidemic is a well-documented crisis stemming from increased prescription of narcotics, leading to widespread misuse of both prescription and nonprescription opioid pain relievers. To combat this epidemic, online prescription drug monitoring programs (PDMPs) have been implemented at the state level to track prescriptions of controlled substances and mitigate potential misuse and addiction. <h3>PURPOSE</h3> To evaluate prescription trends of opioids over time following implementation of an online PDMP in patients who underwent single-level lumbar fusion. <h3>STUDY DESIGN/SETTING</h3> Retrospective cohort analysis. <h3>PATIENT SAMPLE</h3> Patients 18 years of age or older who underwent single-level lumbar fusion for spinal stenosis, spondylolisthesis, or disc herniation. <h3>OUTCOME MEASURES</h3> Pre- and postoperative per-patient average total opioid prescriptions, prescriptions obtained by private pay, number of prescribers, number of pharmacies, number of pills/liquid doses, refills, duration of use (days), total milligram morphine equivalents (MME) per patient, preoperative opioid naivety (defined as no documented opioid prescription within one year prior to surgery), and postoperative chronic opioid use (defined as filling ten or more prescriptions, or receiving 120 or more days of opioid prescriptions, within the first year after surgery excluding the initial 90-day postoperative period). <h3>Methods</h3> Patients who underwent single-level lumbar fusion between January 1st, 2017 and December 30, 2019 were identified. Patients were placed into one of two cohorts: (1) patients whose procedure occurred during 2017, the first calendar year following implementation of the local online PDMP, and (2) patients whose procedures occurred during 2019. Opioid use data was obtained by searching for each patient in the state government's online PDMP and recording data within the year prior to and the year following the patient's procedure. <h3>Results</h3> A total of 393 patients were included in the study. One hundred seventy-two were included in the 2017 cohort, while 221 were included in the 2019 cohort. Preoperatively, the 2019 cohort obtained significantly greater average of preoperative prescription opioids via private pay compared to 2017 (0.4 ± 1.5 vs 0.1 ± 1.6, p=0.01). Postoperatively, the 2019 cohort obtained on average a greater total number of opioid prescriptions (4.0 ± 6.1 vs 2.8 ± 4.9, p=0.046), and obtained opioid prescriptions from a greater average number of prescribers (1.8 ± 1.4 vs 1.4 ± 1.6, p=0.01) and pharmacies (1.1 ± 0.7 vs 0.8 ± 0.8, p=0.001). <h3>Conclusions</h3> Despite implementation of an online PDMP, increases were found from 2017 to 2019 in per-patient preoperative prescriptions obtained by private pay as well as average total postoperative opioid prescriptions and average number of prescribers and pharmacies. While the exact effect of different strategies aimed at decreasing the misuse and abuse of narcotic medications is unclear, use of an online PDMP is not sufficient to discourage opioid use in patients undergoing single-level lumbar fusion. Future studies should determine the effect of other strategies, such as pain management modalities that do not involve opioid prescriptions, on discouraging opioid abuse. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

P119. Does the use of IV tranexamic acid impact postoperative hemoglobin and hematocrit following anterior cervical discectomy and fusion?

<h3>BACKGROUND CONTEXT</h3> Spinal surgery is often complicated by significant blood loss which can lead to increased patient morbidity and mortality. Tranexamic acid (TXA) is a synthetic antifibrinolytic agent that has shown promise in decreasing blood loss as well as need for postoperative blood transfusion when given during surgery. <h3>PURPOSE</h3> Recent studies have begun to report on the benefits of TXA when given perioperatively during spinal surgery2. Few studies, however, have looked at the effects of TXA in patients undergoing anterior cervical discectomy and fusion (ACDF). In this study we aimed to evaluate the effectiveness of TXA in reducing intraoperative blood loss in a cohort of ACDF patients. <h3>STUDY DESIGN/SETTING</h3> Retrospective, single-surgeon study at academic medical center. <h3>PATIENT SAMPLE</h3> All patients who underwent primary ACDF during this time either with or without the augment of TXA were included. <h3>OUTCOME MEASURES</h3> The mean differences in intraoperative blood loss as well as the change from pre to post-surgical hemoglobin and hematocrit, measured at presurgical testing 1 week prior to surgery and on postop day 1 were analyzed in TXA-treated patients compared to non-TXA-treated patients. Additionally, the number of patients requiring postoperative drain and average drain output on postoperative day #1 were measured. Mean length of stay in between groups was also analyzed. This study was subject to IRB approval. <h3>METHODS</h3> Medical records for all patients who underwent primary ACDF with a single surgeon at a tertiary center over a 3-year period from September 2016-October 2019 were evaluated retrospectively. <h3>RESULTS</h3> A total of 83 patients underwent primary ACDF during the study period. Three additional patients who underwent revision of ACDF were excluded for the purposes of this study. Of the 83 patients who underwent primary ACDF, 14 received TXA perioperatively while 69 did not receive TXA. Preoperative diagnoses included spinal stenosis, disc herniation, and spondylolisthesis. Distribution of diagnoses was equal among study groups. Patient demographics and comorbidities including age, BMI, cardiovascular disease, respiratory disease, diabetes and smoking status were evaluated and there were no significant differences between groups. Patients who received TXA had significantly lower mean operative blood loss than the non-TXA patients (41.1mL vs 77.4mL p<.05). There was, however, no significant difference in postoperative drop in hemoglobin (0.7 vs 1.0, p=.332) or hematocrit (0.0, 1.8, p=.392) between the two groups. A total of 49 patients in the non-TXA group (71%) required drain placement while 6 patients in the TXA group (43%) had a drain placed (p=.062). There was a trend towards decreased drain output on postop day 1 in the TXA group compared to the non-TXA group (32.3mL vs 40.8mL, p=.056), however it was not significant. There was also no significant difference in average length of stay between TXA and non-TXA patients (3.2 vs 3.6 days, p=.564). <h3>CONCLUSIONS</h3> TXA has been reported as a useful perioperative tool to decrease bleeding associated with spinal surgery. We found in our patients who underwent ACDF that intraoperative use of IV TXA led to a significant decrease in intraoperative blood loss, however, there was no difference in the change in pre and postoperative hemoglobin and hematocrit between ACDF patients who received TXA and those who did not. There was also no difference in mean postoperative length-of-stay between the TXA and non-TXA groups. Additionally, while not significant, there was a trend towards TXA patients being less likely to require a drain postoperatively (p=.062) and those requiring a drain having less output in the early postoperative period (p=.056). While use of TXA perioperatively for ACDF was shown in this study to decrease operative blood loss, this change was not reflected in surgical hemoglobin change or overall length of stay. Further analysis of the benefits of TXA on bleeding in ACDF patients is warranted. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

P140. Risk factors for index level fusion following lumbar microdiscectomy

<h3>BACKGROUND CONTEXT</h3> Lumbar microdiscectomy is the most commonly performed surgery for treatment of radicular pain resulting from lumbar disc herniations. A growing body of evidence has demonstrated the clinical benefit compared to nonoperative interventions, including rapid recovery, symptom improvement and high patient satisfaction. Index level fusion following microdiscectomy, however, has not been well addressed in the literature. <h3>PURPOSE</h3> The purpose of this study was to identify risk factors for index level fusion following single level lumbar microdiscectomy. <h3>METHODS</h3> Retrospective review of patients undergoing primary single level lumbar microdiscectomy at a single institution with at least 6-month follow-up. Demographics, comorbidities, radiographic parameters and intraoperative variables were assessed. Patients undergoing index level fusion following discectomy were compared to those undergoing discectomy alone using independent t-test and chi square analysis for continuous and categorical variables, respectively. Multivariate analysis was also done using a logistic regression model. Significance was set as p < 0.05. <h3>RESULTS</h3> A total of 1,805 patients were identified for inclusion in analysis. This included 74 patients with eventual index level fusion and 1731 patients with discectomy alone. The fusion rate following primary lumbar discectomy was 4.1%, which occurred on average at 35.55 months (± 37.55 months). Patient-related risk factors include history of smoking, diabetes mellitus, and obesity (p<0.001), as well as a history of substance abuse (p<0.020). Gender and duration of symptoms was not found to be significantly different between the two groups. Patients undergoing fusion had higher rates of coronal deformity (p<0.001) and radiographic instability including listhesis and lateral subluxation, however no difference in spinopelvic parameters was noted. Patients undergoing tubular discectomy had lower rates of fusion compared to a mini-open approach (p<0.001). The overall revision discectomy rate was 5.42%, and this was not predictive of the likelihood of fusion (5.41% vs 5.42%, p=0.99). Following multivariate analysis significant risk factors included age, workers' compensation status, obesity, substance use, scoliosis, retrolisthesis, and mini-open approach. <h3>CONCLUSIONS</h3> In a large cohort of patients undergoing lumbar discectomy for herniated nucleus pulposus, the risk of subsequent index level fusion was 4.1%. Potential risk factors for eventual fusion include patient related factors such as smoking, diabetes and obesity, radiographic evidence of spinal instability or coronal deformity, and surgical approach. While reherniation requiring revision discectomy may necessitate the eventual need for fusion, revision discectomy alone may not be an independent risk factor. This is a preliminary study, however, and prospective studies with a larger number of patients with long-term follow-up is necessary to investigate and validate these potential risk factors. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

93. Differences in patient reported outcomes between patients who do and do not complete PROMIS surveys

<h3>BACKGROUND CONTEXT</h3> Patient-Reported Outcomes Measurement Information System (PROMIS) has been well validated as a tool for assessing patient reported outcomes in spine surgery. However, as with any self-reported survey, PROMIS is vulnerable to response bias. There is currently a dearth of literature assessing differences in patients who do and do not complete PROMIS surveys. <h3>PURPOSE</h3> To characterize differences in patient reported outcome measure (PROM) scores between patients who do and do not complete PROMIS physical function (PF) surveys following lumbar spine surgery. <h3>STUDY DESIGN/SETTING</h3> Retrospective cohort. <h3>PATIENT SAMPLE</h3> A total of 983 patients undergoing primary lumbar spine procedures. <h3>OUTCOME MEASURES</h3> Demographic and perioperative characteristics, Patient Health Questionnaire (PHQ-9), visual analog score (VAS) back and leg, Oswestry Disability Index (ODI) and 12-Item Short Form Physical Composite Summary (SF-12 PCS) <h3>METHODS</h3> A prospectively maintained surgical database was retrospectively reviewed for primary lumbar spine procedures from May 2015 to July 2020. Procedures indicated for traumatic, infectious, or malignant etiologies were excluded. Patient demographic and operative data were collected. Outcome measures for PHQ-9, VAS back and leg, ODI and SF-12 PCS were recorded at both pre- and postoperative (6-week, 12-week, 6-month, 1-year, 2-year) timepoints. Completion rates for PROMIS PF surveys were recorded for each of the above timepoints. PROMIS PF survey dates that were before or after the window when patients could have potentially completed the survey (eg, ≤1 year after study start or before study end for 1-year PROMIS surveys) were excluded from this analysis. Descriptive statistics were performed for demographic and operative variables. Patients were categorized into groups at each timepoint based on whether or not PROMIS PF was completed. A t-test for independent samples was used to determine differences in mean scores for each PROM at each timepoint between groups. <h3>RESULTS</h3> A total of 983 patients were included in this study with an average age of 48.8 years. A majority were male (66.5%), had a body mass index <30 kg/m2 (60.0%), and were nonsmokers (88.3%). The most common spinal pathology was recurrent herniated nucleus pulposus at 53.2%. Means values for operative variables were 86.6 minutes for operative time, 42.8mL for estimated blood loss, and 18.0 hours for length of stay. No significant differences were observed for all outcome measures between PROMIS completion groups at the preoperative timepoint. PHQ-9 and VAS back scores differed significantly between groups through 1-year (all p<0.05). Significant differences in VAS leg and ODI scores were demonstrated through 6-months (all p<0.05), but not at 1-year. SF-12 PCS differed significantly between PROMIS completion groups only at 6-weeks (p=0.018). <h3>CONCLUSIONS</h3> Patients who did not complete PROMIS PF surveys had significantly poorer outcomes than those that did in terms of postoperative depressive symptoms, pain, and disability. These results suggest that patents completing PROMIS questionnaires may represent a healthier cohort than the overall lumbar spine population. Interestingly, these differences were not observed for preoperative scores and to a lesser extent for physical function. This finding may be reassuring, since PROMIS PF's primary function is to assess patient physical function. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

50. Re-emergence of depressive symptoms and associated risk factors in cervical spine patients

<h3>BACKGROUND CONTEXT</h3> Few studies have investigated worsening of depressive symptoms following cervical spine procedures such as anterior cervical discectomy and fusion (ACDF) or cervical disc arthroplasty (CDA). <h3>PURPOSE</h3> To evaluate risk factors associated with worsening depressive symptoms following ACDF or CDA. <h3>STUDY DESIGN/SETTING</h3> Retrospective cohort. <h3>PATIENT SAMPLE</h3> A total of 362 patients undergoing primary, elective, single or multilevel ACDF or CDA procedures. <h3>OUTCOME MEASURES</h3> Demographics, perioperative information, Short Form 12-Item and Veterans RAND Mental Component Summary (SF-12 and VR-12 MCS), Patient Health Questionnaire-9 (PHQ-9), visual analog scale (VAS) for neck and arm, and Neck Disability Index (NDI). <h3>METHODS</h3> A surgical registry was retrospectively reviewed for primary, elective, single or multilevel ACDF or CDA procedures. Demographics and perioperative information were collected and descriptive statistics performed. SF-12 and VR-12 MCS, PHQ-9, VAS for neck and arm, and NDI were collected preoperatively and at 6-weeks, 12-weeks, 6-months, and 1-year postoperatively. Improvement of all outcome measures from preoperative values was evaluated using paired student's t-test. Achievement of minimum clinically important difference (MCID) was evaluated by comparing the difference in preoperative and postoperative scores with the following preestablished values: 4.7 (SF-12 MCS), 8.1 (VR-12 MCS), and 3.0 (PHQ-9). Worsening of depressive symptoms, MCID "drop-off", was defined as patients who demonstrated achievement of an MCID at an earlier postoperative timepoint and subsequently failed to achieve an MCID at a later timepoint. Bivariate poisson regression with robust error variance was performed to determine relative risk of demographic and perioperative characteristics with mental health MCID "drop-off". <h3>RESULTS</h3> Of the eligible 362 patients, mean age was 49.0 years and 58.6% were male with a mean body mass index of 29.1 kg/m2 . Preoperatively 47.2% of patients had a high level of neck pain, 43.2% with high arm pain, 12.9% with a poor PHQ-9 score and 43.9% with a poor SF-12 MCS score. Majority of patients experienced myeloradicular symptoms (81.2%) and had a spinal pathology of herniated nucleus pulposus (85.4%). Majority of procedures were performed at the single level (61.4%) with 80.4% of procedures being ACDF and 19.6% being CDA. Mean operative time was 61.9 minutes with an average estimated blood loss of 40.3mL. The study cohort had a mean length of stay of 18.7 hours. Both SF-12 MCS and PHQ-9 demonstrated significant improvements from preoperative levels at all postoperative timepoints (all p<0.01). VAS neck, VAS arm, and NDI demonstrated significant improvement at all timepoints (all p<0.001). Risk factors associated with a MCID "drop-off" for both SF-12 and VR-12 MCS included a worse preoperative SF-12 PCS (all p<0.05) and workers' compensation (p=0.012) only for SF-12 PCS. <h3>CONCLUSIONS</h3> Cervical spine patients demonstrated significant improvements in mental health, pain, disability, and physical function following cervical procedures. Worse preoperative depressive symptoms and workers' compensation were risk factors for reemergence of postoperative depression. These results may indicate that patients presenting with worse depression may be more susceptible to loss of initial improvements in mental health outcomes. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

155. Dual role of neck disability index in assessment of quality of life in cervical spine patients

<h3>BACKGROUND CONTEXT</h3> Neck disability index (NDI) is a reliable measure for disability in patients with cervical myeloradiculopathy. Few studies have examined the relationship between NDI and mental health outcomes following anterior cervical discectomy and fusion (ACDF). <h3>PURPOSE</h3> To determine the correlation between NDI and mental health outcome measures following ACDF. <h3>STUDY DESIGN/SETTING</h3> Retrospective cohort. <h3>PATIENT SAMPLE</h3> A total of 225 patients undergoing primary, single or multi-level ACDF procedures. <h3>OUTCOME MEASURES</h3> Demographic and perioperative characteristics, NDI, 12-Item Short Form Mental Component Summary (SF-12 MCS) and Patient Health Questionnaire-9 (PHQ-9) <h3>Methods</h3> A prospectively maintained surgical registry was retrospectively reviewed for consecutive elective ACDF procedures from December 2013 to December 2019. Inclusion criteria were patients undergoing elective, primary, single or multi-level ACDF. Procedures indicated for infectious, traumatic or malignant etiologies were excluded. Demographic characteristics such as age, gender, body mass index (BMI), ethnicity, smoking and diabetic status, and insurance type were collected preoperatively. Medical comorbidities and classifications were preoperatively collected as American Society of Anesthesiologists physical classification (ASA) and Charlson comorbidity index (CCI). Preoperative characteristics including spinal pathology, operative time, blood loss, length of postoperative stay and day of discharge were also collected. Primary outcomes of interest were NDI and mental health outcome measures, SF-12 MCS and PHQ-9. Outcomes were collected at the preoperative timepoint as well as postoperative timepoints (6-weeks, 12-weeks, 6-months, 1-year, 2-years). Postoperative improvement for all outcomes was evaluated using a paired Student's t-test. Correlations between NDI and mental health outcomes were evaluated using Pearson's correlation analysis. Strength of association was determined using the following criteria: weak (0.1 ≤ |r| < 0.3); moderate (0.3 ≤ |r| < 0.5); strong (|r| ≥ 0.5). <h3>Results</h3> A total of 225 patients were included in this study. Mean age was 49.8 years with majority being male (57.8%) and nonobese (60.0%). Majority of patients had a single level procedure (55.6%), a spinal pathology of recurrent herniated nucleus pulposus (79.1%) and had a mean procedure time of 56.1 minutes, length of stay of 13.9 hours, and were typically discharged by postoperative day 0. NDI demonstrated significant improvements through 2-years compared to preoperative baseline values (all p<0.001). Similarly, SF-12 MCS and PHQ-9 significantly improved through 1-year postoperatively (all p≤0.010), but was not maintained at 2-years (p=0.835; p=0.128). NDI demonstrated a significant but moderate correlation with SF-MCS at the preoperative timepoint (|r| = 0.447), but a strong correlation was observed at all postoperative timepoints (all p≤0.001). A significant and strong correlation between NDI and PHQ-9 was demonstrated at all timepoints (all p≤0.002). <h3>Conclusions</h3> NDI demonstrated significant and strong correlations with mental health outcome measures at all postoperative timepoints. NDI is an effective measure to assess neck disability from cervical myeloradiculopathy, but it may also capture the impact on mental health following ACDF. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

Predictors of the conservative management outcomes in patients with lumbar herniated nucleus pulposus: A prospective study in Indonesia

BackgroundThe objective of this study was to identify the predictors of the conservative management outcomes in patients with lumbar herniated nucleus pulposus (HNP). MethodsA prospective study was conducted between June 2010 and April 2012 in Banda Aceh, Indonesia. Clinical and baseline neurologic examinations such as passive straight leg raising test (SLRT), cross SLRT, and patellar and Achilles reflexes were assessed prior to the conservative management. The patients were evaluated at 2nd, 4th, 8th, 12th and 24th week following commencement of the conservative management. ResultsWe recruited and followed 171 HNP patients of which 35.7% of them had good outcome. At univariate analysis, patients with more than 12 months duration of complaint, those with dominant radicular pain, severe pain intensity (visual analogue scale 7–10), positive SLRT, positive cross SLRT, and reduced motor power of knee extensors (muscle strength grade 1–4), were associated with poor outcome. Multivariate analysis suggested that patients with dominant radicular type of pain were likely to had poor outcome compared to those with dominant back pain (odd ratio (OR) 10.57 with 95% confidence interval (CI) 1.15–96.93). Patients with reduced motor power of knee extensors also had a higher chance to have poor outcome compared to those who were normal (OR: 10.57; 95% CI: 1.15–96.93). ConclusionType of pain and the strength of lower extremities could be able to predict the failure of conservative management in patients with lumbar disc herniation. However, further studies with the bigger sample size are warrant to validate our results.

The role of single nucleotide polymorphisms of IL-1A -889C&gt;T (rs1800587), TNF-A -238G&gt;A (rs361525), and VDR TaqI (rs731236) on susceptibility to herniated nucleus pulposus

Background: The pathogenesis of herniated nucleus pulposus (HNP) is complex and may involve the wide variety of gene polymorphism. However, the reports from the existing studies are inconclusive. The objective of this study was to determine the role of single nucleotide polymorphisms (SNPs) in interleukin 1 alpha (IL-1A), tumor necrosis factor-alpha (TNF-A), and vitamin D receptor (VDR) genes on the susceptibility to herniated nucleus pulposus (HNP). Methods: Four databases (PubMed, Embase, Cochrane, and Web of Science) were searched as of April 1 st, 2021. Authors, publication year, targeted genes, genotype and allele frequency in each case and control groups were collected. Newcastle-Ottawa scale was used to evaluate the publication quality. The pooled estimates of association of IL-1A -889C&gt;T (rs1800587), TNF-A -238G&gt;A (rs361525), and VDR TaqI (rs731236) and susceptibility to HNP were assessed using Z test. Results: We screened 3,067 unique studies for eligibility and three, two and nine case-control studies on IL-1A -889C&gt;T, TNF-A -238G&gt;A, and VDR TaqI were included, respectively, in our meta-analysis. The studies consisting 369 HNP cases and 433 controls for IL-1A -889C&gt;T, 252 cases and 259 controls for TNF-A -238G&gt;A and 1130 cases and 2096 controls for VDR TaqI. Our pooled estimates indicated that there was no significant association of those SNPs with the susceptibility to HNP in any genotype, dominant model, recessive model, or allele comparations. Conclusion: Although individual studies suggested the important role of gene expression dysregulation associated with SNPs in IL-1A, TNF-A, and VDR, our data indicated that IL-1A -889C&gt;T, TNF-A -238G&gt;A, and VDR TaqI had weak association with HNP susceptibility in both genotypes and allele distributions. However, since heterogeneity was identified among studies included in this meta-analysis, further meta-analysis with a larger population and subgroup analysis on specific population are warranted to support this finding.

Impact of Prolonged Duration of Symptoms on Mental Health in Anterior Cervical Disectomy and Fusion Patients.

Prolonged duration of symptoms is associated with worse pain and disability in patients undergoing anterior cervical discectomy and fusion (ACDF). Our study aims to determine the effect of symptom duration on severity of depression among ACDF patients. We retrospectively reviewed a prospective surgical database from 2006 to 2019 for primary, single, or multilevel ACDF. Patients missing the duration of symptom information or patient-reported outcome measures (PROMs) were excluded. PROMs included Patient Health Questionnaire-9, 12-Item Short Form Mental Component Score, and 12-Item Veterans RAND Mental Component Score and were collected at preoperative, 6-week, 12-week, 6-month, 1-year, and 2-year timepoints. The minimum clinically important difference (MCID) was calculated using the established values. Patients were categorized based on preoperative duration of symptoms as follows: <6 months, ≥6 months and <1 year, 1 to 2 years, and >2 years. Univariate analysis was done to determine differences in demographics and perioperative characteristics. Intergroup differences in PROMs and MCID achievement were evaluated using linear regression and logistic regression, respectively. Two hundred thirty-one ACDF patients included had a mean age of 49.6 years and most were male (61.0%) and nonobese (<30 kg/m2; 55.0%). The groups differed by their American Society of Anesthesiologists classification (P = 0.029), workers' compensation status (P = 0.022), and diagnosis of herniated nucleus pulposus (P = 0.010). Postoperative mental health outcomes did not significantly differ between duration groups except for Veterans Rand-12 Mental Component Score at 12 weeks (P = 0.044). MCID achievement rates did not significantly differ. Patients undergoing ACDF largely did not demonstrate differences in mental health scores or achievement of MCID based on the duration of symptoms.

Risk Factors for Recurrence of Disc Herniation After Single-Level Lumbar Discectomy

Objective: Herniated nucleus pulposus is a common disease of the lumbar spine. Recurrence of disc herniation and subsequent disc degeneration are the most common problems following discectomy. Many first-time lumbar discectomy patients experience favorable outcomes; however, same-level recurrent discectomy can occasionally induce unfavorable results. Therefore, in this study, we retrospectively analyzed the risk factors for recurrence of lumbar disc herniation after discectomy.Methods: From January 2013 to December 2015, 226 patients underwent one-level discectomy in our department. We excluded patients with less than two years of follow-up, a previous spine deformity with a compression fracture, foraminal or extraforaminal discs, or a history of previous lumbar operation history, leaving 71 selected patients. Patients were divided into recurrent and non-recurrent groups and various factors were retrospectively compared between the groups.Results: Patients with preoperative disc space narrowing experienced recurrence less commonly; however, this was not statistically significant (10.0% and 25.5%, respectively; p=0.150). A disc height decrease of more than 20% during the follow-up period was a statistically significant risk factor for recurrence (36.4% and 14.3%, respectively; p=0.035), and grades 3 and 4, compared to grades 1 and 2, facet joint degeneration were also statistically significant risk factors for recurrence of disc herniation (41.2% and 14.8%, respectively; p=0.020).Conclusion: Patients who underwent more than a moderate degree of preoperative facet joint degeneration on the operated side and for whom the progression of disc space height decreased during the follow-up period may require closer observation for recurrence of disc herniation.

Spinal epidural arteriovenous fistula with intradural venous reflux: The possibility of acquired origin caused by spinal stenosis and/or disc herniation

BackgroundSpinal epidural arteriovenous fistulas (SEAVFs) are relative rare lesions. The pathogenesis of these fistulas remains unclear. Our aim is to review cases of SEAVFs at our institution. MethodsWe reviewed a consecutive series of spinal vascular disease at our institution and collected all patients harboring SEAVFs. Medical charts were retrospectively reviewed regarding patient demographic data (i.e., gender and age), presenting symptoms and signs, previous history of spinal surgery or trauma, treatment methods, and neurological outcome after treatment. All image studies, including plain radiography, spinal MRI, MRA, and angiography were analyzed. ResultsWe identified 9 cases of lumbosacral SEAVFs with intradural venous reflux treated at our institution from June 2010 to August 2020. Their median age was 67 years, range 52–83 years. Only one patient had a history of trauma. Interestingly, our observations found that all fistulas are associated with spinal stenosis and/or disc herniation. An additional literature search about SEAVFs coexisting with spinal stenosis and/or disc herniation was performed and found another 19 cases with median age 69 years, range 39–83 years. Only 2 patients had a history of previous spinal surgery. The level of shunted pouch in all 28 patients was correlated with the level of spinal canal stenosis and/or disc herniation. Conclusions: Our study may provide an additional evidence supporting an acquired etiology of SEAVFs, which mainly manifest in late adulthood. It is possible that spinal stenosis and/or disc herniation may result in thrombosis or impairment of venous drainage, causing increased venous pressure, leading to fistulous formation.

Application of spectral subtraction denoising on 3 T MRI in lumbar spine (herniated nucleus pulposus case) GRAPPA to improve CNR

Using of r-factor which is higher can speed up the scanning time in parallel imaging techniques but causes a decrease in contrast to noise ratio (CNR), thus causing image quality not optimal in the MRI Lumbar examination of the T2WI turbo spin echo (TSE) generalized autocalibrating partially parallel acqusitions (GRAPPA) herniated nucleus pulposus case. Fast scanning time is needed by using a higher r-factor to get the optimal image with improved CNR. Spectral subtraction denoising (SSD) is one of filter technique that can be used to improve image quality, CNR is one of the parameters used in determine image quality, SSD is expected to be able improved CNR to have good image quality. The purpose was to measure changes of image quality CNR. This type of research is a pre-experimental research with a one group pretest-posttest design to determine the differences in CNR quality by applying SSD to the r-factor variations in the lumbar MRI image of T2WI TSE GRAPPA sagital. Data were analyzed by statistical tests, friedman. There is a difference in image quality in variations acceleration factor with increase CNR in GRAPPA parallel imaging technique with a value of p <0.05, obtained r-factor 3 as the optimal r-factor the highest mean rank value with the application of SSD.

Exploratory clinical trial on the safety and capability of dMD-001 in lumbar disc herniation: Study protocol for a first-in-human pilot study

Herniated nucleus pulposus (NP), one of the most common diseases of the spine, is surgically treated by removing the sequestered NP. However, intervertebral disc (IVD) defects may remain after discectomy, leading to inadequate tissue healing and predisposing patients to IVD degeneration. An acellular, bioresorbable, ultra-purified alginate (UPAL) gel (dMD-001) implantation system can be used to fill any IVD defects in order to prevent IVD degeneration after discectomy. This first-in-human pilot study aims to determine the feasibility, safety, and perceived patient response to a combined treatment involving discectomy and UPAL gel implantation for herniated NP. We designed a one-arm, double-centre, open-label, pilot trial. The study started in November 2018 and will run until a sample of 40 suitable participants is established. Patients aged 20–49 years, diagnosed with isolated lumbar IVD herniation and scheduled for discectomy represent suitable candidates. All eligible participants who provide informed consent undergo standard discectomy followed by UPAL gel implantation. The primary outcomes of the trial will be the feasibility and safety of the procedure. Secondary outcomes will include self-assessed clinical scores and magnetic resonance imaging-based measures of morphological and compositional quality of the IVD tissue. Initial outcomes will be published at 24 weeks. Analysis of feasibility and safety will be performed using descriptive statistics. Both intention-to-treat and per-protocol analyses of treatment trends of effectiveness will be conducted.

A rare case of multicentric eosinophilic granulocytic sarcoma as cause of hindlimb weakness and non‐regenerative anaemia in a minipig

AbstractA 6‐year‐old male, neutered minipig developed progressive hindlimb weakness and finally became recumbent. Clinical and laboratory examination revealed restricted hindlimb mobility and weight bearing with unimpaired reflexes and proprioception as well as marked non‐regenerative macrocytic anaemia, neutropenia and lymphocytopenia. Underlying bone marrow disease and haematopoietic neoplasia were assumed after exclusion of spinal disc herniation and infectious causes for anaemia. Despite stabilising therapy, the animal died 7 days later. Postmortem examination revealed multiple beige‐coloured nodules affecting many organs including the bone marrow and consisting of neoplastic round cells with intracytoplasmic eosinophilic granules. Using various histopathological stains and immunohistochemistry, the neoplastic cells were determined to be of eosinophil granulocyte origin. Granulocytic sarcoma is a rare form of myeloid neoplasia with only two published porcine cases. With the increasing popularity of minipigs as companion animals, extensive awareness and information concerning illnesses in these animals should be available to practitioners.