Methylprednisolone Following Minimally Invasive Lumbar Decompression: A Large Prospective Single-Institution Study

STUDY DESIGN

Prospective randomized.

OBJECTIVE

Intraoperative methylprednisolone is a common adjunct following microscopic laminectomy/microdiscectomy. The goal of epidural instillation is a rapid symptomatic reduction in irritation of neural elements. There is inconsistent data supporting its use intraoperatively. To understand whether this maneuver results in any clinical effect, we performed a multiyear prospective study.

SUMMARY OF BACKGROUND DATA

Previous work has demonstrated equivocal effects on pain with a suggestion of an increased risk of complication. These studies tend to suffer from small sample sizes and short follow-ups.

MATERIALS AND METHODS

Study obtained IRB approval. During the study period from 2013 to 2019, nearly equivalent numbers of patients who had received steroids during MIS decompressions were followed. Primary outcomes included pain (visual analog scale) and disability [Oswestry Disability Index (ODI)] at 2 weeks and 4 months. Secondary outcomes included complications, readmissions, and reoperation rates during the study period.

RESULTS

Four hundred eighty-six patients were followed for a mean follow-up of 5.17 years. The index case was more likely to be a revision surgery in the steroid group. Across all patients, there was no difference in pain at 2 weeks or 4 months. Disability was reduced at 2 weeks in the steroid group (ODI: 16.71 vs . 21.02, P = 0.04) but not at 4 months. By subgroup analysis, this is largely explained by ODI reduction in patients with high preoperative ODI (13.00 vs . 43.43, P = 0.03). Patients in the steroid cohort were more likely to undergo subsequent spinal surgery during the study period.

CONCLUSION

Methylprednisolone instillation is associated with a large, transient reduction in ODI for patients with high preoperative ODI; there is no measurable effect on pain. There is equivocal effect on risk of subsequent reoperation. This issue was clarified in peer review but changes did not make it to the abstract. Therefore, the technique is likely best reserved for patients with significant preoperative disability.

Multilevel Laminoplasty for CSM: Is C3 Laminectomy Better Than C3 Laminoplasty at the Superior Vertebra?

INTRODUCTION

In a multilevel cervical laminoplasty operation for patients with cervical spondylotic myelopathy (CSM), a partial or complete C3 laminectomy may be performed at the upper level instead of a C3 plated laminoplasty. It is unknown whether C3 technique above the laminoplasty affects loss of cervical lordosis or range of motion.

METHODS

Patients undergoing multilevel laminoplasty of the cervical spine (C3-C6/C7) at a single institution were retrospectively reviewed. Patients were divided into two cohorts based on surgical technique at C3: C3-C6/C7 plated laminoplasty ("C3 laminoplasty only", N = 61), C3 partial or complete laminectomy, plus C4-C6/C7 plated laminoplasty (N = 39). All patients had at least 1-year postoperative X-ray treatment.

RESULTS

Of 100 total patients, C3 laminoplasty and C3 laminectomy were equivalent in all demographic data, except for age (66.4 vs. 59.4 years, p = 0.012). None of the preoperative radiographic parameters differed between the C3 laminoplasty and C3 laminectomy cohorts: cervical lordosis (13.1° vs. 11.1°, p = 0.259), T1 slope (32.9° vs. 29.2°, p = 0.072), T1 slope-cervical lordosis (19.8° vs. 18.6°, p = 0.485), or cervical sagittal vertical axis (3.1 cm vs. 2.7 cm, p = 0.193). None of the postoperative radiographic parameters differed between the C3 laminoplasty and C3 laminectomy cohorts: cervical lordosis (9.4° vs. 11.2°, p = 0.369), T1 slope-cervical lordosis (21.7° vs. 18.1°, p = 0.126), to cervical sagittal vertical axis (3.3 cm vs. 3.6 cm, p = 0.479). In the total cohort, 31% had loss of cervical lordosis >5°. Loss of lordosis reached 5-10° (mild change) in 13% of patients and >10° (moderate change) in 18% of patients. C3 laminoplasty and C3 laminectomy cohorts did not differ with respect to no change (<5°: 65.6% vs. 74.3%, respectively), mild change (5-10°: 14.8% vs. 10.3%), and moderate change (>10°: 19.7% vs. 15.4%) in cervical lordosis, p = 0.644. When controlling for age, ordinal regression showed that surgical technique at C3 did not increase the odds of postoperative loss of cervical lordosis. C3 laminectomy versus C3 laminoplasty did not differ in the postoperative range of motion on cervical flexion-extension X-rays (23.9° vs. 21.7°, p = 0.451, N = 91).

CONCLUSION

There was no difference in postoperative loss of cervical lordosis or postoperative range of motion in patients who underwent either C3-C6/C7 plated laminoplasty or C3 laminectomy plus C4-C6/C7 plated laminoplasty.

The RNA-binding protein Adad1 is necessary for germ cell maintenance and meiosis in zebrafish

The double stranded RNA binding protein Adad1 (adenosine deaminase domain containing 1) is a member of the adenosine deaminase acting on RNAs (Adar) protein family with germ cell-specific expression. In mice, Adad1 is necessary for sperm differentiation, however its function outside of mammals has not been investigated. Here, through an N-ethyl-N-nitrosourea (ENU) based forward genetic screen, we identified an adad1 mutant zebrafish line that develops as sterile males. Further histological examination revealed complete lack of germ cells in adult mutant fish, however germ cells populated the gonad, proliferated, and entered meiosis in larval and juvenile fish. Although meiosis was initiated in adad1 mutant testes, the spermatocytes failed to progress beyond the zygotene stage. Thus, Adad1 is essential for meiosis and germline maintenance in zebrafish. We tested if spermatogonial stem cells were affected using nanos2 RNA FISH and a label retaining cell (LRC) assay, and found that the mutant testes had fewer LRCs and nanos2-expressing cells compared to wild-type siblings, suggesting that failure to maintain the spermatogonial stem cells resulted in germ cell loss by adulthood. To identify potential molecular processes regulated by Adad1, we sequenced bulk mRNA from mutants and wild-type testes and found mis-regulation of genes involved in RNA stability and modification, pointing to a potential broader role in post-transcriptional regulation. Our findings suggest that the RNA regulatory protein Adad1 is required for fertility through regulation of spermatogonial stem cell maintenance in zebrafish.

Wound complications in metastatic spine tumor patients with and without preoperative radiation

OBJECTIVE

Wound complications are a common adverse event following metastatic spine tumor surgery. Some patients with spinal metastases may first undergo radiation but eventually require spinal surgery because of either cord compression or instability. The authors compared wound complication rates in patients who had undergone surgery for metastatic disease and received preoperative radiation treatments, postoperative radiation, or no radiation.

METHODS

Records from patients treated at the University of California, San Francisco, for metastatic spine disease between 2005 and 2017 were retrospectively reviewed. Baseline characteristics were collected, including preoperative Karnofsky Performance Status (KPS), Spine Instability Neoplastic Score, total radiation dose, indication for surgery, diabetes status, time between radiation and surgery, use of perioperative chemotherapy or steroids, estimated blood loss, extent of fusion, and preoperative albumin level. Wound complication was defined as poor healing, dehiscence, or infection per the Centers for Disease Control and Prevention guidelines, within 6 months of surgery. One-way ANOVA was used to compare means across groups. Cumulative incidence analysis with competing risk methodology was used to adjust for risk of death during follow-up. Statistical analysis was performed using R software.

RESULTS

Two hundred five patients with adequate medical records were identified. Seventy patients had received preoperative radiation, 74 had received postoperative radiation within 6 months after surgery, and 61 had received no radiation at the surgical site. Wound complication rates were similar across the 3 cohorts: 14.3% (n = 10) in the group with preoperative radiation, 10.8% (n = 8) in the group that received postoperative radiation, and 11.5% (n = 7) in the group with no radiation (p = 0.773). Competing risk analysis showed a higher cumulative incidence of wound complications for the preoperative cohort, though this difference was not significant (p = 0.46). Overall, 89 patients were treated with external beam radiation therapy (EBRT), whereas 55 received stereotactic body radiation therapy (SBRT). There was no significant difference in wound complications for patients treated with EBRT (11.2%, n = 10) versus SBRT (14.5%, n = 8; p = 0.825). KPS was the only factor correlated with wound complications on univariate analysis (p = 0.03).

CONCLUSIONS

Wound complication rates did not differ across the 3 cohorts: patients treated with preoperative radiation, postoperative radiation within 6 months of surgery, or no radiation. The effect size was small for KPS and likely does not represent a clinically significant predictor of wound complications.

Adjacent Segment Vertebral Body Bone Density Changes as Measured By Hounsfield Units After Lumbar Spine Fusion

OBJECTIVE

We sought to evaluate Hounsfield units (HU) at the adjacent segment after single-level transforaminal lumbar interbody fusion (TLIF) with preoperative and postoperative computed tomography scans.

METHODS

We performed a retrospective study on a series of patients who underwent L4-5 TLIF, from 2007 to 2017, by 3 spine surgeons at our institution. One-hundred and forty-three total patients were identified, and 41 patients with minimum 1-year follow-up met inclusion criteria. HU values were measured on preoperative and postoperative computed tomography at the adjacent L3 segment and at L1 as a control arm. Lumbar lordosis, pelvic tilt, pelvic incidence, sacral slope, and sagittal vertical axis were also collected preoperatively and postoperatively.

RESULTS

Mean preoperative HU value at L3 did not differ from the postoperative value (134.11 ± 47.14 mg/cm³ vs. 141.21 ± 55.14 mg/cm³, P = 0.34). Similarly, the mean preoperative HU value at the L1 control level region of interest did not differ from the postoperative value (150.17 ± 53.91 mg/cm³ vs. 145.78 ± 58.34 mg/cm³, P = 0.634). The interrater reliability of HU measurements was satisfactory with a resulting intraclass correlation coefficient of 0.76.

CONCLUSIONS

As measured by HU, we did not observe a change in bone density or other signs of adjacent segment disease at the L3 vertebral body 12 months after L4-5 TLIF. Spinopelvic parameters were not shown to be correlated with HU changes.

SAFETY AND EFFICACY OF THYMIC PEPTIDES IN THE TREATMENT OF HOSPITALIZED COVID-19 PATIENTS IN HONDURAS

Coronavirus disease 2019 (Covid-19) active cases continue to demand the development of safe and effective treatments. This is the first clinical trial to evaluate the safety and efficacy of oral thymic peptides. ; We conducted a nonrandomized phase 2 trial with a historic control group to evaluate the safety and efficacy of a daily 250-mg oral dose of thymic peptides in the treatment of hospitalized Covid-19 patients. Comparisons based on standard care from registry data were performed after propensity score matching. The primary outcomes were survival, time to recovery, and number of participants with treatment-related adverse events or side effects by day 20. ; A total of 44 patients were analyzed in this study: 22 in the thymic peptide group and 22 in the standard care group. There were no deaths in the intervention group compared to 24% mortality in standard care by day 20 (log-rank P=0.02). Kaplan-Meier analysis showed a significantly shorter time to recovery by day 20 in the thymic peptide group than in the standard care group (median, 6 days vs. 12 days; hazard ratio for recovery, 2.75 [95% confidence interval, 1.34 to 5.62]; log-rank P=0.002). No side effects or adverse events were reported. ; In patients hospitalized with Covid-19, the use of thymic peptides resulted in no side effects, adverse events, or deaths by day 20. Compared with the registry data, a significantly shorter time to recovery and mortality reduction were measured.

OP0288 IMPACT OF CARDIOVASCULAR RISK ON THE DIAGNOSTIC ACCURACY OF THE ULTRASOUND HALO SCORE FOR GIANT CELL ARTERITIS

Background

The ultrasonographic (US) Halo Score provide a quantitative measure of the extent of vascular inflammation in patients with giant cell arteritis (GCA). High Halo Scores correlate with systemic markers of inflammation, rate of ocular ischaemia and may help to firmly diagnose GCA with high specificity. However, an increase in the intima media thickness (IMT) in patients with elevated cardiovascular risk (CVR) may lead to false-positive US findings.

Objectives

Our aim is to evaluate the impact of CVR on the diagnostic accuracy of the US Halo Score in patients with suspected GCA.

Methods

This is a retrospective observational study of patients suspected of having GCA and referred to our US fast track clinic. All patients underwent US exam within 24 hours per protocol. The IMT was measured in gray scale mode in cranial and extra-cranial (carotid, subclavian and axillary) arteries and the Halo Score was also determined to assess the extent of vascular inflammation. GCA diagnosis was confirmed after 6-month follow-up by the referring clinician. The European Society of Cardiology (ESC) Guidelines on CV Disease Prevention in clinical practice were used to define different categories of CVR. Patients were classified as very high, high, moderate or low CVR according to the Systemic Coronary Risk Evaluation (SCORE) obtained using the ESC CVD Risk Calculator app for mobile devices. Comparison between groups was performed and the diagnostic accuracy of the Halo Score in patients according to CVR was evaluated using ROC curves.

Results

Of the 157 patients referred to our US fast track clinic (67.5% female, mean age 73.7 years), 47(29.9%) had GCA confirmed after 6-month follow-up. There were no differences in CVR between patients with and without GCA (mean SCORE 20.6[21.6] vs 18.7[21];p=0.601). Among patients without GCA, extra-cranial artery IMT was significantly higher in patients with high/very high CVR than in those with low/moderate CVR (Table 1). The Halo Score was significantly higher in patients with high/very high CVR in non-GCA patients (9.38 (5.93) vs 6.16 (5.22);p=0.007). The area under the ROC curve of the Halo Score to identify GCA was 0.835 (CI95% 0.756-0.914), slightly greater in patients with low/moderate CVR (0.965 [CI95% 0.911-1]) versus patients with high/very high CVR (0.798[CI95% 0.702-0.895]) (Figure 1). A statistically weak positive correlation was found between the Halo Score and the SCORE (r 0.245;p=0.002).

Table 1.

Measurements of IMT in cranial and extracranial arteries and Halo Score values according to CVR

Artery IMT mm, mean (SD)Patients with GCA n=47Patients without GCA n=110Patients with high/very high CVR n=37(78.7%)Patients with low/moderate CVR n=10(21.3%)pPatients with high/very high CVR n=79(71.8%)Patients with low/moderate CVR n=31(28.2%)pSuperficial temporal artery (both)0.66(0.25)0.45(0.11)0.0250.35(0.09)0.32(0.07)0.354Frontal branch (both)0.42(0.18)0.31(0.15)0.0560.26(0.05)0.26(0.06)0.577Parietal branch (both)0.43(0.17)0.35(0.12)0.1020.27(0.04)0.28(0.08)0.173Carotid artery (both)0.88(0.21)1.2(0.6)<0.0010.83(0.16)0.74(0.13)<0.001Subclavian artery (both)0.86(0.31)1.2(0.5)0.0010.74(0.18)0.6(0.13)<0.001Axillary artery (both)0.92(0.38)1.22(0.73)0.0210.72(0.16)0.59(0.15)<0.001Halo Score, mean (SD)18.5(8.8)17.2(10.6)0.699.38(5.93)6.16(5.22)0.007Figure 1.

Diagnostic accuracy of the Halo Score for a clinical diagnosis of GCA after 6-month follow-up in (A) all GCA suspected patients, (B) patients with high/very high CVR and (C) patients with low/moderate CVR

Conclusion

High CVR may influence the diagnostic accuracy of the US Halo Score leading to false-positive findings in these patients. Higher IMT values may be found in extracranial arteries of subjects with high/very high CVR without GCA. Thus, CVR should be taken into consideration in the US vascular assessment of patients with suspected GCA. These results need to be confirmed in larger cohorts to develop a modified US Halo Score applicable to patients with high CVR.

Disclosure of Interests

None declared

Investigating SARS-CoV-2 Test Positivity Calculations Across US Jurisdictions

Purpose

Throughout the COVID-19 pandemic, many US epidemiologists and policymakers turned to an indicator called test positivity, or the percent of tests coming back positive for SARS-CoV-2, to contextualize COVID-19 case counts with testing volume. But the nation's patchworked health data infrastructure, composed of 56 systems managed by each state and territory, complicated efforts to calculate the metric in a comparable way across US jurisdictions. We set out to map jurisdictional reporting differences in test positivity and investigate whether they interfered with its effectiveness and comparability as an indicator. Understanding these differences is important because jurisdictional test positivity informed consequential policy and individuals’ understanding of risk in their communities.

Methods & Materials

We surveyed the health department websites of all US states and territories to examine how these jurisdictions were presenting test positivity on COVID-19 dashboards. When details about definitions were unavailable on jurisdictional websites, we reached out to jurisdictional public health officials for clarification. We also scored jurisdictions' presentations against best practices we identified for calculating the metric.

Results

Among the 48 states and territories posting test positivity values, we observed no consensus on how to calculate the metric—jurisdictions used different units, test types, averaging techniques, and dating schemes. By looking at data for jurisdictions that posted multiple test positivity metrics, we observed that these definitional differences could result in variations from 31% to 300%. Only four states were following all ten of the best practices for reporting test positivity.

Conclusion

The sheer number of ways states and territories define test positivity is alarming, given how much the indicator influenced US COVID-19 policy. Based on our survey, we believe the confidence of regulators in the precision and national comparability of test positivity is misplaced: The metric's value reflects state and territorial reporting decisions as much as actual viral prevalence. These findings underscore the need to invest in centralized public health infrastructure and create national reporting standards to improve unity of state reporting.

Evaluating the Quality of Federal SARS-CoV-2 Diagnostic Testing Data

Purpose

In April 2020, the US Department of Health and Human Services (HHS) and the US Centers for Disease Control and Prevention established the COVID-19 Electronic Laboratory Reporting program (CELR) to collect data on SARS-CoV-2 laboratory tests. Over the course of the following year, the federal government, partnering with the Association for Public Health Laboratories, onboarded every state to submit laboratory results to this system—the first of its kind in the US. We set out to evaluate the quality of data collected by CELR.

Methods & Materials

We compared jurisdiction-level data collected through CELR and published by HHS to the testing data published by jurisdictions on their health department webpages. Because jurisdictions define their testing data differently, we anticipated some differences from federal testing data. However, jurisdictions also tend to prioritize their dashboard reporting—since it is what is used for policy decisions like reopening—so we hypothesized that differences from federal data absent a definitional explanation could point to problems with federal data. Where we found differences between jurisdictional and federal data, we conducted interviews with public health officials to understand their cause.

Results

Of the 56 states and territories, as of April 2021 (the first month when all states were onboarded to CELR), 38 had federal total data that diverges from state data by more than 5%. Of those states, the differences of 27 could not be explained by definitional factors. Based on our interviews, we identified three problems: non-electronic reporting streams, out-of-date surveillance systems, and deduplication of laboratory data.

Conclusion

The federal testing dataset displays major unresolved quality problems, and because states present testing data so differently, state-published data forms a poor alternative to federal datasets. The federal government, which is uniquely positioned to provide testing data on infectious diseases, must work to improve the quality of laboratory data submissions by states. To support better national laboratory data, the United States should invest in updating state and laboratory data surveillance infrastructure—including updates to state surveillance systems and laboratory system updates to eliminate outdated reporting methods like faxes—and in creating more national laboratory data infrastructure.

Abstract P5-01-02: Single cell RNA transcriptomics reveals tumor promoting mammary cell subpopulation upon replication stress in BRCA1 mutant breast cancer mouse model

Women with BRCA1 (B1) mutation have an exceptionally high risk of developing breast cancer. The only effective preventive strategy currently offered to these women is the life altering prophylactic mastectomy. In light of limited treatment options available, it is critical that new therapeutic and preventive strategies be identified. Design of such strategies requires an understanding of early events in the breast cells that drive tumorigenesis. B1 heterozygous mouse models can help us identify these early changes in mammary tissue as the cells become tumor cells. However, despite the well-established association between B1 heterozygosity and cancer predisposition in humans, there are currently no such B1 mouse models that faithfully recapitulate this high risk of tumor formation. B1 heterozygous mice are not tumor-prone. This makes it difficult to use these models to study the role of B1 heterozygosity and to identify early tumor promoting changes in the breast tissue. We have now established a mouse model that induces mammary tumors in B1 heterozygous (Brca1wt/flx,Trp53flx/flx,K14cre) mice upon replication stress (RS), thus giving us a tool to study early tumor promoting changes in B1 heterozygous breast tissue. Our approach is based on our published work that reveals haploinsufficiency for RS suppression in B1 heterozygous cells. Given the importance of RS development in tumorigenesis, this effect would be a logical contributor to B1 mutant cancer development. Indeed, increasing RS in B1 heterozygous mice resulted in accelerated mammary tumorigenesis. RS in this mouse model was delivered by injecting DNA-adduct forming 4-nitroquinoline-1-oxide via mammary intraductal injection over a course of 7 weeks. RS served as an efficient and abnormally rapid driver of tumor formation (30 days post completion of injection regimen) in B1 heterozygous, but not B1 wild type mice. B1 heterozygous mice formed mammary adenocarcinoma and ductal carcinoma in-situ. Immunofluorescence based tissue section analysis and transcriptomic analysis reveals that adenocarcinomas formed in B1 heterozygous mice carry a basal epithelial phenotype like those found in human breast cancer. Such an accelerated tumor model system could prove to be invaluable in understanding the earliest events in B1 mutant breast cancer.Furthermore, our scRNAseq-based analysis has revealed early changes that occur in the breast tissue as different cell types (luminal and basal) respond to RS, and have identified new cell populations that emerge exclusively in B1 heterozygous mammary tissue undergoing RS. For this analysis, cells were collected from naïve mammary tissue, tissue collected midway through injections, and post-tumor tissue. This analysis identified a unique population of trans-differentiated cells expressing prognostic markers that have correlation to poor outcome in human breast cancer. This RS-induced mammary cell population in B1 heterozygous tissue also expresses both luminal progenitor and basal epithelial markers. Interestingly, this population was enriched for proliferation markers like Top2a, Ube2c, mKi67, and Ccnb2. Given that such proliferation markers are a hallmark of cancer stem cells, we suspect that this transdifferentiated population, which is primarily enriched in B1 heterozygous mammary tissue undergoing RS, marks some of the early cancer promoting changes in the breast tissue.Altogether, our integrative approach reveals that B1 heterozygosity in combination with RS leads to accumulation and proliferation of a specific mammary cell population that contributes to breast tumorigenesis. Identification of such early drivers is critical for the design of effective preventive and therapeutic strategies for women with B1 mutation.

Citation Format: Shailja Pathania, Joshua Rivera, Delan Khalid, Monica Manne, Stevenson Tran, Kemmie Kibaja, Carman MC Li, Joan Brugge. Single cell RNA transcriptomics reveals tumor promoting mammary cell subpopulation upon replication stress in BRCA1 mutant breast cancer mouse model [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P5-01-02.

The Preoperative Cross-sectional Area of the Deep Cervical Extensor Muscles Does Not Predict Loss of Lordosis After Cervical Laminoplasty

STUDY DESIGN

This was a retrospective, single center.

OBJECTIVES

The objective of this study was to investigate the association between the cross-sectional area (CSA) of the deep extensor muscles (DEM) and postlaminoplasty alignment.

SUMMARY OF BACKGROUND DATA

The preoperative CSA of the semispinalis cervicis (SC) has been reported to correlate with loss of lordosis (LL) after laminoplasty, with a CSA <154.5 mm2 associated with a 10 degrees LL.

METHODS

Laminoplasty patients at the University of California San Francisco between 2009 and 2018 by 2 spine surgeons were retrospectively studied. Patients with previous cervical surgery or nondegenerative diagnoses were excluded. Measurements included the C2-C7 Cobb, T1 slope, and cervical sagittal vertical axis. Preoperative DEM CSA was measured on magnetic resonance imaging. Variables associated with lordosis were analyzed with univariate analysis and multivariate logistic regression, and association between postoperative cervical alignment and the musculature was evaluated.

RESULTS

Seventy-six patients with a mean age of 64 years were included. The average follow-up was 22.53 months. The overall average CSA of the DEM was 2274.55 mm2 and that of the SC was 275.64 mm2. Means of both CSAs were higher in men (P<0.001). Linear regression showed no correlation between LL with CSA of the DEM or the SC (r=0.005, P=0.119; r=0.001, P=0.095). Univariate and multivariate regression showed no differences in the CSA of the DEM and SC between groups with and without LL (P=0.092, 0.117 and 0.163, 0.292). There was no correlation in LL with sex or body mass index (P>0.05).

CONCLUSIONS

Preoperative CSA of the deep cervical extensor muscles may not predict LL after cervical laminoplasty. The correlation between the preoperative SC CSA and postoperative cervical alignment may not be as strong as previously reported.

Does reduction of the Meyerding grade correlate with outcomes in patients undergoing decompression and fusion for grade I degenerative lumbar spondylolisthesis?

OBJECTIVE

Reduction of Meyerding grade is often performed during fusion for spondylolisthesis. Although radiographic appearance may improve, correlation with patient-reported outcomes (PROs) is rarely reported. In this study, the authors' aim was to assess the impact of spondylolisthesis reduction on 24-month PRO measures after decompression and fusion surgery for Meyerding grade I degenerative lumbar spondylolisthesis.

METHODS

The Quality Outcomes Database (QOD) was queried for patients undergoing posterior lumbar fusion for spondylolisthesis with a minimum 24-month follow-up, and quantitative correlation between Meyerding slippage reduction and PROs was performed. Baseline and 24-month PROs, including the Oswestry Disability Index (ODI), EQ-5D, Numeric Rating Scale (NRS)-back pain (NRS-BP), NRS-leg pain (NRS-LP), and satisfaction (North American Spine Society patient satisfaction questionnaire) scores were noted. Multivariable regression models were fitted for 24-month PROs and complications after adjusting for an array of preoperative and surgical variables. Data were analyzed for magnitude of slippage reduction and correlated with PROs. Patients were divided into two groups: < 3 mm reduction and ≥ 3 mm reduction.

RESULTS

Of 608 patients from 12 participating sites, 206 patients with complete data were identified in the QOD and included in this study. Baseline patient demographics, comorbidities, and clinical characteristics were similarly distributed between the cohorts except for depression, listhesis magnitude, and the proportion with dynamic listhesis (which were accounted for in the multivariable analysis). One hundred four (50.5%) patients underwent lumbar decompression and fusion with slippage reduction ≥ 3 mm (mean 5.19, range 3 to 11), and 102 (49.5%) patients underwent lumbar decompression and fusion with slippage reduction < 3 mm (mean 0.41, range 2 to -2). Patients in both groups (slippage reduction ≥ 3 mm, and slippage reduction < 3 mm) reported significant improvement in all primary patient reported outcomes (all p < 0.001). There was no significant difference with regard to the PROs between patients with or without intraoperative reduction of listhesis on univariate and multivariable analyses (ODI, EQ-5D, NRS-BP, NRS-LP, or satisfaction). There was no significant difference in complications between cohorts.

CONCLUSIONS

Significant improvement was found in terms of all PROs in patients undergoing decompression and fusion for lumbar spondylolisthesis. There was no correlation with clinical outcomes and magnitude of Meyerding slippage reduction.

Awake spinal surgery: simplifying the learning curve with a patient selection algorithm

OBJECTIVE

There is a learning curve for surgeons performing "awake" spinal surgery. No comprehensive guidelines have been proposed for the selection of ideal candidates for awake spinal fusion or decompression. The authors sought to formulate an algorithm to aid in patient selection for surgeons who are in the startup phase of awake spinal surgery.

METHODS

The authors developed an algorithm for selecting patients appropriate for awake spinal fusion or decompression using spinal anesthesia supplemented with mild sedation and local analgesia. The anesthetic protocol that was used has previously been reported in the literature. This algorithm was formulated based on a multidisciplinary team meeting and used in the first 15 patients who underwent awake lumbar surgery at a single institution.

RESULTS

A total of 15 patients who underwent decompression or lumbar fusion using the awake protocol were reviewed. The mean patient age was 61 ± 12 years, with a median BMI of 25.3 (IQR 2.7) and a mean Charlson Comorbidity Index of 2.1 ± 1.7; 7 patients (47%) were female. Key patient inclusion criteria were no history of anxiety, 1 to 2 levels of lumbar pathology, moderate stenosis and/or grade I spondylolisthesis, and no prior lumbar surgery at the level where the needle is introduced for anesthesia. Key exclusion criteria included severe and critical central canal stenosis or patients who did not meet the inclusion criteria. Using the novel algorithm, 14 patients (93%) successfully underwent awake spinal surgery without conversion to general anesthesia. One patient (7%) was converted to general anesthesia due to insufficient analgesia from spinal anesthesia. Overall, 93% (n = 14) of the patients were assessed as American Society of Anesthesiologists class II, with 1 patient (7%) as class III. The mean operative time was 115 minutes (± 60 minutes) with a mean estimated blood loss of 46 ± 39 mL. The median hospital length of stay was 1.3 days (IQR 0.1 days). No patients developed postoperative complications and only 1 patient (7%) required reoperation. The mean Oswestry Disability Index score decreased following operative intervention by 5.1 ± 10.8.

CONCLUSIONS

The authors propose an easy-to-use patient selection algorithm with the aim of assisting surgeons with patient selection for awake spinal surgery while considering BMI, patient anxiety, levels of surgery, and the extent of stenosis. The algorithm is specifically intended to assist surgeons who are in the learning curve of their first awake spinal surgery cases.

Smoking Is an Independent Risk Factor for 90-Day Readmission and Reoperation Following Posterior Cervical Decompression and Fusion

BACKGROUND

Posterior cervical decompression and fusion (PCF) is a common procedure used to treat various cervical spine pathologies, but the 90-d outcomes following PCF surgery continue to be incompletely defined.

OBJECTIVE

To identify risk factors associated with 90-d readmission and reoperation following PCF surgery.

METHODS

Adults undergoing PCF from 2012 to 2020 were identified. Demographic and radiographic data, surgical characteristics, and 90-d outcomes were collected. Univariate analysis was performed using Student's t-test, chi square, and Fisher exact tests as appropriate. Multivariable logistic regression models with lasso penalty were used to analyze various risk factors.

RESULTS

A total of 259 patients were included. The 90-d readmission and reoperation rates were 9.3% and 4.6%, respectively. The most common reason for readmission was surgical site infection (SSI) (33.3%) followed by new neurological deficits (16.7%). Patients who smoked tobacco had 3-fold greater odds of readmission compared to nonsmokers (odds ratio [OR]: 3.48; 95% CI 1.87-6.67; P = .0001). Likewise, the most common reason for reoperation was SSI (33.3%) followed by seroma and implant failure (25.0% each). Smoking was also an independent risk factor for reoperation, associated with nearly 4-fold greater odds of return to the operating room (OR: 3.53; 95% CI 1.53-8.57; P = .003).

CONCLUSION

Smoking is a significant predictor of 90-d readmission and reoperation in patients undergoing PCF surgery. Smoking cessation should be strongly considered preoperatively in elective PCF cases to minimize the risk of 90-d readmission and reoperation.

Anterior Cervical Discectomy With Fusion and Plating for Correction of Degenerative Cervical Kyphosis: 2-Dimensional Operative Video

This surgical video demonstrates the technique for correcting degenerative cervical kyphosis using an anterior cervical discectomy and fusion (ACDF). Degenerative cervical kyphosis can cause radiculopathy, myelopathy, and difficulty holding up one's head. The goal of surgical intervention is to alleviate pain, improve the ability for upright gaze, and decompress the spinal cord or nerve roots. Posterior-only approaches and anterior corpectomies are alternative treatments to address cervical kyphosis. However, an ACDF allows for sequential induction of lordosis via distraction over multiple segments and for further lordosis induction by sequential screw tightening, pulling the spine towards a lordotic cervical plate.1 This video shows 2 cases demonstrating a technique of correcting severe cervical degenerative kyphosis. The video illustrates our initial kyphotic Caspar pin placement coupled with sequential anterior distraction to correct kyphosis. The technique is most useful in patients who have good bone density, nonankylosed facets, and degenerative cervical kyphosis. We have received informed consent of this patient to submit this video.

POS1484-HPR THE ASSOCIATION OF STIGMA WITH DISEASE VARIABLES IN PATIENTS WITH FIBROMYALGIA (FM)

Background:

Stigma, defined as social devaluation of an individual, can be an important stressor for chronic pain patients [1]. Not every condition is stigmatized. A relevant factor for illness stigmatization seems to be whether the cause is mental-behavioural or physical. Chronic pain is often regarded as an imaginary illness or caused by psychological problems [2]. Sources of stigma for chronic pain patients are perceived negative attitudes from family members, the general public, and physicians [1]..

Objectives:

To assess perceived stigma and the associations with disease variables in a cohort of patients with FM.

Methods:

We invited 18 FM self-help groups in Germany to participate anonymously in our survey, and we sent the survey battery to 192 potential participants via postal mail. To measure perceived stigma, we used the Chronic Pain Stigma Scale (CPSS) developed by Reed [3], which has 30 items and 3 subscales (public, physicians, family). We also assessed sociodemographic characteristics, disease related variables (e.g., pain, stress, depression, anxiety), and other health-related factors, including health related quality of life [Healthy Days Core Module (CDC HDQOL-4)], disease specific impact (FIQ), fear avoidance belief questionnaire (physical activity subscale) (FABQ-PA), pain catastrophizing scale (PCS) and pain self-efficacy questionnaire (PSEQ).

Results:

In total 162 FM patients participated (=84% response rate). Their mean age was 58 years (SD=10), 84% (N=135) were female. Highest level of education was: Elementary School 29%, Junior High School 35%, High School 15%, College 12%, and other 10%. Duration of chronic pain was 18.2 years (SD=12.0). There was no significant gender difference in the stigma subscales, nor was there an association with duration of chronic pain. Table 1 presents the significant Pearson correlations.

Table 1.

Correlations of CPSS stigma subscales with health variables. *<.05; **<.01; ns=not significant.

CPSS-publicCPSS-physicianCPSS-familyRegional pain scalens.19*.20*VAS pain todaynsnsNsFIQ.20*.16*.22**HADS-anxiety.37*.20*.24*HADS-depression.41**.16*.25**CDC-HDQOL-4 General health.19*.18*.22** Physical health.19*nsns Mental health.20*ns.21* Impairment.24*nsnsPerceived stress scale.44**.24**.37**FABQ-PAns-.17*nsPCS.21*nsnsPSEQ.19*ns.18*

Conclusion:

Perceived stigma in our FM patient cohort has an important impact on a variety of different disease variables including mental and general health, physical functioning, and on pain coping. Stigmatizing attitudes perceived from the general public exhibited the greatest association with most variables in our chronic pain patients. Perceived stigma from physicians and the family were also related to negative disease consequences in our FM patients. To conclude, we assert that assessing and addressing multi-source perceived stigmatization in routine clinical care may improve the management and wellbeing of patients with FM.

References:

[1]Waugh OC, Byrne DG, Nicholas MK. Internalized stigma in people living with chronic pain. J Pain 2014;15(5):550 e1-10.

[2]Werner A, Isaksen LW, Malterud K. ‘I am not the kind of woman who complains of everything’: illness stories on self and shame in women with chronic pain. Soc Sci Med 2004;59(5): 1035-45

[3]Reed P. Chronic pain stigma: developement of the Chronic Pain Stigma Scale. 2005.

Disclosure of Interests:

None declared

AB0185 ULTRASOUND IN INFLAMMATORY ARTHRALGIA: SHOULD WE ALWAYS SCAN?

Background:

Patients with inflammatory arthralgia (IA) are considered to be at increased risk for progression to RA. Ultrasound (US) has shown high sensitivity to detect synovitis compared with physical examination. Thus, US is recommended to identify subclinical synovitis in patients without clinical signs of inflammation.

Objectives:

To determine the frequency and pattern of US detected active inflammation in patients with IA and investigate factors contributing to predict this outcome.

Methods:

An US clinic is scheduled in an academic center running twice every week. A retrospective analysis of our US unit cohort during a period of 12 months was undertaken. Patients with IA and no previous diagnosis of inflammatory arthropathies were included for analysis. Inclusion criteria of IA definition included: severe symptoms presenting in the morning, duration of morning stiffness ≥60 min, symptoms predominantly located in MCP joints and absence of clinically detected synovitis by the referral rheumatologist. The following routinely collected variables were included in the analysis: demographics, clinical features and laboratory tests. Patients underwent bilateral US examination of hands and/or feet according to the European League Against Rheumatism (EULAR) guidelines. The presence of synovitis and tenosynovitis was assessed on a semi quantitative scale (0–3) for Grey Scale(GS)/Power Doppler(PD). Active inflammation was defined as PD synovitis and/or tenosynovitis >1 at any location. First, differences between groups were tested using chi-squared/Fisher and Student-t tests in the univariate analysis. Second, multivariate logistic regression models were employed to investigate the association between possible predictive factors of US active inflammation.

Results:

A total of 110 patients were included in the analysis. Mean age was 53.6±15.6 years, 80 (72.7%) were females, and mean symptoms duration was 11.7±9.9 months (Table1). A total of 76 (69.1%) patients presented with a polyarticular arthralgia pattern. US active inflammation were present in 38 (34.5%) patients (28.2% showed PD synovitis and 19.1% PD tenosynovitis). Hands were most commonly involved with PD synovitis at wrists in 18.2% and at MCP in 14.5% of patients. For PD tenosynovitis, the flexor MCP 2-5 (4.5%) and 6th extensor tenosynovitis (5.5 %) were the most frequent affected locations. Only 9 (8.2%) patients had erosions in hands and/or feet at baseline examination. In the univariate analysis, the higher ESR values, the shorter time from symptoms onset and the presence of ACPA were significantly associated with the presence of US active inflammation (p<0.001, p=0.035 and p=0.01, respectively). In the multivariate analysis, only ACPA and ESR values (OR=1,0003; 95%CI 1,000-1,006 and OR=1.054; 95%CI 1.016-1.094), remained significantly associated with the detection of US active inflammation.

Conclusion:

US features of active inflammation are found in 1 over 3 patients with IA being PD synovitis the most common finding, specially at the wrists and MCP joints. Higher ESR and ACPA values are significantly associated with the presence of US active inflammation. Thus, we strongly recommend the use of PD US to detect subclinical inflammation in at-risk patients with IA with no sign of inflammation on clinical examination, especially those with high ESR and ACPA values.

Table 1.

Baseline characteristics of patients with IA

Totaln= 110US inflammatoryfindingsn= 38 (34.5%)Non-US inflammatoryfindingsn=72 (65.5%)pAge53.6 ± 15.657.2±16.251.6±13.40.071SexFemale80 (72.7%)26 (68.4%)54 (75%)0.461Smokingn= 87Non smoker45 (51.7%)12 (44.4%)33 (55%)0.412Smoker34 (39.1%)11 (40.7%)23 (38.3%)Former smoker8 (9.2%)4 (14.8%)4 (6.7%)ExtensionMonoarticular12 (10.9%)6 (15.8%)6 (8.3%)0.176Oligoarticular 22 (20%)10 (26.3%)12 (16.7%)Polyarticular76 (69.1%)22 (57.9%) 54 (75%)Time (months)from symptoms onset11.7 ± 9.99.1±8.113±10.50.035ESR (mm/h) n=4524.7 ± 18.233.1±21.820.3 ±14.4<0.001RF (IU/mL) n=5339.1 ± 230.528.5±5645.1±286.10.647ACPA (IU/mL) n=5698.1 ± 331.2209.4±488.426±125.20.01

Disclosure of Interests:

None declared

AB0889-HPR PERCEIVED SATISFACTION WITH CHRONIC PAIN CARE IN GERMAN PATIENTS WITH FIBROMYALGIA (FM)

Background:

In chronic pain care a multidimensional perspective with attention to patients’ cognitions, emotions, and their ability to cope is needed (1). Previous studies are also pointing to the role of experiencing meaningfulness in life in the adjustment to disability.Therefore care should additionally focus on the existential domain of patients’ lives to live up to a holistic care approach (2). However, there are only a few studies on how FM patients are satisfied with practitioners’ attention to multiple aspects of life with a chronic pain condition.

Objectives:

To assess perceived satisfaction with chronic pain care and its associations with health variables in a cohort of patients with FM.

Methods:

We invited 18 FM self-help groups in Germany to participate anonymously in our survey and sent them in total 192 paper-and-pencil surveys. Sociodemographics, disease related variables (e.g. pain, general health) and psychological variables [e.g. depression, anxiety, hope, stress] were assessed with standardized instruments, including 5 items (answer format 1=very unsatisfied – 10=very satisfied) assessing subjective satisfaction with medical care in different domains with the following questions: How satisfied are you with the attention of your treatment team/physician at home for physiological aspects of your pain (Physio)/ the consequences of the pain on your physical functioning (Physical)/ on your psychological well-being (Mental)/ on your social life (Social)/ on your meaning in life (Meaning).

Results:

In total 162 FM patients participated (=84% response rate). Their mean age was 58 years (SD=10), 84% (N=135) were female. Highest level of education was: Elementary School 29%, Junior High School 35%, High School 15%, College 12%, and other 10%. Duration of chronic pain was 18.2 years (SD=12.0). The satisfaction with care scale showed good internal consistency and measured one factor. The means of the subscale were: Physio 5.7 (SD=2.5)/ Physical 5.5 (SD=2.5)/ Mental 5.5 (SD=2.6)/ Social 5.0 (SD=2.5)/ Meaning 5.3 (SD=2.6). Correlations of the subscales are depicted in Table 1. There were no associations between pain variables and satisfaction with care, but satisfaction with care was associated with mental health, but not physical health, outcomes.

Table 1.

Correlations of satisfaction of care with different health variables. Subscales physiological and physical aspects and HADS-anxiety were not significantly correlated. *<.05; **<.01; ns=not significant.

PhysioPhysicalMentalSocialMeaningHADS-depression-.10 (ns)-.12 (ns)-.19*-.16*-.14 (ns)General Health .02 (ns) .14 (ns) .13 (ns) .18* .12 (ns)Stress-.15 (ns)-.14 (ns)-.17*-.17*-.13 (ns)Hope .18 (ns) .18 (ns) .26** .26* .22*

Conclusion:

In this cohort of German FM patients the average satisfaction with care overall, as well as the specific aspects of care, was only moderate. Interestingly we found associations between satisfaction with care in mental, social and meaning in life aspects with psychological well-being pointing to the fact that care for chronic pain patients should also include those aspects in addition to just addressing biomedical aspects.

References:

[1]Flor H and Turk D. Chronic pain: an integrated approach. Seattle, WA: IASP Press, 2011.

[2]Dezutter J, Casalin S, Wacholtz A, et al. Meaning in life: An important factor for the psychological well-being of chronically ill patients? Rehabilitat Psychol 2013; 58:334–341.

Disclosure of Interests:

None declared

Posterior Displacement of L1 May be a Risk Factor for Proximal Junctional Kyphosis After Adult Spinal Deformity Correction

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

Overcorrection in adult spinal deformity (ASD) surgery may lead to proximal junctional kyphosis (PJK) because of posterior spinal displacement. The aim of this paper is to determine if the L1 position relative to the gravity line (GL) is associated with PJK.

METHODS

ASD patients fused from the lower thoracic spine to sacrum by 4 spine surgeons at our hospital were retrospectively studied. Lumbar-only and upper thoracic spine fusions were excluded. Spinopelvic parameters, the L1 plumb line (L1PL), L1 distance to the GL (L1-GL), and Roussouly type were measured.

RESULTS

One hundred fourteen patients met inclusion criteria (63 patients with PJK, 51 without). Mean age and follow up was 65.51 and 3.39 years, respectively. There was no difference between the PJK and the non-PJK groups in baseline demographics, pre-operative and immediate post-operative pelvic incidence-lumbar lordosis mismatch, sagittal vertical axis, or coronal Cobb. The immediate postoperative L1-GL was -7.24 cm in PJK and -3.45 cm in non-PJK (P < 0.001), L1PL was 1.71 cm in PJK and 3.07 cm in non-PJK (P = 0.004), and PT (23.76° vs 18.90°, P = 0.026) and TK (40.56° vs 31.39°, P < 0.001) were larger in PJK than in non-PJK. After univariate and multivariate analyses, immediate postoperative TK and immediate postoperative L1-GL were independent risk factors for PJK without collinearity.

CONCLUSIONS

A dorsally displaced L1 relative to the GL was associated with an increased risk of PJK after ASD surgery. The postoperative L1-GL distance may be a factor to consider during ASD surgery.

An analysis of tumor-related potential spinal column instability (Spine Instability Neoplastic Scores 7-12) eventually requiring surgery with a 1-year follow-up

OBJECTIVE

Within the Spine Instability Neoplastic Score (SINS) classification, tumor-related potential spinal instability (SINS 7-12) may not have a clear treatment approach. The authors aimed to examine the proportion of patients in this indeterminate zone who later required surgical stabilization after initial nonoperative management. By studying this patient population, they sought to determine if a clear SINS cutoff existed whereby the spine is potentially unstable due to a lesion and would be more likely to require stabilization.

METHODS

Records from patients treated at the University of California, San Francisco, for metastatic spine disease from 2005 to 2019 were retrospectively reviewed. Seventy-five patients with tumor-related potential spinal instability (SINS 7-12) who were initially treated nonoperatively were included. All patients had at least a 1-year follow-up with complete medical records. A univariate chi-square test and Student t-test were used to compare categorical and continuous outcomes, respectively, between patients who ultimately underwent surgery and those who did not. A backward likelihood multivariate binary logistic regression model was used to investigate the relationship between clinical characteristics and surgical intervention. Recursive partitioning analysis (RPA) and single-variable logistic regression were performed as a function of SINS.

RESULTS

Seventy-five patients with a total of 292 spinal metastatic sites were included in this study; 26 (34.7%) patients underwent surgical intervention, and 49 (65.3%) did not. There was no difference in age, sex, comorbidities, or lesion location between the groups. However, there were more patients with a SINS of 12 in the surgery group (55.2%) than in the no surgery group (44.8%) (p = 0.003). On multivariate analysis, SINS > 11 (OR 8.09, CI 1.96-33.4, p = 0.004) and Karnofsky Performance Scale (KPS) score < 60 (OR 0.94, CI 0.89-0.98, p = 0.008) were associated with an increased risk of surgery. KPS score was not correlated with SINS (p = 0.4). RPA by each spinal lesion identified an optimal cutoff value of SINS > 10, which were associated with an increased risk of surgical intervention. Patients with a surgical intervention had a higher incidence of complications on multivariable analysis (OR 2.96, CI 1.01-8.71, p = 0.048).

CONCLUSIONS

Patients with a mean SINS of 11 or greater may be at increased risk of mechanical instability requiring surgery after initial nonoperative management. RPA showed that patients with a KPS score of 60 or lower and a SINS of greater than 10 had increased surgery rates.

The minimally invasive interbody selection algorithm for spinal deformity

OBJECTIVE

Minimally invasive surgery (MIS) for spinal deformity uses interbody techniques for correction, indirect decompression, and arthrodesis. Selection criteria for choosing a particular interbody approach are lacking. The authors created the minimally invasive interbody selection algorithm (MIISA) to provide a framework for rational decision-making in MIS for deformity.

METHODS

A retrospective data set of circumferential MIS (cMIS) for adult spinal deformity (ASD) collected over a 5-year period was analyzed by level in the lumbar spine to identify surgeon preferences and evaluate segmental lordosis outcomes. These data were used to inform a Delphi session of minimally invasive deformity surgeons from which the algorithm was created. The algorithm leads to 1 of 4 interbody approaches: anterior lumbar interbody fusion (ALIF), anterior column release (ACR), lateral lumbar interbody fusion (LLIF), and transforaminal lumbar interbody fusion (TLIF). Preoperative and 2-year postoperative radiographic parameters and clinical outcomes were compared.

RESULTS

Eleven surgeons completed 100 cMISs for ASD with 338 interbody devices, with a minimum 2-year follow-up. The type of interbody approach used at each level from L1 to S1 was recorded. The MIISA was then created with substantial agreement. The surgeons generally preferred LLIF for L1-2 (91.7%), L2-3 (85.2%), and L3-4 (80.7%). ACR was most commonly performed at L3-4 (8.4%) and L2-3 (6.2%). At L4-5, LLIF (69.5%), TLIF (15.9%), and ALIF (9.8%) were most commonly utilized. TLIF and ALIF were the most selected approaches at L5-S1 (61.4% and 38.6%, respectively). Segmental lordosis at each level varied based on the approach, with greater increases reported using ALIF, especially at L4-5 (9.2°) and L5-S1 (5.3°). A substantial increase in lordosis was achieved with ACR at L2-3 (10.9°) and L3-4 (10.4°). Lateral interbody arthrodesis without the use of an ACR did not generally result in significant lordosis restoration. There were statistically significant improvements in lumbar lordosis (LL), pelvic incidence-LL mismatch, coronal Cobb angle, and Oswestry Disability Index at the 2-year follow-up.

CONCLUSIONS

The use of the MIISA provides consistent guidance for surgeons who plan to perform MIS for deformity. For L1-4, the surgeons preferred lateral approaches to TLIF and reserved ACR for patients who needed the greatest increase in segmental lordosis. For L4-5, the surgeons' order of preference was LLIF, TLIF, and ALIF, but TLIF failed to demonstrate any significant lordosis restoration. At L5-S1, the surgical team typically preferred an ALIF when segmental lordosis was desired and preferred a TLIF if preoperative segmental lordosis was adequate.

Long-term radiographic outcomes of expandable versus static cages in transforaminal lumbar interbody fusion

OBJECTIVE

Potential advantages of using expandable versus static cages during transforaminal lumbar interbody fusion (TLIF) are not fully established. The authors aimed to compare the long-term radiographic outcomes of expandable versus static TLIF cages.

METHODS

A retrospective review of 1- and 2-level TLIFs over a 10-year period with expandable and static cages was performed at the University of California, San Francisco. Patients with posterior column osteotomy (PCO) were subdivided. Fusion assessment, cage subsidence, anterior and posterior disc height, foraminal dimensions, pelvic incidence (PI), segmental lordosis (SL), lumbar lordosis (LL), pelvic incidence-lumbar lordosis mismatch (PI-LL), pelvic tilt (PT), sacral slope (SS), and sagittal vertical axis (SVA) were assessed.

RESULTS

A consecutive series of 178 patients (with a total of 210 levels) who underwent TLIF using either static (148 levels) or expandable cages (62 levels) was reviewed. The mean patient age was 60.3 ± 11.5 years and 62.8 ± 14.1 years for the static and expandable cage groups, respectively. The mean follow-up was 42.9 ± 29.4 months for the static cage group and 27.6 ± 14.1 months for the expandable cage group. Within the 1-level TLIF group, the SL and PI-LL improved with statistical significance regardless of whether PCO was performed; however, the static group with PCOs also had statistically significant improvement in LL and SVA. The expandable cage with PCO subgroup had significant improvement in SL only. All of the foraminal parameters improved with statistical significance, regardless of the type of cages used; however, the expandable cage group had greater improvement in disc height restoration. The incidence of cage subsidence was higher in the expandable group (19.7% vs 5.4%, p = 0.0017). Within the expandable group, the unilateral facetectomy-only subgroup had a 5.6 times higher subsidence rate than the PCO subgroup (26.8% vs 4.8%, p = 0.04). Four expandable cages collapsed over time.

CONCLUSIONS

Expandable TLIF cages may initially restore disc height better than static cages, but they also have higher rates of subsidence. Unilateral facetectomy alone may result in more subsidence with expandable cages than using bilateral PCO, potentially because of insufficient facet release. Although expandable cages may have more power to induce lordosis and restore disc height than static cages, subsidence and endplate violation may negate any significant gains compared to static cages.

Clinical and Radiographic Outcomes After Minimally Invasive Transforaminal Lumbar Interbody Fusion-Early Experience Using a Biplanar Expandable Cage for Lumbar Spondylolisthesis

BACKGROUND

Minimally invasive transforaminal lumbar interbody fusion (MIS TLIF) is a surgical technique frequently used to treat symptomatic lumbar spondylolisthesis. We aim to investigate the safety and efficacy of using a biplanar expandable cage in the treatment of symptomatic lumbar spondylolisthesis using a MIS TLIF approach.

METHODS

A retrospective review of patient records was performed on patients who underwent MIS TLIF for symptomatic lumbar spondylolisthesis using the FlareHawk cage over a 12-month period. Patient demographics, as well as preoperative and postoperative clinical and radiographic outcome measures were recorded and analyzed.

RESULTS

A total of 13 consecutive patients underwent MIS TLIF for symptomatic spondylolisthesis during the study period. The mean age was 60.2 ± 13.9 years, and 61.5% were female. The mean preoperative and postoperative slippage was 7.0 ± 3.0 mm and 1.0 ± 1.9 mm, respectively. The preoperative mean segmental lordosis was 5.1° ± 6.0°, mean anterior, posterior disc, and foraminal height were 9.1 ± 3.9 mm, 5.7 ± 1.5 mm, and 11.0 ± 2.0 mm, respectively. The postoperative mean segmental lordosis was 6.8° ± 4.7°, and mean anterior, posterior disc, and foraminal height were 11.4 ± 2.2 mm, 7.8 ± 1.0 mm, and 12.3 ± 1.3 mm. There was improvement in all radiographic parameters postoperatively. The mean Visual Analog Scale (VAS) back pain, VAS leg pain improved from 7.0 ± 2.9 and 5.1 ± 3.0 preoperatively to 3.1 ± 2.9 and 1.1 ± 1.7 at the latest clinic follow-up visit, respectively (P = .0081). The mean EuroQol-Five Dimensions (EQ5D) score improved from 0.37 ± 1.7 to 0.66 ± 0.23 after surgery. There was no subsidence, endplate violation, cage migration, or other implant-related complications. No patient required reoperation.

CONCLUSIONS

The biplanar expandable cage is both safe and efficacious in treating symptomatic lumbar spondylolisthesis using the MIS TLIF approach. Spine surgeons should be familiar with the biplanar expandable cage technology and keep it in their armamentarium in surgical treatment of lumbar spondylolisthesis.

LEVEL OF EVIDENCE

4.

Is the Goutallier grade of multifidus fat infiltration associated with adjacent-segment degeneration after lumbar spinal fusion?

OBJECTIVE

The aim of this study was to investigate whether fat infiltration of the lumbar multifidus (LM) muscle affects revision surgery rates for adjacent-segment degeneration (ASD) after L4-5 transforaminal lumbar interbody fusion (TLIF) for degenerative spondylolisthesis.

METHODS

A total of 178 patients undergoing single-level L4-5 TLIF for spondylolisthesis (2006 to 2016) were retrospectively analyzed. Inclusion criteria were a minimum 2-year follow-up, preoperative MR images and radiographs, and single-level L4-5 TLIF for degenerative spondylolisthesis. Twenty-three patients underwent revision surgery for ASD during the follow-up. Another 23 patients without ASD were matched with the patients with ASD. Demographic data, Roussouly curvature type, and spinopelvic parameter data were collected. The fat infiltration of the LM muscle (L3, L4, and L5) was evaluated on preoperative MRI using the Goutallier classification system.

RESULTS

A total of 46 patients were evaluated. There were no differences in age, sex, BMI, or spinopelvic parameters with regard to patients with and those without ASD (p > 0.05). Fat infiltration of the LM was significantly greater in the patients with ASD than in those without ASD (p = 0.029). Fat infiltration was most significant at L3 in patients with ASD than in patients without ASD (p = 0.017). At L4 and L5, there was an increasing trend of fat infiltration in the patients with ASD than in those without ASD, but the difference was not statistically significant (p = 0.354 for L4 and p = 0.077 for L5).

CONCLUSIONS

Fat infiltration of the LM may be associated with ASD after L4-5 TLIF for spondylolisthesis. Fat infiltration at L3 may also be associated with ASD at L3-4 after L4-5 TLIF.

Preparation and in vitro evaluation of PLA/biphasic calcium phosphate filaments used for fused deposition modelling of scaffolds

Ceramic materials such as calcium phosphates (CaPs) with a composition similar to the mineral phase of bones and polymeric polylactic acid (PLA) are potential candidates for the manufacturing of scaffolds to act as bone substitutes and for tissue engineering applications, due to their bioresorbability and biocompatibility. Variables such as porosity, topography, morphology, and mechanical properties play an essential role in the scaffolds response. In this paper, a polymer/ceramic composite filament of 1.7 mm in diameter based on PLA and biphasic calcium phosphates (BCPs) was obtained by hot-melt extrusion in a single screw extruder. The particles of BCP were obtained by solution-combustion synthesis, and the PLA used was commercial grade. The BCPs ceramics were characterized by X-ray diffraction (XRD), scanning electron microscopic (SEM), transmission electron microscopy (TEM), and Brunauer, Emmett, and Teller (BET). It was possible to confirm that the main inorganic phases were hydroxyapatite (HAP) and tricalcium phosphate (TCP) with grain sizes below 100 nm and with high porosity. The Filaments obtained are a bit fragile but were able to be used in fused deposition modelling (FDM) using low-cost commercial printers. The filaments were characterized by SEM and energy dispersive X-ray (EDX). The in-vitro tests of filaments showed deposition of apatite phases on their surface, non-cytotoxic behavior, adequate cell proliferation and cell adhesion.

Genotype-Phenotype Correlation of Tracheal Cartilaginous Sleeves and Fgfr2 Mutations in Mice

OBJECTIVES

To characterize tracheal cartilage morphology in mouse models of fibroblast growth factor receptor (Fgfr2)-related craniosynostosis syndromes. To establish relationships between specific Fgfr2 mutations and tracheal cartilaginous sleeve (TCS) phenotypes in these mouse models.

METHODS

Postnatal day 0 knock-in mouse lines with disease-specific genetic variations in the Fgfr2 gene (Fgfr2^C342Y/C342Y , Fgfr2^C342Y/+ , Fgfr2^+/Y394C , Fgfr2^+/S252W , and Fgfr2^+/P253R ) as well as line-specific controls were utilized. Tracheal cartilage morphology as measured by gross analyses, microcomputed tomography (μCT), and histopathology were compared using Chi-squared and single-factor analysis of variance statistical tests.

RESULTS

A greater proportion of rings per trachea were abnormal in Fgfr2^C342Y/+ tracheas (63%) than Fgfr2^+/S252W (17%), Fgfr2^+/P253R (17%), Fgfr2^+/Y394C (12%), and controls (10%) (P < .001 for each vs. Fgfr2^C342Y/+ ). TCS segments were found only in Fgfr2^C342Y/C342Y (100%) and Fgfr2^C342Y/+ (72%) tracheas. Cricoid and first-tracheal ring fusion was noted in all Fgfr2^C342Y/C342Y and 94% of Fgfr2^C342Y/+ samples. The Fgfr2^C342Y/C342Y and Fgfr2^C342Y/+ groups were found to have greater areas and volumes of cartilage than other lines on gross analysis and μCT. Histologic analyses confirmed TCS among the Fgfr2^C342Y/C342Y and Fgfr2^C342Y/+ groups, without appreciable differences in cartilage morphology, cell size, or density; no histologic differences were observed among other Fgfr2 lines compared to controls.

CONCLUSION

This study found TCS phenotypes only in the Fgfr2^C342Y mouse lines. These lines also had increased tracheal cartilage compared to other mutant lines and controls. These data support further study of the Fgfr2 mouse lines and the investigation of other Fgfr2 variants to better understand their role in tracheal development and TCS formation.

LEVEL OF EVIDENCE

NA Laryngoscope, 131:E1349-E1356, 2021.

A-09 The Relationship Between Subjective Cognitive Complaints, Depression, and Executive Functioning in mTBI Veterans

Objective

Among individuals with mild traumatic brain injury (mTBI), those with depression report greater subjective cognitive complaints than those without depression. In mTBI patients with general cognitive complaints, depression may account for poor performance on objective neuropsychological measures. This study seeks to expand this research by examining depression, subjective executive functioning (EF) complaints, and objective EF performance in Veterans with mTBI.

Method

Fifty-seven Veterans with deployment-related mTBI (12% female; age M = 42.0, SD = 13.6; years education M = 15.0, SD = 1.8) with (n = 29) or without (n = 28) a chart diagnosis of depression. Participants were administered the Behavioral Rating Inventory of Executive Functioning (BRIEF) and objective neuropsychological measures of working memory (i.e., Weschler Adult Intelligence Scale-IV Working Memory Index) and aspects of EF (i.e., Trail Making Test B and Delis-Kaplan Executive Functioning System (D-KEFS) subtests).

Results

Principal component analysis identified similar domains of EF to the BRIEF, including: task monitoring (Trail Making Test B, D-KEFS Letter Fluency, and D-KEFS Tower Test, eigenvalue = 1.93) and shifting (D-KEFS: Color-Word Interference Conditions 3 and 4, and Category Switching, eigenvalue = 1.24). Individuals with depression had greater subjective EF complaints in each BRIEF domain than non-depressed individuals (p’s ≤ .01). However, subjective complaints in these domains were not related to objective performance (r’s = −0.17,-0.19, p’s &gt; .05). Moreover, depressed and non-depressed individuals performed similarly on all EF measures (p’s &gt; .05).

Conclusions

mTBI Veterans with depression report more subjective EF complaints than those without depression. The lack of association between subjective complaints and objective EF performance suggests it is important to treat depression in mTBI patients to remedy perceived cognitive deficits.

The association between lower Hounsfield units of the upper instrumented vertebra and proximal junctional kyphosis in adult spinal deformity surgery with a minimum 2-year follow-up

OBJECTIVE

Patients undergoing long-segment fusions from the lower thoracic (LT) spine to the sacrum for adult spinal deformity (ASD) correction are at risk for proximal junctional kyphosis (PJK). One mechanism of PJK is fracture of the upper instrumented vertebra (UIV) or higher (UIV+1), which may be related to bone mineral density (BMD). Because Hounsfield units (HUs) on CT correlate with BMD, the authors evaluated whether HU values were correlated with PJK after long fusions for ASD.

METHODS

The authors performed a retrospective study of patients older than 50 years who had undergone ASD correction from the LT spine to the sacrum in the period from October 2007 to January 2018 and had a minimum 2-year follow-up. Demographic and spinopelvic parameters were measured. HU values were measured on preoperative CT at the UIV, UIV+1, and UIV+2 (2 levels above the UIV) levels and were assessed for correlations with PJK.

RESULTS

The records of 127 patients were reviewed. Fifty-four patients (19 males and 35 females) with a mean age of 64.91 years and mean follow-up of 3.19 years met the study inclusion criteria; there were 29 patients with PJK and 25 patients without. There was no statistically significant difference in demographics or follow-up between these two groups. Neither was there a difference between the groups with regard to postoperative pelvic incidence (PI), sacral slope (SS), lumbar lordosis (LL), PI minus LL (PI-LL), thoracic kyphosis (TK), or sagittal vertical axis (SVA; all p > 0.05). Postoperative pelvic tilt (p = 0.003) and T1 pelvic angle (p = 0.014) were significantly higher in patients with PJK than in those without. Preoperative HUs at UIV, UIV+1, and UIV+2 were 120.41, 124.52, and 129.28 in the patients with PJK, respectively, and 152.80, 155.96, and 160.00 in the patients without PJK, respectively (p = 0.011, 0.02, and 0.018). Three receiver operating characteristic (ROC) curves for preoperative HU values at the UIV, UIV+1, and UIV+2 as a predictor for PJK were established, with areas under the ROC curve of 0.710 (95% CI 0.574–0.847), 0.679 (95% CI 0.536–0.821), and 0.681 (95% CI 0.539–0.824), respectively. The optimal HU value by Youden index was 104 HU at the UIV (sensitivity 0.840, specificity 0.517), 113 HU at the UIV+1 (sensitivity 0.720, specificity 0.517), and 110 HU at the UIV+2 (sensitivity 0.880, specificity 0.448).

CONCLUSIONS

In patients undergoing long-segment fusions from the LT spine to the sacrum for ASD, PJK was associated with lower HU values on CT at the UIV, UIV+1, and UIV+2. The measurement of HU values on preoperative CTs may be a useful adjunct for ASD surgery planning.

Integrated Transcriptome and Network Analysis Reveals Spatiotemporal Dynamics of Calvarial Suturogenesis

Craniofacial abnormalities often involve sutures, the growth centers of the skull. To characterize the organization and processes governing their development, we profile the murine frontal suture, a model for sutural growth and fusion, at the tissue- and single-cell level on embryonic days (E)16.5 and E18.5. For the wild-type suture, bulk RNA sequencing (RNA-seq) analysis identifies mesenchyme-, osteogenic front-, and stage-enriched genes and biological processes, as well as alternative splicing events modifying the extracellular matrix. Single-cell RNA-seq analysis distinguishes multiple subpopulations, of which five define a mesenchyme-osteoblast differentiation trajectory and show variation along the anteroposterior axis. Similar analyses of in vivo mouse models of impaired frontal suturogenesis in Saethre-Chotzen and Apert syndromes, Twist1+/- and Fgfr2+/S252W, demonstrate distinct transcriptional changes involving angiogenesis and ribogenesis, respectively. Co-expression network analysis reveals gene expression modules from which we validate key driver genes regulating osteoblast differentiation. Our study provides a global approach to gain insights into suturogenesis.

Crossing the Cervicothoracic Junction During Posterior Cervical Fusion for Myelopathy Is Associated With Superior Radiographic Parameters But Similar Clinical Outcomes

Background

For laminectomy and posterior spinal fusion (LPSF) surgery for cervical spondylotic myelopathy (CSM), the evidence is unclear as to whether fusions should cross the cervicothoracic junction (CTJ).

Objective

To compare LPSF outcomes between those with and without lower instrumented vertebrae (LIV) crossing the CTJ.

Methods

A consecutive series of adults undergoing LPSF for CSM from 2012 to 2018 with a minimum of 12-mo follow-up were identified. LPSF with subaxial upper instrumented vertebrae and LIV between C6 and T2 were included. Clinical and radiographic outcomes were compared.

Results

A total of 79 patients were included: 46 crossed the CTJ (crossed-CTJ) and 33 did not. The mean follow-up was 22.2 mo (minimum: 12 mo). Crossed-CTJ had higher preoperative C2-7 sagittal vertical axis (cSVA) (33.3 ± 16.0 vs 23.8 ± 12.4 mm, P = .01) but similar preoperative cervical lordosis (CL) and CL minus T1-slope (CL minus T1-slope) (P &gt; .05, both comparisons). The overall reoperation rate was 3.8% (crossed-CTJ: 2.2% vs not-crossed: 6.1%, P = .37). In adjusted analyses, crossed-CTJ was associated with superior cSVA (β = –9.7; P = .002), CL (β = 6.2; P = .04), and CL minus T1-slope (β = –6.6; P = .04), but longer operative times (β = 46.3; P = .001). Crossed- and not-crossed CTJ achieved similar postoperative patient-reported outcomes [Visual Analog Scale (VAS) neck pain, VAS arm pain, Nurick Grade, Modified Japanese Orthopedic Association Scale, Neck Disability Index, and EuroQol-5D] in adjusted multivariable analyses (adjusted P &gt; .05). For the entire cohort, higher postoperative CL was associated with lower postoperative arm pain (adjusted Pearson's r –0.1, P = .02). No postoperative cervical radiographic parameters were associated with neck pain (P &gt; .05).

Conclusion

Subaxial LPSF for CSM that crossed the CTJ were associated with superior radiographic outcomes for cSVA, CL, and CL minus T1-slope, but longer operative times. There were no differences in neck pain or reoperation rate.

Lower Hounsfield units on CT are associated with cage subsidence after anterior cervical discectomy and fusion

OBJECTIVE

A consequence of anterior cervical discectomy and fusion (ACDF) is graft subsidence, potentially leading to kyphosis, nonunion, foraminal stenosis, and recurrent pain. Bone density, as measured in Hounsfield units (HUs) on CT, may be associated with subsidence. The authors evaluated the association between HUs and subsidence rates after ACDF.

METHODS

A retrospective study of patients treated with single-level ACDF at the University of California, San Francisco, from 2008 to 2017 was performed. HU values were measured according to previously published methods. Only patients with preoperative CT, minimum 1-year follow-up, and single-level ACDF were included. Patients with posterior surgery, tumor, infection, trauma, deformity, or osteoporosis treatment were excluded. Changes in segmental height were measured at 1-year follow-up compared with immediate postoperative radiographs. Subsidence was defined as segmental height loss of more than 2 mm.

RESULTS

A total of 91 patients met inclusion criteria. There was no significant difference in age or sex between the subsidence and nonsubsidence groups. Mean HU values in the subsidence group (320.8 ± 23.9, n = 8) were significantly lower than those of the nonsubsidence group (389.1 ± 53.7, n = 83, p < 0.01, t-test). There was a negative correlation between the HU values and segmental height loss (Pearson's coefficient -0.735, p = 0.01). Using receiver operating characteristic curves, the area under the curve was 0.89, and the most appropriate threshold of HU value was 343.7 (sensitivity 77.1%, specificity 87.5%). A preoperative lower HU is a risk factor for postoperative subsidence (binary logistic regression, p < 0.05). The subsidence rate and distance between allograft and polyetheretherketone (PEEK) materials were not significantly different (PEEK 0.9 ± 0.7 mm, allograft 1.0 ± 0.7 mm; p > 0.05).

CONCLUSIONS

Lower preoperative CT HU values are associated with cage subsidence in single-level ACDF. Preoperative measurement of HUs may be useful in predicting outcomes after ACDF.

THU0445 PREVALENCE AND INFLUENCE OF DISEASE DURATION IN THE AMOUNT OF ARTICULAR AND PERIARTICULAR DEPOSITS OF MONOSODIUM URATE (MSU) CRYSTALS IN NON-TREATED GOUTY ARTHRITIS PATIENTS

Background:

Monosodium urate crystals deposition arthritis (Gout) is the most prevalent inflammatory arthropathy in our society. The use of muskuloskeletal ultrasound (MSUS) is emerging as a diagnostic method of patients with gout, mainly in the past few years.

Objectives:

Our objective is to establish the prevalence of articular and periarticular ultrasound lesions in patients with known or recent gout diagnosis without urate-lowering therapy (ULT) as well as to analyze the influence of disease duration on these findings.

Methods:

Observational, cross-sectional and descriptive study, including patients with diagnosis of Gout (fulfilling the ACR / EULAR Classification Criteria 2015) between September and November 2019 in our Rheumatology service of a tertiary center. Demographic and clinical records were collected (table 1) and MSUS was performed on each patient systematically by two rheumatologists, exploring a total of 20 structures (8 tendons and 12 joints). Suggestive images of MSU crystals deposition were defined following the OMERACT 2015 ultrasound elementary lesions definitions. Deposits included lesions as tophus, hyperechoic aggregates (HA) and double contour (DC).

Table 1.

Demographic and laboratory data

FeaturesPatients (n=38)%SexMen 34 Women 489,5 10,5Age (years)Mean ±SD 60±14,43ComorbiditiesArterial hypertension18 Mellitus diabetes 4 Dyslipidemia 13 Smoking 7 Alcohol 1447,4 10,5 34,2 18,4 36,8BMI (Kg/m2)Mean±SD 27,3±4,23Blood urate levels (mg/dL)Mean±SD 8,2±1,74Blood creatinine levels (mg/dL)Mean±SD 1,09±0,75

Results:

A total of 38 patients were included, 34 men (89.5%) and 4 women (10.5). Twenty seven (71.1%) presented MSU crystals in synovial fluid samples, while rest of them (28.9%) met 2015 ACR / EULAR Clasiffication Criteria for Gout. Disease duration (since onset of symptoms) was less than 6 months in 20 patients (52.6%) and longer than 6 months in 18 (47.36%). Thirty seven patients (97.36%) presented some type of MSU deposits on the explored areas. One hundred and thirty (17,10%), out of 760 explored locations, had MSU deposits. Patients with disease duration less than 6 months had 56 locations with deposits (43.07%), while those with a symptomathology longer than 6 months had 74 locations with deposits (56.92%). Left knee was the most frequent location of UMS deposits (78.95%). Out of the 145 MSUS images with elementary lesions due to MSU crystal deposits, 28 were tophi (19.31%), 33 HA (22.75) and 84 DC (57.93%). Out of the total images with deposits (DC, HA and tophi), DC in the left knee was the most frequent (21.38%), followed by DC in right knee (17.24%) and DC in 1st MTP (10.24%).

Conclusion:

Almost 100% of patients with recently diagnosed gout without ULT, presented on at least one of the scanned locations MSUS images suggestive by MSU crystals deposition. Most of MSU crystals deposits were on knees and 1st MTP. Patients with non-treated longer than 6 months of disease duration gout had a greater number of MSU crystals deposit locations detected by MSUS. The presence of tophi and HA was statistically higher in patients with disease duration longer than 6 months (table 2).

Table 2.

MSU crystals median locations and MSUS images in both groups

<6months (n,%)>6months (n,%)p valueDeposits locations56 (43,07)74 (56,92)0,0751MSUS images with deposits -Tophi Median, IR () - HA Median, IR () - DC Median, IR ()8 (28,57) 0 (0-0) 7 (21,21) 0 (0-0) 39 (46,43) 0,5 (0-1)20 (71,43) 0 (0-1) 26 (78,79) 0 (0-1) 45 (53,57) 0 (0-2)0,01810,02310,8531

1Mann-Whitney U test comparing medians between both groups IR: interquartile range

References:

[1]Norkuviene E, Petraitis M, Apanaviciene I, Virviciute D and Baranauskaite A. An optimal ultrasonographic diagnostic test for early gout: A prospective controlled study. J Int Med Res. 2017 Aug.

[2]Neogi T, Jansen TLA A, Dalbeth N, Fransen J, Schumacher HR, Berendsen D et al. 2015 Gout Classification Criteria. An American College of Rheumatology/European League Against Rheumatism Collaborative Initiative. Arthritis & Rheumatology. Vol. 67, No. 10, October 2015.

Disclosure of Interests: :

Luis A Torrens Cid: None declared, Juan Molina Collada: None declared, Christian Y Soleto: None declared, Liz R. Caballero Motta: None declared, Ana Melissa Anzola Alfaro: None declared, Alfonso Ariza: None declared, Isabel Castrejón Fernández: None declared, Javier Rivera: None declared, Jose-Maria Alvaro-Gracia Grant/research support from: Abbvie, Elli-Lilly, MSD, Novartis, Pfizer, Consultant of: Abbvie, BMS, Janssen-Cilag, Elli-Lilly, MSD, Novartis, Pfizer, Sanofi, Tigenix, Roche, UCB, Paid instructor for: Elli-Lilly, Pfizer, Roche, Speakers bureau: Abbvie, BMS, Janssen-Cilag, Elli-Lilly, Gedeon Richter, MSD, Novartis, Pfizer, Sanofi, Tigenix, Roche, UCB, Juan Carlos Nieto Speakers bureau: Pfizer, Abbvie, MSD, Novartis, Janssen, Lilly, Nordic Pharma, BMS, Gebro, FAES Farma, Roche, Sanofi

AB0357 USE OF TOFACITINIB AND REASONS FOR DISCONTINUATION IN CLINICAL PRACTICE

Background:

Tofacitinib is an oral JAK 1 and 3 inhibitor for the treatment of moderate to severe active rheumatoid arthritis (RA) or psoriatic arthritis (PsA) in adults with inadequate response or intolerant to one or more conventional disease-modifying antirheumatic drugs (cDMARDs). Since its approval by the European Medicines Agency (EMA), there is limited data about its use in daily practice in Europe.

Objectives:

To describe rates and reasons for discontinuation of Tofacitinib in patients with RA and other inflammatory conditions

Methods:

We identified patients with a prescription for tofacitinib at our academic center from January 2017 to January 2020. Patients were treated according to their rheumatologist evaluation following standards of care. The following variables were retrospectively collected from the electronic medical chart: age, gender, diagnosis, date of treatment initiation, date and reasons for treatment discontinuation, the use of concomitant or previous cDMARDs and of biologics. A comparison between patients continuing and stopping tofacitinib was performed through chi2or t-test for qualitative and quantitative variables, respectively. Survival analysis was done by Kaplan-Meier method

Results:

Ninety patients receiving tofacitinib were identified, 81 with RA, 6 with PsA, 1 with Dermatomyositis, 1 with Sjögren´s and 1 with juvenile idiopathic arthritis. Table 1 shows the baseline characteristics. 84% percent patients were women and the mean (SD) age was 58.5 (14.2) years. 51% patients started tofacitinib in monotherapy. When used, methotrexate was the most frequent cDMARD (61.3%); 10% patients used tofacitinib as first line after cDMARD and the majority used it after 1 or 2 previous biologics (46.7%).

Table 2.

Clinical coutcome of patients who developed HZ at initiation of baricitinib

All patients(n=90, 100%)Continue Tofacitinib(n=58; 64%)Not continue Tofacitinib(n=32; 35.5%)p-valueFemale (%)76 (84.4)48 (82.7)28 (87.5)0.55Age (year) – mean (SD)58.5 (14.2)58 (12.9)59.5 (16.5)0.63Diagnosis0.66Rheumatoid arthritis81 (90)52 (89.6)29 (90.6)Psoriatic arthritis6 (6.7)4 (6.8)2 (6.2)Other3 (3.3)2 (3.4)1 (3.1)Treatment duration (months) – mean (SD)10.6 (6.9)11.9 (7.3)8.2 (5.5)0.02Prednisone (mg) – mean (SD)1.75 (3.2)1.20 (2.5)2.73 (4.1)0.03Monotherapy (%)46 (51.1)28 (48.2)18 (56.2)0.244Concomitant csDMARDs (%)44 (48.8)30 (51.7)14 (43.7)0.62Methotrexate (%)27 (30)17 (29.3)10 (31.2)Leflunomide (%)10 (11.1)8 (13.7)2 (6.2)Other (%)7 (7.7)5 (8.6)2 (6.2)Prior biologic treatment0.13None (%)9 (10)6 (10.3)3 (9.3)1-2 (%)42 (46.6)28 (48.2)14 (43.7)≥3 (%)39 (43.3)24 (41.3)15 (46.8)

Survival rates when used as first or second line were 85% at 6 months and 70% at 12 months; when used as third line or further, 76% and 70%, respectively (graphic 1).

Factors associated to tofacitinib discontinuation were treatment duration and baseline prednisone dose. In contrast concomitant csDMARD and number of previous biologics were not. Reasons for tofacitinib discontinuation were: lack/loss of efficacy 46.9%, adverse events 50% (including intolerance -22%- herpes zoster -16%-, other infections 12%) and others.

Conclusion:

Tofacitinib in our experience is mostly used in RA patients after biologic failure. Overall survival rate at 12 months was good regardless line of therapy. Adverse event rates were similar to other biologic treatments. Herpes zoster was the most common infectious AE.

Graphic 1:

References:

[1]Wollenhaupt J, Lee EB, Curtis JR, et al. Safety and efficacy of tofacitinib for up to 9.5 years in the treatment of rheumatoid arthritis: final results of a global, open-label, long-term extension study. Arthritis Res Ther. 2019;21(1):89.

Disclosure of Interests:

Christian Y Soleto: None declared, Belén Serrano Benavente: None declared, Luis A Torrens Cid: None declared, Julia Martínez-Barrio Consultant of: UCB Pharma, Juan Molina Collada: None declared, Javier Rivera: None declared, Teresa González: None declared, Indalecio Monteagudo: None declared, Carlos Gonzalez Consultant of: Gilead, Janssen, Novartis,, Speakers bureau: Abbvie, Celgene, Gilead, Janssen, Novartis, Pfizer, Roche, Isabel Castrejon: None declared, Jose-Maria Alvaro-Gracia Grant/research support from: Abbvie, Elli-Lilly, MSD, Novartis, Pfizer, Consultant of: Abbvie, BMS, Janssen-Cilag, Elli-Lilly, MSD, Novartis, Pfizer, Sanofi, Tigenix, Roche, UCB, Paid instructor for: Elli-Lilly, Pfizer, Roche, Speakers bureau: Abbvie, BMS, Janssen-Cilag, Elli-Lilly, Gedeon Richter, MSD, Novartis, Pfizer, Sanofi, Tigenix, Roche, UCB

AB0205 PREDICTORS OF ULTRASOUND DETECTED INFLAMMATORY FINDINGS IN PATIENTS WITH INFLAMMATORY ARTHRALGIA

Background:

Patients with inflammatory arthralgia (IA) are considered to be at increased risk for progression to RA. US has shown high sensitivity to detect synovitis compared with physical examination. Thus, US is recommended to identify subclinical synovitis in patients without clinical signs of inflammation.

Objectives:

The objective of our study is to determine the frequency and pattern of US detected inflammatory findings in patients with IA and investigate factors contributing to predict these findings.

Methods:

An US clinic is scheduled in an academic center running three days every week. A retrospective analysis of our US unit cohort during a period of 6 months was undertaken. Patients with IA and no previous diagnosis of inflammatory arthropathies were included for analysis. Inclusion criteria of IA definition included: severe symptoms presenting in the morning, duration of morning stiffness ≥60 min, symptoms predominantly located in MCP joints and abscense of clinically detected synovitis by the referral rheumatologist. The following routinely collected variables were included in the analysis: demographics, clinical features and laboratory tests. Patients underwent bilateral US examination in GS and PD mode of hands and/or feet according to the European League Against Rheumatism (EULAR) guidelines. The presence of synovitis, tenosynovitis and enthesitis was assessed on a semi quantitative scale (0–3) for Grey Scale(GS)/Power Doppler(PD) or using enthesitis OMERACT definition, respectively. Patients were stratified in two groups based on the presence of US inflammatory findings (synovitis, tenosynovitis or enthesitis with PD signal). First, differences between groups were tested using chi-squared and Student-t tests in the univariate analysis. Second, multivariate logistic regression models were employed to investigate the association between possible predictive factors of US detected inflammatory findings.

Results:

A total of 57 patients were included in the analysis. Mean age was 55.8±15.2 years, 41 (71.9%) were females, and mean symptoms duration was 11.4±10.4 months (Table 1). A total of 42 (73.7%) patients presented with a polyarticular arthralgia pattern. US inflammatory findings were present in 20 (35.1%) patients (26.3% PD synovitis, 21.1% PD tenosynovitis and 3.5% PD enthesitis). Hands were most commonly involved with PD synovitis at wrists in 19.3% and at MCP in 12.3% of patients (Table 2). For PD tenosynovitis, the flexor MCP 2-5 (5.3%) and compartment IV tenosynovitis (1.8 %) were the most frequent affected locations. Only two patients had PD enthesitis at feet and 6 (10.5%) had erosions in hands or feet at baseline examination. In the univariate analysis, the higher ESR values and the shorter time from symptoms onset were significantly associated with US detected inflammatory findings (p=0.044 and 0.049, respectively). In the multivariate analysis, only ESR values (OR=1,04; 95%CI 1,002-1,078), remained significantly associated with the presence of US inflammatory findings (Table 3).

Table 3.

Independent predictors of US detected inflammatory findings

pOdds ratio95% C.I.LowerUpperESR (mm/h)0.0391.041.0021.078Time (months) from symptoms onset0.10.9240.8411.015

Conclusion:

PD US inflammatory findings are found in 1 over 3 patients with IA being PD synovitis the most common finding, specially at the wrists and MCP joints. Higher ESR values were significantly associated with the presence of US inflammatory findings. Our data highlights how the use of PD US may be useful to detect subclinical synovitis in patients with IA.

Disclosure of Interests:

Katerine López Gloria: None declared, Isabel Castrejon: None declared, Laura Trives Folguera Speakers bureau: ROCHE, Juan Carlos Nieto Speakers bureau: Pfizer, Abbvie, MSD, Novartis, Janssen, Lilly, Nordic Pharma, BMS, Gebro, FAES Farma, Roche, Sanofi, Belén Serrano Benavente: None declared, Julia Martínez-Barrio Consultant of: UCB Pharma, Javier Rivera: None declared, Carlos Gonzalez Consultant of: Gilead, Janssen, Novartis,, Speakers bureau: Abbvie, Celgene, Gilead, Janssen, Novartis, Pfizer, Roche, Indalecio Monteagudo: None declared, Jose-Maria Alvaro-Gracia Grant/research support from: Abbvie, Elli-Lilly, MSD, Novartis, Pfizer, Consultant of: Abbvie, BMS, Janssen-Cilag, Elli-Lilly, MSD, Novartis, Pfizer, Sanofi, Tigenix, Roche, UCB, Paid instructor for: Elli-Lilly, Pfizer, Roche, Speakers bureau: Abbvie, BMS, Janssen-Cilag, Elli-Lilly, Gedeon Richter, MSD, Novartis, Pfizer, Sanofi, Tigenix, Roche, UCB, Juan Molina Collada: None declared

AB0431 SALIVARY GLAND ULTRASOUND IN CLINICAL PRACTICE

Background:

Sjogren’s syndrome (SS) is characterized by lymphocytic infiltration of the exocrine glands and marked B-lymphocytic cell hyperreactivity involving a variety of serum autoantibodies.1Salivary Gland Ultrasound (SGU) is a simple, fast, and well- tolerated examination, wich provides information about glandular structure and has proven to be very useful in the Sjögren Syndrome diagnosis2. A prognostic value has also been proposed due to its posible relationship with lymphomas and extra-glandular manifestations.

Objectives:

The objective of our study is to evaluate ultrasound results in patients who went through an SGU in clinical practice, its usefulness in the diagnosis of Sjögren’s syndrome and the presence of complications (lymphomas, extra-glandular manifestations or factors related to increased lymphoma risk).

Methods:

We conducted a retrospective cross-sectional study with review of clinical records that included all those patients coded as SGU in the Ultrasound unit of Rheumatology Department from 2016 to December 2019. Information collected included final diagnosis, laboratory results, clinical manifestations and ultrasound results. We performed an analysis on the frequency of pathological SGU and on the relationship between this lesions in patients with final SS diagnosis and the presence of lymphoma, extra-glandular manifestations and the laboratory values related with increased lymphoma risk (low complement levels, cryoglobulinemia, positive autoimmunity).

Results:

SGU was performed in 171 patients in four years, 162 women (94.7%). The previous diagnoses, reason for the request and final diagnosis are shown in Table 1. The vast majority of the SGU were normal, only 28 (16,3%) were pathological, 13 with a grade II and 8 with a grade III. In the other 7 patients grading was not available. Of the 28 patients with pathological SGU, none had lymphoma, only 3 had recurrent parotitis and 15 had had extra-glandular manifestations, mainly arthralgia / arthritis (12). Only 1 patient, with rheumatoid arthritis, had had a lymphoma and the SGU was normal. Antibody positivity was frequent in pathological SGU, 16/23 antinuclear antibodies, 13/22 anti-Ro and 9/23 rheumatoid factor. Of the 86 patients without previous diagnosis, 18 were diagnosed with Sjogren syndrome, 9 with pathological SGU and the rest were normal. No patient diagnosed with a dry non-autoimmune syndrome presented pathological SGU.

Table 1.

Previous diagnoses, reason for request and final diagnoses.

Previous diagnoses (n: 171)Reason for request (n: 171)Final diagnosis (n: 78)Without prior diagnosis (n: 86)Dry non- autoinmune syndrome (n: 127)Dry non-autoimmune syndrome (n: 60)Primary Sjögren’s syndrome (n: 11)Primary Sjögren’s syndrome (n: 12)Primary Sjögren’s syndrome (n: 18)Systemic Lupus Erythematosus (n: 9)Lymphoma (n: 0)Secondary Sjögren’s syndrome (n: 0)Rheumatoid arthritis (n: 24)Control (n: 13)Other diagnoses (n: 7)Other diagnoses (n: 18)Other reasons (n: 11)

Conclusion:

The impact of the SGU is low and its use cannot, for now, displace other methods (e.g. salivary gland biopsy) in the diagnosis of SS. Also our low number of patients with pathological SGU together with the low prevalence of the complications studied (e.g. lymphomas = 1) prevents the expected comparisons.

References:

[1]Ramos-Casals M, Solans R, Rosas J, et al. Primary Sjogren syndrome in Spain: clinical and immunologic expression in 1010 patients. Medicine (Baltimore) 2008; 87: 210–219.

[2]Damjanov N, Milic V, Nieto-Gonzalez JC, et al. Multiobserver Reliability of Ultrasound Assessment of Salivary Glands in Patients with Established Primary Sjogren Syndrome. J Rheumatology 2016; 43: 1858–1863.

Disclosure of Interests:

Fernando Montero: None declared, Karen Carpio: None declared, Iustina Janta: None declared, Juan Molina Collada: None declared, Belén Serrano Benavente: None declared, Julia Martínez-Barrio Consultant of: UCB Pharma, Alfonso Ariza: None declared, Javier Rivera: None declared, Carlos Gonzalez Consultant of: Gilead, Janssen, Novartis,, Speakers bureau: Abbvie, Celgene, Gilead, Janssen, Novartis, Pfizer, Roche, Indalecio Monteagudo: None declared, Juan Carlos Nieto Speakers bureau: Pfizer, Abbvie, MSD, Novartis, Janssen, Lilly, Nordic Pharma, BMS, Gebro, FAES Farma, Roche, Sanofi

AB1117 CLINICAL IMPACT OF MUSCULOSKELETAL ULTRASOUND ON RHEUMATOID ARTHRITIS IN ROUTINE CLINICAL PRACTICE

Background:

Musculoskeletal ultrasound (MSUS) is a useful tool to assess disease activity in rheumatoid arthritis (RA) patients. However, it has not yet been established if its use would change treatment decisions within a treat to target strategy or whether it would lead to better outcomes in RA patients

Objectives:

Our aim was to determine the impact of MSUS in the clinical management of RA patients and investigate factors associated with subsequent clinical actions by the referring rheumatologist

Methods:

A prospective analysis of RA patients seen at an MSUS clinic over a 6-month period was undertaken. Pre- and post-US follow-up data (± 3 months) were analyzed. Baseline assessment included clinical features, physical examination and laboratory tests. All MSUS examinations were performed according to EULAR guidelines and using an Esaote MyLab 8 (Esaote, Genoa) with a high frequency (8-15 MHz) transducer. Patients were stratified in groups based on the clinical impact of the MSUS visit: 1) No clinical impact and 2) US findings leading to subsequent clinical action by the referring rheumatologist (including changes in dosages of current rheumatologic treatments, addition/substraction of medications or interventional procedures based on the MSUS results). First, differences between groups were tested using chi-squared and Student-t tests in the univariate analysis. Second, multivariate logistic regression models were employed to investigate factors associated to a change in clinical management

Results:

A total of 61 RA patients were included for analysis. Mean age was 61.9± 11.4 years and 51 (83.6%) were female. Disease activity assessment was the most frequent referral reason (43; 70.5%). Overall, MSUS led to a subsequent therapeutic action by the referring rheumatologist in 39 (63.9%) patients, and to a change in the underlying diagnosis and/or in the clinical impression of the chief complaint that generated the referral in 7 (11.5%) patients. Baseline characteristics between both groups are compared in Table 1. In the univariate analysis, the detection of Power Doppler (PD) synovitis/tenosynovitis and 28 swollen joint count were significantly associated with a subsequent clinical action. In the multivariate analysis only PD synovitis/tenosynovitis (OR=3.28; 95%CI 1.06-10.27) remained significantly associated with a change in clinical management (Table 2)

Table 1.

Baseline characteristics of RA patients

Total n= 61Change in clinical management n= 39 (63.9%)No change in clinical management n= 22 (36.1%)pAge61.9±11.461.5±12.562.6±9.20.7SexFemale51(83.6%)35(89.7%)16(72.7%)0.09SmokingNon smoker33(54.1%)17(43.6%)16(72.7%)0.08Smoker13(21.3%)11(28.2%)2(9.1%)Former smoker15(24.6%)11(28.2%)13(21.3%)Radiographic erosions29(48.3%)22(57.9%)7(31.8%)0.0528 Tender Joint Count2.3±3.42.7±3.91.6±2.40.228 Swollen Joint Count2±32.6±3.51.1±1.6<0.05ESR (mm/h)28.1±20.626.1±15.531.7±27.40.4CRP (g/L)1±1.51±1.40.9±1.70.7RF (IU/mL)175.8±452.8139.9±249.5243.9±697.40.4ACPA (IU/mL)775.6±998.6619.4±797.11079.9±1,275.90.2US PD synovitis/tenosynovitis37(60.7%)28(71.8%)9(40.9%)<0.05Table 2.

Independent factors associated with a change in clinical management based on logistic regression model

pOdds ratio95% C.I.LowerUpper28 Tender Joint Count0.131.240.941.64US PD synovitis/tenosynovitis0.043.281.0610.17

Conclusion:

The most common indication of MSUS examination in RA patients was disease activity assessment. MSUS findings led frequent changes in therapeutic management and even to a change in the diagnosis in some of cases. The presence of PD synovitis/tenosynovitis was significantly associated to a change in the therapeutic management. These data highlight the impact of MSUS inflammatory findings in RA patients in daily clinical practice

Disclosure of Interests:

Juan Molina Collada: None declared, María Pérez: None declared, Isabel Castrejon: None declared, Juan Carlos Nieto Speakers bureau: Pfizer, Abbvie, MSD, Novartis, Janssen, Lilly, Nordic Pharma, BMS, Gebro, FAES Farma, Roche, Sanofi, Teresa González: None declared, Javier Rivera: None declared, Carlos Gonzalez Consultant of: Gilead, Janssen, Novartis,, Speakers bureau: Abbvie, Celgene, Gilead, Janssen, Novartis, Pfizer, Roche, Indalecio Monteagudo: None declared, Jose-Maria Alvaro-Gracia Grant/research support from: Abbvie, Elli-Lilly, MSD, Novartis, Pfizer, Consultant of: Abbvie, BMS, Janssen-Cilag, Elli-Lilly, MSD, Novartis, Pfizer, Sanofi, Tigenix, Roche, UCB, Paid instructor for: Elli-Lilly, Pfizer, Roche, Speakers bureau: Abbvie, BMS, Janssen-Cilag, Elli-Lilly, Gedeon Richter, MSD, Novartis, Pfizer, Sanofi, Tigenix, Roche, UCB

Abstract B36: Tracking the path of breast tumorigenesis in BRCA1 mutant breast cancer

Women with mutations in breast cancer (BrCa) gene BRCA1 are highly predisposed to BrCa. In these families, cancer develops almost exclusively in females and often at very young ages. The molecular pathogenic steps, especially the earliest ones that drive the transition of normal mammary epithelial cells (BRCA1mut/+) to tumor cells, are largely unknown. Mouse model-based studies have not successfully addressed this question, in part because, unlike women with BRCA1 (B1) mutations, B1 heterozygous mice do not form mammary tumors any faster than the wild-type (wt) mice. A mouse model that can biologically mimic what is happening in the mammary tissue of B1 mutation carriers would be an invaluable tool to study B1 mutant BrCa. Furthermore, most of the efforts to study breast tumor-associated gene changes have been based on GWAS studies or RNA-seq based analysis of the breast tumor samples. Such studies have shown that the transcriptional network is altered in the breast tumors compared to wild-type tissue. However, whether those changes are tumor initiating, i.e., “driver” changes, or are “passenger” mutations/changes is still not clear. Given the role of B1 in suppressing replication stress (RS), a tumor-promoting event, and the increased RS observed in B1 heterozygous cells, we have established an RS-driven B1 BrCa mouse model to study the early genetic changes that drive B1 mutant cancer. We find that intraductal injections of 4-nitroquinoline-1-oxide (4NQO1, a replication stress-inducing agent) leads to breast adenocarcinoma in B1flx/wt;Trp53flx/flx,K14Cre mice on average 84 days post injections unlike B1 wt mice that do not make tumors. This is the first RS-induced BrCa model that can successfully recapitulate B1 mutant BrCa. The fast timeline of tumor formation provides significant advantage for studying tumor formation, progression, and response to therapy. Furthermore, single-cell RNA sequencing analysis of the breast adenocarcinoma and tissue collected early during injections in these mice has revealed presence of a highly proliferative “transdifferentiated population” that shares properties of both luminal and basal cells (e.g., K8+K18+) and also exists in the hyperplastic tissue. No such population was found in control PBS injected mammary fat pad of B1flx/wt;Trp53flx/flx,K14Cre mice, indicating that this population might be dependent on RS. We also find that this population is enriched very early during mammary tumorigenesis and some of the top hits include cancer stem cell markers. We have also confirmed the presence of this population by immune histochemistry-based experiments. Finally, our study provides evidence for a BrCa mouse model where basal-like tumor formation is driven by RS. We also found evidence for an early precancerous transdifferentiated population that is enriched upon RS and have identified early markers that can potentially drive breast tumorigenesis in B1 mutant BrCa. Identification of such candidate genes is critical in the design of future preventive and/or therapeutic strategies.

Citation Format: Joshua Rivera, Delan Khalid, Stevenson Tran, Kemmie Kibaja, Shailja Pathania. Tracking the path of breast tumorigenesis in BRCA1 mutant breast cancer [abstract]. In: Proceedings of the AACR Special Conference on the Evolving Landscape of Cancer Modeling; 2020 Mar 2-5; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2020;80(11 Suppl):Abstract nr B36.

A New Species of Praying Mantis from Peru Reveals Impaling as a Novel Hunting Strategy in Mantodea (Thespidae: Thespini)

A new species of lichen-mimicking praying mantis, Carrikerella simpira n. sp., is described from Tingo María region in Peru. The new species differs from its congeners in having reduced tergal lobes, a relatively sinuous pronotum, and it is found in the highland tropical rainforest of the Central Andes. Behavioral observations conducted on captive individuals revealed that juveniles and adults hunt by impaling prey using modified foretibial structures. Anatomical examinations of the incumbent trophic structures revealed functional adaptations for prey impaling in the foretibiae, primarily consisting of prominent, forwardly oriented, barbed spines. We provide an overall description of this novel hunting behavior in Mantodea and hypothesize on its evolutionary origin and adaptive significance for the Thespidae.

Closure of L3 pedicle subtraction osteotomy via an open-bottom hinged table in 3D video

Iatrogenic flat back deformity generally can be treated with a pedicle subtraction osteotomy (PSO) (Chan et al., 2018; Lu and Chou, 2007). One of the difficulties with PSO is that a controlled closure can sometimes be problematic in that there may be translation of the spine, manual pushing of the spine, and significant stress on the pedicle screws, which may risk loosening. The authors present a video of their surgical technique for PSO closed by passive closure using an open-bottom hinged table. This allows the osteotomy to be closed without any force on the screws and without significant manual forces on the spinal column. The video can be found here: https://youtu.be/pUECEjKdmSk.

Navigated oblique lumbar interbody fusion for adult spinal deformity

Adult spinal deformity (ASD) is an increasing disease entity as the population ages. An emerging minimally invasive surgery (MIS) option for the treatment of ASD is the oblique lumbar interbody fusion (OLIF), which allows indirect foraminal decompression of stenosis as well as segmental deformity correction (DiGiorgio et al., 2017). The authors utilize computer-assisted navigation with OLIF to reduce radiation exposure and improve time efficiency. The authors present a video of navigated oblique lumbar interbody fusion at L3–5 followed by open posterior screw-rod fixation.

The video can be found here: https://youtu.be/zKDT7PhMYf8.

Multiresidue Determination of Pesticides in Drinking and Related Waters by Solid-Phase Extraction and Liquid Chromatography with Ultraviolet Detection: Interlaboratory Study

As part of a project funded by the European Commission (EC) for the development and evaluation of multiresidue methods for analysis of drinking and related waters, 17 European laboratories evaluated a method using styrene–divinylbenzene copolymer solid-phase extraction followed by liquid chromatography with diode array detection. The main aim of the study was to evaluate whether the method meets the requirements of EC Drinking Water Directive 98/83 in terms of accuracy, precision, and detection limit for 21 pesticides according to the following requirements: limit of detection, ≤0.025 μg/L; accuracy expressed as recovery, between 75 and 125%; and precision expressed as repeatability relative standard deviation of the method, &lt;12.5%, and as reproducibility relative standard deviation of the method, &lt;25%. Analyses for unknown concentrations were performed with commercial bottled and tap waters. All laboratories were able to achieve detection limits of 0.01 μg/L for all pesticides except pirimicarb (0.02 μg/L). The criteria for repeatability were met for all compounds. Terbutryn in bottled water and carbendazim in tap water did not meet the criteria for reproducibility. In terms of accuracy, the method met the requirements for all pesticides in both matrixes, except for metamitron. However, several compounds (linuron, terbutryn, propazine, metobromuron, and isoproturon) showed recoveries slightly below 75%.

Multiresidue Determination of Pesticides in Drinking and Related Waters by Gas Chromatography/Mass Spectrometry after Solid-Phase Extraction: Interlaboratory Study

As part of a project funded by the European Commission (EC) for the development and evaluation of multiresidue methods for analysis of drinking and related waters, 15 European laboratories evaluated a method using styrene–divinylbenzene copolymer solid-phase extraction followed by gas chromatography/mass spectrometry. The main aim of the study was to evaluate whether the method meets the requirements of EC Directive 98/83 in terms of accuracy, precision, and detection limit for 22 pesticides according to the following requirements: limit of detection, ≤0.025 μg/L; accuracy, expressed as recovery between 75 and 125%; and precision, expressed as repeatability relative standard deviation of the method of &lt;12.5% and as reproducibility relative standard deviation of the method of &lt;25%. Analyses for unknown concentrations were performed with fortified commercial bottled and tap waters. All laboratories were able to achieve detection limits of 0.01 μg/L for all pesticides except dimethoate and desisopropylatrazine (0.02 μg/L). The criteria for repeatability were met for all compounds except trifluralin, dimethoate, and lindane in bottled water and chlorpyrifos, dimethoate, and lindane in tap water. The criteria for reproducibility were met for all compounds except trifluralin, dimethoate, and lindane in bottled water and pendimethalin, chlorpyrifos, dimethoate, terbutryn, and lindane in tap water. In terms of accuracy, the method meets the requirements for all pesticides in both matrixes, except for lindane in bottled water and lindane and chlorpyrifos in tap water.