[Antitumor effects of redox-responsive nanoparticles containing platinum（Ⅳ）in ovarian cancer]

Objectives: To explore the antitumor effects of redox-responsive nanoparticles containing platinum(Ⅳ)-NP@Pt(Ⅳ) in ovarian cancer. Methods: Redox-responsive polymer carriers were synthesized. Polymer carriers and platinum(Ⅳ)-Pt(Ⅳ) can self-assemble into NP@Pt(Ⅳ). Inductively coupled plasma mass spectrometry was performed to detect the platinum release from NP@Pt(Ⅳ) in reducing environment and the platinum content in ovarian cancer cells ES2 treated with cisplatin, Pt(Ⅳ) and NP@Pt(Ⅳ). The proliferation ability of the ovarian cancer cells were detected by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cellular apoptosis was assessed by flow cytometry. Collection of primary ovarian cancer tissues from patients with primary high-grade serous ovarian cancer who were surgically treated at the Cancer Hospital of the Chinese Academy of Medical Sciences from October to December 2022. The high-grade serous ovarian cancer patient-derived xenograft (PDX) mice were intravenously injected with Cy7.5 labeled NP@Pt(Ⅳ) followed by in vivo imaging system. Mice were treated with PBS, cisplatin and NP@Pt(Ⅳ). Tumor volume and weight were measured in each group. Necrosis, apoptosis and cell proliferation of tumor tissues were detected by hematoxylin-eosin (HE) staining, TUNEL fluorescence staining and Ki-67 immunohistochemistry staining. Body weight and HE staining of heart, liver, spleen, lung and kidney of mice in each group were measured. Results: The platinum release of NP@Pt(Ⅳ) after 48 hours in reducing environment was 76.29%, which was significantly higher than that of 26.82% in non-reducing environment (P<0.001). The platinum content in ES2 cells after 4 hours and 7 hours of treatment with NP@Pt(Ⅳ) (308.59, 553.15 ng/million cells) were significantly higher than those of Pt(Ⅳ) (100.21, 180.31 ng/million cells) and cisplatin (43.36, 50.36 ng/million cells, P＜0.05). The half inhibitory concentrations of NP@Pt(Ⅳ) in ovarian cancer cells ES2, A2780, A2780DDP were 1.39, 1.42 and 4.62 μmol/L, respectively, which were lower than those of Pt(IV) (2.89, 7.27, and 16.74 μmol/L) and cisplatin (5.21, 11.85, and 71.98 μmol/L). The apoptosis rate of ES2 cells treated with NP@Pt(Ⅳ) was (33.91±3.80)%, which was significantly higher than that of Pt(Ⅳ) [(16.28±2.41)%] and cisplatin [(15.01±1.17)%, P＜0.05]. In high-grade serous ovarian cancer PDX model, targeted accumulation of Cy7.5 labeled NP@Pt(Ⅳ) at tumor tissue could be observed. After the treatment, the tumor volume of mice in NP@Pt(IV) group was (130±98) mm3, which was significantly lower than those in control group [(1 349±161) mm3, P<0.001] and cisplatin group [(715±293) mm3, P=0.026]. The tumor weight of mice in NP@Pt(IV) group was (0.17±0.09)g, which was significantly lower than those in control group [(1.55±0.11)g, P<0.001] and cisplatin group [(0.82±0.38)g, P=0.029]. The areas of tumor necrosis and apoptosis in mice treated with NP@Pt(Ⅳ) were higher than those in mice treated with cisplatin. Immunohistochemical staining revealed that there were low expressions of Ki-67 at tumor tissues of mice treated with NP@Pt(Ⅳ) compared with cisplatin. The change in body weight of mice in NP@Pt(Ⅳ) group was not significantly different from that of the control group [(18.56±2.04)g vs.(20.87±0.79)g, P=0.063]. Moreover, the major organs of the heart, liver, spleen, lung, and kidney were also normal by HE staining. Conclusion: Redox-responsive NP@Pt(Ⅳ), produced in this study can enhance the accumulation of cisplatin in ovarian cancer cells and improve the efficacy of ovarian cancer chemotherapy.

Bone Mineral Density T-Score is an Independent Predictor of Major Blood Loss in Adult Spinal Deformity Surgery

STUDY DESIGN

Retrospective Cohort Study.

OBJECTIVE

The purpose of this study was to determine the effect of low bone mineral density (BMD), as assessed by preoperative Dual-energy X-ray Absorptiometry (DEXA) scans, on intraoperative blood loss following adult spinal deformity (ASD) surgery.

METHODS

Patients who received spinal fusion for ASD (>5 levels fused) at a single academic center from 2010-2018 were included in this study. The lowest preoperative T-score was recorded for patients who had preoperative DEXA scans within a year of surgery. Patients with liver/kidney disease or on prescription anticoagulant medication were excluded. Major blood loss was a binary variable defined as above or below the 90th percentile of our cohort. Binomial regression was performed controlling for age, number of vertebrae fused, 3-column osteotomy, primary vs. revision surgery, preoperative platelet count, and if the patient was taking medication for osteoporosis.

RESULTS

91 patients were identified in the cohort. Mean age was 63 ± 11.6 years, 81% female. 56 (62%) of cases included revision of previous instrumentation. Patients had a mean SVA of 9.6 ± 8.6 cm and median of 9 vertebrae fused (range 5-22). The average T-score was -1.2 ± 1.0. Each point lower T-score was associated with significantly higher odds of major blood loss (OR 2.5, 95% CI 1.0 - 5.9) when controlling for age, number of vertebrae fused, 3-column osteotomy, preoperative platelet count and primary vs. revision surgery.

CONCLUSIONS

Preoperative T-score is independently associated with increased odds of major blood loss in ASD surgery.

Outpatient Versus Inpatient Total Shoulder Arthroplasty: A Matched Cohort Analysis of Postoperative Complications, Surgical Outcomes, and Reimbursements

INTRODUCTION

There has been a trend toward performing arthroplasty in the ambulatory setting. The primary purpose of this study was to compare outpatient and inpatient total shoulder arthroplasties (TSAs) for postoperative medical complications, healthcare utilization outcomes, and surgical outcomes.

METHODS

Patients who underwent outpatient TSA or inpatient TSA with a minimum 5-year follow-up were identified in the PearlDiver database. These cohorts were propensity-matched based on age, sex, Charlson Comorbidity Index, smoking status, and obesity (body mass index > 30). All outcomes were analyzed using chi square and Student t-tests where appropriate.

RESULTS

Outpatient TSA patients had markedly lower rates of various 90-day medical complications. Outpatient TSA patients had lower risk of aseptic loosening at 2 years postoperation and lower risk of periprosthetic joint infection at 5 years postoperation relative to inpatient TSA patients. Outpatient TSA reimbursements were markedly lower than inpatient TSA reimbursements at the 30-day, 90-day, and 1-year postoperative intervals.

CONCLUSION

This study found patients undergoing outpatient TSA to be at lowers odds for both postoperative medical and surgical complications compared with those undergoing inpatient TSA. Despite increased risk of postoperative healthcare utilization for readmissions and emergency department visits, outpatient TSA was markedly less expensive at every postoperative time point assessed.

The influence of elevated international normalized ratio on complications following total shoulder arthroplasty

Background

Identifying preoperative risk factors for complications following total shoulder arthroplasty (TSA) has both clinical and financial implications. The purpose of this study was to determine the influence of different degrees of preoperative INR elevation on complications following TSA.

Methods

Patients undergoing primary TSA from 2007 to 2018 were identified in a national database. Patients were stratified into 4 cohorts: INR of <1.0, INR of >1.0 to 1.25, INR of >1.25 to 1.5, and INR of >1.5. Postoperative complications were assessed. Multivariate logistic regressions were performed to adjust for differences in demographics and comorbidities among the INR groups.

Results

Following adjustment and relative to patients with an INR of <1.0, those with INR of >1.0-1.25, >1.25-1.5, and >1.5 had 1.6-times, 2.4-times, and 2.8-times higher odds of having postoperative bleeding requiring transfusion, respectively (p < 0.05 for all). Relative to patients with INR <1.0, those with INR of > 1.25-1.5 and INR of >1.5 had 7.8-times and 7.0-times higher odds of having pulmonary complications, respectively (p < 0.05 for both).

Discussion

With increasing INR levels, there is an independent and step-wise increase in odd ratios for postoperative complications. Current guidelines for preoperative INR thresholds may need to be adjusted for more predictive risk-stratification for TSA.

Level of Evidence

III.

Epidemiology of shoulder instability procedures: A comprehensive analysis of complications and costs

Background

Recurrent shoulder instability is a debilitating condition that can lead to chronic pain, decreased function, and inability to return to activities or sport. This retrospective epidemiology study was performed to report 90-day postoperative complications and costs of Latarjet, anterior bone block reconstruction, arthroscopic, and open Bankart repair for shoulder instability.

Methods

Patients 18 years and older who underwent four primary shoulder surgeries from 2010 to 2019 were identified using national claims data. Patient demographics, comorbidities, and 90-day postoperative complications were analyzed using univariate analysis and multivariable logistic regression. Total and itemized 90-day reimbursements were determined for each procedure.

Results

The 90-day medical and surgery-specific complication rates were highest for anterior bone block reconstruction, followed by Latarjet. Arthroscopic Bankart repair had the highest 90-day costs and primary procedure costs compared to other procedures.

Conclusion

Anterior bone block reconstruction and Latarjet procedures were associated with the highest rates of 90-day medical and surgery-specific complications, while arthroscopic Bankart repair was associated with the highest costs.

Racial Disparities in Spine Surgery: A Systematic Review

STUDY DESIGN

Systematic Review.

OBJECTIVES

To synthesize previous studies evaluating racial disparities in spine surgery.

METHODS

We queried PubMed, Embase, Cochrane Library, and Web of Science for literature on racial disparities in spine surgery. Our review was constructed in accordance with Preferred Reporting Items and Meta-analyses guidelines and protocol. The main outcome measures were the occurrence of racial disparities in postoperative outcomes, mortality, surgical management, readmissions, and length of stay.

RESULTS

A total of 1753 publications were assessed. Twenty-two articles met inclusion criteria. Seventeen studies compared Whites (Ws) and African Americans (AAs) groups; 14 studies reported adverse outcomes for AAs. When compared with Ws, AA patients had higher odds of postoperative complications including mortality, cerebrospinal fluid leak, nervous system complications, bleeding, infection, in-hospital complications, adverse discharge disposition, and delay in diagnosis. Further, AAs were found to have increased odds of readmission and longer length of stay. Finally, AAs were found to have higher odds of nonoperative treatment for spinal cord injury, were more likely to undergo posterior approach in the treatment of cervical spondylotic myelopathy, and were less likely to receive cervical disk arthroplasty compared with Ws for similar indications.

CONCLUSIONS

This systematic review of spine literature found that when compared with W patients, AA patients had worse health outcomes. Further investigation of root causes of these racial disparities in spine surgery is warranted.

Presence and Severity of Mental Illness Is Associated With Increased Risk of Postoperative Emergency Visits, Readmission, and Reoperation Following Outpatient ACDF: A National Database Analysis

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The purpose was to compare rates of postoperative ED visits, readmission, and reoperation between patients with and without preexisting mental illness undergoing outpatient anterior cervical discectomy and fusion (ACDF).

METHODS

A retrospective review of the Mariner Database was conducted on patients who underwent ACDF between 2010 and 2017. Exclusion criteria included same day revision surgery and patients with a history of spine infection, trauma, or neoplasm. Patients were grouped into 3 categories: those with existing history of anxiety and/or depression, those with severe mental illness, and those without any history of mental illness. Severe mental illness was defined as a combination of diagnosis including schizophrenia, bipolar disorder, and/or psychotic disorder. Outcome measures were analyzed by comparing groups using multivariate logistic regression. Significance was set at P < 0.05.

RESULTS

Patients with anxiety/depression and patients with severe mental illness both had significantly increased risk of ED visits and readmission at 30-day and 90-day intervals. Compared to patients without mental illness, patients with severe mental illness (OR 1.93, P < 0.001) had significantly increased rates of reoperation at 90-days and 1-years postoperatively. Patients with anxiety/depression did not have increased rates of reoperation relative to patients without anxiety/depression at any time interval (P > 0.05).

CONCLUSION

Anxiety/depression as well as more severe psychiatric disease such as Schizophrenia and Bipolar disorder were significantly associated with increased healthcare utilization following outpatient ACDF. Patients with preexisting mental illness undergoing outpatient ACDF should be carefully evaluated preoperatively and closely followed postoperatively to reduce risk of adverse events.

Sarcopenia as a Risk Factor for Complications Following Pedicle Subtraction Osteotomy

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

The objective was to determine if sarcopenia is an independent risk factor for complications in adult spinal deformity (ASD) patients undergoing pedicle subtraction osteotomy (PSO) and define categories of complication risk by sarcopenia severity.

SUMMARY OF BACKGROUND DATA

Sarcopenia is linked to morbidity and mortality in several orthopedic procedures. Data concerning sarcopenia in ASD surgery is limited, particularly with respect to complex techniques performed such as PSO. With the high surgical burden of PSOs, appropriate patient selection is critical for minimizing complications.

METHODS

We identified 73 ASD patients with lumbar CT/MRI scans who underwent PSO with spinal fusion ≥5 levels at a tertiary care center from 2005 to 2014. Sarcopenia was assessed by the psoas-lumbar vertebral index (PLVI). Using stratum-specific likelihood ratio analysis, patients were separated into 3 sarcopenia groups by complication risk. The primary outcome measure was any 2-year complication. Secondary outcome measures included intraoperative blood loss and length of stay.

RESULTS

The mean PLVI was 0.84±0.28, with 47% of patients having complications. Patients with a complication had a 27% lower PLVI on average than those without complications (0.76 vs. 0.91, P=0.021). Stratum-specific likelihood ratio analysis produced 3 complication categories: 32% complication rate for PLVI ≥ 0.81; 61% for PLVI 0.60-0.80; and 69% for PLVI < 0.60. Relative to patients with PLVI ≥ 0.81, those with PLVI 0.60-0.80 and PLVI < 0.60 had 3.2× and 4.3× greater odds of developing a complication (P<0.05). For individual complications, patients with PLVI < 1.0 had a significantly higher risk of proximal junctional kyphosis (34% vs. 0%, P=0.022), while patients with PLVI < 0.8 had a significantly higher risk of wound infection (12% vs. 0%, P=0.028) and dural tear (14% vs. 0%, P=0.019). There were no significant associations between sarcopenia, intraoperative blood loss, and length of stay.

CONCLUSIONS

The increasing severity of sarcopenia is associated with a significantly and incrementally increased risk of complications following ASD surgery that require PSO.

LEVEL OF EVIDENCE

Level III.

[Signal transducer and activator of transcription 3 and cancer associated fibroblasts jointly generate chemo-resistance and affect prognosis in epithelial ovarian cancer]

Objective: To investigate the mechanism of signal transducer and activator of transcription 3 (STAT3) and cancer associated fibroblasts (CAF) jointly generate chemo-resistance in epithelial-ovarian cancer and their effect on prognosis. Methods: A total of 119 patients with high-grade ovarian serous cancer who received surgery in Cancer Hospital of Chinese Academy of Medical Sciences from September 2009 to October 2017 were collected. The clinico-pathological data and follow-up data were complete. Multivariate Cox regression model was used to analyze the prognostic factors. Ovarian cancer tissue chips of patients in our hospital were prepared. EnVision two-step method immunohistochemistry was used to detect the protein expression levels of STAT3, the specific markers of CAF activation, fibroblast activating protein (FAP), and type Ⅰ collagen (COL1A1) secreted by CAF. The relationship between the expression of STAT3, FAP, COL1A1 protein and drug resistance and prognosis of ovarian cancer patients was analyzed, and the correlation between the expression of three proteins was analyzed. These results were verified through the gene expression and prognostic information of human ovarian cancer tissues collected in the GSE26712 dataset of gene expression omnibus (GEO) database. Results: (1) Multivariate Cox regression model analysis showed that chemotherapy resistance was an independent risk factor for overall survival (OS) of ovarian cancer (P<0.001). (2) The expression levels of STAT3, FAP, and COL1A1 proteins in chemotherapy resistant patients were significantly higher than those in chemotherapy sensitive patients (all P<0.05). Patients with high expression of STAT3, FAP, and COL1A1 had significantly shorter OS than those with low expression (all P<0.05). According to the human ovarian cancer GSE26712 dataset of GEO database, patients with high expression of STAT3, FAP, and COL1A1 also showed shorter OS than patients with low expression (all P<0.05), the verification results were consistent with the detection results of ovarian cancer patients in our hospital. (3) Correlation analysis showed that the protein level of STAT3 was positively correlated with FAP and COL1A1 in our hospital's ovarian cancer tissue chips (r=0.47, P<0.001; r=0.30, P=0.006), the analysis of GEO database GSE26712 dataset showed that the expression of STAT3 gene and FAP, COL1A1 gene were also significantly positively correlated (r=0.31, P<0.001; r=0.52, P<0.001). Conclusion: STAT3 and CAF could promote chemotherapy resistance of ovarian cancer and lead to poor prognosis.

Laminectomy vs Fusion for Intradural Extramedullary Tumors

BACKGROUND

Laminectomy (LA) and LA with fusion (LAF) have been demonstrated as surgical techniques that treat intradural extramedullary tumors (IDEMTs). The purpose of the present study was to compare the rate of 30-day complications following LA vs LAF for IDEMTs.

METHODS

Patients undergoing LA for IDEMTs from 2012 to 2018 were identified in the National Surgical Quality Improvement Program database. Patients undergoing LA for IDEMTs were substratified into 2 cohorts: those who received LAF and those who did not. In this analysis, preoperative patient characteristics and demographic variables were assessed. 30-day wound, sepsis, cardiac, pulmonary, renal, and thromboembolic complications, as well as mortality, postoperative transfusions, extended length of stay, and reoperation, were assessed. Bivariate analyses, including χ ² and t tests, and multivariable logistical regression were performed.

RESULTS

Of 2027 total patients undergoing LA for IDEMTs, 181 (9%) also had fusion. There were 72/373 (19%) LAF in the cervical region, 67/801 (8%) LAF in the thoracic region, and 42/776 (5%) LAF in the lumbar region. Following adjustment, patients who received LAF were more likely to have increased length of stay (OR 2.73, P < 0.001) and increased rate of postoperative transfusion (OR 3.15, P < 0.001). Patients undergoing LA in the cervical spine for IDEMTs tended to receive additional fusion (P < 0.001).

CONCLUSIONS

Increased length of stay and rate of postoperative transfusion were associated with LAF for IDEMTs. LA in the cervical spine for IDEMTs was associated with additional fusion.

LEVEL OF EVIDENCE: 3

SLAP repair and bicep tenodesis: a comparison of utilization and revision rates for SLAP tears

Hypothesis

The management of superior labrum anterior to posterior (SLAP) tears typically consists of either repair or biceps tenodesis (BT). While repair is more frequently recommended in younger patients, patients older than 40 years are often treated with BT. The purpose of this study is to determine whether there has been a change in utilization of these procedures over the past decade with respect to patient age as well as compare reoperation rates between the two procedures.

Methods

The Pearldiver database was queried to identify BT and SLAP repairs indicated for SLAP tears performed from 2010 to 2019. The primary outcome was utilization rate, stratified by age. A secondary outcome was 2-year shoulder reoperation rates. Trends were reported in terms of compounded annual growth rate. Outcome analysis was conducted using univariate and multivariable analysis.

Results

From 2010 to 2019, SLAP repair was the most common procedure performed for SLAP tears. Regardless of age, BT performed for SLAP tear had a significantly increased utilization rate; whereas, SLAP repair had a significantly decreased utilization rate. SLAP repair was more commonly performed in younger patients compared to BT. Following multivariable analysis, patients who underwent SLAP repair had significantly higher odds (odds ratio (OR): 1.453; 95% confidence interval (CI): 1.26-1.68; P < .001) of requiring an arthroscopic reoperation within 2 years when compared to those who underwent BT with no significant difference with respect to 2-year open reoperation.

Conclusion

Although SLAP repair is still more commonly used to treat SLAP tears than BT, especially for younger patients, the utilization of SLAP repair is decreasing while BT is increasing. The increased utilization of BT may be associated with lower rates of shoulder reoperation for problematic SLAP tears.

Social Media Presence Is Associated With Diversity and Application Volume for Orthopedic Surgery Residency Programs

The purpose of this study was to assess the association between social media presence (Twitter and Instagram), diversity in orthopedic surgery residency programs, and the number of applications received by a program. Data from Twitter and Instagram for 179 orthopedic residency programs accredited by the Accreditation Council for Graduate Medical Education were collected, including the presence of a social media account, date of first post, number of posts, and number of followers. Residency program data were collected from the Association of American Medical Colleges Residency Explorer Tool and included percentage of Whiteresidents, percentage of male residents, residency ranking, and number of applications submitted during the 2019 application cycle. Bivariate and multivariable analyses were performed with adjustment for program ranking. Of 179 residency programs, 34.6% (n=62) had Twitter, and 16.7% (n=30) had Instagram. Overall, 39.7% (n=71) had a social media presence, defined as having at least one of the two forms of social media. Programs with social media presences had higher average rankings (48.1 vs 99.6 rank, P<.001). After adjusting for program ranking, social media presence was associated with increased applications during the 2019 application cycle (odds ratio [OR]=2.76, P=.010). Social media presence was associated with increased odds of gender diversity (OR=3.07, P=.047) and racial diversity (OR=2.21, P=.041). Individually, Twitter presence was associated with increased odds of gender (OR=4.81, P=.018) and racial diversity (OR=4.00, P=.021), but Instagram was not (P>.05). Social media presence is associated with more residency program applications and increased resident diversity. Social media can be used to highlight inclusivity measures and related opportunities. [Orthopedics. 2023;46(1):47-53.].

Return to work after adult spinal deformity surgery

PURPOSE

To determine the proportions of patients returning to work at various points after adult spinal deformity (ASD) surgery and the associations between surgical invasiveness and time to return to work.

METHODS

Using a multicenter database of patients treated surgically for ASD from 2008 to 2015, we identified 188 patients (mean age 51 ± 15 years) who self-reported as employed preoperatively and had 2-year follow-up. Per the ASD-Surgical and Radiographical Invasiveness Index (ASD-SR), 118 patients (63%) underwent high-invasiveness (HI) surgery (ASD-SR ≥ 100) and 70 (37%) had low-invasiveness (LI) surgery (ASD-SR < 100). Patients who self-reported ≥ 75% normal level of work/school activity were considered to be working full time. Chi-squared and Fisher exact tests were used to compare categorical variables (α = .05).

RESULTS

Preoperatively, 69% of employed patients worked full time. Postoperatively, 15% of employed patients were full time at 6 weeks, 70% at 6 months, 83% at 1 year, and 84% at 2 years. Percentage of employed patients working full time at 2 years was greater than preoperatively (p < .001); percentage of patients returning to full time at 6 weeks was lower in the HI (5%) than in the LI group (19%) (p = .03), a difference not significant at later points.

CONCLUSIONS

Most adults returned to full-time work after ASD surgery. A smaller percentage of patients in the HI group than in the LI group returned to full-time work at 6 weeks. Patients employed full time preoperatively will likely return to full-time employment after ASD surgery.

LEVEL OF EVIDENCE

III.

Bilateral Total Knee Arthroplasty: Current Concepts Review

»

Bilateral total knee arthroplasty (BTKA) is an effective surgical treatment for bilateral knee arthritis and can be performed as a simultaneous surgery under a single anesthetic setting or as staged surgeries on separate days.

»

Appropriate patient selection is important for simultaneous BTKA with several factors coming into consideration such as age, comorbidities, work status, and home support, among others.

»

While simultaneous BTKA is safe when performed on appropriately selected patients, current evidence suggests that the risk of complications after simultaneous BTKA remains higher than for staged BTKA.

»

When staged surgery is preferred, current evidence indicates that complication risks are minimized if the 2 knees are staged at least 3 months apart.

»

Simultaneous BTKA is the economically advantageous treatment option relative to staged BTKA, primarily because of shorter total operative time and total hospital stay.

Preoperative patient activation predicts minimum clinically important difference for PROMIS pain and physical function in patients undergoing elective spine surgery

BACKGROUND CONTEXT

Patient activation is a patient's willingness to take independent actions to manage their own health care.

PURPOSE

The goal of this study is to determine whether preoperative patient activation measure (PAM) predicts minimum clinically important difference (MCID) for Patient-Reported Outcomes Measurement Information System (PROMIS) pain, physical function, depression, and anxiety for patients undergoing elective spine surgery.

STUDY DESIGN/SETTING

Retrospective review.

PATIENT SAMPLE

A single-institution, academic database of patients undergoing elective spine surgery.

OUTCOME MEASURE

MCID at 1-year follow-up for PROMIS pain, physical function, depression and anxiety.

METHODS

We retrospectively reviewed a single-institution, academic database of patients undergoing elective spine surgery. Preoperative patient activation was evaluated using the PAM-13 survey, which was used to stratify patients into four activation stages. Primary outcome variable was achieving MCID at 1-year follow-up for PROMIS pain and physical function. Multivariable logistic regression analysis was used to determine impact of patient activation on PROMIS pain and the physical function.

RESULTS

Of the 430 patients, 220 (51%) were female with a mean age of 58.2±16.8. Preoperatively, 34 (8%) were in activation stage 1, 45 (10%) in stage 2, 98 (23%) in stage 3, and 253 (59%) in stage 4. At 1-year follow up, 248 (58%) achieved MCID for PROMIS physical function, 256 (60%) achieved MCID for PROMIS pain, 151 (35.28%) achieved MCID for PROMIS depression, and 197 (46%) achieved MCID for PROMIS anxiety. For PROMIS physical function, when compared to patients at stage 1 activation, patients at stage 2 (aOR:3.49, 95% CI:1.27, 9.59), stage 3 (aOR:3.54, 95% CI:1.40, 8.98) and stage 4 (aOR:7.88, 95% CI:3.29, 18.9) were more likely to achieve MCID. For PROMIS pain, when compared against patients at stage 1, patients at stage 3 (aOR:2.82, 95% CI:1.18, 6.76) and stage 4 (aOR:5.44, 95% CI:2.41, 12.3) were more likely to achieve MCID. For PROMIS depression, when compared against patients at stage 1, patients at stage 4 were more likely to achieve MCID (Adjusted Odds Ratio (aOR):2.59, 95% CI:1.08-6.19). For PROMIS anxiety, when compared against patients at stage 1, stage 3 (Adjusted Odds Ratio (aOR):3.21, 95% CI:1.20-8.57), and stage 4 (aOR:5.56, 95% CI:2.20-14.01) were more likely to achieve MCID.

CONCLUSION

Patients at higher stages of activation were more likely to achieve MCID for PROMIS pain, physical function, depression, and anxiety at 1-year follow-up. Routine preoperative assessment of patient activation may help identify patients at risk of poor outcomes.

Vaccination efficacy in patients with chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is a disorder of mature malignant B cells with multiple elements of immune dysfunction. Infections are common in CLL patients due to complex immunodeficiency. Vaccines are used as preventative measures for common diseases including influenza, pneumococcus, tetanus/diphtheria and shingles in the general population. Vaccines are utilized to mitigate this risk, although there have been some concerns regarding the efficacy of vaccines in the CLL population due to the inherent complex immune dysfunction associated with the disease. In this review, we describe the clinical and laboratory indicators for efficacy of the vaccines in the CLL population (including COVID-19, influenza, pneumonia, herpes zoster, and tetanus) and discuss immunization recommendations for patients with CLL.

Interval Time of at Least 6 Weeks Between Bilateral Total Knee Arthroplasties is Associated With Decreased Postoperative Complications

BACKGROUND

Staged, bilateral total knee arthroplasty (TKA) has an increased risk of complications if the second procedure is performed before physiologic recovery from the first. The aims of this study were to 1) determine whether there is a time-dependent relationship between TKA staging and rates of revisions and complications and 2) identify data-driven time intervals that reduce risk of revisions and complications.

METHODS

Data were collected from a national insurance database from 2015 to 2018. Staged intervals were initially assessed using fixed 6-week intervals. Stratum-specific likelihood ratio analyses were subsequently conducted to observe data-driven staging thresholds. Bivariate and multivariable regression analyses were conducted to determine the associations between the time intervals and 2-year rates of revision surgery and 90-day major complications. We included 25,527 patients undergoing staged bilateral TKA.

RESULTS

In comparison to the shortest fixed time interval (1-6 weeks), as the staging interval increased the odds of 2-year all-cause revision and 90-day major complications significantly decreased (P < .05 for all). Stratum-specific likelihood ratio analysis identified 3 data-driven staging categories 1-5, 6-17, and 18-24 weeks that maximized the difference in both 2-year rates of revision and 90-day major complications.

CONCLUSION

Our data showed a time-dependent relationship between the timing of TKA stages and complications. If staging is considered, a delayed interval of at least 6 weeks between procedures may significantly reduce revision and major complications.

LEVEL OF EVIDENCE

Level III Therapeutic Study.

Osteoradionecrosis versus Cancer Recurrence: An Unresolved Clinical Dilemma

INTRODUCTION

Osteoradionecrosis is a rare and debilitating risk of definitive chemoradiotherapy for head and neck squamous cell carcinoma. It is difficult to distinguish between osteoradionecrosis and recurrent or progressive disease, as clinical and radiologic features may be similar. Our aim was to compare the clinical presentation and radiologic features of osteonecrosis with those of recurrent or progressive cancer.

METHODS

We conducted a single-center case series of 19 patients with head and neck squamous cell carcinoma diagnosed between 2011 and 2019 who subsequently developed clinical and/or radiological suspicion of osteoradionecrosis. The population was a referred sample from head and neck cancer physicians at Northwell Health Cancer Institute. Clinician notes and imaging reports were reviewed to assign a final diagnosis of either cancer, osteonecrosis, or indeterminate.

RESULTS

No differences were found in the clinical presentation or radiologic features between groups. Median time between treatment and development of symptoms was longer in patients with a final diagnosis of osteoradionecrosis than recurrent or progressive disease (5 vs. 3 months), but this difference was not statistically significant. Radiation dose and type were not associated with diagnosis. Mean standard uptake value maximums on positron emission tomography/computed tomography were significantly higher in the cancer group (median 14.8 vs. 9.1, p < 0.0152). At 1 year after first suspicion of osteoradionecrosis, 100% of osteoradionecrosis patients were alive, versus 28.6% of cancer patients.

DISCUSSION/CONCLUSION

There is significant overlap in clinical and radiologic features of osteoradionecrosis and cancer. Standard uptake maximums may be helpful in predicting diagnosis. Occurrence of symptoms within 6 months of completing chemoradiotherapy should raise the concern for malignancy.

[A case of intramuscular injection of methomyl poisoning]

Methomyl is a carbamate insecticide widely used in pesticides. Most of the poisoning methods are through digestive tract, respiratory tract and skin contact. At present, there is no report of poisoning caused by intramuscular injection. A case of poisoning caused by intramuscular injection of methomyl was analyzed retrospectively. About 4 minutes later, cholinergic crisis and central inhibition occurred. Venovenous-Extracorporeal Membrane Oxygenation (VV-ECMO) and atropine were given quickly. Finally, the patient was successfully rescued and had a good prognosis. After intramuscular injection of methomyl, cholinergic crisis can occur rapidly, and the onset rate is significantly faster than that of digestive tract, respiratory tract and skin contact.

A Novel Method for Stratification of Major Complication Risk Using Body Mass Index Thresholds for Patients Undergoing Total Hip Arthroplasty: A National Cohort of 224,413 Patients

INTRODUCTION

Elevated body mass index (BMI) is associated with complications following Total Hip Arthroplasty (THA). Since obese individuals are almost 10 times more likely to require THA compared to non-obese individuals, we need to understand the risk-benefit continuum while considering THA in obese patients. We aimed to determine data-driven thresholds for BMI at which the risk of major complications following THA increases significantly.

METHODS

Patients were identified in a national database who underwent primary THA from 2010 to 2020. BMI thresholds were identified using the stratum-specific likelihood ratio (SSLR) methodology, which is an adaptive technique that allows for identification of BMI cut-offs, at which the risk of major complications is increased significantly . BMI cutoffs identified using SSLR were used to create a logistic regression model.

RESULTS

A total of 224,413 patients were identified with a mean age of 66 ± 10, BMI 32 ± 6.7, and 7,186 (3%) sustained a major complication. BMI thresholds were defined as 19-31, 32-37, 38-49 and 50+. Overall, the absolute risk of major complications increased from 2.9% in the lowest BMI strata to 7.5% in the highest BMI strata. Compared to patients with a BMI between 19-31, the odds of sustaining a major complication sequentially increased by 1.2, 1.6, and 2.5-times for patients in each higher BMI strata (all, P < .05).

CONCLUSIONS

We have identified BMI cutoffs using SSLR that categorizes patients into four categories of risk for major complications in a nationally representative patient sample. These thresholds can be used in the surgical decision-making process between patients and surgeons.

[Application of liquid biopsy in early screening and recurrence prediction of hepatocellular carcinoma]

The incidence and mortality of HCC in China account for approximately 50% of all cases worldwide. Low early diagnosis rate and high postoperative recurrence rate are two major causes for poor 5-year survival rate of HCC patients in China. At present, multiple problems such as low performance and compliance of screening technology and lack of effective markers for predicting postoperative recurrence, remain to be resolved. Due to the simplicity and accuracy, new molecular markers, such as liquid biopsy, are expected to serve as supplementary tools to traditional screening and early warning approaches, thereby realizing early detection and accurate treatment of HCC. In this article, research progress upon the clinical application of liquid biopsy in early screening and prediction of postoperative recurrence of HCC was reviewed, and prospects the future research.

Growing Racial Disparities in the Utilization of Adult Spinal Deformity Surgery: An Analysis of Trends From 2004 to 2014

STUDY DESIGN

Retrospective.

OBJECTIVE

The purpose of this study was to assess trends in utilization rates of adult spinal deformity (ASD) surgery, as well as perioperative surgical metrics between Black and White patients undergoing operative treatment for ASD in the United States.

SUMMARY OF BACKGROUND DATA

Racial disparities in access to care, complications, and surgical selection have been shown to exist in the field of spine surgery. However, there is a paucity of data concerning racial disparities in the management of ASD patients.

METHODS

Adult patients undergoing ASD surgery from 2004 to 2014 were identified in the nationwide inpatient sample (NIS). Utilization rates, major complications rates, and length of stay (LOS) for Black patients and White patients were trended over time. Utilization rates were reported per 1,000,000 people and determined using annual census data among subpopulations stratified by race. All reported complication rates and prolonged hospital stay rates are adjusted for Elixhauser Comorbidity Index, income quartile by zip code, and insurance payer status.

RESULTS

From 2004 to 2014, ASD utilization for Black patients increased from 24.0 to 50.9 per 1,000,000 people, whereas ASD utilization for White patients increased from 29.9 to 73.1 per 1,000,000 people, indicating a significant increase in racial disparities in ASD utilization (P-trend < 0.001). There were no significant differences in complication rates or rates of prolonged hospital stay between Black and White patients across the time period studied (P > 0.05 for both).

CONCLUSION

Although Black and White patients undergoing ASD surgery do not differ significantly in terms of postoperative complications and length of hospital stay, there is a growing disparity in utilization of ASD surgery between White and Black patients from 2004 to 2014 in the United States. There is need for continued focus on identifying ways to reduce racial disparities in surgical selection and perioperative management in spine deformity surgery.Level of Evidence: 3.

Increased Risk of Surgical-Site Infection and Need for Manipulation Under Anesthesia for Those Who Undergo Open Versus Arthroscopic Rotator Cuff Repair

Purpose

Methods

Results

Conclusions

Level of Evidence

[Progress in prevention and control of Nipah virus disease]

Nipah virus disease (NVD) is a newly emerged zoonosis with a case fatality rate of 40%-75%. NVD is a severe threat to human health and the development of livestock farming. NVD has become one of the emerging infectious diseases with great concern globally during more than 20 years. Nipah virus (NiV) is a pathogen for NVD, the natural host of which is Fruit bats of the Pteropodidae family. The clinical spectrum of NiV infection is broad, including asymptomatic infection, acute respiratory infection, fatal encephalitis, and even death. Since NiV was first identified in Malaysia in 1999, it has been prevalent mainly in Southeast Asia and South Asia. NiV is primarily transmitted to humans through bat-pig-human, contaminated food. Currently, there are no specific therapeutic drugs and vaccines for NVD. Although there are no cases of NVD reported in China, which has close personnel and trade exchanges with major NVD-endemic countries, and NiV antibody has also been detected in relevant bats. There is a potential risk of importing NVD and domestic outbreaks in the future in this country. This paper provides a systematic review of the research progress in the prevention and control of NVD etiology, epidemiology, clinical manifestations and laboratory diagnosis to help relevant staff to understand NVD more comprehensively and systematically.

The BTK Safety Score: A Novel Scoring System for Risk Stratifying Patients Undergoing Simultaneous Bilateral Total Knee Arthroplasty

Selection of appropriate candidates for simultaneous bilateral total knee arthroplasty (si-BTKA) is crucial for minimizing postoperative complications. The aim of this study was to develop a scoring system for identifying patients who may be appropriate for si-BTKA. Patients who underwent si-BTKA were identified in the National Surgical Quality Improvement Program database. Patients who experienced a major 30-day complication were identified as high-risk patients for si-BTKA who potentially would have benefitted from staged bilateral total knee arthroplasty. Major complications included deep wound infection, pneumonia, renal insufficiency or failure, cerebrovascular accident, cardiac arrest, myocardial infarction, pulmonary embolism, sepsis, or death. The predictive model was trained using randomly split 70% of the dataset and validated on the remaining 30%. The scoring system was compared against the American Society of Anesthesiologists (ASA) score, the Charlson Comorbidity Index (CCI), and legacy risk-stratification measures, using area under the curve (AUC) statistic. Total 4,630 patients undergoing si-BTKA were included in our cohort. In our model, patients are assigned points based on the following risk factors: +1 for age ≥ 75, +2 for age ≥ 82, +1 for body mass index (BMI) ≥ 34, +2 for BMI ≥ 42, +1 for hypertension requiring medication, +1 for pulmonary disease (chronic obstructive pulmonary disease or dyspnea), and +3 for end-stage renal disease. The scoring system exhibited an AUC of 0.816, which was significantly higher than the AUC of ASA (0.545; p < 0.001) and CCI (0.599; p < 0.001). The BTK Safety Score developed and validated in our study can be used by surgeons and perioperative teams to risk stratify patients undergoing si-BTKA. Future work is needed to assess this scoring system's ability to predict long-term functional outcomes.

Does Prior Lumbar Fusion Influence Dislocation Risk in Hip Arthroplasty Performed for Femoral Neck Fracture?

BACKGROUND

Immobility of the lumbar spine predicts instability following elective total hip arthroplasty (THA). The purpose of this study is to determine how prior lumbar fusion (LF) influenced dislocation rates and revision rates for patients undergoing THA or hemiarthroplasty (HA) for femoral neck fracture (FNF).

METHODS

A retrospective cohort analysis was conducted utilizing the PearlDiver database from 2010 to 2018. Patients who underwent arthroplasty for FNF were identified based on history of LF and whether they underwent THA or HA. Univariate and multivariate analyses were performed.

RESULTS

A total of 328 patients with prior LF and FNF who underwent THA were at increased risk for 1-year dislocation (odds ratio [OR] 2.19, P < .001) and 2-year revision (OR 2.22, P < .001) compared to 14,217 patients without LF. The 461 patients with prior LF and FNF who underwent HA were at increased risk for dislocation (OR 2.22, P < .001) compared to 42,327 patients without LF. Patients with prior LF and FNF who underwent THA had higher rates of revision than patients with prior LF who underwent HA for FNF (OR 2.11, P < .001). In patients with prior LF and FNF, THA was associated with significantly increased risk for dislocation (OR 3.07, P < .001) and revision (OR 2.53, P < .001) compared to THA performed for osteoarthritis.

CONCLUSION

Patients with prior LF who sustained an FNF and underwent THA or HA were at increased risk for early dislocation and revision compared to those without prior LF. This risk of dislocation and revision is even greater than that observed in patients with prior LF who underwent THA for osteoarthritis.

LEVEL OF EVIDENCE

Level III.

Scoliosis in Pediatric Patients With Acute Flaccid Myelitis

BACKGROUND

Acute flaccid myelitis (AFM) is an anterior horn disorder that manifests as rapid onset muscle weakness or paralysis. Development of scoliosis in pediatric AFM patients has been anecdotally reported, but associated risk factors or incidence have yet to be determined.

METHODS

Pediatric AFM patients treated over a 10-year period at a tertiary care center were identified. Patients were considered to have scoliosis if there was radiographic evidence of coronal curvature ≥15 degrees. Number of limbs affected, independent ambulation and head control, ventilator requirement at initial admission, and long-term ventilatory support (≥1 year) were recorded. Muscle strength and functional status were assessed by manual muscle testing (MMT) and Physical Abilities and Mobility Scale (PAMS), respectively. Areas of spinal cord lesion on initial MRI were recorded. Bivariate analyses were performed, with alpha set to 0.05.

RESULTS

Fifty-six AFM patients (27 scoliosis, 29 no scoliosis) were identified. Mean time from AFM presentation to scoliosis diagnosis was 0.93 years. Mean major Cobb angle at first radiograph was 31.7 ± 14.3 degrees. Lack of independent ambulation, ventilator dependence at time of admission or long term, number of limbs affected, and decreased MMT and PAMS scores were more common in patients who developed scoliosis (all, p < .05). Patients who developed scoliosis had more extensive thoracic spinal cord involvement on initial MRI (p = .03).

CONCLUSION

AFM patients who develop scoliosis are more likely to be ventilator dependent, lack independent ambulation, and have more extensive thoracic SCI.

Do Disparities in Wait Times to Operative Fixation for Pathologic Fractures of the Long Bones and 30-day Complications Exist Between Black and White Patients? A Study Using the NSQIP Database

BACKGROUND

Racial disparities in outcomes after orthopaedic surgery have been well-documented in the fields of arthroplasty, trauma, and spine surgery; however, little research has assessed differences in outcomes after surgery for oncologic musculoskeletal disease. If racial disparities exist in the treatment of patients with pathologic long bone fractures, then they should be identified and addressed to promote equity in patient care.

QUESTIONS/PURPOSES

(1) How do wait times between hospital admission and operative fixation for pathologic fractures of long bones differ between Black and non-Hispanic white patients, after controlling for confounding variables using propensity score matching? (2) How does the proportion of patients with 30-day postoperative complication differ between these groups after controlling for confounding variables using propensity score matching?

METHODS

Using the National Surgical Quality Improvement Program database, we analyzed 828 patients who underwent fixation for pathologic fractures from 2012 to 2018. This database not only provides a large enough sample of pathologic long bone fracture patients to conduct the present study, but also it contains variables such as time from hospitalization to surgery that other national databases do not. After excluding patients with incomplete data (4% of the initial cohort), 775 patients were grouped by self-reported race as Black (12% [94]) or white (88% [681]). Propensity score matching using a 1:1 nearest-neighbor match was then used to match 94 Black patients with 94 white patients according to age, gender, BMI, American Society of Anesthesiologists physical status classification, anemia, endstage renal disease, independence in performing activities of daily living, congestive heart failure, and pulmonary disease. The primary outcome of interest was the number of days between hospital admission and operative fixation, which we assessed using a Poisson regression and report as an incidence risk ratio. The secondary outcomes were the occurrences of major 30-day postoperative adverse events (failure to wean off mechanical ventilation, cerebrovascular events, renal failure, cardiovascular events, reoperation, death), minor 30-day adverse events (reintubation, wound complications, pneumonia, and thromboembolic events), and any 30-day adverse events (defined as the pooling of all adverse events, including readmissions). These outcomes were analyzed using a bivariate analysis and logistic regression with robust estimates of variance and are reported as odds ratios. Because any results on disparities rely on rigorous control of other baseline demographics, we performed this multivariable approach to ensure we were controlling for confounding variables as much as possible.

RESULTS

After controlling for potentially confounding variables such as age and gender, we found that Black patients had a longer mean wait time (incidence risk ratio 1.5 [95% CI 1.1 to 2.1]; p = 0.01) than white patients. After controlling for confounding variables, Black patients also had greater odds of having any postoperative adverse event (OR 2.1 [95% CI 1.1 to 3.8]; p = 0.02), including readmission (OR 3.3 [95% CI 1.5 to 7.6]; p = 0.004).

CONCLUSION

The racial disparities in pathologic long bone fracture care found in our study may be attributed to fundamental racial biases, as well as systemic socioeconomic disparities in the US healthcare system. Identifying and eliminating the racial, socioeconomic, and sociocultural biases that drive these disparities would improve care for patients with orthopaedic oncologic conditions. One possible way to reduce these disparities would be to implement standardized surgical care pathways for pathological long bone fractures across different institutions to minimize variation in important aspects of care, such as time to surgical fixation. Further insight is needed on the types of standardized care pathways and the implementation mechanisms that are most effective.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Neural network prediction of 30-day mortality following primary total hip arthroplasty

Purpose

The purpose is to utilize an artificial neural network (ANN) model to determine the most important variables in predicting mortality following total hip arthroplasty (THA).

Methods

Patients that underwent primary THA were included from a national database. Demographic, preoperative, and intraoperative variables were analyzed based on their contribution to 30-day mortality with the use of an ANN model.

Results

The five most important factors in predicting mortality following THA were preoperative international normalized ratio, age, body mass index, operative time, and preoperative hematocrit.

Conclusion

ANN modeling represents a novel approach to determining perioperative factors that predict mortality following THA.

COVID-19 Significantly Impacted Hospital Length of Stay and Discharge Patterns for Adult Spinal Deformity Patients

STUDY DESIGN

Retrospective review.

OBJECTIVE

The primary aim was to compare length of stay (LOS) and discharge disposition of adult spinal deformity (ASD) patients undergoing surgery before and during the pandemic. Secondary aims were to compare the rates of 30-day complications, reoperations, readmissions, and unplanned emergency department (ED) visits.

SUMMARY OF BACKGROUND DATA

ASD patients often require extended LOS and non-routine discharge. Given resource limitations during the Coronavirus Disease 2019 (COVID-19) pandemic and caution regarding hospital stays, surgeons modified standard postoperative protocols to minimize patient exposure.

METHODS

We identified all patients who underwent elective thoracolumbar ASD surgery with more than or equal to five levels fusion at a tertiary care center during two distinct time intervals: July to December 2019 (Pre-COVID, N = 60) and July to December 2020 (During-COVID, N = 57). Outcome measures included LOS and discharge disposition (home vs. non-home), as well as 30-day major complications, reoperations, readmissions, and ED visits. Regression analyses controlled for demographic and surgical factors.

RESULTS

Patients who underwent ASD surgery during the pandemic were younger (61 vs. 67 yrs) and had longer fusion constructs (nine vs. eight levels) compared with before the pandemic (P < 0.05 for both). On bivariate analysis, patients undergoing surgery during the pandemic had shorter LOS (6 vs. 9 days) and were more likely to be discharged home (70% vs. 28%) (P < 0.05 for both). After controlling for age and levels fused on multivariable regression, patients who had surgery during the pandemic had shorter LOS (IRR = 0.83, P = 0.015) and greater odds of home discharge (odds ratios [OR] = 7.2, P < 0.001). Notably, there were no differences in major complications, reoperations, readmissions, or ED visits between the two groups.

CONCLUSION

During the COVID-19 pandemic, LOS for patients undergoing thoracolumbar ASD surgery decreased, and more patients were discharged home without adversely affecting complication or readmission rates. Lessons learned during the pandemic may help improve resource utilization without negatively influencing short-term outcomes.Level of Evidence: 3.

[Analysis of characteristics of collateral circulation pathways in dizziness patients caused by severe bilateral vertebral artery stenosis/occlusion]

The clinical data of 47 patients [41 males, 6 females, aged (62±7) years] treated at the Department of Neurology of the Sixth Medical Center of PLA General Hospital from October 2018 to October 2020 who were diagnosed with severe bilateral vertebral artery stenosis/occlusion through Digital Subtraction Angiography (DSA) were retrospectively collected, and the characteristics of the compensatory pathways of collateral circulation were determined. Results showed that there were 8 intracranial and extracranial compensatory pathways, with posterior communicating artery as the major type (21 cases) for intracranial ones and deep carotid artery as the major type (16 cases) for extracranial ones. As the establishment of the compensatory pathway is closely related to the lesion site, DSA assessment for patients with severe bilateral vertebral artery stenosis/occlusion is helpful for clinicians to make judgement on prognosis of patients and choose individualized treatment plans.

Preoperative Hyponatremia is an Independent Risk Factor for Prolonged Hospital Stay Following Anterior Cervical Discectomy and Fusion

OBJECTIVE

To determine the effects of preoperative hyponatremia on short-term postoperative complications and healthcare utilization (length of stay, readmissions) following anterior cervical fusion and discectomy (ACDF).

METHODS

Patients who underwent ACDF were identified in the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database. Patients who had revision surgery, trauma, vertebral malignancy, or infection were excluded. Eunatremia was defined as sodium (Na) level between 135 and 145 mEq/L, whereas hyponatremia was defined as Na < 135 mEq/L. Preoperatively hyponatremic patients were matched 1:1 with eunatremic patients using propensity-score matching based upon age, gender, American Society of Anesthesiology (ASA) score, and baseline comorbidities. Minor adverse events included superficial infection, dehiscence, urinary tract infection, pneumonia, and renal insufficiency or failure. Serious adverse events included deep wound infection, reintubation, pulmonary embolism, cerebrovascular accident, cardiac arrest, deep vein thrombosis, sepsis, return to operating room, and death within 30 days. Complications were analyzed using bivariate and logistic analysis with significance set at p<0.05.

RESULTS

Of the 9,094 patients undergoing ACDF, 3.64% (331 patients) were preoperatively hyponatremic. Preoperative hyponatremia was an independent risk factor for postoperative pneumonia following ACDF (OR=4.47; p=0.020) as well as extended length of hospital stay greater than one standard deviation above the mean (OR=1.71; p=0.042). Preoperative hyponatremia was an independent risk factor for having a serious adverse event (OR=2.40; p=0.005), as well as any adverse event (OR=2.44; p=0.009).

CONCLUSION

Preoperative hyponatremia is an independent risk factor for pneumonia and prolonged length of stay following ACDF.

Trends and risk factors for opioid administration for non-emergent lower back pain

BACKGROUND

Non-emergent low-back pain (LBP) is one of the most prevalent presenting complaints to the emergency department (ED) and has been shown to contribute to overcrowding in the ED as well as diverting attention away from more serious complaints. There has been an increasing focus in current literature regarding ED admission and opioid prescriptions for general complaints of pain, however, there is limited data concerning the trends over the last decade in ED admissions for non-emergent LBP as well as any subsequent opioid prescriptions by the ED for this complaint.

AIM

To determine trends in non-emergent ED visits for back pain; annual trends in opioid administration for patients presenting to the ED for back pain; and factors associated with receiving an opioid-based medication for non-emergent LBP in the ED

METHODS

Patients presenting to the ED for non-emergent LBP from 2010 to 2017 were retrospectively identified from the National Hospital Ambulatory Medical Care Survey database. The “year” variable was transformed to two-year intervals, and a weighted survey analysis was conducted utilizing the weighted variables to generate incidence estimates. Bivariate statistics were used to assess differences in count data, and logistic regression was performed to identify factors associated with patients being discharged from the ED with narcotics. Statistical significance was set to a P value of 0.05.

RESULTS

Out of a total of 41658475 total ED visits, 3.8% (7726) met our inclusion and exclusion criteria. There was a decrease in the rates of non-emergent back pain to the ED from 4.05% of all cases during 2010 and 2011 to 3.56% during 2016 and 2017. The most common opioids prescribed over the period included hydrocodone-based medications (49.1%) and tramadol-based medications (16.9), with the combination of all other opioid types contributing to 35.7% of total opioids prescribed. Factors significantly associated with being prescribed narcotics included age over 43.84-years-old, higher income, private insurance, the obtainment of radiographic imaging in the ED, and region of the United States (all, P < 0.05). Emergency departments located in the Midwest [odds ratio (OR): 2.42, P < 0.001], South (OR: 2.35, < 0.001), and West (OR: 2.57, P < 0.001) were more likely to prescribe opioid-based medications for non-emergent LBP compared to EDs in the Northeast.

CONCLUSION

From 2010 to 2017, there was a significant decrease in the number of non-emergent LBP ED visits, as well as a decrease in opioids prescribed at these visits. These findings may be attributed to the increased focus and regulatory guidelines on opioid prescription practices at both the federal and state levels. Since non-emergent LBP is still a highly common ED presentation, conclusions drawn from opioid prescription practices within this cohort is necessary for limiting unnecessary ED opioid prescriptions.

Surgically Managed Malakoplakia of the Spine: A Case Report

CASE

A 66-year-old woman with polymyositis and recurrent urinary tract infections presented with lumbar pain and progressive lower extremity neuropathy. Imaging showed lytic destruction of the vertebral bone from L2 to L4 with extension into adjacent musculature. Histological examination demonstrated Michaelis-Gutmann bodies consistent with malakoplakia. The patient underwent revision T12-sacrum posterior fusion, L2-5 laminectomy, and anterior L3-4 corpectomy, followed by L2-4 anterior stabilization and a 6-week course of ceftriaxone. At 3 months postoperatively, she was asymptomatic without recurrence.

CONCLUSION

Malakoplakia of bone should be considered in the differential diagnosis of lytic bone lesions and can be effectively treated with surgical debulking with penetrative antibiotics.

[Cost-effectiveness of anti-tumor associated antigen autoantibody screening for hepatocellular carcinoma in the population with chronic hepatitis B-related cirrhosis]

Objective: To evaluate the cost-effectiveness of anti-tumor associated antigen autoantibody (TAAb) for hepatocellular carcinoma (HCC) screening in cirrhosis population with chronic hepatitis B (CHB). Methods: A simulated cohort of 40-year-old patients with CHB cirrhosis was established with a sample size of 10 000. Using TAAb screening alone or TAAb and AFP screening in parallel (TAAb + AFP) as the research strategy, and liver ultrasound and AFP screening in parallel (liver ultrasound + AFP) as the control strategy, the decision analysis Markov model was constructed and the model validity was evaluated. The 6-month cycle was simulated using TreeAge Pro 2020 software. Cost and quality-adjusted life years (QALY) were calculated. Incremental cost-effectiveness ratio (ICER) was used to compare the two strategies, and sensitivity analysis was used to evaluate the uncertainty of results. Results: The Markov model had a total of 11 outcomes, of which 7 were natural outcomes and 4 wereclinical intervention outcomes, and the goodness of fit was 0.969. The lifetime screening cost of TAAb+AFP strategy for HCC screening was 249 612 yuan/case, and the QALY per capita was 7.704 years. Compared with liver ultrasound +AFP strategy (247 805 yuan/case), the total health cost increased by 1 807 yuan/case, and the QALY obtained was 0.014. The ICER was 127 635 yuan /QALY. When the TAAb screening fee was higher than 889.552 yuan, or the discount rate was higher than 0.068, or the antiviral treatment compliance was lower than 45.1%, ICER > 212 676 yuan /QALY. When the single TAAb screening fee was 400-600 yuan, the TAAB+AFP strategy had cost effective value. When the willingness to pay was 70 892, 141 784 and 212 676 yuan /QALY, the probability of cost-effectiveness of TAAb+AFP strategy was 70.6%, 75.3% and 77.8%, respectively. Conclusion: It is cost-effective to use TAAb+AFP for early screening of liver cancer in Chinese population with CHB cirrhosis.

[One case report of pneumoconiosis in porcelain teeth workers]

Porcelain tooth technology is widely used in the treatment of oral diseases, but there are few reports on the possible occupational hazard factors in the process of porcelain tooth production. Porcelain teeth production will produced a large amount of silica dust and metal dust during the grinding process. The technical workers who have been engaged in this work for a long time are very prone to pneumoconiosis due to their poor personal protection awareness. This paper analyzed the clinical data of a pneumoconiosis patient engaged in porcelain tooth making, and analyzed the possible occupational hazard factors in the process of porcelain teeth production, so as to improve the understanding of relevant enterprises, technical workers and medical personnel on the disease and reduce the risk of porcelain teeth production workers suffering from pneumoconiosis.

Artificial neural network prediction of same-day discharge following primary total knee arthroplasty based on preoperative and intraoperative variables

AIMS

This study used an artificial neural network (ANN) model to determine the most important pre- and perioperative variables to predict same-day discharge in patients undergoing total knee arthroplasty (TKA).

METHODS

Data for this study were collected from the National Surgery Quality Improvement Program (NSQIP) database from the year 2018. Patients who received a primary, elective, unilateral TKA with a diagnosis of primary osteoarthritis were included. Demographic, preoperative, and intraoperative variables were analyzed. The ANN model was compared to a logistic regression model, which is a conventional machine-learning algorithm. Variables collected from 28,742 patients were analyzed based on their contribution to hospital length of stay.

RESULTS

The predictability of the ANN model, area under the curve (AUC) = 0.801, was similar to the logistic regression model (AUC = 0.796) and identified certain variables as important factors to predict same-day discharge. The ten most important factors favouring same-day discharge in the ANN model include preoperative sodium, preoperative international normalized ratio, BMI, age, anaesthesia type, operating time, dyspnoea status, functional status, race, anaemia status, and chronic obstructive pulmonary disease (COPD). Six of these variables were also found to be significant on logistic regression analysis.

CONCLUSION

Both ANN modelling and logistic regression analysis revealed clinically important factors in predicting patients who can undergo safely undergo same-day discharge from an outpatient TKA. The ANN model provides a beneficial approach to help determine which perioperative factors can predict same-day discharge as of 2018 perioperative recovery protocols. Cite this article: Bone Joint J 2021;103-B(8):1358-1366.

Conversion total knee arthroplasty: A case complexity between primary and revision total knee arthroplasty

BACKGROUND

Conversion total knee arthroplasty (TKA) may represent a more complex procedure compared with primary TKA. The purpose of this study was to compare 30-day complications between conversion TKA and primary, non-conversion TKA as well as between conversion TKA and revision TKA on a national scale using a multi-center surgical registry.

METHODS

Adult patients undergoing conversion TKA from 2006 to 2018 were identified in the National Surgical Quality Improvement Program database and were compared with patients who underwent primary TKA and aseptic revision TKA. In this analysis, 30-day complications were assessed. Bivariate analyses, including chi-squared and analysis of variance, and multivariate logistic regressions were performed.

RESULTS

Of 299,065 total patients undergoing knee arthroplasty, 1,310 (0.4%) underwent conversion TKA, 275,470 (92.1%) underwent primary TKA, and 22,285 (7.5%) underwent revision TKA. Following adjustment, patients who underwent conversion TKA were more likely to have increased risks of any complications (P < 0.001), mortality (P = 0.021), wound complications (P < 0.001), cardiac issues (P = 0.018), bleeding requiring transfusion (P < 0.001), and reoperation (P = 0.002) relative to primary TKA patients. Compared with patients who underwent revision TKA, conversion TKA patients were less likely to have septic complications (P = 0.009).

CONCLUSION

Conversion TKA is associated with significantly higher rates of complications compared with primary, non-conversion TKA, but less risk of sepsis compared with revision TKA. Because current reimbursement classifications do not account for the case complexity of a conversion TKA, new classifications should be implemented with reimbursements for conversion TKA approximating reimbursements for revision TKA.

[Collateral circulation pathway in patients with basilar artery occlusion/severe stenosis: a single-center case series]

Objective: To investigate the collateral circulation compensation model in patients with favorable prognosis of basilar artery occlusion/severe stenosis treated with drugs or endovascular therapy. Methods: Clinical data of patients with basilar artery occlusion/severe stenosis and good clinical outcome were retrospectively collected in the Department of Neurology, Sixth Medical Center of PLA General Hospital from January 2019 to January 2020. They were divided into intensive drug therapy group and combined endovascular therapy group. The number and ways of collateral compensation pathway described by digital substraction angiography (DSA) were analyzed, and the characteristics of the collateral compensation model were summarized. SPSS22.0 software was used for statistical analysis, and the constituent ratio (%) was used for statistical description of the enumeration data. Results: A total of 32 eligible patients were included, including 27 males and 5 females, with an average age 45-76 (59±10) years. The compensation model included posterior communicating artery-posterior cerebral artery (13 cases, 40.6%), posterior communicating artery-posterior cerebral artery-basilar artery (10 cases, 31.2%), cerebellar artery-anastomotic branches of superior cerebellar artery (8 cases, 25.0%), anterior choroid artery-anastomotic branches of posterior choroid artery (2 cases, 6.2%), collateral circulation not established (11 cases, 34.4%).In drug treatment group, collateral compensation was found in the majority (14/15), with mainly posterior communicating artery (10/14).Most patients in combined treatment group did not develop collateral compensation (10/17), anastomotic branches of PICA-SCA were the main routes (6/7). Conclusion: In patients with basilar artery occlusion/severe stenosis, favorable clinical outcome can be achieved in both groups of patients treated with intensive drug therapy or endovascular therapy.

The Impact of the COVID-19 Pandemic on Elective Inpatient Surgical Admissions: Evidence From Maryland

BACKGROUND

The COVID-19 pandemic led to large-scale cancellation and deferral of elective surgeries. We quantified volume declines, and subsequent recoveries, across all hospitals in Maryland.

MATERIALS AND METHODS

Data on elective inpatient surgical volumes were assembled from the Maryland Health Service Cost Review Commission for years 2019-2020. The data covered all hospitals in the state. We compared the volume of elective inpatient surgeries in the second (Q2) and fourth quarters (Q4) of 2020 to those same quarters in 2019. Analysis was stratified by patient, hospital, and service characteristics.

RESULTS

Surgical volumes were 55.8% lower in 2020 Q2 than in 2019 Q2. Differences were largest for orthopedic surgeries (74.3% decline), those on Medicare (61.4%), and in urban hospitals (57.3%). By 2020 Q4, volumes for most service lines were within 15% of volumes in 2019 Q4. Orthopedic surgery remained most affected (44.5% below levels in 2019 Q4) and Plastic Surgery (21.9% lower).

CONCLUSIONS

COVID-19 led to large volume declines across hospitals in Maryland followed by a partial recovery. We observed large variability, particularly across service lines. These results can help contextualize case-specific experiences and inform research studying potential health effects of these delays and cancellations.

Chronicling the effect of COVID-19 on orthopedic literature

Background

The novel coronavirus disease (COVID-19) has had a significant impact on orthopedic surgery practice, but there has been little investigation of the effects of COVID-19 on the orthopedic surgery literature. Additionally, because orthopedic research plays a vital role in physician education, changes to the characteristics and content of published literature can have lasting impacts on future teaching and learning. This paper represents the first known analysis of the COVID-19 pandemic's impact on peer-reviewed articles published in orthopedic surgery journals.

Methods

The 20 orthopedic journals with the highest impact factors in 2019, according to the Journal Citation Reports, were included in this study. Using PubMed and COVID-19 related keywords as well as manual screening, a final count of 199 articles were assessed for this study and subsequently sorted by country of origin, orthopedic subspecialty, article type, and general theme. Kruskal Wallis and Pearson's Chi-squared tests were used to analyze continuous and categorical variables, respectively.

Results

Fourteen journals published articles relating to COVID-19, representing 26 countries with the United States (37%) and United Kingdom (13%) publishing the greatest proportion of all COVID-19 articles. Sixty percent of publications discussed COVID-19's impact on the overall field of orthopedic surgery, with the remainder focusing on specific subspecialties. Forty-seven percent of publications were original research articles while 46% were editorials or commentaries. The median time to publication for all COVID-19 related articles was 24.5 days, compared to the 129 days reported for orthopedic journals prior to the COVID-19 pandemic (p < 0.001). In the first 100 articles published, 49% (n = 49) originated exclusively from United States institutions, whereas only 25% (n = 25) of the next ninety-nine articles had US-only institutions (p < 0.001).

Conclusions

The COVID-19 pandemic has significantly impacted the characteristics, content, and time to publication of the orthopedic surgery literature. The data and ideas presented in this paper should help streamline future, formal analysis on the lasting implications of COVID-19 on orthopedic surgery practice, teaching, and learning.

Severe acquired haemophilia associated with asymptomatic SARS-CoV-2 infection

A 65-year-old man presented with symptoms of severe subcutaneous bleeding in his arm, which led to compartment syndrome requiring fasciotomy and massive blood transfusion protocol. Medical history was significant for history of autoimmune thyroid disease. Workup revealed elevated partial thromboplastin time, decreased factor VIII levels and elevated factor VIII inhibitor levels. He was worked up for causes of acquired haemophilia A and was found to have an elevated SARS-CoV-2 antibody level. Given his negative workup for other secondary aetiologies, we suspect that the cause of his haemophilia A was from his SARS-CoV-2 infection, which has been observed previously in various case reports.

Using Predictive Modeling and Supervised Machine Learning to Identify Patients at Risk for Venous Thromboembolism Following Posterior Lumbar Fusion

STUDY DESIGN

Retrospective review.

OBJECTIVE

To use predictive modeling and machine learning to identify patients at risk for venous thromboembolism (VTE) following posterior lumbar fusion (PLF) for degenerative spinal pathology.

METHODS

Patients undergoing single-level PLF in the inpatient setting were identified in the National Surgical Quality Improvement Program database. Our outcome measure of VTE included all patients who experienced a pulmonary embolism and/or deep venous thrombosis within 30-days of surgery. Two different methodologies were used to identify VTE risk: 1) a novel predictive model derived from multivariable logistic regression of significant risk factors, and 2) a tree-based extreme gradient boosting (XGBoost) algorithm using preoperative variables. The methods were compared against legacy risk-stratification measures: ASA and Charlson Comorbidity Index (CCI) using area-under-the-curve (AUC) statistic.

RESULTS

13, 500 patients who underwent single-level PLF met the study criteria. Of these, 0.95% had a VTE within 30-days of surgery. The 5 clinical variables found to be significant in the multivariable predictive model were: age > 65, obesity grade II or above, coronary artery disease, functional status, and prolonged operative time. The predictive model exhibited an AUC of 0.716, which was significantly higher than the AUCs of ASA and CCI (all, P < 0.001), and comparable to that of the XGBoost algorithm (P > 0.05).

CONCLUSION

Predictive analytics and machine learning can be leveraged to aid in identification of patients at risk of VTE following PLF. Surgeons and perioperative teams may find these tools useful to augment clinical decision making risk stratification tool.

Epidemiology and clinicopathological features of lung cancer in patients with prior history of breast cancer

Breast cancer is the most common malignancy in women, and lung cancer, the leading cause of cancer-related mortality in the United States, is the most common subsequent primary cancer among breast cancer survivors. In this review, we examine the risk factors that cause subsequent primary lung cancer after breast cancer (referred to herein as BCLC patients) as well as the prognostic factors that may affect survival. Notable clinicopathological features include patient characteristics such as age, smoking history, and the presence of EGFR or BRCA mutations, as well as factors related to the treatment of breast cancer such as radiation, surgery, chemotherapy, stage, anti-estrogen therapy, and ER/PR/HER2 status.

[New progress in the diagnosis and treatment of hepatocellular carcinoma: a decade of grinding sword]

Globally, hepatocellular carcinoma (HCC) is one of the most highly morbid, fatal, and malignant tumors, with a poor prognosis in advanced stage. In the past decade, new advances have been emerged in the field of HCC therapy, including surgery, ablation, transvascular intervention, external radiotherapy, and systemic therapy. Among them, systemic treatments, particularly targeted and immune checkpoint drugs have made outstanding progress, significantly improving the five-year survival rate of liver cancer patients. In addition, the management of liver cancer patients, especially the screening management and multidisciplinary collaborative diagnosis and treatment of high-risk populations, has significantly increased the early diagnosis rate and improved the overall treatment efficacy. Considering our country's condition and the development of existing treatment, the most effective strategy to reduce HCC mortality in the future is to accurately identify high-risk populations, increase the early diagnosis rate, and formulate personalized treatment strategies.

Convalescent plasma for COVID-19 complicated by ARDS due to TRALI

Convalescent plasma, which contains antibodies from recovered individuals, has been used as an effective treatment for infectious diseases in the past and is currently being used as a potential treatment option for COVID-19. Multiple studies have reported this treatment to be safe. We report a case of a patient who developed acute respiratory distress syndrome (ARDS) with features suggestive of transfusion-related acute lung injury after being treated with convalescent plasma for COVID-19. We emphasise the need to be aware of the potential risk of transfusion reactions and disease worsening with convalescent plasma administration and to weigh the risk and benefits of this therapy before administration to patients and propose that further study be done regarding the potential risks of convalescent plasma.

Abstract 220: Disease monitoring of mycosis fungoides via high throughput sequencing of CDR3

Background

High-throughput T-cell receptor sequencing (HTS) has been shown to be both sensitive and specific at diagnosing Mycosis Fungoides (MF); a sensitivity of 85% was achieved with superiority to TCRγ; PCR in detecting monoclonality and a specificity of 99.89% was achieved in detecting minimal residual disease, specifically Sezary Syndrome cells with superiority to flow cytometry. In this study, we look at the potential application of HTS as a method for monitoring treatment response in patients with MF.

Methods

We sequenced the CDR3 region of the T-cell receptor (TCR) subunit of T cells in the skin lesional tissue, as well as in pre- and post-treatment blood samples of 7 patients with late stage Mycosis Fungoides (stage IIB-IV). DNA and RNA were extracted from peripheral blood and skin samples. Library preparation followed the manufacturer's instructions (Illumina). The template DNA fragments of the constructed libraries were hybridized to the surface of Nimblegen sequence Capture chip and detected with Hiseq2000 platform. Raw data was analyzed and verified to obtain aberrantly expressed genes. A multiplex PCR system was used to amplify the specific CDR3 region. Distinct TCR CDR3 sequences were plotted on the basis of their frequency of appearance to generate the TCR “repertoire”. The malignant clonal TCR signature was determined by the highest frequency CDR3 sequence of the tumor cells from skin biopsy specimens and confirmed by pathological diagnosis. This malignant sequence was identified in pre-treatment blood and monitored in post-treatment blood. Further analysis of each patient's TCR repertoire allowed us to calculate a diversity index (Simpson's diversity index) for each patient's skin sample. Results of diversity index calculation was analyzed with unpaired T-test using GraphPad Prism version 7 (GraphPad Software, La Jolla, CA). All p-values were two-tailed, with a p&lt;0.05 considered statistically significant.

Results

Frequency of the identified malignant TCR clone remained high in the post-treatment blood samples of the patients with poor treatment response, while the number of TCR signature clones diminished in the post-treatment blood samples of the patients with good treatment response. Higher levels of diversity of TCR was also seen in the skin pre-treatment for good responders to treatment.

Conclusion

This study used HTS to identify malignant TCR signatures from skin biopsy specimens and to monitor the changes in blood samples in MF patients. The findings suggest that HTS is a potential ancillary blood test to monitor treatment response in MF patients by comparing the levels of the TCR signature before and after therapy. A greater diversity of T-cells in the skin may also predict a better treatment response in MF, as the presence of tumor infiltrating lymphocytes has been correlated with better outcomes in many different cancers.

Citation Format: Kevin Y. Wang, Tao Wang, Yuehua Liu, Christine Lian. Disease monitoring of mycosis fungoides via high throughput sequencing of CDR3 [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 220.