Predictors of Return to Emergency Department and Readmission Following Primary Elective Total Shoulder Arthroplasty.

Objectives: Returns to the Emergency Department (ED) and unplanned readmissions within 90 days of shoulder arthroplasty represent a significant financial burden to healthcare systems. Identifying the reasons and risk factors could potentially reduce their prevalence. Methods: A retrospective review of primary anatomic (aTSA) and reverse shoulder arthroplasty (rTSA) cases from January 2016 through August 2023 was performed. Demographic patient and surgical data, including age, diagnosis of anxiety or depression, body mass index (BMI), smoking status, age-adjusted Charlson Comorbidity Index (ACCI), modified 5-item fragility index (mFI-5), and hospital length of stay (LOS) was collected. Patient visits to the ED within 12 months prior to surgery were recorded. Predictors for return to the ED within 90 days postoperatively and any readmissions were determined. Results: There were 338 cases (167 aTSA and 171 rTSA), of which 225 (67%) were women. Patients with anxiety (OR=2.44, 95% CI 1.11-5.33; P=0.026), surgical postoperative complications (OR=3.22, 95% CI 1.36-7.58; P=0.008), ED visit within 3 months prior to surgery (OR=3.80, 95% CI 1.71-8.45; P=0.001), ED visit 3 to 6 months prior to surgery (OR=2.60, 95% CI 1.12-6.05; P=0.027), and ED visit 6 to 12 months prior to surgery (OR=2.12, 95% CI 1.02-4.41; P=0.045) were more likely to have ED visit within 90 days postoperatively. Patients with prior ipsilateral shoulder surgery (OR=3.32, 95% CI 1.21-9.09; P=0.02), surgical postoperative complications (OR=13.92, 95% CI 5.04-38.42; P<0.001), an ED visit within 3 to 6 months preoperatively (OR=8.47, 95% CI 2.84-25.27; P<0.001), and an mFI-5 ≥2 (OR=3.66, 95% CI 1.35-9.91; P=0.011) were more likely to be readmitted within 90 days. Conclusion: Patients who present to the ED within 12 months prior to shoulder arthroplasty, those with anxiety, those with surgical complications and those with higher fragility should be monitored closely during the early postoperative period to minimize returns to the ED and/or unplanned readmissions.

Comprehensive single cell transcriptomics analysis of murine osteosarcoma uncovers Skp2 function in metastasis, genomic instability and immune activation and reveals additional target pathways.

Osteosarcoma (OS) is the most common primary pediatric bone malignancy. One promising new therapeutic target is SKP2, encoding a substrate recognition factor of the SCF E3 ubiquitin ligase responsible for ubiquitination and proteasome degradation of substrate p27, thus driving cellular proliferation. We have shown previously that knockout of Skp2 in an immunocompetent transgenic mouse model of OS improved survival, drove apoptosis, and induced tumor inflammation. Here, we applied single-cell RNA-sequencing (scRNA-seq) to study primary OS tumors derived from Osx-Cre driven conditional knockout of Rb1 and Trp53. We showed that murine OS models recapitulate the tumor heterogeneity and microenvironment complexity observed in patient tumors. We further compared this model with OS models with functional disruption of Skp2: one with Skp2 knockout and the other with the Skp2-p27 interaction disrupted (resulting in p27 overexpression). We found reduction of T cell exhaustion and upregulation of interferon activation, along with evidence of replicative and endoplasmic reticulum-related stress in the Skp2 disruption models, and showed that interferon induction was correlated with improved survival in OS patients. Additionally, our scRNA-seq analysis uncovered decreased activities of metastasis-related gene signatures in the Skp2-disrupted OS, which we validated by observation of a strong reduction in lung metastasis in the Skp2 knockout mice. Finally, we report several potential mechanisms of escape from targeting Skp2 in OS, including upregulation of Myc targets, DNA copy number amplification and overexpression of alternative E3 ligase genes, and potential alternative lineage activation. These mechanistic insights into OS tumor biology and Skp2 function suggest novel targets for new, synergistic therapies, while the data and our comprehensive analysis may serve as a public resource for further big data-driven OS research.

Child Opportunity Index and Diagnosis of Developmental Dysplasia of the Hip: Insights From a Children's Hospital Serving Disadvantaged Communities.

INTRODUCTION: Initiation of Pavlik harness treatment for developmental dysplasia of the hip (DDH) by 6 to 7 weeks of age predicts a higher rate of success. Child Opportunity Index (COI) 2.0 is a single metric designed to measure resources and conditions affecting children's healthy development. This study investigates COI in relation to the timing of DDH diagnosis. METHODS: This is a retrospective cohort study on patients younger than 4 years diagnosed with DDH between 2016 and 2023, treated with a Pavlik harness, rigid hip abduction orthosis, and/or surgery. Demographic and clinical data were recorded, including date of first diagnostic imaging. Patients with syndromes, congenital anomalies, or neuromuscular disorders and those referred with an unknown date of first diagnostic imaging were excluded. A subgroup analysis of patients diagnosed at ≤6 weeks ("early") and >6 weeks ("late") was conducted. Statewide COI scores (total, three domains) and categorical quintile scores (very low, low, moderate, high, and very high) were recorded. RESULTS: A total of 115 patients were included: 90 female infants (78%), with a median age of 32 days at diagnostic imaging. No notable difference was observed between median age at diagnosis for study patients in low or very low quintiles and those in moderate, high, or very high quintiles for COI total or domains. "Early" and "late" diagnosis subgroups did not differ markedly by COI total or domains, nor insurance type, race, or ethnicity. Subgroups differed markedly by race and insurance status. DISCUSSION: In an urban children's hospital, COI did not differ markedly between patients diagnosed with DDH by ≤6 weeks and >6 weeks. This is the first study to pose this question on DDH in a population with predominantly low/very low COI scores and public insurance, which may lead to unexpected results. Replicating the study in a different setting could yield different results. LEVEL OF EVIDENCE: III.

Retrospective analysis of discordant results between histology and other clinical diagnostic tests on helicobacter pylori infection.

BACKGROUND: A reliable test is essential for diagnosing Helicobacter pylori (H. pylori) infection, and crucial for managing H. pylori-related diseases. Serving as an excellent method for detecting H. pylori infection, histologic examination is a test that clinicians heavily rely on, especially when complemented with immunohistochemistry (IHC). Additionally, other diagnostic tests for H. pylori, such as the rapid urease test (CLO test) and stool antigen test (SA), are also highly sensitive and specific. Typically, the results of histology and other tests align with each other. However, on rare occasions, discrepancy between histopathology and other H. pylori diagnostic tests occurs. AIM: To investigate the discordance between histology and other H. pylori tests, the underlying causes, and the impact on clinical management. METHODS: Pathology reports of gastric biopsies were retrieved spanning August 2013 and July 2018. Reports were included in the study only if there were other H. pylori tests within seven days of the biopsy. These additional tests include CLO test, SA, and H. pylori culture. Concordance between histopathology and other tests was determined based on the consistency of results. In instances where histology results were negative while other tests were positive, the slides were retrieved for re-assessment, and the clinical chart was reviewed. RESULTS: Of 1396 pathology reports were identified, each accompanied by one additional H. pylori test. The concordance rates in detecting H. pylori infection between biopsy and other tests did not exhibit significant differences based on the number of biopsy fragments. 117 discrepant cases were identified. Only 20 cases (9 with CLO test and 11 with SA) had negative biopsy but positive results in other tests. Four cases initially stained with Warthin-Starry turned out to be positive for H. pylori with subsequent IHC staining. Among the remaining 16 true discrepant cases, 10 patients were on proton pump inhibitors before the biopsy and/or other tests. Most patients underwent treatment, except for two who were untreated, and two patients who were lost to follow-up. CONCLUSION: There are rare discrepant cases with negative biopsy but positive in SA or CLO test. Various factors may contribute to this inconsistency. Most patients in such cases had undergone treatment.

Targeted inhibition of SCFSKP2 confers anti-tumor activities resulting in a survival benefit in osteosarcoma.

Osteosarcoma(OS) is a highly aggressive bone cancer for which treatment has remained essentially unchanged for decades. Although OS is characterized by extensive genomic heterogeneity and instability, RB1 and TP53 have been shown to be the most commonly inactivated tumor suppressors in OS. We previously generated a mouse model with a double knockout (DKO) of Rb1 and Trp53 within cells of the osteoblastic lineage, which largely recapitulates human OS with nearly complete penetrance. SKP2 is a repression target of pRb and serves as a substrate recruiting subunit of the SCFSKP2 complex. In addition, SKP2 plays a central role in regulating the cell cycle by ubiquitinating and promoting the degradation of p27. We previously reported the DKOAA transgenic model, which harbored a knock-in mutation in p27 that impaired its binding to SKP2. Here, we generated a novel p53-Rb1-SKP2 triple-knockout model (TKO) to examine SKP2 function and its potential as a therapeutic target in OS. First, we observed that OS tumorigenesis was significantly delayed in TKO mice and their overall survival was markedly improved. In addition, the loss of SKP2 also promoted an apoptotic microenvironment and reduced the stemness of DKO tumors. Furthermore, we found that small-molecule inhibitors of SKP2 exhibited anti-tumor activities in vivo and in OS organoids as well as synergistic effects when combined with a standard chemotherapeutic agent. Taken together, our results suggest that SKP2 inhibitors may reduce the stemness plasticity of OS and should be leveraged as next-generation adjuvants in this cancer.

Missed Short-term Follow-up After Arthroscopic Rotator Cuff Surgery: Analysis of Surgical and Demographic Factors.

INTRODUCTION: Few current studies have examined loss to follow-up after rotator cuff-related shoulder arthroscopy. Understanding the demographic and surgical factors for missed follow-up would help identify patients most at risk and potentially mitigate the onset of complications while maximizing clinical outcomes. METHODS: A retrospective review of consecutive rotator cuff arthroscopic procedures with a minimum of 12-month follow-up done by a single, fellowship-trained surgeon was undertaken from February 2016 through January 2022. Demographic patient and surgical data, including age, sex, marital status, self-identified race, and body mass index, were collected. Follow-up at ≤3, 6 weeks, 3, 6, and 12 months was determined. Patient-related and surgical predictors for missed short-term follow-up, defined as nonattendance at the 6 and 12-month postoperative visits, were identified. RESULTS: There were 449 cases included, of which 248 (55%) were women. The median age was 57 years (interquartile range [IQR], 51 to 62). Patients with commercial insurance (odds ratio [OR], 0.38; 95% confidence interval [CI], 0.23 to 0.64; P < 0.001) or workers' compensation (OR, 0.15; 95% CI, 0.05 to 0.43; P < 0.001) were less likely to miss the 6-month follow-up compared with patients with Medicare, whereas increased socioeconomic deprivation (OR, 0.86; 95% CI, 0.77 to 0.97, P = 0.015) was associated with decreased odds of missing that visit. Patients who missed the ≤3 weeks (OR, 1.77; 95% CI, 1.14 to 2.74, P = 0.010) and 3-month (OR, 8.55; 95% CI, 4.33 to 16.86; P < 0.001) follow-ups were more likely to miss the 6-month follow-up. Use of a patient contact system (OR, 0.55; 95% CI, 0.35 to 0.87, P = 0.01) and increased number of preoperative visits (OR, 0.91; 95% CI, 0.84 to 0.99, P = 0.033) were associated with decreased odds of missing the 12-month follow-up. Patients who missed the 6-month follow-up were more likely to miss the 12-month follow-up (OR, 5.38; 95% CI, 3.45 to 8.40; P < 0.001). CONCLUSION: Implementing an electronic patient contact system while increasing focus on patients with few preoperative visits and who miss the 6-month follow-up can reduce the risk of missed follow-up at 12 months after shoulder arthroscopy.

Identification of Glandular (Acinar)/Tubule Formation in Invasive Carcinoma of the Breast: A Study to Determine Concordance Using the World Health Organization Definition.

CONTEXT.­: The Nottingham Grading System (NGS) developed by Elston and Ellis is used to grade invasive breast cancer (IBC). Glandular (acinar)/tubule formation is a component of NGS. OBJECTIVE.­: To investigate the ability of pathologists to identify individual structures that should be classified as glandular (acinar)/tubule formation. DESIGN.­: A total of 58 hematoxylin-eosin photographic images of IBC with 1 structure circled were classified as tubules (41 cases) or nontubules (17 cases) by Professor Ellis. Images were sent as a PowerPoint (Microsoft) file to breast pathologists, who were provided with the World Health Organization definition of a tubule and asked to determine if a circled structure represented a tubule. RESULTS.­: Among 35 pathologists, the κ statistic for assessing agreement in evaluating the 58 images was 0.324 (95% CI, 0.314-0.335). The median concordance rate between a participating pathologist and Professor Ellis was 94.1% for evaluating 17 nontubule cases and 53.7% for 41 tubule cases. A total of 41% of the tubule cases were classified correctly by less than 50% of pathologists. Structures classified as tubules by Professor Ellis but often not recognized as tubules by pathologists included glands with complex architecture, mucinous carcinoma, and the "inverted tubule" pattern of micropapillary carcinoma. A total of 80% of participants reported that they did not have clarity on what represented a tubule. CONCLUSIONS.­: We identified structures that should be included as tubules but that were not readily identified by pathologists. Greater concordance for identification of tubules might be obtained by providing more detailed images and descriptions of the types of structures included as tubules.

The Effect of Guided Growth Surgery on Langenskiold Stage and Mechanical Axis in Early-Onset Blount Disease: A Retrospective Case Series.

INTRODUCTION: Our understanding of the efficacy of guided growth surgery with tension-band plating (TBP) in early-onset Blount disease is evolving. Preliminary work has demonstrated that TBP can normalize the mechanical axis, yet its effect on Langenskiöld stage (LS) has not previously been reported. The primary outcome of this study was improvement in LS after TBP. Secondary outcomes were improvement in LS at most recent follow-up and improvement in mechanical axis deviation (MAD), mechanical medial proximal tibial angle, and mechanical lateral distal femoral angle at treatment completion and most recent follow-up. METHODS: A retrospective review was done of patients with early-onset Blount disease treated with TBP between January 1, 2010, and December 31, 2019, across two institutions. Inclusion criteria were a radiographic diagnosis of early-onset Blount disease (LS changes present), surgery with TBP, and follow-up beyond implant removal. Radiographs before surgery, at removal of hardware (ROH), and at most recent follow-up were evaluated. RESULTS: Twenty-five limbs in 16 children who underwent TBP at a mean age of 5.8 ± 2.3 years were included. Implants were in situ a mean of 1.9 ± 0.7 years. The mean follow-up after ROH was 3.6 ± 1.4 years. LS ranged from 1 to 5 preoperatively with 14 of 25 limbs (56%) staged ≥3. LS improved in 15 of 25 limbs (60%) at ROH and in 21 of 25 limbs (84%) at most recent follow-up. Langenskiöld changes resolved in 7 of 25 limbs (28%) at most recent follow-up. Preoperatively, the MAD was varus in all limbs, but at ROH, the MAD had improved in 22 of 23 limbs with neutral or valgus alignment in 20 of 23 limbs (87%). At most recent follow-up, 16 of 23 limbs (70%) maintained improved alignment. DISCUSSION: There was improvement/resolution of LS and varus deformity in early-onset Blount disease in most patients who underwent TBP. Based on these results, TBP for early-onset Blount disease should be the first-line surgical treatment. LEVEL OF EVIDENCE: IV.

Single Long-Incision Minimally Invasive Surgery.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The objective of this study is to determine differences in outcomes in patients with adolescent idiopathic scoliosis undergoing spinal deformity correction surgery using a posterior spinal fusion (PSF) approach versus single and triple-incision minimally invasive surgery (MIS). SUMMARY OF BACKGROUND DATA: MIS increased in popularity as surgeons' focus moved towards soft tissue preservation, but it carries technical demands and increased surgical time compared with PSF. PATIENTS AND METHODS: Surgeries performed from 2016 to 2020 were included. Cohorts were formed based on surgical approach: PSF versus single long-incision MIS (SLIM) versus traditional MIS [3-incision MIS (3MIS)]. There were a total of 7 subanalyses. Demographic, radiographic, and perioperative data were collected for the 3 groups. Kruskal-Wallis and χ 2 tests were used for continuous and categorical variables, respectively. RESULTS: Five hundred thirty-two patients met our inclusion criteria, 294 PSF, 179 3MIS, and 59 SLIM.Estimated blood loss (mL) ( P < 0.00001) and length of stay (LOS) ( P < 0.00001) was significantly higher in PSF than in SLIM and 3MIS. Surgical time was significantly higher in 3MIS than in PSF and SLIM ( P = 0.0012).Patients who underwent PSF had significantly lower postoperative T5 to T12 kyphosis ( P < 0.00001) and percentage kyphosis change ( P < 0.00001). Morphine equivalence was significantly higher in the PSF group during total hospital stay ( P = 0.0042).Patients who underwent SLIM and 3MIS were more likely to return to noncontact ( P = 0.0096) and contact sports ( P = 0.0095) within 6 months and reported lower pain scores ( P < 0.001) at 6 months postoperation. CONCLUSION: SLIM has a similar operative time to PSF and is technically similar to PSF while maintaining the surgical and postoperative outcome advantages of 3MIS.

Prevalence and Risk Factors for Missed Short-term Follow-up After Primary Total Shoulder Arthroplasty.

INTRODUCTION: The importance of consistent postoperative follow-up has been established for collecting patient-reported outcomes and surveilling for potential complications. Despite this, the prevalence of and risk factors for missed short-term follow-up after elective shoulder arthroplasty remain limited. METHODS: A retrospective review of consecutive primary anatomic total shoulder arthroplasty (aTSA) and reverse total shoulder arthroplasty cases with a minimum of 12-month follow-up performed by a single, fellowship-trained shoulder surgeon was undertaken from January 2015 to December 2021. Demographic patient and surgical data, including age, sex, marital status, self-identified race, body mass index, American Society of Anesthesiologists score, age-adjusted Charlson Comorbidity Index, prior ipsilateral shoulder surgery and/or contralateral arthroplasty, distance from home to clinic, smoking status, and hospital length of stay, were collected. The follow-up at 1 week, 6 weeks, 6 months, 12 months, and 24 months and beyond was determined. Patient-related and surgical predictors for missing the 12-month and 24-month follow-up were identified. RESULTS: There were 295 cases included (168 aTSA and 127 reverse total shoulder arthroplasty), of whom 199 (67%) were women. Of the total cases, 261 (86%) were eligible for 24-month follow-up. Patients undergoing aTSA, those of younger age, those of male sex, and those who missed their 6-week and 6-month follow-up were significantly more likely to miss the 12-month follow-up visit. Following multivariable analysis, a missed 6-month follow-up (OR 10.10, 95% CI 5.32 to 19.16, P < 0.001) was associated with 12-month visit nonattendance, and increasing age (per year) (OR 0.96, 95% CI 0.93 to 0.99, P = 0.011) was associated with improved 12-month follow-up. Not having a surgical complication within 6 months postoperatively, not undergoing ipsilateral revision arthroplasty, and missing the 1-week and 12-month follow-up were significantly associated with missing the 24-month follow-up. After multivariable analysis, missing the 1-week (OR 3.07, 95% CI 1.12 to 8.41, P = 0.029) and 12-month (OR 3.84, 95% CI 2.11 to 6.99, P < 0.001) follow-ups was associated with missing the 24-month visit, whereas having a postoperative complication was associated with increased attendance at 24 months (OR 0.38, 95% CI 0.14 to 0.99, P = 0.047). DISCUSSION: Strategies for preventing missed short-term follow-up should be focused on ensuring that patients undergoing TSA attend the 6-month and 12-month visit, particularly among younger patients and those with an uneventful postoperative course.

Does a dedicated "Scoliosis Team" and surgical standardization improve outcomes in adolescent idiopathic scoliosis surgery and is it reproducible?

PURPOSE: The objective of this study was to determine if standardization improves adolescent idiopathic scoliosis (AIS) surgery outcomes and whether it is transferrable between institutions. METHODS: A retrospective review was conducted of AIS patients operated between 2009 and 2021 at two institutions (IA and IB). Each institution consisted of a non-standardized (NST) and standardized group (ST). In 2015, surgeons changed institutions (IA- > IB). Reproducibility was determined between institutions. Median and interquartile ranges (IQR), Kruskal-Wallis, and χ2 tests were used. RESULTS: 500 consecutive AIS patients were included. Age (p = 0.06), body mass index (p = 0.74), preoperative Cobb angle (p = 0.53), and levels fused (p = 0.94) were similar between institutions. IA-ST and IB-ST had lower blood loss (p < 0.001) and shorter surgical time (p < 0.001). IB-ST had significantly shorter hospital stay (p < 0.001) and transfusion rate (p = 0.007) than IB-NST. Standardized protocols in IB-ST reduced costs by 18.7%, significantly lowering hospital costs from $74,794.05 in IB-NST to $60,778.60 for IB-ST (p < 0.001). Annual analysis of surgical time revealed while implementation of standardized protocols decreased operative time within IA, when surgeons transitioned to IB, and upon standardization, IB operative time values decreased once again, and continued to decrease annually. Additions to standardized protocol in IB temporarily affected the operative time, before stabilizing. CONCLUSION: Surgeon-led standardized AIS approach and streamlined surgical steps improve outcomes and efficiency, is transferrable between institutions, and adjusts to additional protocol changes.

Does Morbid Obesity (BMI ≥40 kg/m2) Impact Operative Time, Blood Loss, Length of Stay, or Complications Following Anatomic Total Shoulder Arthroplasty?

Objectives: There have been conflicting reports regarding the effects of obesity on both surgical time and blood loss following anatomic shoulder arthroplasty. Varying categories of obesity has made comparison amongst existing studies difficult. Methods: A retrospective review of consecutive anatomic shoulder arthroplasty cases (aTSA) was undertaken. Demographic data, including age, gender, body mass index (BMI), age-adjusted Charleson Comorbidity Index (ACCI), operative time, hospital length of stay (LOS), and both POD#1 and discharge visual analogue score (VAS) was collected. Intra-operative total blood volume loss (ITBVL) and need for transfusion was calculated. BMI was categorized as non-obese (<30 kg/m2), obese (30-40 kg/m2) and morbidly obese (≥40 kg/m2). Unadjusted associations of BMI with operative time, ITBVL and LOS were examined using Spearman correlation coefficients. Regression analysis was used to identify factors associated with hospital LOS. Results: There were 130 aTSA cases performed, including 45 short stem and 85 stemless implants, of which 23 (17.7%) were morbidly obese, 60 (46.2%) were obese and 47 (36.1%) were non-obese. Median operative time for the morbidly obese cohort was 119.5 minutes (IQR 93.0, 142.0) versus 116.5 minutes (IQR 99.5, 134.5) for the obese cohort versus 125.0 minutes (IQR, 99.0, 146.0) for the non-obese cohort. (P=0.61) The median ITBVL for the morbidly obese cohort was 235.8 ml (IQR 144.3, 329.7) versus 220.1 ml (IQR 147.7, 262.7) for the obese cohort versus 216.3 ml (IQR 139.7, 315.5) for the non-obese cohort. (P=0.72). BMI ≥40kg/m2 (IRR 1.32, P=0.038), age (IRR 1.01, P=0.026), and female gender (IRR 1.54, P<0.001) were predictive of increased LOS. There was no difference with regards to in-hospital medical complications (P=0.13), surgical complications (P=1.0), need for re-operation (P=0.66) and 30-day return to the ER (P=0.06). Conclusion: Morbid obesity was not associated with increased surgical time, ITBVL and perioperative medical or surgical complications following aTSA, though it was predictive of increased hospital LOS.

Effect of Pedicle Screw Size on Surgical Outcomes Following Surgery for 412 Adolescent Idiopathic Scoliosis Patients.

STUDY DESIGN: Retrospective Review. OBJECTIVE: The objective of this study was to determine differences in surgical and post-operative outcomes in AIS patients undergoing spinal deformity correction surgery using standard or large pedicle screw size. SUMMARY OF BACKGROUND: Use of pedicle screw fixation in spinal deformity correction surgery is considered safe and effective. Still, the small size of the pedicle and the complex 3D anatomy of the thoracic spine makes screw placement challenging, with improper pedicle screw fixation leading to catastrophic complications including injuries to nerve roots, spinal cord, and major vessels. Thus, insertion of larger diameter screw sizes has raised concerns amongst surgeons, especially in the pediatric population. MATERIALS AND METHODS: AIS patients undergoing PSF between 2013 and 2019 were included. Demographic, radiographic, and operative outcomes collected. Patients in the large screw size group (GpI) received 6.5 mm diameter screw sizes at all levels while standard screw size group (GpII) received 5.0 to 5.5 mm diameter screw sizes at all levels. Kruskall-Wallis and Fisher's exact test performed for continuous and categorical variables respectively.Subanalyses included (1) screw accuracy in patients with available CT scans, (2) stratified analysis of large- and standard-screw patients with ≥60% flexibility rate, (3) stratified analysis of large- and standard-screw patients with <60% flexibility rate, and (4) matched analysis of large- and standard-screw patients by surgeon and year of surgery. RESULTS: GpI patients experienced significantly higher overall curve correction ( P <0.001), with 87.6% experiencing at least one grade reduction of apical vertebral rotation from preoperative to postoperative visit( P =0.008).Patients with larger screws displayed higher postoperative kyphosis. No patient experienced medial breaching. CONCLUSION: Large screw sizes have similar safety profiles to standard screws without negatively impacting surgical and perioperative outcomes in AIS patients undergoing PSF. Additionally, coronal, sagittal, and rotational correction is superior for larger-diameter screws in AIS patients.

EZH2 Protein Expression in Estrogen Receptor Positive Invasive Breast Cancer Treated With Neoadjuvant Endocrine Therapy: An Exploratory Study of Association With Tumor Response.

INTRODUCTION: Neoadjuvant endocrine therapy (NET) can be used to treat estrogen receptor positive (ER+) invasive breast cancer (IBC). Tumors with Ki67>10% after 2 to 4 weeks of NET are considered resistant to endocrine therapy. Enhancer of Zeste Homolog 2 (EZH2) is a targetable oncoprotein and overexpression in ER+ IBC has been linked to resistance to endocrine therapy. We examined whether EZH2 expression levels in ER+ IBC could be used to predict response to NET. MATERIALS AND METHODS: We retrospectively identified 46 patients with localized ER+ HER2/neu negative IBC treated with a minimum of 4 weeks of NET. We quantified EZH2 nuclear expression in pretherapy core biopsies using a score that included intensity and percent of cells staining. Ki67 was evaluated in both pretherapy core biopsies and posttherapy tumor resections and scored according to the guidelines of the International Ki67 Working Groups, with a global weighted score. Ki67≤10% after NET was considered endocrine responsive. Logistic regression analysis was performed to determine the association between EZH2 expression and response to NET. RESULTS: We found significant associations of tumor grade ( P =0.011), pretherapy Ki67 ( P =0.003), and EZH2 ( P <0.001), with response to NET. On logistic regression adjusted for tumor grade and pretherapy Ki67, increased EZH2 scores were associated with decreased odds of endocrine responsiveness, defined as posttreatment Ki67≤10% (odds ratio=0.976, 95% CI, 0.956 to 0.997; P =0.026). In addition, with EZH2 score in the model, associations of tumor grade and pretreatment Ki67 with posttreatment Ki67≤10% response to NET became not significant. CONCLUSIONS: Our results suggest that EZH2 might be a useful biomarker to predict response to NET.

A Comparison of Operative Time and Intraoperative Blood Volume Loss Between Stemless and Short-stem Anatomic Total Shoulder Arthroplasty: A Single Institution's Experience.

INTRODUCTION: There has been increasing interest in the use of stemless humeral implants for total shoulder arthroplasty when compared with both short-stem (SS) and standard-length implants. Although evidence for decreased surgical time and blood loss exists for stemless versus standard-length stems, far less literature exists comparing these clinical parameters for stemless versus SS implants. METHODS: A retrospective review of consecutive anatomic total shoulder arthroplasty (aTSA) cases conducted by a single, fellowship-trained shoulder surgeon was undertaken from January 2016 through January 2022 with the exception of March 2020 through January 2021 secondary to the COVID-19 pandemic. Demographic patient and surgical data, including age, sex, body mass index, American Society of Anesthesiologists score, age-adjusted Charlson Comorbidity Index, prior ipsilateral shoulder arthroscopy, surgical time, use of a Hemovac drain and/or tranexamic acid, hospital length of stay (LOS), and both postoperative day #1 (POD 1) and discharge visual analog scores. The use of a stemless or SS implant was recorded. Intraoperative total blood volume loss (TBVL) was calculated, in addition to the need for either intraoperative or postoperative transfusions. Nonparametric analysis of covariance was used to examine effects of stemless versus SS aTSA on surgical time and intraoperative TBVL adjusted for demographic, clinical, and surgical variables. RESULTS: There were 47 SS and 83 stemless anatomic implants included, of which 74 patients (57%) overall were women. The median surgical time for the stemless cohort was 111 minutes (IQR 96-130) versus 137 minutes (IQR 113-169) for the SS cohort (P < 0.00001). The median intraoperative TBVL for the stemless cohort was 298.3 mL (IQR 212.6-402.8) versus 359.7 mL (IQR 253.9-415.0) for the SS cohort (P = 0.05). After multivariable regression analysis, use of stemless humeral implants was independently associated with both decreased surgical time and intraoperative blood loss (P < 0.001 and P = 0.005, respectively). There was a shorter median hospital LOS in the stemless group (2 days [IQR 1-2] versus 2 days [IQR 2-3], P = 0.03). The visual analog score pain score at discharge was lower among the stemless cohort (0 [IQR 0-3] versus 4 [IQR 2-6], P < 0.00001). Increased surgical time was associated with intraoperative TBVL (r = 0.340, P < 0.0001). DISCUSSION: Stemless aTSA is associated with a markedly decreased surgical time and intraoperative TBVL when compared with a SS aTSA. Furthermore, the use of a stemless implant results in a shorter hospital LOS and lower discharge pain scores.

Posterior-only Resection of Single Hemivertebrae With 2-Level Versus >2-Level Fusion: Can We Improve Outcomes?

BACKGROUND: The outcomes of congenital scoliosis (CS) patients undergoing hemivertebra (HV) resection surgery with a 2-level fusion versus a >2-level fusion are unclear. We hypothesized that CS patients undergoing HV resection and a >2-level fusion have decreased curve progression and reoperation rates compared with 2-level fusions. METHODS: Retrospective review of prospectively collected data from a multicenter scoliosis database. Fifty-three CS patients (average age 4.5, range 1.2 to 10.9 y) at index surgery were included. Radiographic and surgical parameters, complications, as well as revision surgery rates were tracked at a minimum of 2-year follow-up. RESULTS: Twenty-six patients had a 2-level fusion while 27 patients had a >2-level fusion with similar age and body mass index between groups. The HV was located in the lumbar spine for 69% (18/26) 2-level fusions and 30% (8/27) >2-level fusions ( P =0.006). Segmental HV scoliosis curve was smaller in 2-level fusions compared to >2-level fusions preoperatively (38 vs. 50 degrees, P =0.016) and at follow-up (25 vs. 34 degrees, P =0.038). Preoperative T2-T12 (28 vs. 41 degrees, P =0.013) and segmental kyphosis (11 vs. 23 degrees, P =0.046) were smaller in 2-level fusions, but did not differ significantly at postoperative follow-up (32 vs. 39 degrees, P =0.22; 13 vs. 11 degrees, P =0.64, respectively). Furthermore, the 2 groups did not significantly differ in terms of surgical complications (27% vs. 22%, P =0.69; 2-level fusion vs. >2-level fusion, respectively), unplanned revision surgery rate (23% vs. 22%, 0.94), growing rod placement or extension of spinal fusion (15% vs. 15%, P =0.95), or health-related quality of life per the EOS-Questionnaire 24 (EOSQ-24). Comparison of patients with or without the need for growing rod placement or posterior spinal fusion revealed no significant differences in all parameters analyzed. CONCLUSIONS: Two-level and >2-level fusions can control congenital curves successfully. No differences existed in curve correction, proximal junctional kyphosis or complications between short and long-level fusion after HV resection. Both short and long level fusions are viable options and generate similar risk of revision. The decision should be individualized by patient and surgeon.

The Volume-Cost Relationship: How Does Surgical Volume Affect Cost and Value in AIS Surgery.

STUDY DESIGN: Retrospective review. OBJECTIVE: The objective of this study was to evaluate and compare distribution of hospital and operating room charges and outcomes during posterior spinal fusion for adolescent idiopathic scoliosis (AIS) patients by high-volume (HV) and standard-volume (SV) surgeons at one institution and examine potential cost savings. SUMMARY OF BACKGROUND DATA: Increased surgical volume has been associated with improved perioperative outcomes after spinal deformity correction. However, there is a lack of information on how this may affect hospital costs. METHODS: Retrospective study of AIS patients undergoing posterior spinal fusion between 2013 and 2019. Demographic, x-ray, chart review and hospital costs were collected and compared between HV surgeons (≥50 AIS cases/y) and SV surgeons (<50/y). Comparative analyses were computed using Wilcoxon rank-sum, Kruskal-Wallis, and the Fisher exact tests. Average values with corresponding minimum-maximum rages were reported. RESULTS: A total of 407 patients (HV: 232, SV: 175) operated by 4 surgeons (1 HV, 3 SV). Radiographic parameters were similar between the groups. HV surgeons had significantly lower estimated blood loss (385.3 vs. 655.6 mL, P <0.001), fewer intraoperative transfusions (10.8% vs. 25.1%, P <0.001), shorter surgery time (221.6 vs. 324.9 min, P <0.001), and lower radiation from intraoperative fluoroscopy (4.4 vs. 6.4 mGy, P <0.001). HV patients had a significantly lower length of stay (4.3 vs. 5.3, P <0.001) and complication rate (0.4% vs. 4%, P =0.04).HV surgeons had significantly lower total costs ($61,716.24 vs. $72,745.93, P <0.001). This included lower transfusion costs ( P <0.001), operative time costs ( P <0.001), screw costs ( P <0.001), hospital stay costs ( P <0.001), and costs associated with 30-day emergency department returns ( P <0.001). CONCLUSION: HV surgeons had significantly lower operative times, lower estimated blood loss and transfusion rates and lower perioperative complications requiring readmission or return to emergency department resulting in lower health care costs. LEVEL OF EVIDENCE: Level III.

Incidence and Risk Factors for Patient-related Short-term Cancellation of Elective Arthroscopic Surgery: A Case-matched Study.

INTRODUCTION: Short-term cancellation of elective ambulatory orthopaedic surgery can result in disruption to the process flow of the operating room, with resultant negative financial implications for the health system. The risk factors for patient-related short-term cancellations within 24 hours of the surgical date have not been well defined. METHODS: A retrospective review of a single orthopaedic surgery electronic internal database was done to identify all cancellations from January 1, 2016, through December 31, 2019, which were made within 24 hours of the surgical date. Inclusion criteria included elective arthroscopic procedures canceled solely for patient-related issues. Any cancellation for surgeon-related or ambulatory center-related reasons was excluded. Demographic patient and surgical data, including insurance type, employment status, previous history of cancellation for the same surgery, socioeconomic status based on the Area Deprivation Index, and surgery type, were tabulated. Each cancellation was matched 1:2 with noncanceled cases based on the anatomic site of the arthroscopy scheduled. Multivariable logistic regression was used to examine associations of patient demographic and medical characteristics with surgical cancellation. RESULTS: There were 4,715 total arthroscopic procedures done during the study period, of which 126 (2.7%) were canceled within 24 hours of the surgery date. The mean age of the canceled cases was 44.9 ± 16.1 years (range, 14 to 77 years), with 46 females (43%) included. The presence of MRI of the involved joint within 6 months of surgery (adjusted odds ratio [aOR], 0.39, 95% confidence interval [CI], 0.17 to 0.91) and current employment (aOR, 0.56, 95% CI, 0.33-0.94) were independently predictive of noncancellation. Current smokers were more likely to cancel within 24 hours of surgery (aOR, 2.63, 95% CI, 1.4-4.9). Finally, having previously canceled the same surgery was significantly associated with a current surgical cancellation (P = 0.004). DISCUSSION: Identification of the factors associated with short-term patient-related cancellation of elective arthroscopy may serve as the basis for preoperative interventions aimed specifically at those more likely to cancel. In turn, these interventions can minimize preventable cancellations.

EZH2 Protein Expression in Triple-negative Breast Cancer Treated With Neoadjuvant Chemotherapy: An Exploratory Study of Association With Tumor Response and Prognosis.

INTRODUCTION: Neaodjuvant chemotherapy is used to treat high risk triple-negative breast cancer (TNBC). Residual cancer burden (RCB) is used to predict risk of relapse after neoadjuvant chemotherapy (NAC); however, it cannot predict disease recurrence with certainty. EZH2 is a targetable oncogenic protein overexpressed in TNBC and associated with metastasis and stem cell expansion. We quantified EZH2 protein expression in TNBC before NAC to examine potential utility as a predictive and prognostic biomarker. MATERIALS AND METHODS: We retrospectively identified 63 patients with localized TNBC treated with NAC. We quantified EZH2 nuclear expression in pretherapy biopsies using a score which included intensity and percent of positive cells at each intensity. EZH2 expression was evaluated as a continuous variable and dichotomized at a score of 210. Logistic regression analysis was used to determine association between EZH2 expression and RCB, tumor-infiltrating lymphocytes, clinicopathologic features and disease-free survival. RESULTS: There was no significant association between EZH2 score and posttreatment RCB class evaluated as a continuous variable (P=0.831) or dichotomized at 210 (P=0.546). On multivariable logistic regression, adjusted for covariates including RCB, EZH2 >210 was associated with development of metastasis (odds ratio=14.35, 95% confidence interval: 2.69-76.66; P=0.002). Logistic regression was run with EZH2 scores as a continuous variable and increased EZH2 score was associated with metastasis (odds ratio=1.10, 95% confidence interval: 1.00-1.03; P=0.047). CONCLUSION: In our study of TNBC treated with NAC, high EZH2 expression in pretherapy core biopsies was significantly associated with metastatic recurrence independent of RCB. The potential value of EZH2 as a biomarker to improve stratification of outcome after NAC should be explored further.

Black and Hispanic Patients Do Not Stay Longer After Primary Total Knee Arthroplasty: Results From an Urban Center Serving a Predominantly Minority Cohort.

INTRODUCTION: Previous reports identified minority race/ethnicity to be an independent risk factor for prolonged length of stay (LOS); however, these cohorts consisted of predominantly White patients. This study sought to evaluate minority status as an independent risk factor for prolonged LOS after primary total knee arthroplasty (TKA) in a predominantly Hispanic and Black cohort. METHODS: This was a retrospective study using an institutional database of patients who underwent primary TKA between the years 2016 and 2019. Demographic and socioeconomic data, smoking, body mass index (BMI), medical comorbidities, discharge disposition, and 30-day readmission rates were collected. Patients were first categorized into racial/ethnic groups (Hispanic, Black, or White). An univariate analysis was performed comparing patient characteristics between racial/ethnic groups using the Wilcoxon rank sum, chi-squared, and Fisher exact tests. We then categorized patients into two groups-normal LOS (discharged on postoperative day 1 to 2) and prolonged LOS (discharged after postoperative day 2). An univariate analysis was again performed comparing patient characteristics between LOS groups using Wilcoxon rank sum, chi-squared, and Fisher exact tests. After identifying risk factors markedly associated with LOS, a multivariate logistic regression analysis was performed to identify independent risk factors for prolonged LOS. RESULTS: A total of 3,093 patients were included-47.9% Hispanic and 38.3% Black. Mean LOS was 2.9 ± 1.6 days. An univariate analysis found race/ethnicity, age, low socioeconomic status (SES), discharge disposition, insurance type, weekday of surgery, BMI >40, smoking, increased American Society of Anesthesiologists (ASA)/Charlson Comorbidity Index (CCI) and several medical comorbidities to be associated with prolonged LOS (P < 0.05). A multivariate logistic regression analysis found Black and Hispanic patients were less likely to have prolonged LOS after adjusting for associated risk factors. White race/ethnicity, nonhome discharge, low SES, weekday of surgery, smoking, BMI >40, and increased ASA and CCI were identified as independent risk factors for prolonged LOS (P < 0.05). The overall 30-day readmission rate was 3.6%, with no notable difference between racial/ethnic and LOS groups (P = 0.98 and P = 0.78). CONCLUSION: In contrast to previous reports, our study found that after adjusting for associated risk factors, minority patients do not have prolonged LOS after primary TKA in an urban, socioeconomically disadvantaged, predominantly minority patient cohort. White race/ethnicity, nonhome discharge, low SES, weekday of surgery, smoking, BMI >40, increased CCI, and ASA were all found to be independent risk factors for prolonged LOS. These findings highlight the need to further investigate the role of race/ethnicity on LOS after primary TKA using large-scale, randomized controlled trials with equally represented patient cohorts.