ChatGPT-4 Knows Its A B C D E but Cannot Cite Its Source.

Introduction: The artificial intelligence language model Chat Generative Pretrained Transformer (ChatGPT) has shown potential as a reliable and accessible educational resource in orthopaedic surgery. Yet, the accuracy of the references behind the provided information remains elusive, which poses a concern for maintaining the integrity of medical content. This study aims to examine the accuracy of the references provided by ChatGPT-4 concerning the Airway, Breathing, Circulation, Disability, Exposure (ABCDE) approach in trauma surgery. Methods: Two independent reviewers critically assessed 30 ChatGPT-4-generated references supporting the well-established ABCDE approach to trauma protocol, grading them as 0 (nonexistent), 1 (inaccurate), or 2 (accurate). All discrepancies between the ChatGPT-4 and PubMed references were carefully reviewed and bolded. Cohen's Kappa coefficient was used to examine the agreement of the accuracy scores of the ChatGPT-4-generated references between reviewers. Descriptive statistics were used to summarize the mean reference accuracy scores. To compare the variance of the means across the 5 categories, one-way analysis of variance was used. Results: ChatGPT-4 had an average reference accuracy score of 66.7%. Of the 30 references, only 43.3% were accurate and deemed "true" while 56.7% were categorized as "false" (43.3% inaccurate and 13.3% nonexistent). The accuracy was consistent across the 5 trauma protocol categories, with no significant statistical difference (p = 0.437). Discussion: With 57% of references being inaccurate or nonexistent, ChatGPT-4 has fallen short in providing reliable and reproducible references-a concerning finding for the safety of using ChatGPT-4 for professional medical decision making without thorough verification. Only if used cautiously, with cross-referencing, can this language model act as an adjunct learning tool that can enhance comprehensiveness as well as knowledge rehearsal and manipulation.

Anatomic Parameters for Diagnosing Congenital Lumbar Stenosis Based on Computed Tomography of 1,000 Patients.

INTRODUCTION: Quantitative parameters for diagnosis of congenital lumbar stenosis (CLS) have yet to be universally accepted. This study establishes parameters for CLS using CT, assessing the influences of patient sex, race, ethnicity, and anthropometric characteristics. METHODS: Interpedicular distance (IPD), pedicle length, canal diameter, and canal area were measured using 1,000 patients between 18 and 35 years of age who were without spinal pathology. RESULTS: Irrespective of disk level, threshold values for CLS were 16.1 mm for IPD, 3.9 mm for pedicle length, 11.5 mm for canal diameter, and 142.5 mm2 for canal area. Notable differences based on patient sex were observed, with men demonstrating larger CLS threshold values with respect to IPD and canal area across all vertebral levels from L1 to L5. Based on patient anthropometric factors, no strong or moderate associations were observed between any spinal measurement and patient height, weight, or body mass index across all levels from L1 to L5. However, notable differences were observed based on patient race and ethnicity from L1 to L5. Asian patients demonstrated the largest pedicle lengths, followed by White, Hispanic, and Black patients in descending order. White patients demonstrated the largest IPD, canal AP diameter, and canal area, followed by Asian, Hispanic, and Black patients in descending order. Black patients demonstrated the smallest values across all anatomic measurements relative to Asian, White, and Hispanic patients. CONCLUSION: This study reports 25,000 measurements of lumbar central canal dimensions to establish quantitative thresholds for the diagnosis of CLS. Although not influenced by patient height, weight, or body mass index as one might intuit, canal dimensions were influenced by patient sex, race, and ethnicity. These findings may help explain differences in predisposition or prevalence of lumbar nerve root compression among patients of different races, which can be important when considering rates of surgery and access to care.

Decreased Risk of Readmission and Complications With Preoperative GLP-1 Analog Use in Patients Undergoing Primary Total Joint Arthroplasty.

BACKGROUND: There has been considerable interest in the use of GLP-1 receptor analogs (GLP-1 RAs) for weight optimization in patients undergoing elective arthroplasty. As there is limited data regarding the implications of their use, our study aimed to evaluate the association between preoperative GLP-1 RA use and postoperative outcomes in patients undergoing primary total hip arthroplasty (THA) and total knee arthroplasty (TKA). METHODS: The TrinetX research network was queried to identify all patients undergoing primary THA or TKA between May 2005 and December 2023 across 84 health care organizations. Patients were stratified based on preoperative GLP-1 RA use. Propensity score matching (1:1) was performed to account for baseline differences in demographics, laboratory investigations, and comorbidities. Subsequently, risk ratios were evaluated for postoperative outcomes. RESULTS: A total of 268,504 and 386,356 patients underwent THA and TKA, of which 1,044 and 2,095 used preoperative GLP-1 RAs. After matching, GLP-1 RA use was associated with a decreased 90-day risk of periprosthetic joint infection (2.1 versus 3.6%, RR = 0.58, P = .042) and readmission (1.1 versus 2.0%, RR = 0.53, P = .017) following THA and TKA, respectively. There was no difference in the risk of all other outcomes between comparison groups. CONCLUSIONS: Preoperative GLP-1 RA use is associated with a 42% decreased risk of periprosthetic joint infection and 47% decreased risk of readmission in the 90-day postoperative period following THA and TKA, respectively, with no difference in other risks, including aspiration. Our findings indicate that GLP-1 RAs may be safe to use in patients undergoing elective arthroplasty; however, further studies are warranted to inform the routine use of GLP-1 RAs for weight management in THA and TKA patients.

Implementing a Hospitalist Comanagement Service in Orthopaedic Surgery.

➤ Hospitalist comanagement of patients undergoing orthopaedic surgery is a growing trend across the United States, yet its implementation in an academic tertiary care hospital can be complex and even contentious.➤ Hospitalist comanagement services lead to better identification of at-risk patients, optimization of patient care to prevent adverse events, and streamlining of the admission process, thereby enhancing the overall service efficiency.➤ A successful hospitalist comanagement service includes the identification of service stakeholders and leaders; frequent consensus meetings; a well-defined standardized framework, with goals, program metrics, and unified commands; and an occasional satisfaction assessment to update and improve the program.➤ In this article, we establish a step-by-step protocol for the implementation of a comanagement structure between orthopaedic and hospitalist services at a tertiary care center, outlining specific protocols and workflows for patient care and transfer procedures among various departments, particularly in emergency and postoperative situations.

Normative Measurements of L1 to S1 Neuroforaminal Dimensions Derived From Plain Film Radiography, Computed Tomography, and Magnetic Resonance Imaging.

STUDY DESIGN: Retrospective cohort. OBJECTIVE: To report normative measurements of L1 to S1 lumbar neuroforamina on plain film radiography (PFR), computed tomography (CT), and magnetic resonance imaging (MRI), accounting for patients' sex and ethnicity. BACKGROUND: The quantitative criteria fothe diagnosis of neuroforaminal stenosis remains unknown. Acquiring a thorough understanding of normative foraminal dimensions is a key step in formulating objective parameters for neuroforaminal stenosis. PATIENTS AND METHODS: We measured 988 images from 494 patients between 18 and 35 years old without spinal pathology who received PFR, CT, or MRI within 1 year of each other. Neuroforaminal measurements were defined as the height, area, and sagittal and axial widths. Statistical analyses were performed to assess relationships among PFR, CT, and MRI-derived neuroforaminal measurements, as well as the influence of patients' sex and ethnicity. RESULTS: 330 PFR, 377 CT, and 281 MRI were measured. Of these, 213 PFR and CT, 117 PFR and MRI, and 164 MRI and CT intrapatient images were compared. Statistically significant differences were observed among PFR, CT, and MRI measurements across all levels L1 to S1. PFR measurements were larger compared with those derived from CT and MRI. Weak-to-moderate correlations were observed between PFR and CT, PFR and MRI, and CT and MRI, with the magnitude of correlation decreasing caudally from L1 to S1. Variations in neuroforaminal anatomy were observed based on sex and ethnicity. CONCLUSION: This study reports 25,951 measurements of normal L1 to S1 neuroforaminal anatomy assessed by PFR, CT, and MRI. The values reported in this study may be used as normative reference measurements of the lumbar neuroforamina. PFR measurements of the neuroforamina are larger compared with those derived from CT and MRI across all levels from L1 to S1. There is a poor correlation between PFR, CT, and MRI when measuring the lumbar neuroforamina. Differences in neuroforaminal anatomy are evident based on patients' sex and ethnicity.

Normative Measurements of L1-S1 Segmental Angulation, Disk Space Height, and Neuroforaminal Dimensions Using Computed Tomography.

BACKGROUND AND OBJECTIVES: To establish normative anatomic measurements of lumbar segmental angulation (SA) and disk space height (DSH) in relation to neuroforaminal dimensions (NFDs), and to uncover the influence of patient demographic and anthropometric characteristics on SA, DSH, and NFDs. METHODS: NFDs, SA, and anterior, middle, and posterior DSH were measured using computed tomography of 969 patients. NFDs were defined as sagittal anterior-to-posterior width, foraminal height, and area. Statistical analyses were performed to assess associations among SA, DSH, NFDs, and patient height, weight, body mass index, sex, and ethnicity. RESULTS: SA and DSH measurements increased moving caudally from L1 to S1. Foraminal width decreased moving caudally from L1 to S1. Foraminal height and area demonstrated unimodal distribution patterns with the largest values clustered at L2-L3 on the right side and L3-L4 on the left. Significant differences in SA, DSH, and NFD measurements were observed based on the disk level. Inconsistent, marginal NFD differences were observed based on laterality. Across all disk levels, only weak-to-moderate correlations were observed between SA and DSH in relation to NFDs. Patient height, weight, and body mass index were only weakly associated with SA, DSH, and NFDs. Based on patient sex, significant differences were observed for SA, DSH, and NFD measurements from L1 to S1, with males demonstrating consistently larger values compared with females. Based on patient race and ethnicity, significant differences in SA and NFD measurements were observed from L1 to S1. CONCLUSION: This study describes 48 450 normative measurements of L1-S1 SA, DSH, and NFDs. These measurements serve as representative models of normal anatomic dimensions necessary for several applications including surgical planning and diagnosis of foraminal stenosis. Normative values of SA and DSH are not moderately or strongly associated with NFDs. SA, DSH, and NFDs are influenced by sex and ethnicity, but are not strongly or moderately influenced by patient anthropometric factors.

Comparison of L1-S1 neuroforaminal dimensions derived from plain film radiography versus computed tomography.

PURPOSE: To compare measurements of lumbar neuroforaminal dimensions (NFD) derived from plain film radiography (PFR) and computed tomography (CT) of young patients without spinal pathology. METHODS: We analyzed 213 patients between 18 and 35 years of age without spinal pathology who received PFR and CT within one year of each other. NFD were defined as foraminal height, sagittal anterior-to-posterior width, and area. Statistical analyses assessed correlations and differences between PFR- and CT-derived NFD measurements. RESULTS: 111 subjects were female and 102 were male. Significant differences between PFR- and CT-derived NFD measurements were observed for all levels L1-S1, with those for foraminal height listed as follows: 4.10 mm at L1-L2, 1.58 mm at L2-L3, 3.23 mm at L3-L4, 4.27 mm at L4-L5, and 1.75 mm at L5-S1. Regarding foraminal area, these differences were 72.20, 73.45, 61.80, 35.38, and 16.18 mm2, respectively. PFR-derived measurements of NFD were larger compared to those derived from CT across all levels (p < .001). Only weak (0 ≤ r ≤ .4) or moderate (.4 ≤ r ≤ .7) correlations were observed between PFR- and CT-derived NFD measurements for all levels from L1-S1. CONCLUSION: This study describes 9585 measurements from L1-S1 of neuroforaminal measurements derived from CT and plain film radiography from a sample of young patients without spinal pathology. Among these patients, plain film measurements of the neuroforamina are larger compared to those derived from CT for all levels from L1-S1. There is poor correlation and reliability between plain film and CT measurements of neuroforaminal dimensions.

Surface anatomical landmarks for spine surgery: A CT-based study of the sternal notch and sternal angle in 1,035 patients.

BACKGROUND: Understanding the location of surface anatomical landmarks in relation to the cervical and thoracic spine is important for a wide array of clinical applications. The objective of this study was to investigate the influence of patient demographic and anthropometric characteristics on the locations of the sternal notch and sternal angle in relation to the spine using computed tomography (CT) of a large cohort of young adult patients without spinal pathology. METHODS: Vertebral levels corresponding to the sternal notch and sternal angle were analyzed using CT of 1,035 patients. Influences of patient height, weight, body mass index (BMI), sex, and ethnicity were assessed. RESULTS: 567 male and 468 female patients were included in this study. Mean patient height, weight, BMI, and age were 1.68 ± 0.11 m, 81.94 ± 24.39 kg, 27.79 ± 7.9 kg/m2, and 25.9 ± 5.9 years. Of the 1,035 patients, 495 were Hispanic or Latino, 321 were Caucasian, 130 were African American, 68 were Asian, 5 were identified as "other," and 16 did not have racial or ethnic data available. The location of the sternal notch in relation to the thoracic spine demonstrated a bimodal distribution pattern clustered at the T2 and T3 vertebral bodies. The location of the sternal angle in relation to the thoracic spine demonstrated a bimodal distribution pattern clustered at the T4 and T5 vertebral bodies. Moderate, negative correlations were observed between patient weight and location of the sternal notch (r = -0.447; p <.001) and sternal angle (r = -0.499; p <.001), respectively. Zero significant correlations were observed between patient height and location of the sternal notch (r = -0.045; p =.377) or sternal angle (r = -0.080; p =.229). A weak, negative correlation was observed between patient BMI and location of the sternal notch (r = -0.378; p <.001). A moderate, negative correlation was observed between patient BMI and location of the sternal angle (r = -0.445; p <.001). The locations of the sternal landmarks did not differ based on patient sex, race or ethnicity. CONCLUSIONS: The location of the sternal notch most frequently corresponds to the T2 or T3 vertebral body, while the sternal angle is most frequently located at the T4 or T5 vertebral body. Increased patient weight is associated with relatively cephalad sternal landmarks. Patient height, sex, and ethnicity are not associated with either sternal landmark.

What Factors Are Associated With Arterial Line-Related Limb Ischemia in Patients on Extracorporeal Membrane Oxygenation? A Single-Center Retrospective Cohort Study.

OBJECTIVES: The primary purpose of this study was to identify factors associated with the development of arterial line-related limb ischemia in patients on extracorporeal membrane oxygenation (ECMO). The authors also sought to characterize and report the outcomes of patients who developed arterial line-related limb ischemia. DESIGN: Retrospective cohort study. SETTING: A single academic tertiary referral ECMO center. PARTICIPANTS: Consecutive patients who were treated with ECMO over 6 years. INTERVENTIONS: Use of arterial line. MEASUREMENTS AND MAIN RESULTS: A total of 278 consecutive ECMO patients were included, with 19 (7%) patients developing arterial line-related limb ischemia during the ECMO run. Postcannulation Sequential Organ Failure Assessment (SOFA) (adjusted odds ratio [aOR] 1.20, 95% CI 1.08-1.32), Acute Physiology and Chronic Health Evaluation-II (aOR 0.84, 95% CI 0.74-0.95), and adjusted Vasopressor Dose Equivalence (aOR 1.03, 95% CI 1.01-1.05) scores were independently associated with the development of arterial line-associated limb ischemia. A SOFA score of ≥17 at the time of ECMO cannulation had an 80% sensitivity and 87% specificity for predicting arterial line-related limb ischemia. CONCLUSIONS: Arterial line-related limb ischemia is much more common in ECMO patients than in the typical intensive care unit setting. The SOFA score may be useful in identifying which patients may be at risk for arterial line-related limb ischemia. As this was a single-center retrospective study, these results are inherently exploratory, and prospective multicenter studies are necessary to validate these results.

Racial and Ethnic Bias in Medical School Clinical Grading: A Review.

OBJECTIVE: Improving diversity in healthcare is a widely recognized national goal. The diversity of medical student matriculants has increased, yet this trend is not seen in the composition of competitive residency programs. In this review, we examine racial and ethnic disparities in medical student grading during clinical years and explore the consequences of how this may exclude minority students from accessing competitive residency positions. DESIGN: Following PRISMA guidelines, we searched PubMed, Embase, Scopus, and ERIC databases using variations of the terms "race," "ethnicity," "clerkship," "rotation," "grade," "evaluation", or "shelf exam." Of 391 references found using the criteria, 29 were related to clinical grading and race/ethnicity and included in the review. The GRADE criteria were used to determine the quality of evidence. SETTING: Johns Hopkins School of Medicine, Baltimore MD. RESULTS: Five studies examining a total of 107,687 students from up to 113 different schools found racial minority students receive significantly fewer Honors grades in core clerkships compared to White students. Three studies examining 94,814 medical student evaluations from up to 130 different schools found significant disparities in the wording of written clerkship evaluations based on race and/or ethnicity. CONCLUSIONS: A large body of evidence suggests the presence of racial bias in subjective clinical grading and written clerkship evaluations of medical students. Grading disparities can disadvantage minority students when applying to competitive residency programs and may contribute to a lack of diversity in these fields. As low minority representation has a negative impact on patient care and research advancement, strategies to resolve this issue must be further explored.

Preoperative opiate use leads to increased postoperative opiate use and readmissions after anterior cervical discectomy and fusion.

Background: Determine effects of pre-operative opiate use on anterior cervical discectomy and fusion (ACDF) surgery outcomes. Methods: The study design was a single center retrospective cohort study. Patient records were reviewed from 2013 and 2018 for elective 1 to 2 level ACDF surgeries. Patients were classified as: opiate naive (ON: no history of opiate) use, acute opiate (AO: <6 months preoperatively) use, and chronic opiate (CO: 6-12 months preoperatively) use based on prescription history before surgery. Opiate use was quantified by milligram morphine equivalents (MME) at 6-12 months preop, 0-6 months preop, 0-6 months postop, and 6-12 months postop. Charts were reviewed for American Society of Anesthesiologists (ASA) physical status classification and smoking history. Results: Readmission rates were 9.8% for ON, 9.1% for AO, and 30% for CO (P value <0.05). Average opiate use measured in MME 6-12 months post-surgery was 5.76 for ON, 18.44 for AO, and 39.92 for CO (P value <0.05). Readmission rate between nonsmokers, former smokers, and active smokers was 4.4%, 0%, and 10.8% (P value <0.05) at 30-90 days post-surgery, and 1.1%, 14.5%, and 2.5% (P value <0.05) in the 91 days to 1-year post-surgery. Conclusions: There is statistically significant relationship between CO and higher readmission rates after ACDF. Preoperative opiate use is also associated with increased opiate use 6-12 months after surgery. Smoking history is also associated with increased readmission rates.

Predictors of In-hospital Mortality in Cardiogenic Shock Patients on Vasoactive or Inotropic Support.

BACKGROUND: Though controversial, the short-duration in-patient use of inotropes in cardiogenic shock (CS) remain an ACC/AHA Class IIa indication, and are frequently used in the initial treatment of CS. We evaluated in-patient mortality and effect on mortality risk of commonly used vasoactive inotropic medications for the medical management of SCAI stage B and C cardiogenic shock patients in a tertiary care cardiac care unit: dobutamine, dopamine, milrinone, and norepinephrine. METHODS: We retrospectively evaluated 342 patients who received dobutamine, milrinone, dopamine, norepinephrine or a combination of these medications for SCAI stage B and C cardiogenic shock. Cox proportional hazards were used to form longitudinal mortality predictions. RESULTS: Overall in-patient mortality was 18%. Each 1 µg/kg/minute increase in dobutamine independently corresponded to a 15% increase in risk of mortality. High dose dobutamine >3 µg/kg/minute is associated with 3-fold increased risk compared to ⩽3 µg/kg/minute (P < .001). Use of milrinone, norepinephrine, and dopamine were not independently associated with mortality. CONCLUSION: We demonstrate that the overall in-hospital mortality of SCAI stage B and C cardiogenic shock patients medically managed on inotropes was not in excess of prior studies. Dobutamine was independently associated with mortality, while other vasoactive inotropic medications were not. Inotropes remain a feasible method of managing SCAI stage B and C cardiogenic shock.

Ryanodine receptor subtypes regulate Ca2+ sparks/spontaneous transient outward currents and myogenic tone of uterine arteries in pregnancy.

AIMS: Our recent study demonstrated that increased Ca2+ sparks and spontaneous transient outward currents (STOCs) played an important role in uterine vascular tone and haemodynamic adaptation to pregnancy. The present study examined the role of ryanodine receptor (RyR) subtypes in regulating Ca2+ sparks/STOCs and myogenic tone in uterine arterial adaptation to pregnancy. METHODS AND RESULTS: Uterine arteries isolated from non-pregnant and near-term pregnant sheep were used in the present study. Pregnancy increased the association of α and ß1 subunits of large-conductance Ca2+-activated K+ (BKCa) channels and enhanced the co-localization of RyR1 and RyR2 with the ß1 subunit in the uterine artery. In contrast, RyR3 was not co-localized with BKCa ß1 subunit. Knockdown of RyR1 or RyR2 in uterine arteries of pregnant sheep downregulated the ß1 but not α subunit of the BKCa channel and decreased the association of α and ß1 subunits. Unlike RyR1 and RyR2, knockdown of RyR3 had no significant effect on either expression or association of BKCa subunits. In addition, knockdown of RyR1 or RyR2 significantly decreased Ca2+ spark frequency, suppressed STOCs frequency and amplitude, and increased pressure-dependent myogenic tone in uterine arteries of pregnant animals. RyR3 knockdown did not affect Ca2+ sparks/STOCs and myogenic tone in the uterine artery. CONCLUSION: Together, the present study demonstrates a novel mechanistic paradigm of RyR subtypes in the regulation of Ca2+ sparks/STOCs and uterine vascular tone, providing new insights into the mechanisms underlying uterine vascular adaptation to pregnancy.

Pulvinar sign and abnormally high CSF WBC in posterior reversible encephalopathy syndrome.

Posterior reversible encephalopathy syndrome (PRES) is a reversible disease process in which cerebral edema is secondary to a trigger causes neurological symptoms. Our case presents an unusual MRI location and CSF analysis in a patient with PRES.