Effect of COVID-19 on computed tomography usage and critical test results in the emergency department: an observational study.

BACKGROUND: The effect of the coronavirus disease 2019 (COVID-19) pandemic on new or unexpected radiologic findings in the emergency department (ED) is unclear. The aim of this study was to determine the effect of the COVID-19 pandemic on the number of computed tomography (CT) critical test results in the ED. METHODS: We performed a retrospective observational study of ED CT usage at 4 Ontario hospitals (1 urban academic, 1 northern academic, 1 urban community and 1 rural community) over 1 month during the COVID-19 pandemic (April 2020) and over the same month 1 year earlier (April 2019; before the pandemic). The CT findings from 1 of the 4 hospitals, Hamilton Health Sciences, were reviewed to determine the number of critical test results by body region. Total CT numbers were compared using Poisson regression and CT yields were compared using the χ2 test. RESULTS: The median number of ED CT examinations per day was markedly lower during the COVID-19 pandemic than before the pandemic (82 v. 133, p < 0.01), with variation across hospitals (p = 0.001). On review of 1717 CT reports from Hamilton Health Sciences, fewer critical test results were demonstrated on CT pulmonary angiograms (43 v. 88, p < 0.001) and CT examinations of the head (82 v. 112, p < 0.03) during the pandemic than before the pandemic; however, the yield of these examinations did not change. Although the absolute number of all CT examinations with critical test results decreased, the number of CT examinations without critical results decreased more, resulting in a higher yield of CT for critical test results during the pandemic (46% [322/696] v. 37% [379/1021], p < 0.01). INTERPRETATION: Emergency department CT volumes markedly decreased during the COVID-19 pandemic, predominantly because there were fewer examinations with new or unexpected findings. This suggests that COVID-19 public information campaigns influenced the behaviours of patients presenting to the ED.

Multi-detector CT for suspected hip fragility fractures: A diagnostic test accuracy systematic review and meta-analysis.

To perform a systematic review (SR) and meta-analysis to determine the diagnostic test accuracy (DTA) of Multi-Detector Computed Tomography (MDCT) for detecting proximal femoral (hip) fragility fractures in patients with a negative initial radiograph. MEDLINE and EMBASE were searched to identify relevant studies published between January 2000 and May 2018. Articles underwent title and abstract screening followed by full-text screening. Study inclusion criteria are patients with suspected hip fracture, negative initial radiograph, MDCT as the index test, magnetic resonance imaging (MRI) or clinical follow-up as the reference standard, and DTA measure as the outcome. Demographic, methodologic, and study outcome data were extracted. Risk of bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 tool. DTA metrics were pooled using bivariate random-effects meta-analysis. From an initial 1385 studies, four studies reporting on 418 patients (174 with hip fractures) were included. Pooled summary statistics included the following: sensitivity (87%; 95% confidence interval [CI] 79-93), specificity (98%; 95% CI 95-99), and the area under the summary receiver operating characteristic (ROC) curve (0.972). MDCT has a high specificity for detecting hip fragility fractures, comparable to MRI, but a lower sensitivity. Local institutional factors may play a role in whether a patient receives MDCT or MRI, as imaging should not be delayed. If there is ongoing concern for fracture in a patient with a negative MDCT, MRI should be performed. Cautious interpretation of the results is warranted given the risk of bias and small sample size.

Femoroacetabular impingement in elite ice hockey players.

PURPOSE: The purpose of this study is to evaluate the presence of clinical and radiological femoroacetabular impingement (FAI) in elite ice hockey players and compare it to a control group of non-athletes. METHODS: Forty participants (20 non-athletes and 20 elite ice hockey athletes) underwent an evaluation of their hip joint, including assessment of range of motion and special provocative impingement tests. Two musculoskeletal radiologists assessed MRIs completed on each participant for radiological findings associated with FAI, including alpha angle, acetabular version angle, acetabular depth, and/or a lateral centre edge angle, and findings of labral and cartilage degeneration. A comparative analysis of the clinical and radiological findings was subsequently completed. RESULTS: There was a significant difference in the radiological CAM impingement measured by mean alpha angle between both groups (non-athletes: 43.2 degrees, SD 9.7; and athletes: 54.2 degrees, SD 12 (p = 0.003)). There were no statistically significant differences between the groups upon evaluating PINCER impingement. There were no statistically significant differences in clinical examination findings between both groups. CONCLUSION: MRI evidence suggests that CAM impingement is more common in the elite ice hockey athlete in comparison with non-athletes. However, as this is a pilot study examining findings in asymptomatic individuals, there is a need for a longitudinal prospective cohort study. In keeping with this, sufficient, long-term follow-up is required to assess at what point, if any, these subjects with radiological findings become symptomatic.