MRI-Derived Biomarkers Related to Sarcopenia: A Systematic Review.

BACKGROUND: MRI allows quantitatively assessing muscle quantity and quality. PURPOSE: To summarize the role of MRI as a noninvasive technique for the identification of in vivo surrogate biomarker of sarcopenia. STUDY TYPE: Systematic review. POPULATION: In April 2019, a systematic literature search (Medline/EMBASE) was performed to identify articles on the topic at issue. FIELD STRENGTH/SEQUENCE: No field strength or sequence restrictions. ASSESSMENT: After a literature search, study design, aim, sample size, demographics, magnetic field strength, imaged body region, MRI sequences, and imaging biomarker were extracted. STATISTICAL TESTS: Data are presented as frequencies and percentages. RESULTS: From 69 records identified through search query, 18 articles matched the inclusion criteria. All articles were published from 2012 and had a mainly prospective design (14/18, 78%). Sample size ranged from 9 to 284 subjects, for a total of 1706 enrolled subjects. Healthy subjects were enrolled or retrospectively selected in 8/18 (44%) articles, corresponding to 658 (39%) healthy subjects. Magnetic field strength was 1.5 or 3T in 14/18 (78%) studies. The most analyzed body regions were the thigh (7/18, 39%) and the trunk (6/18, 33%). Stratifying studies according to their aim, 13/18 (72%) studies focused on muscle quality and quantity, 3/18 (17%) studies on outcome prediction, and 2/18 articles (11%) addressed both aims. A wide set of MRI biomarkers have been proposed. Muscle cross-sectional area was the most used for muscle quantity estimation, while quantitative biomarkers of muscle fat content or fiber architecture were proposed to assess muscle quality. DATA CONCLUSION: The proposed biomarkers were assessed using different MRI sequences for different body regions in different subjects/patient cohorts, pointing out a lack of standardization on this topic. Future studies should test and compare the performance of proposed MRI biomarkers for sarcopenia characterization and quantification using a standardized experimental setup. LEVEL OF EVIDENCE: 1 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2020;51:1117-1127.

How the COVID-19 Pandemic Affected Attendance at a Tertiary Orthopedic Center Emergency Department: A Comparison between the First and Second Waves.

Italy was the first European country to face the SARS-CoV-2 virus (COVID-19) pandemic in 2020. The country quickly implemented strategies to contain contagions and re-organize medical resources. We evaluated the COVID-19 effects on the activity of a tertiary-level orthopedic emergency department (ED) during the first and second pandemic waves. We retrospectively collected and compared clinical radiological data of ED admissions during four periods: period A, first pandemic wave; period B, second pandemic wave; period C, three months before the COVID-19 outbreak; period D, same timeframe of the first wave but in 2019. During period A, we found a reduction in ED admissions (-68.2% and -59.9% compared with periods D and C) and a decrease in white codes (non-urgent) (-7.5%) compared with pre-pandemic periods, with a slight increase for all other codes: +6.3% green (urgent, not critical), +0.8% yellow (moderately critical) and +0.3% red (highly urgent, risk of death). We observed an increased rate of fracture diagnosis in period A: +14.9% and +13.3% compared with periods D and C. Our study shows that the COVID-19 pandemic caused a drastic change in the ED patient flow and clinical radiological activity, with a marked reduction in admissions and an increased rate of more severe triage codes and diagnosed fractures.