Background: Ultrasound is commonly used for evaluating rotator cuff tears. However, little training in ultrasound imaging is provided during orthopedic residents’ training period. Therefore, we performed this study to determine how many ultrasound scans are required for orthopedic residents to be competent and self-confident in the diagnosis of supraspinatus tendon tears and to investigate whether senior residents outperformed junior residents. Methods: We studied two third-year residents who had no previous experience of shoulder ultrasound and evaluated their ability to detect rotator cuff pathologies. Their learning curves were plotted using a cumulative summation analysis with a 20% acceptable failure rate compared to arthroscopic findings. Downward, upward, and horizontal cumulative summation trends indicated incompetence, exceptional competence, and competence, respectively. The diagnostic accuracy of third-year residents was compared with that of second-year residents and the number of cases required to gain self-confidence was evaluated. Results: Cumulative summation analysis showed that after 26–28 scans, residents achieved the competence to correctly diagnose supraspinatus tears: an upward trend was observed from the beginning for full-thickness tears and a downward trend was observed for partial-thickness tears. Sensitivity and specificity were 0.95 and 0.79, respectively, for third-year residents and 0.91 and 0.58, respectively, for second-year residents. Residents reported self-confidence after 30 ultrasound scans for the detection of rotator cuff tears. Conclusions The number of scans that novices needed to be competent for detecting rotator cuff tears was approximately 30 cases, and the diagnostic accuracy of third-year residents was significantly higher than that of second-year residents.

Purpose: We investigated whether response classification after total thyroidectomy and radioactive iodine (RAI) therapy could be affected by serum levels of recombinant human thyrotropin (rhTSH)-stimulated thyroglobulin (Tg) measured at different time points in a follow-up of patients with papillary thyroid carcinoma (PTC). Methods: A total of 147 PTC patients underwent serum Tg measurement for response assessment 6 to 24 months after the first RAI therapy. Serum Tg levels were measured at 24 h (D1Tg) and 48–72 h (D2-3Tg) after the 2nd injection of rhTSH. Responses were classified into three categories based on serum Tg corresponding to the excellent response (ER-Tg), indeterminate response (IR-Tg), and biochemical incomplete response (BIR-Tg). The distribution pattern of response classification based on serum Tg at different time points (D1Tg vs. D2-3Tg) was compared. Results: Serum D2-3Tg level was higher than D1Tg level (0.339 ng/mL vs. 0.239 ng/mL, P < 0.001). The distribution of response categories was not significantly different between D1Tg-based and D2-3Tg-based classification. However, 8 of 103 (7.8%) patients and 3 of 40 (7.5%) patients initially categorized as ER-Tg and IR-Tg based on D1Tg, respectively, were reclassified to IR-Tg and BIR-Tg based on D2-3Tg, respectively. The optimal cutoff values of D1Tg for the change of response categories were 0.557 ng/mL (from ER-Tg to IR-Tg) and 6.845 ng/mL (from IR-Tg to BIR-Tg). Conclusion D1Tg measurement was sufficient to assess the therapeutic response in most patients with low level of D1Tg. Nevertheless, D2-3Tg measurement was still necessary in the patients with D1Tg higher than a certain level as response classification based on D2-3Tg could change.

Background: There is currently a lack of evidence-based postresuscitation or postmortem guidelines for patients with out-of-hospital cardiac arrest (OHCA) in the setting of an emerging infectious disease. This study aimed to develop and validate a multimodal screening tool that aids in predicting the disease confirmation in emergency situations and patients with OHCA during a coronavirus disease 2019 (COVID-19) outbreak. Materials and Methods: We conducted a retrospective, multicenter observational study of adult patients with OHCA in Daegu, Korea. To identify the potential predictors that could be used in screening tools in the emergency department, we applied logistic regression to data collected from March 1 to March 14. The prediction performance of the screening variables was then assessed and validated on the data of patients with OHCA who were treated between February 19 and March 31, 2020. General patient characteristics and hematological findings of the COVID-19-negative and COVID-19-positive groups were compared. We also evaluated confirmation test criteria as predictors for COVID-19 positivity in patients with OHCA. Results: Advanced age, body temperature, and abnormal chest X-ray (CXR) revealed significant predictive ability in the derivation cohort. Of the 184 adult patients with OHCA identified in the validation cohort, 80 patients were included in the analysis. Notably, 9 patients were positive and 71 were negative on the COVID-19 reverse transcription polymerase chain reaction test. Five patients (55.6%) in the COVID-19-positive group had a fever before OHCA, and 12 (16.9%) of the COVID-19-negative group had a fever before OHCA (P = 0.018).Eight patients (88.9%) in the COVID-19-positive group had a CXR indicating pneumonic infiltration. Of the criteria for predicting COVID-19, fever or an abnormal CXR had a sensitivity of 100% (95% confidence interval [CI]: 65.4 – 100) and a specificity of 22.5% (95% CI: 13.5 – 34.0). Conclusion The screening tools that combined fever or abnormal CXR had a good discriminatory ability for COVID-19 infection in adult patients with OHCA. Therefore, during the COVID-19 outbreak period, it is recommended to suspect COVID-19 infection and perform COVID-19 test if patients present with a history of fever or show abnormal findings in postmortem CXR

Objective: This study compared the prognostic performance of the following five injury severity scores: the Geriatric Trauma Outcome Score (GTOS), the Injury Severity Score (ISS), the New Injury Severity Score (NISS), the Revised Trauma Score (RTS), and the Trauma and Injury Severity Score (TRISS) for in-hospital mortality in severe geriatric trauma patients. Methods: A retrospective, cross-sectional, observational study was conducted using a database of severe geriatric trauma patients (age ≥65 years and ISS ≥16) who presented to a single regional trauma center between November 2016 and October 2018. We compared the baseline characteristics between the survivor and mortality groups and the predictive ability of the five scoring systems. Results: A total of 402 patients were included in the analysis; the in-hospital mortality rate was 25.6% (n=103). The TRISS had the highest area under the curve of 0.953 (95% confidence interval [CI], 0.927-0.971); followed by RTS, 0.777 (95% CI, 0.733-0.817); NISS, 0.733 (95% CI, 0.687-0.776); ISS, 0.660 (95% CI, 0.612-0.707); and GTOS, 0.660 (95% CI, 0.611-0.706) in severe geriatric trauma. The TRISS also had the highest area under the curve of 0.961 (0.919-0.985) among the injury severity scoring systems in polytrauma. The predictive ability of TRISS was significantly higher than the other four scores with respect to overall trauma and polytrauma (P<0.001). Conclusion The TRISS showed the highest prognostic performance for predicting in-hospital mortality among all the injury severity scoring systems in severe geriatric trauma.

Background: There is currently a lack of evidence-based postresuscitation or postmortem guidelines for patients with out-of-hospital cardiac arrest (OHCA) in the setting of an emerging infectious disease. This study aimed to develop and validate a multimodal screening tool that aids in predicting the disease confirmation in emergency situations and patients with OHCA during a coronavirus disease 2019 (COVID-19) outbreak. Materials and Methods: We conducted a retrospective, multicenter observational study of adult patients with OHCA in Daegu, Korea. To identify the potential predictors that could be used in screening tools in the emergency department, we applied logistic regression to data collected from March 1 to March 14. The prediction performance of the screening variables was then assessed and validated on the data of patients with OHCA who were treated between February 19 and March 31, 2020. General patient characteristics and hematological findings of the COVID-19-negative and COVID-19-positive groups were compared. We also evaluated confirmation test criteria as predictors for COVID-19 positivity in patients with OHCA. Results: Advanced age, body temperature, and abnormal chest X-ray (CXR) revealed significant predictive ability in the derivation cohort. Of the 184 adult patients with OHCA identified in the validation cohort, 80 patients were included in the analysis. Notably, 9 patients were positive and 71 were negative on the COVID-19 reverse transcription polymerase chain reaction test. Five patients (55.6%) in the COVID-19-positive group had a fever before OHCA, and 12 (16.9%) of the COVID-19-negative group had a fever before OHCA (P = 0.018).Eight patients (88.9%) in the COVID-19-positive group had a CXR indicating pneumonic infiltration. Of the criteria for predicting COVID-19, fever or an abnormal CXR had a sensitivity of 100% (95% confidence interval [CI]: 65.4 – 100) and a specificity of 22.5% (95% CI: 13.5 – 34.0). Conclusion The screening tools that combined fever or abnormal CXR had a good discriminatory ability for COVID-19 infection in adult patients with OHCA. Therefore, during the COVID-19 outbreak period, it is recommended to suspect COVID-19 infection and perform COVID-19 test if patients present with a history of fever or show abnormal findings in postmortem CXR

Objective: This study compared the prognostic performance of the following five injury severity scores: the Geriatric Trauma Outcome Score (GTOS), the Injury Severity Score (ISS), the New Injury Severity Score (NISS), the Revised Trauma Score (RTS), and the Trauma and Injury Severity Score (TRISS) for in-hospital mortality in severe geriatric trauma patients. Methods: A retrospective, cross-sectional, observational study was conducted using a database of severe geriatric trauma patients (age ≥65 years and ISS ≥16) who presented to a single regional trauma center between November 2016 and October 2018. We compared the baseline characteristics between the survivor and mortality groups and the predictive ability of the five scoring systems. Results: A total of 402 patients were included in the analysis; the in-hospital mortality rate was 25.6% (n=103). The TRISS had the highest area under the curve of 0.953 (95% confidence interval [CI], 0.927-0.971); followed by RTS, 0.777 (95% CI, 0.733-0.817); NISS, 0.733 (95% CI, 0.687-0.776); ISS, 0.660 (95% CI, 0.612-0.707); and GTOS, 0.660 (95% CI, 0.611-0.706) in severe geriatric trauma. The TRISS also had the highest area under the curve of 0.961 (0.919-0.985) among the injury severity scoring systems in polytrauma. The predictive ability of TRISS was significantly higher than the other four scores with respect to overall trauma and polytrauma (P<0.001). Conclusion The TRISS showed the highest prognostic performance for predicting in-hospital mortality among all the injury severity scoring systems in severe geriatric trauma.

Purpose: We investigated the clinical role of F-18 fluorodeoxyglucose (FDG) positron emission tomography-computed tomography(PET-CT) in the identification of the primary site and the selection of the optimal biopsy site in patients with suspectedbone metastasis of unknown primary site. Methods: The patients with suspected bone metastasis who underwent PET-CT for evaluation of primary site were enrolled inthis study. The primary sites were identified by the histopathologic or imaging studies and were classified according to the FDGuptake positivity of the primary site. To evaluate the guiding capability of PET-CT in biopsy site selection, we statisticallyanalyzed whether the biopsy site could be affected according to the presence of extra-skeletal FDG uptake. Results: Among 74 enrolled patients, 51 patients had a metastatic bone disease. The primary site was identified in 48 of 51patients (94.1%). Forty-six patients were eligible to test the association of clinical choice of biopsy site with PET positivity ofextra-skeletal lesion. The extra-skeletal biopsies were done in 42 out of 43 patients with positive extra-skeletal uptake lesions.Bone biopsies were inevitably performed in the other three patients without extra-skeletal uptake lesions. The association cameout to be significant (Fisher’s exact test, P< 0.001). Conclusion F-18 FDG PET-CT significantly contributed not only to identify the primary site but also to suggest optimal biopsysites in patients with suspected bone metastasis.