A novel 3D MRI-based approach for assessing supraspinatus muscle length.

Rotator cuff (RC) tears are a common source of pain and decreased shoulder strength. Muscle length is known to affect muscle strength, and therefore evaluating changes in supraspinatus muscle length associated with RC pathology, surgical repair, and post-operative recovery may provide insights into functional deficits. Our objective was to develop a reliable MRI-based approach for assessing supraspinatus muscle length. Using a new semi-automated approach for identifying 3D location of the muscle-tendon junction (MTJ), supraspinatus muscle length was calculated as the sum of MTJ distance (distance between 3D MTJ position and glenoid plane) and supraspinatus fossa length (distance between root of the scapular spine and glenoid plane). Inter- and intra-operator reliability of this technique were assessed with intraclass correlation coefficient (ICC) and found to be excellent (ICCs > 0.96). Muscle lengths of 6 patients were determined before RC repair surgery and at 3- and 12-months post-surgery. Changes in normalized muscle length (muscle length as a percentage of pre-surgical muscle length) at 3 months post-surgery varied considerably across patients (16.1 % increase to 7.0 % decrease) but decreased in all patients from 3- to 12-months post-surgery (0.3 % to 17.2 %). This study developed a novel and reliable approach for quantifying supraspinatus muscle length and provided preliminary demonstration of its utility by assessing muscle length changes associated with RC pathology and surgical repair. Future studies can use this technique to evaluate changes over time in supraspinatus muscle length in response to clinical intervention, and associations between muscle length and shoulder function.

Elbow Torque Is Reduced in Asymptomatic College Pitchers With Elbow Laxity: A Dynamic Ultrasound Study.

PURPOSE: To determine the relation between medial elbow torque, as measured by wearable sensor technology, and adaptations of the medial elbow structures on dynamic ultrasound imaging in asymptomatic collegiate pitchers. METHODS: Thirty-four pitchers from National Collegiate Athletic Association Division II universities were eligible for preseason testing. The exclusion criteria included age younger than 18 years, history of surgery, non-pitcher, or current restrictions. Pitchers were fitted with a wearable sensor sleeve that recorded elbow torque, arm slot, arm speed, and arm rotation. Pitchers threw 5 fastballs in a standardized manner off the mound at game-speed effort. They also underwent dynamic ultrasound imaging of the elbow by a musculoskeletal sonographer, with standardized valgus loading. Images were deidentified, and measurements of the ulnar collateral ligament (UCL) and ulnohumeral joint space (UHJS), to assess elbow laxity, were performed by a musculoskeletal radiologist. RESULTS: The final analysis included 28 pitchers with an average age of 20.1 years (standard deviation, 1.3 years; range, 18-23 years) and playing experience of 15.3 years (standard deviation, 1.8 years; range, 11-19 years). The dominant UCL thickness (P < .001), loaded UHJS (P = .039), and delta UHJS (P < .001) were significantly greater than the nondominant measurements. An inverse correlation was found between loaded UHJS and medial elbow torque (r = -0.4, P < .001). Additionally, every 1-mm increase in UHJS significantly reduced medial elbow torque by 2.27 Nm (P = .032) and arm slot by 8.8° (P = .019) and increased arm rotation by 5.3° (P = .043). Pitchers with a loaded UHJS of 4.4 mm or greater and delta UHJS of 1.25 mm or greater had significantly reduced medial elbow torque (P < .001). Pitchers with a UCL thickness of 1.65 mm or greater had significantly increased medial elbow torque (47.4 Nm vs 44.8 Nm, P = .006). CONCLUSIONS: Pitchers with increased dynamic elbow laxity were found to experience reduced medial elbow torque while pitching. Additionally, pitchers with greater UCL thickness on ultrasound were found to experience increased medial elbow torque while pitching. This study's findings suggest a relation between anatomic adaptations found on ultrasound of the pitching elbow and medial elbow torque. LEVEL OF EVIDENCE: Level II, prospective cohort study.

Incidental findings detected on preoperative CT imaging obtained for robotic-assisted joint replacements: clinical importance and the effect on the scheduled arthroplasty.

OBJECTIVE: To determine the type and frequency of incidental findings detected on preoperative computed tomography (CT) imaging obtained for robotic-assisted joint replacements and their effect on the planned arthroplasty. MATERIALS AND METHODS: All preoperative CT examinations performed for a robotic-assisted knee or total hip arthroplasty were obtained. This resulted in 1432 examinations performed between September 2016 and February 2020 at our institution. These examinations were initially interpreted by 1 of 9 fellowship-trained musculoskeletal radiologists. Using a diagnosis search, the examination reports were then reviewed to catalog all incidental findings and further classify as significant or non-significant findings. Demographic information was obtained. In those with significant findings, a chart review was performed to record the relevant workup, outcomes, and if the planned arthroplasty was affected. RESULTS: Incidental findings were diagnosed in 740 (51.7%) patients. Of those with incidental findings, 41 (5.5%) were considered significant. A significant finding was more likely to be detected in males (P = 0.007) and on the hip protocol CT (P = 0.014). In 8 patients, these diagnoses resulted in either delay or cancelation of the arthroplasty. A planned total hip arthroplasty was more likely to be altered as compared to a knee arthroplasty (P = 0.018). CONCLUSION: Incidental findings are commonly detected by radiologists on preoperative CT imaging obtained for robotic-assisted joint replacement. Several were valuable findings and resulted in a delay or even cancelation of the planned arthroplasty after the detection of critical diagnoses, which if not identified may have resulted in devastating outcomes.

Impact of the COVID-19 pandemic on radiology physician work RVUs at a large subspecialized radiology practice.

PURPOSE: As the COVID-19 pandemic continues, efforts by radiology departments to protect patients and healthcare workers and mitigate disease spread have reduced imaging volumes. This study aims to quantify the pandemic's impact on physician productivity across radiology practice areas as measured by physician work Relative Value Units (wRVUs). MATERIALS AND METHODS: All signed diagnostic and procedural radiology reports were curated from January 1st to July 1st of 2019 and 2020. Physician work RVUs were assigned to each study type based on the Medicare Physician Fee Schedule. Utilizing divisional assignments, radiologist schedules were mapped to each report to generate a sum of wRVUs credited to that division for each week. Differential impact on divisions were calculated relative to a matched timeframe in 2019 and a same length pre-pandemic time period in 2020. RESULTS: All practice areas saw a substantial decrease in wRVUs from the 2020 pre- to intra-pandemic time period with a mean decrease of 51.5% (range 15.4%-76.9%). The largest declines were in Breast imaging, Musculoskeletal, and Neuroradiology, which had decreases of 76.9%, 75.3%, and 67.5%, respectively. The modalities with the greatest percentage decrease were mammography, MRI, and non-PET nuclear medicine. CONCLUSION: All radiology practice areas and modalities experienced a substantial decrease in wRVUs. The greatest decline was in Breast imaging, Neuroradiology, and Musculoskeletal radiology. Understanding the differential impact of the pandemic on practice areas will help radiology departments prepare for the potential depth and duration of the pandemic by better understanding staffing needs and the financial effects.

COVID-19 and Radiology Resident Imaging Volumes-Differential Impact by Resident Training Year and Imaging Modality.

RATIONALE AND OBJECTIVES: The COVID-19 pandemic has greatly impacted radiology departments across the country. The pandemic has also disrupted resident education, both due to departmental social distancing efforts and reduced imaging volumes. The purpose of this study was to assess the differential impact the pandemic had on radiology resident imaging volumes by training year and imaging modality. MATERIALS AND METHODS: All signed radiology resident reports were curated during defined prepandemic and intrapandemic time periods. Imaging case volumes were analyzed on a mean per resident basis to quantify absolute and percent change by training level. Change in total volume by imaging modality was also assessed. The number of resident workdays assigned outside the normal reading room was also calculated. RESULTS: Overall percent decline in resident imaging interpretation volume from the prepandemic to intrapandemic time period was 62.8%. R1s and R2s had the greatest decline at 87.3% and 64.3%, respectively. Mammography, MRI and nuclear medicine had the greatest decline in resident interpretation volume at 92.0%, 73.2%, and 73.0%, respectively. During the intrapandemic time period, a total of 478 resident days (mean of 14.5 days per resident) were reassigned outside of the radiology reading room. CONCLUSION: The COVID-19 pandemic caused a marked decrease in radiology resident imaging interpretation volume and has had a tremendous impact on resident education. The decrease in case interpretation, as well as in-person teaching has profound implications for resident education. Knowledge of this differential decrease by training level will help residency programs plan for the future.