Medial Meniscal Extrusion Evaluation With Weight-Bearing Ultrasound: Correlation With MR Imaging Findings and Reported Symptoms: Correlation With MR Imaging Findings and Reported Symptoms.

OBJECTIVES: To compare medial meniscal extrusion on weight-bearing ultrasound (US) with supine US and magnetic resonance (MR) imaging correlating with meniscal pathology and reported symptoms. METHODS: IRB approved study with informed consent. Patients obtaining routine knee MR imaging for suspected knee pathology were prospectively evaluated with supine and weight-bearing US of the medial meniscus. Meniscal extrusion was measured independently by two fellowship-trained musculoskeletal radiologists. Correlation was made to presence or absence of meniscal degeneration or tear on MR imaging, as well as reported symptoms. Statistical significance was calculated via intraclass correlation coefficient (ICC) and analysis of variance (ANOVA). RESULTS: Ninety-nine knees from 95 subjects (50 males, 45 females; mean age 45 ± 15 years) were included. Mean medial meniscal extrusion measured at US for a normal meniscus (n = 36) was 0.8 mm when supine, increasing to 1.6 mm on weight-bearing. Mean meniscal extrusion in subjects with mucoid degeneration (n = 20) and those with meniscal tears (n = 43) was 1.6 mm, increasing to 2.3 mm with weight bearing. Inter-reader reliability showed ICC values of 0.853 to 0.940. There was a significant difference in medial meniscal extrusion comparing subjects with a normal medial meniscus at magnetic resonance imaging (MRI) and subjects with either meniscal degeneration or tear. There was no significant difference in degree of meniscal extrusion between subjects with meniscal degeneration or tear. There was trend of worsening symptoms and increasing functional limitations moving from normal meniscus to meniscal degeneration to meniscal tear. CONCLUSIONS: A normal meniscus shows lesser mobility between supine and upright position, than a pathologic meniscus. Both mucoid degeneration and meniscal tear demonstrate extrusion in the supine position, which increases with weight-bearing position.

Improving MR Image Quality in Patients with Metallic Implants.

The number of implanted devices such as orthopedic hardware and cardiac implantable devices continues to increase with an increase in the age of the patient population, as well as an increase in the number of indications for specific devices. Many patients with these devices have or will develop clinical conditions that are best depicted at MRI. However, implanted devices containing paramagnetic or ferromagnetic substances can cause significant artifact, which could limit the diagnostic capability of this modality. Performing imaging with MRI when an implant is present may be challenging, and there are numerous techniques the radiologist and technologist can use to help minimize artifacts related to implants. First, knowledge of the presence of an implant before patient arrival is critical to ensure safety of the patient when the device is subjected to a strong magnetic field. Once safety is ensured, the examination should be performed with the MRI system that is expected to provide the best image quality. The selection of the MRI system includes multiple considerations such as the effects of field strength and availability of specific sequences, which can reduce metal artifact. Appropriate patient positioning, attention to MRI parameters (including bandwidth, voxel size, and echo), and appropriate selection of sequences (those with less metal artifact and advanced metal reduction sequences) are critical to improve image quality. Patients with implants can be successfully imaged with MRI with appropriate planning and understanding of how to minimize artifacts. This improves image quality and the diagnostic confidence of the radiologist. ©RSNA, 2021.

The effect of age when initiating anti-seizure medication therapy on fragility fracture risk for children with epilepsy.

BACKGROUND: Anti-seizure medication (ASM) is necessary to manage epilepsy and often prescribed to children and adolescents, but can lead to iatrogenic effects, including bone fragility by altering bone metabolism. Disrupting bone metabolism during crucial developmental stages could have a lasting adverse effect on bone health. Therefore, the objective of this propensity score-matched, observational cohort study was to determine if age when initiating ASM therapy across developmental stages (from pre- to post-puberty) for individuals with epilepsy was associated with an increased risk of fragility fracture. METHODS: Data from 01/01/2011 to 12/31/2018 were extracted from Optum Clinformatics® Data Mart. Children aged 4-21 years at baseline with at least 5 years of continuous health plan enrollment were included to allow for a 1-year baseline and 4-years of follow-up. The primary group of interest included new ASM users (i.e., treatment naïve) with epilepsy. The comparison group, no ASM users without epilepsy, was matched 1:14 to new ASM users with epilepsy for demographics and baseline fracture. To provide a proxy for developmental stages, age was categorized as 4-6 (pre-puberty), 7-10 (early puberty), 11-13 (mid-puberty), 14-17 (late puberty), and 18-21 (post-puberty). Crude incidence rate (IR; per 1000 person years) and IR ratio (IRR and 95% confidence intervals [CI]) were estimated for non-trauma fracture (NTFx) for up to 4-years of follow-up. RESULTS: Prior to stratifying by age group, the crude NTFx IR (95% CI) of 20.6 (16.5-24.8) for new ASM users with epilepsy (n = 1205) was 34% higher (IRR = 1.34; 95% CI = 1.09-1.66) than the crude NTFx IR (95% CI) of 15.4 (14.4-16.3) for no ASM users without epilepsy. The groups exhibited a different pattern of NTFx incidence with age, with new ASM users showing a more dramatic increase and peaking at 11-13 years, then decreasing with the older age groups. The crude IR and IRR were elevated for new ASM users with epilepsy compared to no ASM users without epilepsy for each age group (10% to 55% higher), but was only statistically significant for 11-13 years (IRR = 1.55; 95% CI = 1.02-2.36). CONCLUSIONS: Children with epilepsy initiating ASM therapy may be vulnerable to fragility fracture, especially when initiating ASM around the time of puberty. Clinicians should be aware of this age-related association and consider age-appropriate adjunct bone fragility therapies.

MR imaging of the quadriceps femoris tendon: distal tear characterization and clinical significance of rupture types.

OBJECTIVE: To characterize quadriceps femoris tendon tears on magnetic resonance (MR) imaging regarding tear extent, location, and presence of bony avulsion. MATERIALS AND METHODS: IRB approval was obtained and informed consent was waived for this retrospective case series. Electronic medical records from all patients in our hospital system were searched for keywords: knee MR imaging, and quadriceps tendon rupture or tear. MRI studies were randomized and independently evaluated by two fellowship-trained musculoskeletal radiologists. MR imaging was used to characterize each individual quadriceps tendon as having tendinosis, tear (location, partial versus complete, size, and retraction distance), and bony avulsion. Knee radiographs were reviewed for presence or absence of bony avulsion. Descriptive statistics and inter-reader reliability (Cohen's Kappa and Wilcoxon-signed-rank test) were calculated. RESULTS: Fifty-two patients with 53 quadriceps tears were evaluated (45 males, 7 females; mean age: 51 ± 13 years). The vastus intermedius (VI) tendon more often incurred a partial rather than a complete tear (39.6% vs. 37.7%), while the rectus femoris (RF), vastus medialis (VM), and vastus lateralis (VL) incurred complete tears more commonly (64.2-66%). Subjects with bony avulsion on radiographs had higher-grade tears of the RF, VM, and VL tears (p = 0.020-0.043) but not the VI. Most tendons tore at or immediately proximal to the patella (84.8-93.6%). Gaps in retracted torn tendons measured between 2.3 and 2.7 cm. Inter-reader reliability was substantial to almost perfect (κ = 0.624-0.953). CONCLUSION: Quadriceps femoris tendon tears most commonly involve the RF or VL/VM layers usually in proximity to the patella. A bony avulsion correlates with a more extensive tear. KEY POINTS: • Quadriceps femoris tendon tears most commonly involve the rectus femoris or vastus lateralis/vastus medialis layers. • A rupture of the quadriceps femoris tendon usually occurs in proximity to the patella. • A bony avulsion of the patella correlates with a more extensive tear of the superficial and middle layers of the quadriceps tendon.

Preoperative Grades of Osteoarthritis and Meniscus Volume Correlate with Clinical Outcomes of Osteochondral Graft Treatment for Cartilage Defects in the Knee.

OBJECTIVE: To identify preoperative imaging-based indicators of knee degeneration that correlate with graft failure risk and postoperative clinical outcome scores after osteochondral graft treatment for chondral defects of the knee. DESIGN: Prospectively collected data from 113 patients (mean age, 34 years; 65% male) treated with mosaicplasty or osteochondral allograft transplantation (OCA) was reviewed. Four different aspects of knee degeneration were examined based on preoperative radiographs or magnetic resonance imaging: (1) Osteoarthritis using the Kellgren-Lawrence (KL) grading system, (2) meniscus volume, (3) meniscus quality, and (4) synovitis. Primary outcomes included graft failure, defined by removal/revision of the graft or conversion to arthroplasty, and patient responses to clinical outcome scores. RESULTS: Forty-one knees (36%) underwent mosaicplasty, and 72 knees (64%) underwent OCA. Mean duration of follow-up was 4.5 years (range, 2-14 years). A preoperative KL grade of ≥3 was correlated with increased failure rates (P = 0.01), lower postoperative International Knee Documentation Committee form (IKDC), Activities of Daily Living of the Knee Outcome Survey (KOS-ADL), and Overall Condition scores (P < 0.01), and decreased improvement in Overall Condition scores (P = 0.01). Within an individual tibiofemoral compartment, a preoperative meniscus volume grade of ≥3 (indicating <50% meniscus volume remaining) was correlated with increased condylar graft failure rates (P < 0.01). Preoperative meniscus quality and synovitis grades were not associated with graft failure rates or clinically meaningful differences in postoperative outcome scores. CONCLUSIONS: Greater preoperative osteoarthritis and meniscus volume loss were correlated with increased graft failure rates after osteochondral graft treatment for chondral defects of the knee.

Osseous Healing With Nonrigid Suture Fixation in the Arthroscopic Latarjet Procedure.

BACKGROUND: The Latarjet procedure is a popular means to surgically address anterior glenohumeral joint instability. Although the Latarjet procedure is becoming increasingly common, challenges persist and include postoperative complications secondary to use of the conventional 2 bicortical fixation screws. Recently, a novel surgical technique using a guided surgical approach for graft positioning with nonrigid fixation via a suture suspensory system has been described. PURPOSE: To evaluate healing rates and stability of the grafts in patients who underwent this new Latarjet technique. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: We retrospectively gathered anonymized computed tomography (CT) data sets from a total of 107 patients who underwent nonrigid suture fixation using a cortical button fixation for anterior glenohumeral instability. Of the 107 patients, 45 had CT scans performed at 2 different time periods. The CT scans of each patient were compared by 2 fellowship-trained musculoskeletal radiologists. Data recorded included age, sex, date of scan, initial graft position on the glenoid, presence and degree of graft migration relative to the equator on follow-up scan, and percentage of osseous healing (as assessed by osseous bridging) on the follow-up scan. Descriptive statistics were calculated to evaluate the average migration and average percentage of healing at both time points. RESULTS: Our population (n = 45) consisted of 38 men (84.4%) and 7 women (15.6%). The mean age was 27.1 ± 1.1 years. The mean time between initial CT scan (2 weeks postoperatively) and follow-up CT scan was 26 ± 2 weeks. On follow-up scan, reviewer 1 found 75.6% of patients had greater than 75% healing, and reviewer 2 found 70.2% of patients had greater than 75% healing. The center of the graft was measured at or below the equator on follow-up examination in 43 of 45 (95.6%) patients by reviewer 1 and 44 of 45 (97.8%) patients by reviewer 2. CONCLUSION: Based on these findings, nonrigid suture fixation using a cortical button device offers an effective alternative to traditional screw fixation for the Latarjet procedure with a high level of osseous healing and minimal graft migration.

The influence of patient race on the use of diagnostic imaging in United States emergency departments: data from the National Hospital Ambulatory Medical Care survey.

BACKGROUND: An established body of literature has shown evidence of implicit bias in the health care system on the basis of patient race and ethnicity that contributes to well documented disparities in outcomes. However, little is known about the influence of patient race and ethnicity on the decision to order diagnostic radiology exams in the acute care setting. This study examines the role of patient race and ethnicity on the likelihood of diagnostic imaging exams being ordered during United States emergency department encounters. METHODS: Publicly available data from the National Hospital Ambulatory Medical Care Survey Emergency Department sample for the years 2006-2016 was compiled. The proportion of patient encounters where diagnostic imaging was ordered was tabulated by race/ethnicity, sub-divided by imaging modality. A multivariable logistic regression model was used to evaluate the influence of patient race/ethnicity on the ordering of diagnostic imaging controlling for other patient and hospital characteristics. Survey weighting variables were used to formulate national-level estimates. RESULTS: Using the weighted data, an average of 131,558,553 patient encounters were included each year for the 11-year study period. Imaging was used at 46% of all visits although this varied significantly by patient race and ethnicity with white patients receiving medical imaging at 49% of visits and non-white patients at 41% of visits (p < 0.001). This effect persisted in the controlled regression model and across all imaging modalities with the exception of ultrasound. Other factors with a significant influence on imaging use included patient age, gender, insurance status, number of co-morbidities, hospital setting (urban vs non-urban) and hospital region. There was no evidence to suggest that the disparate use of imaging by patient race and ethnicity changed over the 11-year study time period. CONCLUSION: The likelihood that a diagnostic imaging exam will be ordered during United States emergency department encounters differs significantly by patient race and ethnicity even when controlling for other patient and hospital characteristics. Further work must be done to understand and mitigate what may represent systematic bias and ensure equitable use of health care resources.

COVID-19 Impact on Well-Being and Education in Radiology Residencies: A Survey of the Association of Program Directors in Radiology.

RATIONALE AND OBJECTIVES: The COVID-19 pandemic has forced rapid evolution of the healthcare environment. Efforts to mitigate the spread of the virus through social distancing and shelter-at-home edicts have unintended consequences upon clinical and educational missions and mental well-being of radiology departments. We sought to understand the impact of the COVID-19 pandemic on radiology residencies with respect to the educational mission and perceptions of impact on well-being. MATERIALS AND METHODS: This study was IRB exempt. An anonymous 22 question survey regarding the impact of COVID-19 pandemic on educational and clinical missions of residencies, its perceived impact upon morale of radiologists and trainees and a query of innovative solutions devised in response, was emailed to the Association of Program Directors in Radiology membership. Survey data were collected using SurveyMonkey (San Mateo, California). RESULTS: Respondents felt the COVID-19 pandemic has negatively impacted their residency programs. Regarding the educational mission impact, 70.1% (75/107) report moderate/marked negative impact and 2.8% (3/107) that educational activities have ceased. Regarding the pandemic's impact on resident morale, 44.8% (48/107) perceive moderate/marked negative effect; perceived resident morale in programs with redeployment is significantly worse with 57.1% (12/21) reporting moderate/marked decrease. Respondents overwhelmingly report adequate resident access to mental health resources during the acute phase of the pandemic (88.8%, 95/107). Regarding morale of program directors, 61% (65/106) report either mild or marked decreased morale. Program innovations reported by program directors were catalogued and shared. CONCLUSION: The COVID-19 pandemic has markedly impacted the perceived well-being and educational missions of radiology residency programs across the United States.

Cartilage icing and chondrocalcinosis on knee radiographs in the differentiation between gout and calcium pyrophosphate deposition.

OBJECTIVE: To determine if findings of "cartilage icing" and chondrocalcinosis on knee radiography can differentiate between gout and calcium pyrophosphate deposition (CPPD). METHODS: IRB-approval was obtained and informed consent was waived for this retrospective study. Electronic medical records from over 2.3 million patients were searched for keywords to identify subjects with knee aspiration-proven cases of gout or CPPD. Radiographs were reviewed by two fellowship-trained musculoskeletal radiologists in randomized order, blinded to the patients' diagnoses. Images were evaluated regarding the presence or absence of cartilage icing, chondrocalcinosis, tophi, gastrocnemius tendon calcification, and joint effusion. Descriptive statistics, sensitivity, specificity, positive and negative predictive values, and accuracy were calculated. RESULTS: From 49 knee radiographic studies in 46 subjects (31 males and 15 females; mean age 66±13 years), 39% (19/49) showed gout and 61% (30/49) CPPD on aspiration. On knee radiographs, cartilage icing showed a higher sensitivity for CPPD than gout (53-67% and 26%, respectively). Chondrocalcinosis also showed a higher sensitivity for CPPD than gout (50-57% versus 5%), with 95% specificity and 94% positive predictive value for diagnosis of CPPD versus gout. Soft tissue tophus-like opacities were present in gout at the patellar tendon (5%, 1/19) and at the popliteus groove in CPPD (15%, 4/27). Gastrocnemius tendon calcification was present in 30% (8/27) of subjects with CPPD, and 5% (1/19) of gout. CONCLUSION: In subjects with joint aspiration-proven crystal disease of the knee, the radiographic finding of cartilage icing was seen in both gout and CPPD. Chondrocalcinosis (overall and hyaline cartilage) as well as gastrocnemius tendon calcification positively correlated with the diagnosis of CPPD over gout.

Ultrasound characterization of pseudoerosions and dorsal joint recess morphology of the hand and wrist in 100 asymptomatic subjects.

PURPOSE: To sonographically characterize pseudoerosions and dorsal joint recess and capsule morphology of the hand and wrist in 100 asymptomatic subjects. METHOD: The metacarpal heads, and dorsal aspects of the lunate, triquetrum, and ulna were evaluated for pseudoerosions including measurements and sonographic characterization. The dorsal recesses of the metacarpophalangeal, radiocarpal, and midcarpal joints were also characterized with regards to echogenicity, fibrillar pattern, hyperemia, and measurements. RESULTS: 100 subjects were included (average age 47 years, range 19-82 years; 52% male, 48% female). Pseudoerosions of metacarpophalangeal heads were seen in every subject, in all metacarpal heads, but most commonly the second and third (99% were bilateral, 97% were multiple); 81.5% involved at least three metacarpal heads; 99% were central with maximum depth of 2.6 mm. At the wrist, in 92% of subjects a bilateral pseudoerosion was present at the dorsal triquetrum, lunate, or ulna. Dorsal joint capsules and recesses at the metacarpophalangeal joints were isoechoic to subdermal fat and fibrillar measuring 3.1-6.3 mm in maximal thickness. The dorsal capsules and recesses of the radiocarpal and midcarpal joints were hypoechoic to subdermal fat, non-fibrillar and with maximal thickness of 3.9 and 3.4 mm, respectively. No hyperemia on color Doppler imaging was noted. CONCLUSIONS: Pseudoerosions are common at the dorsal metacarpal heads, lunate, triquetrum, and ulna, which should not be mistaken for true inflammatory erosions. The characteristic appearances of dorsal joint capsules and recesses should not be confused with synovial hypertrophy.

Hand-Held Portable Versus Conventional Cart-Based Ultrasound in Musculoskeletal Imaging.

BACKGROUND: Portable ultrasound machines are now common, used for point-of-care applications and needle guidance for percutaneous procedures; however, the effectiveness of portable ultrasound in evaluation of the musculoskeletal system has not been fully assessed. PURPOSE: To prospectively evaluate the use of portable hand-held ultrasound in comparison with conventional cart-based ultrasound in evaluation of the musculoskeletal system. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 2. METHODS: In this institutional review board-approved, prospective study, 100 consecutive patients with informed consent were imaged through use of both portable and cart-based ultrasound equipment using 12-5 MHz linear transducers. Agreement in ultrasound diagnosis was documented along with expected clinical changes in management if there was disagreement (definitely no, probably no, uncertain, probably yes, definitely yes). Imaging details of disagreement cases were recorded, and descriptive statistics were calculated. RESULTS: There were 42 male and 58 female patients (mean ± SD age, 53 ± 13 years) imaged over a time period of 20 months. Anatomic areas scanned were the shoulder (n = 30), elbow (n = 11), hand and wrist (n = 15), hip (n = 10), knee (n = 11), foot and ankle (n = 12), and others (n = 11). Scanning with conventional ultrasound revealed abnormality in 92% of patients. Agreement in diagnosis made between portable versus cart-based ultrasound was found in 65% of patients. In the 35% of patients with discordant results, the change in diagnosis resulted in no change in clinical management in 46%, probably no change in 29%, uncertain change in 14%, probable change in 11%, and definite change in 0%. The diagnoses changing management (4%; 4/100) included nondetection of a satellite nodule (n = 1), ganglion cyst (n = 1), hernia (n = 1), and underestimated tendon tear (n = 1). CONCLUSION: When compared with conventional cart-based ultrasound, a musculoskeletal diagnosis using portable hand-held ultrasound was concordant or was discordant without clinical relevance in 96% (96/100) of patients. Knowledge of benefits and limitations of portable hand-held ultrasound will help determine areas where specific types of ultrasound equipment can be used.

Common Causes of Outpatient CT and MRI Callback Examinations: Opportunities for Improvement.

OBJECTIVE. The purposes of this study were to investigate factors driving callback MRI and CT examinations and to discern opportunities for optimizing the patient experience by reducing future callbacks. MATERIALS AND METHODS. All consecutive outpatient CT and MRI callback examinations from October 2015 to October 2017 in four radiology subspecialties (cardiothoracic imaging, abdominal imaging, neuroradiology, musculoskeletal imaging) were reviewed at an academic quaternary care center. Callback details (modality, subspecialty, protocoling radiologist, protocol assigned, protocol performed, interpreting radiologist, and reason for callback) were recorded, and reason for callback was categorized. Callback rates were calculated and compared across subspecialties and modalities. RESULTS. There were 194 callbacks among 147,068 MRI and 195,578 CT examinations. The callback rate for MRI was approximately nine times that of CT (MRI, 0.114% [n = 168]; CT, 0.013% [n = 26]). The callback rate was highest for musculoskeletal radiology (CT, 0.090% [7/7802]; MRI, 0.265% [73/27501]; p < 0.0001). Of 65 subspecialty radiologists, nine initiated 52% (101/194) of all callback examinations, and 20 initiated 80% (155/194). One musculoskeletal radiologist was responsible for 11.8% (23/194) of all callbacks. The most common reasons for callbacks were protocol error (28% [55/194]), inadequate anatomic coverage (21% [40/194]), incomplete examination (13% [25/194]), and perceived suboptimal image quality (11% [22/194]). The three most common causes of callbacks (62% [120/194] of all callbacks) were largely preventable. CONCLUSION. Outpatient callback examinations are uncommon, occur more often for MRI than CT, and are often preventable. Callback proclivities likely vary between attending radiologists. Targeted improvement efforts may mitigate callbacks.

Imaging of Peripheral Nerves of the Upper Extremity.

Peripheral neuropathy (often defined as weakness of sensory loss in one limb) of the upper extremity is a common clinical musculoskeletal scenario. The most common include carpal tunnel syndrome, cubital tunnel syndrome, and cervical radiculopathy. A combination of clinical examination, electrodiagnostic testing, and imaging studies, chiefly MR imaging and ultrasonography, is often needed to identify a specific diagnosis for an individual patient. In many cases, ultrasonography is preferred because of ease of access, the possibility of quick contralateral extremity imaging for comparison, and lower cost profile. MR imaging is preferred for deeper nerve structures and large-field-of-view evaluation.