Posterior capsule edema in adhesive capsulitis: comparison with established non-contrast MRI findings and multivariable analysis.

OBJECTIVES: To evaluate posterior glenohumeral capsule edema compared to other MRI findings in adhesive capsulitis (AC). METHODS: This study was approved by the local Institutional Review Board and it is HIPAA compliant. A retrospective search identified subjects who received fluoroscopically guided intra-articular corticosteroid injections for AC and had an MRI within 6 months prior to injection. The study group was compared with an age-, sex-, and side-matched control group who underwent the same procedures but did not have AC. MRIs were evaluated for edema of posterior capsule, anterior capsule, axillary pouch, coracohumeral ligament (CHL) and rotator interval (RI), thickness of axillary pouch and CHL, thickness of anterior capsule, RI and subcoracoid fat replacement, and teres minor atrophy and edema. Multivariable analysis was performed. RESULTS: A total of 57 subjects with AC and 57 matched controls were studied: mean age 52 ± 7 (range 31-71) years, 37 female and 20 male, 22 right and 35 left. Posterior capsule edema was more common in the AC group vs. control group (66.7 vs 17.5%, p < 0.001). Multivariable analysis showed posterior capsule edema, CHL edema, and axillary pouch (glenoid) thickness (optimum cutoff = 4 mm) were significant independent predictors of AC. Simplified analysis using these three variables had an area under the curve of 0.860 (95%CI: 0.792-0.928). With all three variables present, the sensitivity and specificity for AC were 32% and 98%, respectively. CONCLUSIONS: Posterior joint capsule edema may be helpful to confirm AC. Posterior capsule edema, CHL edema, and axillary pouch (glenoid) thickness produce a strong model for distinguishing AC from controls. CLINICAL RELEVANCE STATEMENT: Edema involving the posterior shoulder joint capsule is an imaging marker of capsulitis and is useful in differentiating patients with adhesive capsulitis from those without in conjunction with other proven MRI findings. KEY POINTS: • Posterior capsule edema has a sensitivity of 66.7% and a specificity of 82.5% for the detection of adhesive capsulitis. • Posterior capsule edema, coracohumeral ligament (CHL) edema, and axillary pouch (glenoid) thickness were significant independent predictors of adhesive capsulitis, and combining these variables together produces a very strong model for distinguishing cases from controls (AUC = 0.860). • Optimal cutoff values for CHL, axillary pouch (humeral), axillary pouch (glenoid), and axillary pouch (total) thickness were 2.5, 2.6, 4, and 6.3 mm, respectively.

Biomarkers of Body Composition.

The importance and impact of imaging biomarkers has been increasing over the past few decades. We review the relevant clinical and imaging terminology needed to understand the clinical and research applications of body composition. Imaging biomarkers of bone, muscle, and fat tissues obtained with dual-energy X-ray absorptiometry, computed tomography, magnetic resonance imaging, and ultrasonography are described.

Intraosseous pressure measurement during iliac bone marrow biopsy: its feasibility and difference of IOP in diseased marrow and non-diseased marrow.

OBJECTIVE: The purposes of this study were (1) to establish the feasibility and safety of an imaging-guided technique for intraosseous pressure (IOP) measurement in a large cohort of patients, and (2) to compare IOP values between normal and diseased bone marrow. METHODS: Adult patients undergoing CT-guided marrow biopsy were prospectively and consecutively enrolled from November 2020 to February 2022. IOP measurements were obtained connecting the biopsy needle to a monitoring device using a standard arterial line setup. Clinical data including sex, age and pathology results were obtained. Student t test and Pearson correlation were used for continuous variables comparisons. Univariable analyses were performed using Fisher's exact test. A P value of .05 was considered statistically significant. RESULTS: A total of 139 participants were initially enrolled, and four were excluded during technique optimization. There were no complications related to the measurement technique. Ninety participants (90/135, 67%) had histology confirming marrow pathology. The participants in the diseased marrow group were older than those in the normal marrow group (63 ± 14 vs. 55 ± 14 years; P < .01). There was no difference in mean IOP between both groups (66 ± 23 vs. 64 ± 28 mmHg; P = .69). There was no correlation between mean arterial blood pressure and mean IOP (P = .08). CONCLUSION: There was no difference in IOP measurements between patients with normal and diseased marrow undergoing CT-guided biopsy. IOP does not appear to be influenced by systemic blood pressure. No complication occurred during the procedures.

Current state of musculoskeletal fellowship program directors and future directions.

OBJECTIVE: To better understand the current state of musculoskeletal fellowship program directors and identify opportunities for formal training that could increase job satisfaction, provide a broader knowledge base for mentoring/advising trainees and increase diversity in musculoskeletal radiology. MATERIALS AND METHODS: Eighty-one fellowship program directors who signed the Fellowship Match Memorandum of Understanding with the Society of Skeletal Radiology were sent a survey with questions about demographics, career, background, and training both for musculoskeletal radiology and for the fellowship director role. RESULTS: A 57/81 (70%) of program directors responded, representing 27 different states with a range of 1-9 fellowship positions. Nearly half are in their forties (48%) with most identifying as White (67%) followed by Asian (30%). The majority are male (72%) with over half (60%) remaining at the institution where they completed prior training. Over half plan to change roles within 5 years and do not feel adequately compensated. Top qualities/skills identified as important for the role include effective communication, being approachable, and clinical excellence. Other than clinical excellence, most do not report formal training in skills identified as important for the role. CONCLUSIONS: Given the high amount of interaction with trainees, program directors play a key role in the future of our subspecialty. The low diversity among this group, the lack of formal training, and the fact that most do not feel adequately compensated could limit mentorship and recruitment. Program directors identified effective communication, organizational/planning skills, and conflict resolution as the top skills they would benefit from formal training.

Anterior and posterior hip osteoarthritis: prevalence and potential value of CT compared to radiographs.

PURPOSE: To determine the added value of computed tomography (CT) to identify severe hip osteoarthritis (OA). MATERIALS AND METHODS: A retrospective query of all cases of hip or knee arthroplasty planning CTs between January 2018 and March 2022 was performed. Age, sex, and symptoms were collected from the medical record. CTs were evaluated for the degree of osteoarthritis and classified using an adapted Kellgren-Lawrence (KL) grading system in the anterior, posterior, superior, and superomedial hip. Frontal hip or pelvis radiographs within 1 year of the CT were also graded. RESULTS: There were 265 eligible hips in 178 subjects, age 66 ± 11 (range 31-93) years, with 85/178 (48%) males and 93/178 (52%) females, and 127/265 (48%) right and 138/265 (52%) left hips. The posterior hip joint was the most common location for grade 2/3 OA (20%), followed by superior hip joint (14%). Anterior or posterior grade 2/3 OA occurred concurrently with superior or superomedial grade 2/3 OA in 32/68 (47%) of hips. Grade 2/3 OA was detected on CT more commonly than on XR both in the superior (14 vs 8.6%, P = 0.0016) and superomedial (8.7 vs 4.8%, P = 0.016) hip joint. Of the 71 symptomatic hips, 22 (31%) hips demonstrated either anterior and/or posterior grade 2/3 OA on CT, and 9 (9/22, 41%) of these hips had superior or superomedial grade 0/1 OA. CONCLUSION: CT may be warranted when the patient has pain suggestive of osteoarthritis not detected on radiographs.

Decreased rotator cuff muscle cross-sectional areas in subjects with adhesive capsulitis: a study comparing male and female subjects.

OBJECTIVE: To compare rotator cuff (RC) muscle cross-sectional areas (CSA) in subjects with adhesive capsulitis (AC) to age- and sex-matched controls. MATERIALS AND METHODS: We retrospectively analyzed 97 shoulder MRIs or MR arthrography studies, of which 42 were clinically diagnosed with AC (27 female, 15 male) and 55 were age- and sex-matched controls (38 female, 17 male). All AC subjects underwent imaging ≥ 6 months after symptom onset. All imaging was examined to exclude RC full-thickness tears and prior surgery. A standardized T1 sagittal MR image was segmented in each subject to obtain the CSA of subscapularis (SSC), supraspinatus (SSP), and infraspinatus (ISP) muscles. Differences in CSAs between AC and control subjects were analyzed by sex (females and males separately) and all subjects combined. RESULTS: AC females had significantly decreased SSC (P = 0.002) and total (P = 0.006) CSAs compared to controls. Male AC subjects showed decreased SSC (P = 0.044), SSP (P = 0.001), and total (P = 0.005) CSAs. Across all subjects, male and female, the AC cohort had significantly decreased SSC (P = 0.019) and total (P = 0.029) CSAs compared to controls. CONCLUSION: Decreased RC muscle CSAs were present in AC subjects with ≥ 6 months of symptom duration, with decreased SSC and total CSAs in male and female subjects, and decreased SSP CSA in males.

Phosphaturic mesenchymal tumor: management and outcomes of ten patients treated at a single institution.

BACKGROUND: Phosphaturic mesenchymal tumor (PMT) is a rare tumor that causes tumor-induced osteomalacia. Patients present with non-specific symptoms secondary to renal phosphate wasting and decreased bone mineralization. We sought to assess: (1) What are the common presenting features, laboratory and imaging findings, histologic findings of phosphaturic mesenchymal tumors? (2) What are the available treatment strategies for phosphaturic mesenchymal tumors and their long-term outcomes in terms of local recurrence and symptom control after treatment? METHODS: We retrospectively identified patients with a histologic diagnosis of PMT located in the axial or appendicular skeleton, or surrounding soft tissues. A total of 10 patients were finally included in our study. RESULTS: Median tumor size was 1.9 cm (range, 1.1 to 6.1) and median time from symptom onset to diagnosis was 3 years (range, 0.5 to 15 years). All patients but one presented with hypophosphatemia (median 1.9 mg/dL, range 1.2 to 3.2). Pre-operative FGF-23 was elevated in all cases (median 423.5 RU/mL, range 235 to 8950). Six patients underwent surgical resection, three were treated percutaneously (radiofrequency ablation or cryoablation), and one refused treatment. Only one patient developed local recurrence and no patients developed metastatic disease. At last follow-up, nine patients showed no evidence of disease and one was alive with disease. CONCLUSION: Phosphaturic mesenchymal tumor is a rare tumor presenting with non-specific symptoms. Surgery is the standard treatment when negative margins can be achieved without significant morbidity. In patients with small tumors in surgically-inaccessible areas, radiofrequency ablation or cryoablation can be performed successfully.

CT-guided lumbar facet cyst rupture and corticosteroid injection: technique, approach, and procedural and clinical success rates.

PURPOSE: To evaluate success rates of computed tomography (CT)-guided lumbar facet synovial cyst (LFC) rupture. MATERIALS AND METHODS: We retrospectively reviewed all LFC ruptures performed by a single musculoskeletal radiologist with > 10 years of experience, using posterior facet approach and/or direct puncture by ipsilateral/contralateral interlaminar, or transforaminal approach. All patients also received a corticosteroid injection. Rupture rates were calculated, and clinical success rate was determined through medical record review. Pre-procedure magnetic resonance imaging (MRI) images and CT procedure images were also reviewed for LFC and facet joint imaging features that may predict rupture. RESULTS: There were 37 patients, 17 (46%) female and 20 (54%) male, ages 62 ± 12 (range 39-87) years. Thirty-four (92%) of LFC were successfully ruptured, 17 (50%) by facet approach and 17 (50%) by direct cyst puncture. At least one direct puncture approach was possible in 35 (95%) patients. No MRI or CT LFC or facet joint features predicted cyst rupture. Thirty-one (91%) of patients reported immediate pain relief, and 19 (53%) did not have further intervention for LFC-related pain. Sixteen (84%) of these patients remained pain-free for an average follow-up time period of 28 months. Fourteen (39%) of patients required surgical intervention. There were no complications. CONCLUSION: Our systematic approach to CT-guided LFC rupture is safe and has high technical and clinical success rates similar to prior studies. Since there are no definitive imaging features that determine rupture success, this procedure can almost always be attempted as a first-line treatment for LFC.

Bone Density Screening Rates Among Medicare Beneficiaries: An Analysis with a focus on Asian Americans.

PURPOSE: To report osteoporosis screening utilization rates among Asian American (AsA) populations in the USA. METHODS: We retrospectively assessed the use of dual-energy X-ray absorptiometry (DXA) screening using the Medicare 5% Research Identifiable Files. Using Current Procedural Terminology (CPT) codes indicative of a DXA scan, we identified patients recommended for DXA screening according to the ACR-SPR-SSR Practice Parameters (females ≥ 65 years, males ≥ 70 years). Sociodemographic factors and their association with screening were evaluated using chi-square tests. RESULTS: There were 80,439 eligible AsA beneficiaries, and 12,102 (15.1%) received osteoporosis screening. DXA rate for women was approximately four times greater than the rate for men (19.8% vs. 5.0%; p < 0.001). AsA beneficiaries in zip codes with higher mean household income (MHI) were more likely to have DXA than those in lower MHI areas (17.6% vs. 14.3%, p < 0.001). AsA beneficiaries aged < 80 were more likely to receive DXA (15.5%) than those aged ≥ 80 (14.1%, p < 0.001). There were 2,979,801 eligible non-AsA beneficiaries, and 496,957 (16.7%) received osteoporosis screening during the study period. Non-Hispanic white beneficiaries had the highest overall screening rate (17.5%), followed by North American Native (13.0%), Black (11.8%), and Hispanic (11.1%) beneficiaries. Comparing AsA to non-AsA populations, there were significantly lower DXA rates among AsA beneficiaries when controlling for years of Medicare eligibility, patient age, sex, location, and mean income (p < 0.001). CONCLUSION: We found lower than expected DXA screening rates for AsA patients. A better understanding of the barriers and facilitators to AsA osteoporosis screening is needed to improve patient care.

Can gas and infection coexist in the intervertebral disc? A retrospective analysis of percutaneously biopsied suspected discitis-osteomyelitis cases.

OBJECTIVES: To retrospectively evaluate the correlation between intradiscal gas and infection in patients percutaneously biopsied for suspected discitis-osteomyelitis. MATERIALS AND METHODS: We retrospectively reviewed all CT-guided discitis-osteomyelitis biopsies performed between 2002 and 2022. Two independent trained musculoskeletal radiologists evaluated for presence of gas on CT and/or MRI within 1 week of the biopsy. Disagreements were resolved by a third musculoskeletal radiologist. CT was considered the gold standard for the detection of intradiscal gas. Pathology, microbiology, and imaging and clinical follow-up were used as the gold standard for presence of infection. Interrater agreement on CT and MRI, sensitivity, and positive predictive value were calculated, using the presence of gas as an indicator (test positive) for "no infection." RESULTS: There were 284 biopsies in 275 subjects (mean age 58 ± 1.0 (range 4-99) years; 101 (37%) females and 174 (63%) males). Of the biopsies, 12 (4%) were cervical, 80 (28%) were thoracic, 192 (68%) were lumbar, and 200 (70%) were considered true discitis-osteomyelitis based on pathology, imaging, and clinical follow-up. Interrater agreement was excellent for CT (kappa = 0.83) and poor for MRI (kappa = - 0.021). The presence of gas had a 94% specificity and 76% negative predictive value for the absence of infection. CONCLUSION: CT is the preferred method for detecting intradiscal gas. The presence of gas means that discitis-osteomyelitis is unlikely. If intradiscal gas is present in the setting of discitis-osteomyelitis, the gas bubbles tend to be smaller and fewer in number.

Relationship of Imaging-guided Corticosteroid Injections to COVID-19 Incidence in the Pandemic Recovery Period.

Background Corticosteroids injected for the treatment of musculoskeletal pain are systemically absorbed and can affect the immune response to viral infections. Purpose To determine the incidence of symptomatic COVID-19 disease in individuals receiving image-guided corticosteroid injections for musculoskeletal pain compared with the general population during the pandemic recovery period. Materials and Methods In this prospective cohort multicenter study, adults with a history of musculoskeletal pain who underwent imaging-guided intra-articular and spine corticosteroid injections from April 2020 to February 2021 were consecutively enrolled. Participants were followed for a minimum of 28 days through their electronic medical record (EMR) or by direct phone communication to screen for COVID-19 test results or symptoms. Clinical data, including body mass index (BMI), were also obtained from the EMR. The incidence of COVID-19 in the state was obtained using the Massachusetts COVID-19 Response Reporting website. The Student t test was used for continuous variable comparisons. Univariable analyses were performed using the Fisher exact test. Results A total of 2714 corticosteroid injections were performed in 2190 adult participants (mean age, 59 years ± 15 [SD]; 1031 women). Follow-up was available for 1960 participants (89%) who received 2484 injections. Follow-up occurred a mean of 97 days ± 33 (range, 28-141 days) after the injection. Of the 1960 participants, 10 had COVID-19 within 28 days from the injection (0.5% [95% CI: 0.24, 0.94]) and 43 had COVID-19 up to 4 months after the injection (2.2% [95% CI: 1.6, 2.9]). These incidence rates were lower than that of the population of Massachusetts during the same period (519 195 of 6 892 503 [7.5%], P < .001 for both 28 days and 4 months). Participants diagnosed with COVID-19 (n = 10) within 28 days from the injection had a higher BMI than the entire cohort (n = 1960) (mean, 32 kg/m2 ± 10 vs 28 kg/m2 ± 6; P = .04). Conclusion Adults who received image-guided corticosteroid injections for pain management during the pandemic recovery period had a lower incidence of symptomatic COVID-19 compared with the general population. © RSNA, 2022 Online supplemental material is available for this article.

Image-Guided Biopsy in Acute Diskitis-Osteomyelitis: A Systematic Review and Meta-Analysis.

BACKGROUND. The reported sensitivity and yield of image-guided biopsies for diskitis-osteomyelitis vary widely. OBJECTIVE. The purpose of this study was to perform a systematic review of the literature and meta-analysis of pooled sensitivity data to elucidate strategies for optimal image-guided biopsies among patients suspected to have diskitis-osteomyelitis. EVIDENCE ACQUISITION. A comprehensive literature search was performed for studies of patient populations with proven or suspected diskitis-osteomyelitis that included percutaneous image-guided biopsy as part of the workup algorithm. Type of pathogens, imaging modality used for biopsy guidance, tissue targeted, antibiotic administration at the time of biopsy, true microbiology positives, true microbiology negatives, false microbiology positives, false microbiology negatives, disease (i.e., diskitis-osteomyelitis) positives as determined by reference standard, true infection positives (i.e., positive microbiology or pathology results), and total number of biopsies performed were extracted from the studies. Microbiology sensitivity, microbiology biopsy yield, and infection sensitivity were calculated from the pooled data. These terms and the data required to calculate them were also defined in detail. EVIDENCE SYNTHESIS. Thirty-six articles satisfied inclusion criteria and were used for analysis. The pooled microbiology sensitivity, infection sensitivity, and microbiology biopsy yields were 46.6%, 70.0%, and 26.7%, respectively. Mycobacterium tuberculosis-only microbiology sensitivity was significantly higher than both pyogenic bacteria and mixed-organism microbiology sensitivity (p < .001). Staphylococcus aureus was the most common causative organism (28.6%). Pooled microbiology sensitivity was not significantly different for CT guidance and fluoroscopy guidance (p = .16). There was a statistically significant difference between pooled microbiology sensitivity of bone/end plate (45.5%) and disk/paravertebral soft-tissue (64.8%) image-guided biopsies (p < .001). There was no statistically significant difference in pooled microbiology sensitivities for patients who received antibiotics before the procedure (46.2%) and those who did not (44.6%) (p = .70). CONCLUSION. Image guidance by CT or fluoroscopy does not affect microbiology yield, disk and paravertebral soft-tissue biopsies should be considered over bone and end plate biopsies, and preprocedural antibiotic administration does not appear to impact biopsy results. CLINICAL IMPACT. Understanding and correctly applying reported statistics contribute to appropriate interpretation of the abundant literature on this topic and optimization of care for patients with diskitis-osteomyelitis.

Original research: utilization of a convolutional neural network for automated detection of lytic spinal lesions on body CTs.

OBJECTIVE: To develop, train, and test a convolutional neural network (CNN) for detection of spinal lytic lesions in chest, abdomen, and pelvis CT scans. MATERIALS AND METHODS: Cases of malignant spinal lytic lesions in CT scans were identified. Images were manually segmented for the following classes: (i) lesion, (ii) normal bone, (iii) background. If more than one lesion was on a single slice, all lesions were segmented. Images were stored as 128×128 pixel grayscale, with 10% segregated for testing. The training pipeline of the dataset included histogram equalization and data augmentation. A model was trained on Keras/Tensorflow using an 80/20 training/validation split, based on U-Net architecture. Additional testing of the model was performed on 1106 images of healthy controls. Global sensitivity measured detection of any lesion on a single image. Local sensitivity and positive predictive value (PPV) measured detection of all lesions on an image. Global specificity measured false positive rate in non-pathologic bone. RESULTS: Six hundred images were obtained for model creation. The training set consisted of 540 images, which was augmented to 20,000. The test set consisted of 60 images. Model training was performed in triplicate. Mean Dice scores were 0.61 for lytic lesion, 0.95 for normal bone, and 0.99 for background. Mean global sensitivity was 90.6%, local sensitivity was 74.0%, local PPV was 78.3%, and global specificity was 63.3%. At least one false positive lesion was noted in 28.8-44.9% of control images. CONCLUSION: A task-trained CNN showed good sensitivity in detecting spinal lytic lesions in axial CT images.

Outcomes of imaging-guided corticosteroid injections in hip and knee osteoarthritis patients: a systematic review.

PURPOSE: The purpose of this systematic review is to evaluate the current literature on the use of image-guided corticosteroid injections in the treatment of patients with knee and hip OA. EVIDENCE ACQUISITION: We conducted a comprehensive literature search through June 30, 2022. Publication type, study design, imaging guidance modality, osteoarthritis severity, number of injections, steroid type and dose, anesthetic type and dose, the total number of patients, follow-up intervals, and measured outcomes were extracted from the included studies. EVIDENCE SYNTHESIS: There were 23 included studies (10 hips, 12 knees, 1 both hip and knee). Hip injections were found to be effective in treating short- and long-term pain and more effective than hyaluronic acid, Mepivacaine, NSAIDs, and normal saline in terms of improvement in pain and/or function. There was less impact on QoL. Knee injections were found either to have little or no impact or were similar or inferior to comparison injections (intra-articular hyaluronic acid, PRP, NSAIDs, normal saline, adductor canal blocks). Study data could not be aggregated because the corticosteroid types and doses, methods of outcome assessment, and follow-up time points varied widely. CONCLUSION: Our systematic review found generally positive outcomes for the hip, but overall negative outcomes for the knee, although hip injections may carry a risk of serious adverse outcomes. A larger trial with uniform methodology is warranted. Specific studies on the adverse effects of corticosteroid injections are also warranted.

A novel core biopsy needle with shorter dead space for percutaneous image-guided musculoskeletal biopsies - how does it compare with an established core biopsy needle?

PURPOSE: To compare diagnostic yield and utility of a novel core biopsy needle (NCBN) with shortened tip dead space for percutaneous musculoskeletal biopsies with an established core biopsy needle (ECBN). METHODS: This study was IRB approved and HIPAA compliant. All percutaneous biopsies using an NCBN performed between July 2020 and August 2021 were retrospectively reviewed. Data on patient demographics, biopsy technique, biopsy needle, and histopathology were collated. RESULTS: Thirty-six patients were included in this study, 16 (44%) undergoing biopsy with both an NCBN and an ECBN, and 20 (56%) with an NCBN only. All 36 NCBN biopsies were 16 gauge. Fifteen (94%) of the ECBN biopsies were 14 gauge, and 1 (6%) was 16 gauge. Thirty-four (94%) of the NCBN and 15 (94%) of the ECBN biopsies were diagnostic. No adverse events were identified. CONCLUSION: Both the NCBN and ECBN have high diagnostic rates. No adverse events were identified. NCBN could be considered for biopsy of lesions limited by anatomic location or near adjacent critical structures.

Postoperative Imaging of the Rotator Cuff: A Systematic Review and Meta-Analysis.

BACKGROUND. It is unclear which, MRI or ultrasound (US), is the most useful imaging tool to diagnose rotator cuff retears. OBJECTIVE. The objective of this study was to evaluate MRI and US in terms of diagnosing retear of a repaired rotator cuff tendon using a systematic review and meta-analysis. EVIDENCE ACQUISITION. A comprehensive literature search was performed on the main concepts of MRI (including noncontrast MRI and MR arthrography), US, and rotator cuff repairs. Inclusion criteria consisted of original research studies that assessed the diagnostic accuracy of MRI and US (index tests) for the diagnosis of rotator cuff tendon retear after prior rotator cuff repair using surgical findings as the reference standard. QUADAS-2 was used to assess methodologic quality. Meta-analyses were performed to compare MRI and US studies in the diagnosis of all retears and of full-thickness retears. Study variation was analyzed using the Cochran Q test and I2 statistic. EVIDENCE SYNTHESIS. Eight studies (MRI, n = 6; US, n = 2) satisfied inclusion and exclusion criteria, consisting of 304 total patients (MRI, n = 221; US, n = 83) and 309 shoulders (MRI, n = 226; US, n = 83). Years of publication ranged from 1993 to 2006 for the MRI studies and from 2003 to 2018 for the US studies. Two studies had high risk of bias in terms of applicability to clinical practice because of patient selection. Five studies had potential risk of bias in two categories, whereas two had potential risk of bias in three categories. For all retears, mean sensitivity and specificity for MRI were 81.4% (95% CI, 73.3-87.5%) and 82.6% (95% CI, 76.3-87.5%) and 83.7% (95% CI, 67.4-92.7%) and 90.7% (95% CI, 73.6-97.1%) for US. For full-thickness retears, mean sensitivity and specificity for MRI were 85.9% (95% CI, 80.2-90.2%) and 89.1% (95% CI, 84.6-92.4%) and 89.7% (95% CI, 75.6-96.1%) and 91.0% (95% CI, 75.5-97.1%) for US. There was no significant difference in terms of sensitivity or specificity for either comparison (p = .28-.76). CONCLUSION. Our analyses revealed no significant difference between US and MRI for the diagnosis of rotator cuff tendon tears after prior cuff repair. CLINICAL IMPACT. Either MRI or US can be considered a first-line imaging option to assess suspected rotator cuff retear after prior repair.

Automated detection and segmentation of sclerotic spinal lesions on body CTs using a deep convolutional neural network.

PURPOSE: To develop a deep convolutional neural network capable of detecting spinal sclerotic metastases on body CTs. MATERIALS AND METHODS: Our study was IRB-approved and HIPAA-compliant. Cases of confirmed sclerotic bone metastases in chest, abdomen, and pelvis CTs were identified. Images were manually segmented for 3 classes: background, normal bone, and sclerotic lesion(s). If multiple lesions were present on a slice, all lesions were segmented. A total of 600 images were obtained, with a 90/10 training/testing split. Images were stored as 128 × 128 pixel grayscale and the training dataset underwent a processing pipeline of histogram equalization and data augmentation. We trained our model from scratch on Keras/TensorFlow using an 80/20 training/validation split and a U-Net architecture (64 batch size, 100 epochs, dropout 0.25, initial learning rate 0.0001, sigmoid activation). We also tested our model's true negative and false positive rate with 1104 non-pathologic images. Global sensitivity measured model detection of any lesion on a single image, local sensitivity and positive predictive value (PPV) measured model detection of each lesion on a given image, and local specificity measured the false positive rate in non-pathologic bone. RESULTS: Dice scores were 0.83 for lesion, 0.96 for non-pathologic bone, and 0.99 for background. Global sensitivity was 95% (57/60), local sensitivity was 92% (89/97), local PPV was 97% (89/92), and local specificity was 87% (958/1104). CONCLUSION: A deep convolutional neural network has the potential to assist in detecting sclerotic spinal metastases.

Artificial intelligence applied to musculoskeletal oncology: a systematic review.

Developments in artificial intelligence have the potential to improve the care of patients with musculoskeletal tumors. We performed a systematic review of the published scientific literature to identify the current state of the art of artificial intelligence applied to musculoskeletal oncology, including both primary and metastatic tumors, and across the radiology, nuclear medicine, pathology, clinical research, and molecular biology literature. Through this search, we identified 252 primary research articles, of which 58 used deep learning and 194 used other machine learning techniques. Articles involving deep learning have mostly involved bone scintigraphy, histopathology, and radiologic imaging. Articles involving other machine learning techniques have mostly involved transcriptomic analyses, radiomics, and clinical outcome prediction models using medical records. These articles predominantly present proof-of-concept work, other than the automated bone scan index for bone metastasis quantification, which has translated to clinical workflows in some regions. We systematically review and discuss this literature, highlight opportunities for multidisciplinary collaboration, and identify potentially clinically useful topics with a relative paucity of research attention. Musculoskeletal oncology is an inherently multidisciplinary field, and future research will need to integrate and synthesize noisy siloed data from across clinical, imaging, and molecular datasets. Building the data infrastructure for collaboration will help to accelerate progress towards making artificial intelligence truly useful in musculoskeletal oncology.

Percutaneous CT-guided corticosteroid injection for the treatment of osseous Langerhans cell histocytosis: a three institution retrospective analysis.

PURPOSE: The aim of this study is to evaluate the safety and effectiveness of CT-guided corticosteroid injection for the treatment of osseous Langerhans cell histiocytosis (LCH) in a multi-institutional study. MATERIALS AND METHODS: This IRB-approved study included patients from three institutions. We retrospectively reviewed clinical, procedural, and imaging data for corticosteroid injections performed to treat osseous LCH. Location of the lesion, lesion maximum dimension and volume, corticosteroid type and dose, and time interval between injection and change in lesion size/volume and symptoms were recorded. Generalized estimating equations (accounting for multiple lesions per subject) were used to evaluate the association between predictors (dose, maximum lesion dimension, and lesion volume) and outcomes (time to partial and complete radiographic resolution, and time to pain control). This analysis was adjusted by anatomic site. RESULTS: Forty corticosteroid injections were performed in 36 patients (20 (56%) females, and 16 (44%) males, ages 12 ± 11 (2-57) years). Mean lesion maximum dimension was 3.2 ± 1.7 cm, and volume was 10 ± 17 cm3. Imaging and clinical follow-up were available for 22/40 (55%) and 34/40 (85%) of injections, respectively. All lesions responded to corticosteroid injection. Times to partial and complete imaging resolution were 13 ± 9 and 32 ± 13 weeks, respectively, and time to pain resolution was 22 ± 14 weeks. There were no complications. CONCLUSION: CT-guided corticosteroid injection is a safe and effective treatment for LCH. Pain resolution was achieved in all patients and imaging did not show progressive disease in any of the patients.

Society of Skeletal Radiology- white paper. Guidelines for the diagnostic management of incidental solitary bone lesions on CT and MRI in adults: bone reporting and data system (Bone-RADS).

The purpose of this article is to present algorithms for the diagnostic management of solitary bone lesions incidentally encountered on computed tomography (CT) and magnetic resonance (MRI) in adults. Based on review of the current literature and expert opinion, the Practice Guidelines and Technical Standards Committee of the Society of Skeletal Radiology (SSR) proposes a bone reporting and data system (Bone-RADS) for incidentally encountered solitary bone lesions on CT and MRI with four possible diagnostic management recommendations (Bone-RADS1, leave alone; Bone-RADS2, perform different imaging modality; Bone-RADS3, perform follow-up imaging; Bone-RADS4, biopsy and/or oncologic referral). Two algorithms for CT based on lesion density (lucent or sclerotic/mixed) and two for MRI allow the user to arrive at a specific Bone-RADS management recommendation. Representative cases are provided to illustrate the usability of the algorithms.