Demonstration of transverse ligament on 3D SPACE MRI in whiplash-associated disorder and nontraumatic conditions.

PURPOSE: This study aims to delineate the three-dimensional (3D) SPACE MRI findings of the transverse ligament (TL) in whiplash-associated disorder (WAD) patients, and to compare them with those from a nontraumatic group. METHODS: A retrospective analysis was performed on cervical spine MRI scans obtained from 46 patients with WAD and 62 nontraumatic individuals. Clinical features, including the WAD grade and stage, were recorded. The TL's morphological grade and the symmetricity of the lateral atlantodental interval was assessed using axial 3D T2-SPACE images. The morphological grading was evaluated using a four-point scale: 0 = homogeneously low signal intensity with normal thickness, 1 = high signal intensity with normal thickness, 2 = reduced thickness, 3 = full-thickness rupture or indistinguishable from surrounding structures. Additionally, the number of cervical levels exhibiting degeneration was documented. RESULTS: When comparing the WAD and nontraumatic groups, a significant difference was observed in the proportion of high-grade TL changes (grade 2 or 3) and the number of degenerated cervical levels. Logistic regression analysis revealed that high-grade TL changes and a lower number of degenerative levels independently predicted the presence of WAD. Within the WAD group, the subset of patients with high-grade TL changes demonstrated a significantly higher mean age than the low-grade group (grade 0 or 1). CONCLUSION: High-grade morphological changes in the TL can be detected in patients with WAD through the use of 3D SPACE sequences. Clinical relevance statement 3D SPACE MRI could serve as an instrumental tool in the assessment of TL among patients with WAD. Integrating MRI findings with patient history and symptomology could facilitate the identification of potential ligament damage, and may help treatment and follow-up planning.

Comparison between 2D TSE and 3D SPACE in the evaluation of craniocervical ligaments.

PURPOSE: To evaluate the MRI findings of the craniocervical junction ligaments and compare the 2D TSE sequence and 3D SPACE sequence on cervical spine MRI. METHODS: Eighty cervical spine MRIs were retrospectively analyzed, including 2D TSE and 3D SPACE sequences. The visibility and morphology of the transverse ligament (TL) and alar ligament (AL) were evaluated by two readers using a five-point grading scale for visibility (1 = not visible, 2 = barely visible, 3 = adequately visible, 4 = good visibility, 5 = excellent visibility) and a four-point grading scale for morphology (0 = homogeneous low SI with normal thickness, 1 = high SI with normal thickness, 2 = reduced thickness, 3 = full-thickness rupture or indistinguishable from surrounding structures). The grades of the two sequences were compared. Reader agreements were measured using the percentage of exact agreement. RESULT: The visibility grade of TL was significantly higher in 3D, indicating better visualization. The morphology grade of TL was significantly lower in the 3D, indicating more normal-appearing ligament. The exact agreements of visibility and morphology grade of TL tended to be higher in 3D. On the other hand, there was no significant difference in visibility grade of AL between the two sequences. The morphological grade of AL was significantly higher in 3D. The agreement of the morphological grade of AL tended to be lower in 3D. CONCLUSION: The utilization of 3D sequences significantly improves the visibility of TL and could potentially reduce false-positive diagnoses of ligament injury.

Hip Magnetic Resonance Arthrography Using Normal Saline Is Less Accurate Than Using a Gadolinium-Based Contrast Agent.

PURPOSE: To evaluate the diagnostic performance of hip magnetic resonance (MR) arthrography with a gadolinium-based contrast agent (GBCA) or normal saline (NS) for intra-articular pathologies. METHODS: This retrospective study was approved by the institutional review board of our hospital, and the requirement for informed consent was waived. The study included 37 consecutive patients (38 hips; 21 right hips; 24 males; mean age, 33 years) who underwent GBCA-hip MR arthrography from July 2011 to January 2020 and 30 consecutive patients (30 hips; 20 right hips; 21 males; mean age, 40 years) who underwent NS-hip MR arthrography from January 2018 to June 2020. All images were evaluated twice independently by two radiologists blinded to the arthroscopic findings for the presence of labral tears, cartilage abnormalities, or ligamentum teres tears. Intrareader and interreader reliabilities were determined by kappa values (k) using the chi-squared test, and diagnostic performance was evaluated based on the arthroscopic findings. A P value less than .05 was considered to indicate statistical significance. RESULTS: Intra-reader reliability in the detection of intra-articular pathologies ranged from moderate to almost perfect (k = 0.510-0.840) and inter-reader reliability ranged from moderate to substantial (k = 0.441-0.695) for GBCA- and NS-hip MR arthrography. The diagnostic accuracy of GBCA- and NS-hip MR arthrography was as follows: 81.6-92.1% and 66.7-73.3% for labral tears, respectively; 68.4-86.8% and 63.3-70.0% for cartilage abnormality, respectively; and 68.4-76.3% and 50.0-56.7% for ligamentum teres tears, respectively. CONCLUSION: NS-hip MR arthrography may be less accurate than GBCA-hip MR arthrography. LEVEL OF EVIDENCE: Level II of development of diagnostic criteria (consecutive patients with consistently applied reference standard and blinding).

Evaluation of the efficacy and safety of epidural steroid injection using a nonparticulate steroid, dexamethasone or betamethasone: a double-blind, randomized, crossover, clinical trial.

Background: The U.S. Food and Drug Administration has prohibited epidural steroid injection (ESI) with particulate steroids. Thus, this study aimed to compare the efficacy and safety of ESI with two nonparticulate steroids, dexamethasone and betamethasone. Methods: The eligible patients (n = 600) who received ESI (0 week) with dexamethasone (ESI-dexa) or betamethasone (ESI-beta) had follow-up visits at 2, 4, and 8 weeks with a phone interview at 12 weeks. The primary endpoint was the proportion of effective responders without pain or who were much improved at 2 weeks. The secondary endpoints were the proportion of crossover injections at 2 weeks; changes in the visual analog scale (VAS) and disability index scores at 2, 4, and 8 weeks; the number of additional ESIs in 12 weeks; the number of participants having spinal surgery, as well as the incidence of adverse events over the 12 weeks. Results: The proportion of effective responders at 2 weeks was not different between ESI-beta (72/216, 33.3%) and ESI-dexa (63/200, 31.5%; P = 0.670). Adverse events were more common with ESI-dexa (40/200, 20.0%) than with ESI-beta (24/216, 11.1%; P = 0.012). VAS scores decreased more with ESI-beta than with ESI-dexa at 2 weeks (difference, 0.35; P = 0.023) and 4 weeks (difference, 0.42; P = 0.011). The disability score improved significantly more with ESI-beta compared with ESI-dexa at 2 weeks (difference, 3.37; P = 0.009), 4 weeks (difference, 4.01; P = 0.002), and 8 weeks (difference, 3.54; P = 0.007). Conclusions: Betamethasone would be more appropriate for ESI.

Prevalence, Clinical Implication, and Cause of Spine Hip Discordance in Elderly Patients with Fragility Hip Fracture.

BACKGROUND: Spine-hip discordance (SHD) increases fracture risk. However, its prevalence and clinical implications have not been investigated in patients with hip fractures. This study determined the prevalence and association of SHD with mortality and investigated the cause of SHD in patients with hip fractures. METHODS: This study included patients admitted for fragility hip fractures between 2011 and 2020. All patients underwent dual energy X-ray absorptiometry and anteroposterior and lateral views of the lumbosacral spine during admission. Data on demographics, diagnosis, American Society of Anesthesiologists score, and mortality were collected. A T-score difference of more than 1.5 between L1-4 and the femur neck was considered discordant, and 3 groups (lumbar low [LL] discordance, no discordance [ND], and femur neck low [FL] discordance) were compared. In the discordance group, lumbar radiographs were reviewed to determine the cause of discordance. RESULTS: Among 1,220 eligible patients, 130 were excluded due to patient refusal or bilateral hip implantation; therefore, this study included 1,090 patients (271 male and 819 female). The prevalence of LL, ND, and FL was 4.4%, 66.4% and 29.2% in men and 3.9%, 76.1%, and 20.0% women. Mortality was not associated with discordance. The most common causes of discordance were physiological in the LL group and pathological in the FL group for both sexes. CONCLUSIONS: Patients with hip fractures showed lower rates of ND and higher rates of FL compared to the general population. True discordance should be carefully judged for pathological and artifact reasons. The clinical implications of SHD require further investigation.

Diagnosing ulnar neuropathy at the elbow on MRI: importance of the longitudinal extent of the hyperintense ulnar nerve.

OBJECTIVE: To evaluate the usefulness of the longitudinal extent (LE) of high ulnar nerve signal intensity (SI) for the diagnosis of ulnar neuropathy at the elbow (UNE). MATERIALS AND METHODS: This retrospective study included 68 patients who underwent elbow MRI. Twenty-seven and 41 patients were enrolled in the UNE and control groups, respectively. Qualitative and quantitative analyses of the SI and size of the ulnar nerve at the cubital tunnel, proximal, and distal to the cubital tunnel were performed. Cross-sectional area (CSA) and nerve-to-muscle contrast ratio (NMCR) were measured at each level. The LE of the hyperintense ulnar nerve was evaluated using axial and coronal images. The presence of space-occupying lesions (SOLs), subluxation, and muscle denervation were recorded. Univariate and multivariate analyses were performed to identify independent predictive factors. RESULTS: Ulnar nerve hyperintensity at and distal to the cubital tunnel, presence of compression, SOL, muscle denervation, LE of hyperintense ulnar nerve, NMCR, and CSA at and distal to the cubital tunnel significantly differed between the two groups. Multivariate logistic regression analysis showed that the LE of the hyperintense ulnar nerve and CSA at the cubital tunnel were independent predictive factors for UNE (p < 0.05). CONCLUSION: LE of the hyperintense ulnar nerve could be a useful predictive factor for UNE.

Method for Diagnosing the Bone Marrow Edema of Sacroiliac Joint in Patients with Axial Spondyloarthritis Using Magnetic Resonance Image Analysis Based on Deep Learning.

Axial spondyloarthritis (axSpA) is a chronic inflammatory disease of the sacroiliac joints. In this study, we develop a method for detecting bone marrow edema by magnetic resonance (MR) imaging of the sacroiliac joints and a deep-learning network. A total of 815 MR images of the sacroiliac joints were obtained from 60 patients diagnosed with axSpA and 19 healthy subjects. Gadolinium-enhanced fat-suppressed T1-weighted oblique coronal images were used for deep learning. Active sacroiliitis was defined as bone marrow edema, and the following processes were performed: setting the region of interest (ROI) and normalizing it to a size suitable for input to a deep-learning network, determining bone marrow edema using a convolutional-neural-network-based deep-learning network for individual MR images, and determining sacroiliac arthritis in subject examinations based on the classification results of individual MR images. About 70% of the patients and normal subjects were randomly selected for the training dataset, and the remaining 30% formed the test dataset. This process was repeated five times to calculate the average classification rate of the five-fold sets. The gradient-weighted class activation mapping method was used to validate the classification results. In the performance analysis of the ResNet18-based classification network for individual MR images, use of the ROI showed excellent detection performance of bone marrow edema with 93.55 ± 2.19% accuracy, 92.87 ± 1.27% recall, and 94.69 ± 3.03% precision. The overall performance was additionally improved using a median filter to reflect the context information. Finally, active sacroiliitis was diagnosed in individual subjects with 96.06 ± 2.83% accuracy, 100% recall, and 94.84 ± 3.73% precision. This is a pilot study to diagnose bone marrow edema by deep learning based on MR images, and the results suggest that MR analysis using deep learning can be a useful complementary means for clinicians to diagnose bone marrow edema.

Analysis of Fracture Characteristic and Medial Collateral Ligament Injury Relationships in Terrible Triad Elbow Injuries.

PURPOSE: The objectives of this study were to identify the relationship between fracture characteristics and medial collateral ligament (MCL) injuries in terrible triad injuries of the elbow. METHODS: Between 2010 and 2018, 60 patients who underwent surgery for terrible triad elbow injuries were retrospectively reviewed. Using magnetic resonance imaging (MRI) assessments, patients were stratified into those who had intact or low-grade partial MCL tears (low-grade MRI-MCL group) and those who had high-grade partial or full-thickness MCL tears (high-grade MRI-MCL group). We also analyzed patients according to whether they underwent MCL repair surgery. Fractures of the radial head were assessed according to Mason's classification system and measurements of fracture fragment arc on axial cuts. Fractures of the coronoid processes were assessed according to the system of Regan and Morrey and measurements of coronoid process volumes. RESULTS: Patients in the high-grade MRI-MCL group (28 patients) had a more comminuted and higher fragment arc of radial head fractures than those in the low-grade MRI-MCL group (32 patients) (143º ± 45º vs 119º ± 31º). However, the volume of coronoid fracture fragments was smaller in the high-grade MRI-MCL than in the low-grade MRI-MCL group (359 ± 325 mm3 vs 722 ± 448 mm3). The MCL repair group (22 patients) also had a more comminuted and higher fragment arc in radial head fractures (153º ± 44º vs 117º ± 31º) and a smaller coronoid process fracture volume (236 ± 224 mm3 vs 735 ± 419 mm3) than the non-MCL repair group (38 patients). CONCLUSIONS: Our results demonstrated that high-grade MCL injuries are associated with comminuted and larger-sized radial head fractures, as well as smaller-sized coronoid process fractures in terrible triad injuries. In making a decision regarding surgical treatment, these fracture characteristics could help to predict the severity for MCL injury in terrible triad injuries. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic IV.

MRI features of symptomatic amputation neuromas.

OBJECTIVES: To demonstrate the magnetic resonance imaging (MRI) features of amputation neuromas in lower extremity amputees and investigate independent predictive MRI features for symptomatic neuromas. METHODS: This retrospective study included 45 amputation neuromas in 44 lower extremity amputees. Two radiologists assessed the imaging features, including shape, size, type (end-bulb or spindle), signal intensity (SI), heterogeneity, margins, enlarged fascicles, dark outer rim, tail sign, target sign, enhancement, perilesional fibrosis, and muscle denervation. The neuromas were categorized into symptomatic (n = 24) or asymptomatic (n = 21). Symptomatic neuromas were determined based on neuropathic pain characteristics, the presence of Tinel's sign or tenderness, and response to local anesthetic injection. Univariate and multivariate analyses were performed to identify independent predictive MRI features. RESULTS: Of 45 neuromas, 80% (36/45) were end-bulb neuromas and 20% (9/45) were spindle-type neuromas. Eighty percent of the neuromas (36/45) were heterogeneous on T2-weighted images (WIs). Enlarged fascicles were present in 42% (19/45) and dark outer rims in 27% (12/45) of the neuromas. Among the 23 neuromas with enhanced images, 78% (18/23) showed enhancement. Heterogeneity on T2-WIs and enhancement ratios were significantly different between the asymptomatic and symptomatic neuroma groups (p < 0.05). The multivariate analyses indicated that heterogeneity on T2-WIs was an independent factor associated with symptomatic neuromas (p < 0.001). CONCLUSIONS: Heterogeneity on T2-WIs could be a predictive indicator for symptomatic neuromas in lower extremity amputees. KEY POINTS: • Amputation neuromas are classified as either end-bulb or spindle-type. They can show enlarged fascicles, dark outer rims, and enhancement. • Heterogeneity on T2-weighted images could be a predictive indicator for symptomatic neuromas. • Predicting the symptomatic neuroma on MRI would help in effective management of stump pain.

Does Bone Mineral Density Differ between Fan-Beam and Pencil-Beam?: A Meta-Analysis and Systemic Review.

BACKGROUND: Dual energy X-ray absorptiometry (DXA) has evolved from pencil-beam (PB) to narrow fan-beam (FB) densitometers. We performed a meta-analysis of the available observational studies to determine how different modes of DXA affect bone mineral density (BMD) measurements. METHODS: A total of 1,233 patients (808 women) from 14 cohort studies were included. We evaluated the differences in BMD according to the DXA mode: PB and FB. Additionally, we evaluated the differences in BMD between the 2 types of FB mode: FB (Prodigy) and the most recent FB (iDXA). Pairwise meta-analysis was performed, and weighted mean differences (WMD) were calculated for (total lumbar, total hip, and total body). RESULTS: No significant difference was observed in total lumbar (pooled WMD, -0.013; P=0.152) and total hip BMD (pooled WMD, -0.01; P=0.889), between PB and FB. However, total body BMD was significantly lower in the PB compared to the FB group (pooled WMD, -0.014; P=0.024). No significant difference was observed in lumbar BMD (pooled WMD, -0.006; P=0.567), total hip (pooled WMD, -0.002; P=0.821), and total body (pooled WMD, 0.015; P=0.109), between Prodigy and iDXA. CONCLUSIONS: The results of this study warrant the recommendation that correction equations should not be used when comparing BMD from different modes. Further research is still needed to highlight the ways in which differences between DXA systems can be minimized.

MR Imaging Characteristics of Primary T-Cell Lymphoma of the Cauda Equina: A Case Report and Literature Review.

Primary central nervous system lymphoma is a rare form of extranodal non-Hodgkin lymphoma, and primary T-cell lymphoma of the cauda equina is extremely rare. We describe a case involving a 56-year-old female who presented with low back pain and radiating leg pain for 4 months. MRI of the lumbar spine revealed an elongated, multinodular intradural lesion of approximately 10 cm from the L4 body to the S2 body level with iso-signal intensity on T1-weighted imaging, heterogeneous iso- and high-signal intensity on T2-weighted imaging, and a heterogeneous intense enhancement on gadolinium contrast-enhanced T1-weighted imaging. A peripheral T-cell lymphoma of the cauda equina was diagnosed on the basis of immunohistochemical and T-cell receptor gamma gene rearrangement analysis after intradural biopsy of the mass.

Evaluation of the ulnar nerve with shear-wave elastography: a potential sonographic method for the diagnosis of ulnar neuropathy.

PURPOSE: This study was designed to verify whether shear-wave elastography (SWE) can be used to differentiate ulnar neuropathy at the cubital tunnel from asymptomatic ulnar nerve or medial epicondylitis. An additional aim was to determine a cut-off value to identify patients with ulnar neuropathy. METHODS: This study included 10 patients with ulnar neuropathy at the cubital tunnel as confirmed with electromyography (three women and seven men; mean age, 51.9 years), 10 patients with medial epicondylitis (nine women and one man; mean age, 56.1 years), and 37 patients with asymptomatic ulnar nerve and lateral epicondylitis (21 women and 16 men; mean age, 54.0 years). Each patient underwent SWE of the ulnar nerve at the cubital tunnel, distal upper arm, and proximal forearm. RESULTS: Patients with ulnar neuropathy at the cubital tunnel exhibited significantly greater mean ulnar nerve stiffness at the cubital tunnel (66.8 kPa) than controls with medial epicondylitis (21.2 kPa, P=0.015) or lateral epicondylitis (33.9 kPa, P=0.040). No significant differences were observed between patients and controls with regard to ulnar nerve stiffness at the distal upper arm or the proximal forearm. A stiffness of 31.0 kPa provided 100% specificity, 80.0% sensitivity, 100% positive predictive value, and 83.3% negative predictive value for the differentiation between ulnar neuropathy and medial epicondylitis. CONCLUSION: Cubital tunnel syndrome is associated with a stiffer ulnar nerve than lateral or medial epicondylitis. SWE seems to be a new, reliable, and simple quantitative diagnostic technique to aid in the precise diagnosis of ulnar neuropathy at the cubital tunnel.

Utility of Magnetic Resonance Imaging for Differentiating Necrotizing Fasciitis from Severe Cellulitis: A Magnetic Resonance Indicator for Necrotizing Fasciitis (MRINEC) Algorithm.

We developed a new magnetic resonance indicator for necrotizing fasciitis (MRINEC) algorithm for differentiating necrotizing fasciitis (NF) from severe cellulitis (SC). All adults with suspected NF between 2010 and 2018 in a tertiary hospital in South Korea were enrolled. Sixty-one patients were diagnosed with NF and 28 with SC. Among them, 34 with NF and 15 with SC underwent magnetic resonance imaging (MRI). The MRINEC algorithm, a two-step decision tree including T2 hyperintensity of intermuscular deep fascia and diffuse T2 hyperintensity of deep peripheral fascia, diagnosed NF with 94% sensitivity (95% confidence interval (CI), 80-99%) and 60% specificity (95% CI, 32-84%). The algorithm accurately diagnosed all 15 NF patients with a high (≥8) laboratory risk indicator for necrotizing fasciitis (LRINEC) score. Among the five patients with an intermediate (6-7) LRINEC score, sensitivity and specificity were 100% (95% CI, 78-100%) and 0% (95% CI, 0-84%), respectively. Finally, among the 29 patients with a low (≤5) LRINEC score, the algorithm had a sensitivity and specificity of 88% (95% CI, 62-98%) and 69% (95% CI, 39-91%), respectively. The MRINEC algorithm may be a useful adjuvant method for diagnosing NF, especially when NF is suspected in patients with a low LRINEC score.

Threshold-based quantification of fatty degeneration in the supraspinatus muscle on MRI as an alternative method to Goutallier classification and single-voxel MR spectroscopy.

BACKGROUND: Conventional fat quantification methods for rotator cuff muscles have various limitations, such as inconsistent reliabilities of the Goutallier grades and need for advanced techniques in quantitative MRI sequences. We aimed to examine a threshold-based fat quantification method in the supraspinatus muscle on standard T1-weighted MR images and compare the threshold-based method with Goutallier grades and MR spectroscopy. METHODS: We retrospectively examined 38 symptomatic patients, who underwent T1 and T2-weighted fast spin-echo MR imaging and a single voxel spin-echo MR spectroscopy. The supraspinatus muscle and fossa were manually segmented in T1-weighted sagittal images and clustering-based thresholding was applied to quantify the fat fractions in the segmented areas using custom MATLAB software. Threshold-based fat fractions were compared with the Goutallier grades and MR spectroscopy fat/water ratios. A one-way analysis of variance and Pearson correlation were tested in the MATLAB software. RESULTS: Inter-observer reliability of threshold-based fat fractions for the supraspinatus muscle and fossa were 0.977 and 0.990 respectively, whereas the reliability of the Goutallier grading was 0.798. Threshold-based fat fractions in the supraspinatus fossa were significantly different between various Goutallier grades (one-way ANOVA, p < 0.001). Threshold-based fat fractions in the supraspinatus muscle strongly correlated with the MR spectroscopy fat/water ratio (Pearson correlation R-square = 0.83). CONCLUSIONS: Threshold-based fat quantification on standard T1-weighted MR images was highly reliable and produced comparable results to conventional Goutallier grades and MR spectroscopy fat/water ratios and could serve as an alternative method for accurate fat quantification in rotator cuff muscles.

Clinical utility of fat-suppressed 3-dimensional controlled aliasing in parallel imaging results in higher acceleration sampling perfection with application optimized contrast using different flip angle evolutions MRI of the knee in adults.

OBJECTIVE: To compare htree-dimensional CAIPIRINHA SPACE and two-dimensional turbo spin echo (2D TSE) MRI in the diagnosis of knee pathology in symptomatic adult patients. METHODS: From February to September in 2018, 120 patients who underwent a knee MRI using both 3D CAIPIRINHA SPACE and 2D TSE MRI were enrolled. The signal-to-noise ratios (SNRs) and contrast-to-noise ratio (CNR) of the 2D and 3D MRI were compared using a paired t-test. Two radiologists independently evaluated both 2D and 3D MRI images using scoring systems for the menisci, ligaments, and cartilage. Intermethod, inter- and intrareader agreements were determined using an intraclass correlation coefficient (ICC). The diagnostic performance of both methods was measured in 44 patients with arthroscopy. RESULTS: The mean scan time of 3D CAIPIRINHA SPACE MRI (4' 43") was shorter than that of 2D TSE MRI (17' 27"). The mean SNR and CNR of 3D CAIPIRINHA SPACE was higher than those of 2D TSE MRI (mean difference, 3.97 of SNR and 1.58 of CNR; p < 0.001 and p = .038, respectively). Intermethod (ICC, 0.84-1.0) and inter-reader (ICC, 0.75-0.97), and intra-reader agreements (ICC, 0.87-1.0) were good or excellent. The diagnostic accuracy of 3D CAIPIRINHA SPACE sequence was equal for ligament (95.5%) and better for meniscal and cartilage evaluation (84.1% each), compared to 2D TSE MRI (79.5% each). CONCLUSION: The fat-suppressed 3D CAIPIRINHA SPACE MRI maybe useful in clinical practice for the evaluation of the knee in place of the 2D conventional MRI protocol. ADVANCES IN KNOWLEDGE: 1. The 3D CAIPIRINHA SPACE MRI of the knee joint may be acceptable to be used in clinical practice showing comparable imaging quality compared to conventional 2D TSE MRI.2. Compared with arthroscopic findings as the gold-standard, the diagnostic performance of 3D CAIPIRINHA SPACE MRI was equal or better for knee joint evaluation than that of 2D TSE MRI, as well as with shorter scan time.

Acetabular Ossicles: Epidemiology and Correlation With Femoroacetabular Impingement.

PURPOSE: To investigate (1) the prevalence, size, and location of acetabular ossicles in general population; (2) differentiation between the characteristic types of acetabular ossicles: unfused ossification centers (true os acetabuli), rim fractures, labral calcifications and loose bodies; and (3) correlation between acetabular ossicles, and femoroacetabular impingement (FAI) with symptoms. METHODS: Patients aged 16 to 60 years who underwent abdominal and pelvic computed tomography (CT) with non-orthopaedic indications in 2016 and patients who underwent hip arthroscopy surgery from 2010 to 2016 in our institution were included for asymptomatic and symptomatic groups, respectively. Two investigators evaluated CT images to find the prevalence, size, location of acetabular ossicles, and relationship with symptoms and FAI. We correlated them with types of ossicles. RESULTS: This study included 5684 patients with 11368 hips (2790 male and 2894 female; mean age, 44.3 years) for asymptomatic group, and 264 patients with 289 hips (171 male and 93 female; mean age, 34.4 years) for symptomatic group. The prevalence of ossicles in symptomatic and asymptomatic groups was 8.65% (25/289) and 3.33% (378/11,368), respectively. The distribution of ossicles types in general population were labral calcifications (55.09%), rim fractures (35.73%), unfused ossification center (1.24%), and loose bodies (7.94%). Labral calcification had the smallest size and mostly was asymptomatic. Rim fracture was correlated with FAI in general (83.33%; P < .001) but not with any types of FAI. Size of ossicles was related with symptom (895.28 vs 103.64 mm3; P < .001). CONCLUSIONS: The prevalence of acetabular ossicles in general population are 3.46%, with significantly higher prevalence of acetabular ossicles were found in symptomatic group (8.65% vs 3.33%). Size of acetabular ossicles was significantly associated with hip pain. Labral calcification was the most common type of acetabular ossicles. Significant relationship was found between rim fracture and FAI but not with any specific types of FAI. LEVEL OF EVIDENCE: Level III, Retrospective comparative study.

Evaluation of the triangular fibrocartilage: comparison of two-compartment wrist CT arthrography using the distal radioulnar and radiocarpal joints and unicompartment wrist CT arthrography using the radiocarpal joint.

OBJECTIVE: To compare the diagnostic performance of two-compartment wrist CT arthrography of the distal radioulnar and radiocarpal joints and unicompartment wrist CT arthrography of the radiocarpal joint in depiction of the triangular fibrocartilage tear. METHODS: From January 2016 to December 2017, two-compartment CT arthrography of 74 consecutive patients (36 females, 38 males; mean age, 37.2 years) and unicompartment CT arthrography of 51 consecutive patients (18 females, 33 males; mean age, 40.1 years) were obtained. All CT arthrography images were independently and blindly evaluated by two radiologists for the presence of the triangular fibrocartilage tear by grade (partial or full thickness) per its locations: central disc proper, central-peripheral junction, proximal and distal laminae of its ulnar attachment. Fisher's exact test was used for a statistical analysis, and a p-value less than 0.05 was considered as significant. The arthroscopic findings of 47 patients (34 patients with two-compartment CT arthrography and 13 patients with unicompartment CT arthrography) were evaluated for calculating sensitivity, specificity, and accuracy. RESULTS: All partial and full thickness triangular fibrocartilage tears were identified more commonly by their location except for distal laminae on two-compartment CT arthrography than were unicompartment CT arthrography (p = 0.001-0.022). Two-compartment CT arthrography had high sensitivity (90.9-100%) and low specificity (33.3-76.5%) for detecting central disc proper and proximal lamina tears, comparing with unicompartment CT arthrography. CONCLUSION: Two-compartment wrist CT arthrography is more helpful for detecting triangular fibrocartilage tears than unicompartment wrist CT arthrography. ADVANCES IN KNOWLEDGE: It could be important to evaluate the ulnar foveal insertion of the TFCC in clinical practice, which plays the most important role in DRUJ instability and ulnar-sided wrist pain. Two-compartment wrist CTA of the DRUJ and RCJ could improve diagnostic sensitivity in the TFC tear in terms of its location and torn degree over that of unicompartment wrist CTA of the RCJ. Two-compartment wrist CTA of the DRUJ and RCJ may be recommended as a diagnostic imaging, rather than unicompartment wrist CTA of the RCJ, when peripheral foveal tear of TFC is suspected, especially in young patients.

Primary Imaging Test for Suspected Traumatic Thoracolumbar Spine Injury: 2017 Guidelines by the Korean Society of Radiology and National Evidence-Based Healthcare Collaborating Agency.

The Korean Society of Radiology and the National Evidence-based Healthcare Collaborating Agency developed a primary imaging test for suspected traumatic thoracolumbar spine injury. This guideline was developed using an adaptation process involving collaboration between the development committee and the working group. The development committee, consisting of research methodology experts, established the overall plan and provided support on research methodology. The working group, composed of radiologists with expertise in musculoskeletal imaging, wrote the recommendation. The guidelines recommend that thoracolumbar spine computed tomography without intravenous contrast enhancement be the first-line imaging modality for diagnosing traumatic thoracolumbar spine injury in adults.

The superb microvascular imaging is more sensitive than conventional power Doppler imaging in detection of active synovitis in patients with rheumatoid arthritis.

OBJECTIVES: This study evaluated Superb Microvascular Imaging (SMI) technology for detection of active synovitis in patients with rheumatoid arthritis (RA). METHODS: Between June 2015 and October 2016, 56 patients with RA (42 females; mean age, 53.2 years) underwent gray-scale ultrasound (US) imaging, power Doppler imaging (PDI), and SMI for synovitis of both wrists and hands (total 22 joints), scored for each joint from grades 0 to 3. The sum of grades for 22 joints was determined for gray-scale (SYN-sum), PDI (PDI-sum), and SMI (SMI-sum) according to clinical parameters. Follow-up US was performed in 17 patients (mean interval, 251.6 days). RESULTS: The SMI-sum (7.27 ± 4.56) was significantly higher than the PDI-sum (4.38 ± 3.09, p < 0.001) and the SYN-sum (4.55 ± 3.72, p < 0.001), and was significantly correlated with the erythrocyte sedimentation rate, C-reactive protein (CRP), and Disease Activity Score-28 (DAS28)-CRP (γ = 0.409, p = 0.002; γ = 0.695, p < 0.001; γ = 0.726, p < 0.001, respectively). Moreover, in 28 patients with clinical remission, the SMI-sum (4.32 ± 2.01) was greater than the PDI-sum (2.61 ± 1.60, p < 0.001). In 17 patients with follow-up US, the SMI-sum (2.35 ± 1.73) was significantly greater than the PDI-sum (1.24 ± 1.20; p < 0.001) and was also significantly correlated with DAS28 (γ = 0.880). CONCLUSION: SMI may detect active synovitis with greater sensitivity than PDI in RA patients, even with clinical remission, and is well-correlated with inflammatory parameters during follow-up. KEY POINTS: • SMI correlated well with PDI and was more sensitive for detection of active synovitis in RA. • The SMI-sum was not only of greater value but also more strongly correlated than the PDI-sum with clinical inflammatory indicators including ESR, CRP, and DAS28 on initial and follow-up US examinations. • The SMI-sum was even significantly increased in patients with clinical remission.

Accuracy of Magnetic Resonance Imaging and Computed Tomography Arthrography in Diagnosing Acetabular Labral Tears and Chondral Lesions.

BACKGROUND: We investigated sensitivity, specificity, and accuracy of magnetic resonance imaging (MRI) and computed tomography arthrography (CTA), on the basis of arthroscopic findings, to diagnose acetabular labral tears and chondral lesions. METHODS: We retrospectively reviewed the results of MRI and subsequent CTA in 36 hips that underwent arthroscopic surgery (33 patients; 17 males [17 hips] and 16 females [19 hips]; average age, 35 years). All patients had positive impingement test results and groin pain. We analyzed sensitivity, specificity, and accuracy of MRI and CTA by comparing with the arthroscopic findings. Interobserver agreement and intraobserver reproducibility of the presence of tears and cartilage lesions on MRI and CTA were calculated using Kappa coefficients. RESULTS: The sensitivity, specificity, and accuracy of MRI for detection of acetabular labral tears by two observers were 60%, 80%, and 64%, respectively, and 65%, 70%, and 69%, respectively. The sensitivity, specificity, and accuracy of CTA for detection of labral tears by both observers were 85%, 90%, and 86%, respectively, and 92%, 80%, and 89%, respectively. However, the sensitivity and specificity of MRI for detection of acetabular chondral lesions by both observers were 36% and 84%, respectively, and 46% and 88%, respectively. The sensitivity and specificity of CTA for detecting acetabular cartilage lesions by both observers were 46% and 72%, respectively, and 64% and 72%, respectively. Intraobserver reproducibility for detection of labral tears and chondral lesions by using MRI was substantial (κ = 0.756 and κ = 0.693, respectively). Interobserver reliability for detection of labral tears and chondral lesions by using MRI was substantial (κ = 0.700 and κ = 0.875, respectively). Intraobserver reproducibility for detection of labral tears and chondral lesions by using CTA was substantial (κ = 0.832 and κ = 0.774, respectively). Interobserver reliability for detection of labral tears and chondral lesions by using CTA was high (κ = 0.886 and κ = 0.596, respectively). CONCLUSIONS: This study demonstrated that the accuracy of MRI to detect an acetabular labral tear and a chondral lesion of the hip joint was not sufficient. CTA was reliable in the diagnosis of acetabular labral tears. However, both CTA and MRI were also of limited value to detect chondral lesions.