Early shoulder-girdle MRI findings in severe COVID-19-related intensive care unit-acquired weakness: a prospective cohort study.

OBJECTIVE: To describe clinical and early shoulder-girdle MR imaging findings in severe COVID-19-related intensive care unit-acquired weakness (ICU-AW) after ICU discharge. METHODS: A single-center prospective cohort study of all consecutive patients with COVID-19-related ICU-AW from November 2020 to June 2021. All patients underwent similar clinical evaluations and shoulder-girdle MRI within the first month and then 3 months (± 1 month) after ICU discharge. RESULTS: We included 25 patients (14 males; mean [SD] age 62.4 [12.5]). Within the first month after ICU discharge, all patients showed severe proximal predominant bilateral muscular weakness (mean Medical Research Council total score = 46.5/60 [10.1]) associated with bilateral, peripheral muscular edema-like MRI signals of the shoulder girdle in 23/25 (92%) patients. At 3 months, 21/25 (84%) patients showed complete or quasi-complete resolution of proximal muscular weakness (mean Medical Research Council total score > 48/60) and 23/25 (92%) complete resolution of MRI signals of the shoulder girdle, but 12/20 (60%) patients experienced shoulder pain and/or shoulder dysfunction. CONCLUSIONS: Early shoulder-girdle MRI findings in COVID-19-related ICU-AW included muscular edema-like peripheral signal intensities, without fatty muscle involution or muscle necrosis, with favorable evolution at 3 months. Precocious MRI can help clinicians distinguish critical illness myopathy from alternative, more severe diagnoses and can be useful in the care of patients discharged from intensive care with ICU-AW. KEY POINTS: • We describe the clinical and shoulder-girdle MRI findings of COVID-19-related severe intensive care unit-acquired weakness. • This information can be used by clinicians to achieve a nearly specific diagnosis, distinguish alternative diagnoses, assess functional prognosis, and select the more appropriate health care rehabilitation and shoulder impairment treatment.

Prognostic factors of the synovial sarcoma of the extremities: imaging does matter.

OBJECTIVES: Synovial sarcomas (SS) of the extremities are rare soft tissue sarcomas that are more common in young adults. We deciphered the imaging phenotype of SS with the aim to determine if imaging could provide an incremental value to currently known prognostic factors (PF)-age and histological grade-to predict long-term overall survival (OS). METHODS: This retrospective multicenter study included consecutive pediatric and adult patients with synovial sarcomas of the extremities from December 2002 to August 2020. Inclusion criteria were (i) a follow-up greater than 5 years and (ii) available pre-therapeutic MRI. A subset analysis included MRI and CT-scan. Clinical, pathological, and imaging variables were collected in all patients. The primary endpoint was to evaluate the association of these variables with OS using univariate and multivariate Cox regressions. RESULTS: Out of 428 patients screened for eligibility, 98 patients (mean age: 37.1 ± 15.2 years) were included (MRI: n = 98/98, CT scan: n = 34/98; 35%). The median OS was 75.25 months (IQR = 55.50-109.12) and thirty-six patients (n = 36/98;37%) died during follow-up. The recurrence rate was 12.2% (n =12/98). SS lesions were mostly grade 2 (57/98; 58%). On MRI, SS had a mean long-axis diameter of 67.5 ± 38.3 mm. On CT scan, 44% (15/34) were calcified. Grade (hazard ratio [HR] = 2.71; 95%CI = 1.30-5.66; p = 0.008), size of the lesions evaluated on MRI (HR = 1.02; 95% CI = 1.01-1.03; p < 0.001), and calcifications on CT scan (HR = 0.10; 95% CI = 0.02-0.50; p = 0.005) were independent PF of OS. CONCLUSIONS: This study demonstrated that imaging biomarkers can be used to predict long-term outcome in patients with SS. Strikingly, the presence of calcifications on CT scan is associated with favorable outcome and provides an incremental value over existing PF such as age, grade, and size. KEY POINTS: • Beyond its diagnostic value, MRI is a pre-operative prognostic tool in synovial sarcomas of the extremities since the size of the lesion is an important prognostic factor. • Calcifications on CT scans are independently and significantly associated with prolonged overall survival.

Interdisciplinary consensus statements on imaging of DRUJ instability and TFCC injuries.

OBJECTIVES: The purpose of this agreement was to establish evidence-based consensus statements on imaging of distal radioulnar joint (DRUJ) instability and triangular fibrocartilage complex (TFCC) injuries by an expert group using the Delphi technique. METHODS: Nineteen hand surgeons developed a preliminary list of questions on DRUJ instability and TFCC injuries. Radiologists created statements based on the literature and the authors' clinical experience. Questions and statements were revised during three iterative Delphi rounds. Delphi panelists consisted of twenty-seven musculoskeletal radiologists. The panelists scored their degree of agreement to each statement on an 11-item numeric scale. Scores of "0," "5," and "10" reflected complete disagreement, indeterminate agreement, and complete agreement, respectively. Group consensus was defined as a score of "8" or higher for 80% or more of the panelists. RESULTS: Three of fourteen statements achieved group consensus in the first Delphi round and ten statements achieved group consensus in the second Delphi round. The third and final Delphi round was limited to the one question that did not achieve group consensus in the previous rounds. CONCLUSIONS: Delphi-based agreements suggest that CT with static axial slices in neutral rotation, pronation, and supination is the most useful and accurate imaging technique for the work-up of DRUJ instability. MRI is the most valuable technique in the diagnosis of TFCC lesions. The main indication for MR arthrography and CT arthrography are Palmer 1B foveal lesions of the TFCC. CLINICAL RELEVANCE STATEMENT: MRI is the method of choice for assessing TFCC lesions, with higher accuracy for central than peripheral abnormalities. The main indication for MR arthrography is the evaluation of TFCC foveal insertion lesions and peripheral non-Palmer injuries. KEY POINTS: • Conventional radiography should be the initial imaging technique in the assessment of DRUJ instability. CT with static axial slices in neutral rotation, pronation, and supination is the most accurate method for evaluating DRUJ instability. • MRI is the most useful technique in diagnosing soft-tissue injuries causing DRUJ instability, especially TFCC lesions. • The main indications for MR arthrography and CT arthrography are foveal lesions of the TFCC.

MRI of squamous cell carcinoma of the nail apparatus: report of 6 cases.

Malignant tumors of the nail apparatus are rare and dominated by squamous cell carcinomas (SCC). Routinely, their pre-therapy imaging is limited to radiography. Our purpose is to determine the MRI characteristics in the locoregional assessment of SCC of the nail apparatus through a series of 6 consecutive cases explored by MRI and operated, carried out over a period of 12 years. IRB approval was obtained. Two in situ and 4 invasive squamous cell carcinomas were found, sex ratio was 0.5, and the age was 55 ± 10 years (mean ± SD). Most tumors showed specific signal behavior different from that of the epidermis and dermis with high signal on T2wi (5/6) and complete or partial enhancement (6/6). The mean thickness was 3.4 mm. The deep margin of the tumor with the dermis was always well defined for Bowen's disease (2/2) and blurred for invasive SCC. Localization involved the nail bed epithelium in all cases. Changes of the nail plate were detectable. Extension to lateral and posterior folds, hyponychium, cul-de-sac matrix, deep dermis, and bone was determined. MRI could be proposed as preoperative imaging of squamous cell carcinoma for locoregional assessment and guide biopsy.

Can T2-weighted Dixon fat-only images replace T1-weighted images in degenerative disc disease with Modic changes on lumbar spine MRI?

OBJECTIVES: To evaluate the diagnostic performance and interobserver agreement of a magnetic resonance imaging (MRI) protocol that only includes sagittal T2-weighted Dixon fat and water images as an alternative to a standard protocol that includes both sagittal T1-weighted sequence and T2-weighted Dixon water images as reference standard in lumbar degenerative disc disease with Modic changes. METHODS: From February 2017 to March 2019, 114 patients who underwent lumbar spine MRI for low back pain were included in this retrospective study. All MRI showed Modic changes at least at one vertebral level. Two radiologists read the standard protocol and 1 month later the alternative protocol. All MRI were assessed for Modic changes (types, location, extension) as well as structural changes (endplate defects, facet arthropathy, spinal stenosis, foraminal stenosis, Schmorl nodes, spondylolisthesis, disc bulges, and degeneration). Interobserver agreement was assessed, as well as diagnostic performance using the standard protocol as reference standard. RESULTS: Interobserver agreement was moderate to excellent (kappa ranging from 0.51 to 0.92). Diagnostic performance of the alternative protocol was good for detection of any Modic change (sensitivity = 100.00% [95% CI, 99.03-100.00]; specificity = 98.89% [95% CI, 98.02-99.44]), as well as for detection of each Modic subtype and structural variables (sensitivity respectively 100% and ranging from 88.43 to 99.75% ; specificity ranging respectively from 97.62 to 100% and 99.58 to 99.91% ). CONCLUSIONS: Combined with T2-weighted Dixon water images, T2-weighted Dixon fat images provide good diagnostic performance compared to T1-weighted images in lumbar degenerative disc disease with Modic changes, and could therefore allow for a shortened protocol. KEY POINTS: • Combined with T2-weighted Dixon water images, T2-weighted Dixon fat images (in comparison to T1-weighted sequence) can provide good diagnostic performance in lumbar degenerative disc disease with Modic changes. • Interobserver agreement of the alternative protocol including sagittal T2-weighted Dixon fat and water images was substantial to excellent for every studied variable except for facet arthropathy. • A shortened MRI protocol including T2-weighted Dixon sequence without T1-weighted sequence could be proposed in this clinical setting.

Interdisciplinary consensus statements on imaging of scapholunate joint instability.

OBJECTIVES: The purpose of this agreement was to establish evidence-based consensus statements on imaging of scapholunate joint (SLJ) instability by an expert group using the Delphi technique. METHODS: Nineteen hand surgeons developed a preliminary list of questions on SLJ instability. Radiologists created statements based on the literature and the authors' clinical experience. Questions and statements were revised during three iterative Delphi rounds. Delphi panellists consisted of twenty-seven musculoskeletal radiologists. The panellists scored their degree of agreement to each statement on an eleven-item numeric scale. Scores of '0', '5' and '10' reflected complete disagreement, indeterminate agreement and complete agreement, respectively. Group consensus was defined as a score of '8' or higher for 80% or more of the panellists. RESULTS: Ten of fifteen statements achieved group consensus in the second Delphi round. The remaining five statements achieved group consensus in the third Delphi round. It was agreed that dorsopalmar and lateral radiographs should be acquired as routine imaging work-up in patients with suspected SLJ instability. Radiographic stress views and dynamic fluoroscopy allow accurate diagnosis of dynamic SLJ instability. MR arthrography and CT arthrography are accurate for detecting scapholunate interosseous ligament tears and articular cartilage defects. Ultrasonography and MRI can delineate most extrinsic carpal ligaments, although validated scientific evidence on accurate differentiation between partially or completely torn or incompetent ligaments is not available. CONCLUSIONS: Delphi-based agreements suggest that standardized radiographs, radiographic stress views, dynamic fluoroscopy, MR arthrography and CT arthrography are the most useful and accurate imaging techniques for the work-up of SLJ instability. KEY POINTS: • Dorsopalmar and lateral wrist radiographs remain the basic imaging modality for routine imaging work-up in patients with suspected scapholunate joint instability. • Radiographic stress views and dynamic fluoroscopy of the wrist allow accurate diagnosis of dynamic scapholunate joint instability. • Wrist MR arthrography and CT arthrography are accurate for determination of scapholunate interosseous ligament tears and cartilage defects.

Hand Masses.

Hand and wrist soft tissue masses may be classified as pseudotumors, benign neoplasms, or malignant neoplasms. The vast majority of hand lesions are benign. Consideration of the location of the lesion and its imaging characteristics often leads to a specific diagnosis. Pseudotumors discussed in this article are ganglion cysts, accessory muscles, and inflammatory lesions. True tumors are described according to their tissue type: nerve sheath tumors, adipocytic tumors, so-called fibrohistiocytic tumors, pericytic tumors, and vascular lesions. We also outline the imaging features of masses encountered in the hand and wrist.

Usefulness of intravenous contrast-enhanced MRI for diagnosis of adhesive capsulitis.

OBJECTIVES: We aimed to compare the reliability and performance of MRI measures enhanced with intravenous (IV) injection of gadolinium contrast versus non-enhanced MRI measures for the diagnosis of adhesive capsulitis (AC). We also aimed to examine the association between MRI findings and clinical features in patients with AC. METHODS: MRI of 42 patients with a clinical diagnosis of AC confirmed by arthrography and that of 42 patients in a control group were retrospectively studied by 2 blinded readers. Reliability and performance of MRI findings were compared between IV contrast-enhanced measures and non-enhanced MRI measures in T2-weighted fat-saturated and T1-weighted images. MRI findings were correlated with clinical stage, etiology, and pain. RESULTS: Sensitivity (97.6%) and specificity (97.6%) of axillary-recess capsule signal enhancement for AC diagnosis were significantly superior (p = 0.02) to hyperintense signals on T2-weighted fat-suppressed images (sensitivity 90.5%, specificity 92.7%). Measures of the intensity signal in the area of the rotator interval were less performant for AC diagnosis but could be improved with joint capsule enhancement. Moreover, we found very high specificity (100%) of enhancement of the coracohumeral ligament signal for AC diagnosis. The early stage of adhesive capsulitis was positively correlated with joint capsule enhancement in the rotator interval. Secondary etiology of capsulitis was correlated with joint capsule hyperintensity signals of the rotator interval on T2-weighted fat-suppressed images. CONCLUSION: IV contrast injection with MRI can be helpful for AC diagnosis in difficult cases. The stage of AC seems related to joint capsule enhancement in the rotator interval. KEY POINTS: • IV gadolinium-enhanced MRI can improve the analysis of signal changes in the shoulder synovium and capsule of the shoulder that are related to adhesive capsulitis. • As an original finding, we observed that coracohumeral ligament enhancement had a 100% specificity for the diagnosis of adhesive capsulitis. • The intensity of enhanced signals in the rotator interval seems to be related to the early stage of frozen shoulder.

Present Status of Musculoskeletal Radiology in Europe: International Survey by the European Society of Musculoskeletal Radiology.

No official data exist on the status of musculoskeletal (MSK) radiology in Europe. The Committee for National Societies conducted an international survey to understand the status of training, subspecialization, and local practice among the European Society of Musculoskeletal Radiology (ESSR) partner societies. This article reports the results of that survey. An online questionnaire was distributed to all 26 European national associations that act as official partner societies of the ESSR. The 24 questions were subdivided into six sections: society structure, relationship with the national radiological society, subspecialization, present radiology practice, MSK interventional procedures, and MSK ultrasound. The findings of our study show a lack of standardized training and/or accreditation methods in the field of MSK radiology at a national level. The European diploma in musculoskeletal radiology is directed to partly overcome this problem; however, this certification is still underrecognized. Using certification methods, a more homogeneous European landscape could be created in the future with a view to subspecialist training. MSK ultrasound and MSK interventional procedures should be performed by a health professional with a solid knowledge of the relevant imaging modalities and sufficient training in MSK radiology. Recognition of MSK radiology as an official subspecialty would make the field more attractive for younger colleagues as well as attracting the brightest and best, an important key to further development of both clinical and academic radiology. KEY POINTS: · Standardized training and/or accreditation methods in the field of MSK radiology is lacking at a national level.. · With certification methods, such as the European diploma in musculoskeletal radiology, a more homogeneous European landscape could be created in the future with a view to subspecialist training.. · Recognition of MSK radiology as an official subspecialty would make the field more attractive for younger colleagues as well as attracting the brightest and best, an important key to further development of both clinical and academic radiology..

Intradiscal Glucocorticoid Injection for Patients With Chronic Low Back Pain Associated With Active Discopathy: A Randomized Trial.

BACKGROUND: Active discopathy is associated with a specific phenotype of chronic low back pain (LBP). Local inflammation has a role in active discopathy-associated symptoms. OBJECTIVE: To assess the efficacy of a single glucocorticoid intradiscal injection (GC IDI) in patients with chronic LBP with active discopathy. DESIGN: Prospective, parallel-group, double-blind, randomized, controlled study. (ClinicalTrials.gov: NCT00804531). SETTING: 3 tertiary care centers in France. PATIENTS: 135 patients with chronic LBP with active discopathy on magnetic resonance imaging (MRI). INTERVENTION: A single GC IDI (25 mg prednisolone acetate) during discography (n = 67) or discography alone (n = 68). MEASUREMENTS: The primary outcome was the percentage of patients with LBP intensity less than 40 on an 11-point numerical rating scale (0 [no pain] to 100 [maximum pain] in 10-point increments) in the previous 48 hours at 1 month after the intervention. The main secondary outcomes were LBP intensity and persistent active discopathy on MRI at 12 months and spine-specific limitations in activities, health-related quality of life, anxiety and depression, employment status, and use of analgesics and nonsteroidal anti-inflammatory drugs at 1 and 12 months. RESULTS: All randomly assigned patients were included in the primary efficacy analysis. At 1 month after the intervention, the percentage of responders (LBP intensity <40) was higher in the GC IDI group (36 of 65 [55.4%]) than the control group (21 of 63 [33.3%]) (absolute risk difference, 22.1 percentage points [95% CI, 5.5 to 38.7 percentage points]; P = 0.009). The groups did not differ in LBP intensity at 12 months and in most secondary outcomes at 1 and 12 months. LIMITATION: Tertiary care setting. CONCLUSION: In chronic LBP associated with active discopathy, a single GC IDI reduces LBP at 1 month but not at 12 months. PRIMARY FUNDING SOURCE: French Ministry of Health.

Fat Suppression with Dixon Techniques in Musculoskeletal Magnetic Resonance Imaging: A Pictorial Review.

Dixon techniques are part of the methods used to suppress the signal of fat in MRI. They present many advantages compared with other fat suppression techniques including (1) the robustness of fat signal suppression, (2) the possibility to combine these techniques with all types of sequences (gradient echo, spin echo) and different weightings (T1-, T2-, proton density-, intermediate-weighted sequences), and (3) the availability of images both with and without fat suppression from one single acquisition. These advantages have opened many applications in musculoskeletal imaging. We first review the technical aspects of Dixon techniques including their advantages and disadvantages. We then illustrate their applications for the imaging of different body parts, as well as for tumors, neuromuscular disorders, and the imaging of metallic hardware.

Reduction of Metal Artifact with Dual-Energy CT: Virtual Monospectral Imaging with Fast Kilovoltage Switching and Metal Artifact Reduction Software.

Imaging of patients with metal implants is a common activity for radiologists, and overcoming metal artifacts during computed tomography (CT) is still a challenge. Virtual monochromatic spectral (VMS) imaging with dual-energy CT has been reported to reduce beam-hardening metal artifact effectively. Dual-energy CT allows the synthesis of VMS images. Monochromatic images depict how the imaged object would look if the X-ray source produced X-ray photons at only a single-energy level. For this reason, VMS imaging improve image quality by reducing beam-hardening artifacts. Additional metal artifact reduction postprocessing such as metal artifact reduction software can be applied to improve the visualization of the bone-prosthesis interface, periprosthetic areas, and soft tissue near and far from the metal implant. This article summarizes how virtual monochromatic images are synthesized from dual-energy CT, and it describes and illustrates our clinical experience with a single-source dual-energy scanner with fast kilovoltage switching to reduce beam hardening in patients with metal implants.

Diagnostic imaging of benign and malignant osseous tumors of the fingers.

Primary lesions of the tubular bones of the digits are not uncommon, and the vast majority of these lesions are benign. Benign intramedullary lesions such as enchondromas are frequently discovered incidentally, unless they are associated with a pathologic fracture. Expansile lesions or lesions that are pedunculated and protrude from the cortex may manifest with pain and functional deficits from local inflammatory reactions. Systemic disorders such as sarcoidosis and local soft-tissue lesions with involvement of adjacent bone may mimic primary phalangeal bone tumors. Primary or secondary malignant lesions of the phalanges, most commonly chondrosarcomas, are extremely rare, and their characterization may require the use of multiple modalities, including radiography, computed tomography, and magnetic resonance imaging. Although ultrasonography is extremely useful in the evaluation of soft-tissue lesions of the hand, its role in the evaluation of osseous lesions is limited. The authors describe the imaging features of the most common benign osseous and chondral lesions of the fingers, including enchondromas, cystic lesions, and osteochondromas. In addition, they discuss malignant entities that may occur in the fingers (eg, chondrosarcomas and metastatic lesions) and commonly encountered mimics of primary osseous lesions (eg, glomus tumors, intraosseous epidermal inclusion cysts, infectious entities, and manifestations of systemic diseases). They also discuss the advantages and disadvantages of the most commonly used imaging modalities in differentiating benign from malignant lesions.

Evaluation of a method for the assessment of anterior acetabular coverage and hip joint space width.

OBJECTIVE: The false-profile view (FP) is an oblique view of the acetabulum and a true lateral view of femur and joint. It evaluates anterior and posterior hip joint space width (JSW) and anterior acetabular coverage using the vertical-center margin angle (VCA). The biplanar slot scanner (SS) allows simultaneous bilateral acquisitions of oblique views of hip joints. The aim of this work was to compare SS versus FP for the evaluation of VCA and JSW and to test its reproducibility and validity. MATERIALS AND METHODS: A prospective study of 28 patients (55 hips) with hip pain was performed from November 2011 until May 2012. Two readers measured VCA and JSW. JSW was normalized by the diameter of the femoral head for each technique. The radiation exposure was recorded and compared between the two modalities. Student's t test and the Pearson's correlation assessed the agreement between SS and FP. The intraclass correlation coefficient (ICC) was used to assess the interobserver agreement. RESULTS: The mean VCA angle was 32.1° (± 7.1°) and 30.3° (± 8.5°) with FP and SS, respectively. The coefficient of correlation was 0.90 (p < 0.01). The coefficient of correlation of normalized JSW was 0.83, 0.85, and 0.87 at anterior, vertical, and posterior points, respectively). The ICC was between 0.69 and 0.81 for each modality. The mean radiation exposure was 1.33 (± 0.02) mGy versus 8.69 (±0.04) mGy for FP and SS, respectively (p < 0.0001). CONCLUSIONS: SS has the potential advantages of simultaneous bilateral acquisition, higher standardization, and is less irradiating. SS is reliable for coxometry.

Hand and wrist involvement in systemic sclerosis: US features.

PURPOSE: To characterize ultrasonographic (US) features in the hand of patients with systemic sclerosis (SSc) and to evaluate the sensitivity of US in the detection of calcinosis and acroosteolysis. MATERIALS AND METHODS: The local ethics committee approved this study, and oral informed consent was obtained. A total of 44 consecutive patients with SSc (34 women; mean age, 56.1 years ± 12.1 [standard deviation]; 10 men; mean age, 45.0 years ± 14.0) and 30 healthy control subjects (20 women; mean age, 46.3 years ± 12.1; 10 men; mean age, 39.6 years ± 10.8) were included between October 2010 and December 2011. Bilateral US, including Doppler assessment of the wrists, hands, and fingers, was performed, and presence of synovitis, tenosynovitis with or without a layered appearance, calcifications, acroosteolysis, and distal vascularization was recorded. Radiography of both hands was performed to assess for acroosteolysis and calcinosis. Frequency of US features, sensitivity of US for calcinosis and acroosteolysis, and respective confidence intervals were calculated. RESULTS: Synovitis was found in 17 patients (39%). Tenosynovitis was found in 12 patients (27%), and it had a layered pattern in 15 (41%) of 37 cases. Calcinosis was found in 17 patients (39%) with US, with a sensitivity of 89%. Acroosteolysis was found in nine (20%) patients with US and in 10 (23%) patients with radiography, with 90% sensitivity for US. Distal vascularization was detected in 26 patients (59%) and 30 control subjects (100%) and was in contact with the acroosteolysis bed in seven (78%) of nine patients with SSc. CONCLUSION: US can be used to assess features of SSc, including synovitis, tenosynovitis, calcinosis, acroosteolysis, and distal vascularization and is sensitive for calcinosis and acroosteolysis detection. A layered pattern (similar to the appearance of an artichoke heart) of tenosynovitis was seen commonly. Online supplemental material is available for this article.

Radiological cervical spine involvement in young adults with polyarticular juvenile idiopathic arthritis.

OBJECTIVES: Radiological cervical spine involvement in JIA has already been assessed with a large range of prevalence (5-80%), but most studies were performed a long time ago, in symptomatic JIA and without differentiating subsets of JIA. We set out to describe structural cervical spine involvement in young adults with polyarticular JIA (pJIA) regardless of the cervical symptoms and to compare lesions with those observed in adult RA. METHODS: All consecutive pJIAs followed in a transition programme were included. Standard radiographs of the cervical spine, hands, feet and hip were analysed by two independent radiologists blinded to the diagnosis. An RA control group (<55 years), matched for sex and disease duration, was recruited. RESULTS: Fifty-seven pJIA and 58 RA patients were included. Radiographs showed cervical lesions in 65% of pJIA and 67% of RA patients. In total, 51% of pJIA with radiographic abnormalities had no clinical symptoms. In pJIA, the most frequent structural lesions were anterior atlantoaxial subluxation (33%), erosion of the odontoid process (19%), C1-C2 arthritis (17%) and apophyseal joint arthritis (16%). Cervical lesions in pJIA were similar to those in RA except for ankylosis and hypotrophia (P < 0.05). The presence of cervical lesions correlated with a more severe disease. CONCLUSION: Structural cervical spine involvement is common in pJIA persisting into adulthood, frequently asymptomatic and associated with a more severe disease. We suggest that radiographic assessment of the cervical spine should be done systematically at onset of the disease and regularly during its course regardless of clinical symptoms.

Occurrence of coring after needle insertion through a rubber stopper: study with prednisolone acetate.

OBJECTIVES: To evaluate the occurrence of coring after needle insertion through the rubber stopper of prednisolone acetate vials. METHODS: Two-hundred vials of prednisolone acetate were randomly distributed to two radiologists. Prednisolone acetate was drawn up through the rubber bung of the vials with an 18-gauge cutting bevelled needle and aspirated with a 5-ml syringe. The presence of coring was noted visually. We systematically put each core in a syringe refilled with 3 ml prednisolone acetate, and injected the medication through a 20-gauge spine needle. Computed tomography was performed to measure the size of each coring. RESULTS: Coring occurred in 21 out of 200 samples (10.5 %), and was visually detected in the syringe filled up with prednisolone in 11 of the 21 cases. Ten more occult cores were detected only after the syringes and needles were taken apart and rinsed. The core size ranged from 0.6 to 1.1 mm, and 1 of the 21 (4.7 %) cores was ejected through the 20-gauge needle. CONCLUSION: Coring can occur after the insertion of a needle through the rubber stopper of a vial of prednisolone acetate, and the resultant core can then be aspirated into the syringe.

Diffusion tensor imaging of the median nerve in recurrent carpal tunnel syndrome - initial experience.

OBJECTIVES: To investigate median nerve structure in patients with recurrent carpal tunnel syndrome (CTS) using diffusion tensor imaging (DTI) and to relate DTI changes to anatomical MRI and to measures of median nerve function. METHODS: Median nerve structure was quantified according to DTI in patients with recurrent CTS and in healthy controls of similar age. Anatomical MRI was used to identify the presence of nerve compression and fibrosis. Median nerve function was measured using electromyography, a force-tracking task (accuracy of precision grip control) and clinical measures. RESULTS: Patients showed reduced apparent diffusion coefficient (ADC), reduced axial diffusivity (AD) and radial diffusivity (RD) along the median nerve compared with controls (P < 0.001). Patients with endoneural fibrosis had the greatest reductions in ADC and in RD. ADC and AD correlated positively with nerve conduction velocity (R = 0.54 and R = 0.68, respectively) and fractional anisotropy correlated negatively with error during force-tracking (R = -0.58). CONCLUSIONS: A specific pattern of DTI changes in the median nerve was identified in patients with recurrent CTS. Fibrosis may be underlying these structural changes. The correlations with nerve conduction velocity and accuracy of force control suggest that DTI is a promising technique in the study of median nerve structure in recurrent CTS. KEY POINTS: • Diffusion tensor imaging (DTI) offers further possibilities in musculoskeletal magnetic resonance imaging. • DTI reveals median nerve changes in recurrent carpal tunnel syndrome. • DTI changes were greater with signs of median nerve fibrosis. • DTI parameters correlated with nerve conduction and force control measures. • DTI is a promising technique in recurrent carpal tunnel syndrome.

Dorsal fractures of the triquetrum: MRI findings with an emphasis on dorsal carpal ligament injuries.

OBJECTIVE: The objective of our study was to report the MRI findings in dorsal fractures of the triquetrum, with an emphasis on dorsal carpal ligament injuries. MATERIALS AND METHODS: A total of 21 patients (16 men, five women; mean age, 41.9 years) with acute or subacute (≤ 6 weeks) dorsal triquetral fractures on radiography and MRI were included in this two-center retrospective study. MRI of the wrist was performed on 3-T units with transverse T1-weighted, coronal or transverse (or both) fat-suppressed T2weighted, transverse gadolinium-enhanced fat-suppressed T1-weighted turbo spin-echo, and 3D gadolinium-enhanced fat-suppressed T1-weighted gradient-recalled echo sequences. Three musculoskeletal radiologists evaluated the ulnar styloid process index (USPI) on radiographs and the following MRI features: fracture pattern (types 1-6), bone fragment size and displacement, bone marrow edema distribution, and dorsal carpal ligament tears. RESULTS: Eight type 1, one type 2, six type 3, five type 4, and one type 5 fractures were identified. These fractures were associated with 14 (66.7%), 17 (81.0%), and 16 (76.2%) tears of the dorsal radiocarpal, ulnotriquetral, and intercarpal ligaments, respectively. There was no correlation between bone marrow edema distribution and dorsal carpal ligament injuries (all p > 0.05). The mean (± SD) bone fragment volume and displacement were 205 ± 157 mm(3) and 1.0 ± 1.1 mm, respectively. The mean USPI was 0.21 ± 0.10. CONCLUSION: Dorsal fractures of the triquetrum are frequently associated with dorsal carpal ligament injuries. Bone marrow edema distribution is not correlated with these ligament tears.