Quantitative MRI in patients with gluteal tendinopathy and asymptomatic volunteers: initial results on T1- and T2*-mapping diagnostic accuracy and correlation with clinical assessment.

OBJECTIVE: To determine if T1- and T2*-mapping of the gluteal tendons can discriminate between participants with and without clinical findings of gluteal tendinopathy (GT) and if they correlate with clinical assessment. MATERIALS AND METHODS: This prospective study was conducted between January and December 2016. MRI of the hip included spin echo, short-T1 inversion recovery, variable-flip angle, and variable echo-time gradient echo sequences. MRI studies were reviewed independently by two radiologists. Two other readers segmented the gluteal tendons and T1, mono- (T2*m) and bi-exponential T2* (short (T2*s) and long (T2*l) components) were computed. RESULTS: Ten participants with GT (median age; interquartile range: 63 (57-67) years, all women) and 9 participants without GT (57 (55-59) years, 8 women) (P = 0.06) were enrolled. The sensitivity and specificity of reader 1 for disease classification were 40% (95% confidence interval (CI): 17-61%) and 70% (CI: 47-91%), and those of reader 2 were 70% (CI: 43-86%) and 80% (CI: 53-96%), with fair inter-reader agreement (Kappa = .38). T1 values could not discriminate between the two groups. The gluteal tendons T2*m and T2*s showed diagnostic accuracy ranging from .80 to .89. The posterior gluteus medius tendon T2*m and T2*s respectively showed sensitivity and specificity of 90%, and strong correlation (Spearman's rho = -.71; P = 0.02) with the Lower Extremity Functional Scale score. CONCLUSION: Quantitative MRI could help gain new insight into healthy and diseased gluteal tendons to allow better diagnosis and treatment stratification for patients.

Radiological identification and analysis of soft tissue musculoskeletal calcifications.

Musculoskeletal calcifications are frequent on radiographs and sometimes problematic. The goal of this article is to help radiologists to make the correct diagnosis when faced with an extraosseous musculoskeletal calcification. One should first differentiate a calcification from an ossification or a foreign body and then locate the calcification correctly. Each location has a specific short differential diagnosis, with minimal further investigation necessary. Intra-tendon calcifications are most frequently associated with hydroxyapatite deposition disease (HADD). In most cases, intra-articular calcifications are caused by calcium pyrophosphate dihydrate (CPPD) crystal deposition disease. Soft tissue calcification can be caused by secondary tumoural calcinosis from renal insufficiency, or collagen vascular diseases and by vascular calcifications, either arterial or venous (phlebolith). TEACHING POINTS: • Calcifications have to be differentiated form ossification and foreign body. • A musculoskeletal MRI study must always be correlated with a radiograph. • The clinical manifestations of calcifications may sometimes mimic septic arthritis or sarcoma. • HADD and CPPD crystal deposition have a distinct appearance on radiograph. • Calcinosis is more frequently caused by chronic renal failure and scleroderma.

Rotator Cuff Tear Morphologic Parameters at Magnetic Resonance Imaging: Relationship With Muscle Atrophy and Fatty Infiltration and Patient-Reported Function and Health-Related Quality of Life.

OBJECTIVE: The aim of this study was to determine the relationship between rotator cuff tear (RCT) morphologic parameters and muscle atrophy and fatty infiltration, and patient-reported outcome measures, in patients with symptomatic full-thickness RCT. METHODS: Rotator cuff tear location, length, width, thickness, and musculotendinous junction position were assessed in 57 magnetic resonance imaging scans and correlated to the outcome measures using multivariate regression analysis. RESULTS: Supraspinatus tendon tear length (odds ratio [OR], 2.218; 95% confidence interval [CI], 1.460-3.370), supraspinatus musculotendinous junction position (OR, 2.037; 95% CI, 1.322-3.137), and infraspinatus tendon tear width (OR, 2.371; 95% CI, 1.218-4.615) were identified as the strongest determinants of supraspinatus muscle atrophy, supraspinatus muscle fatty infiltration, and infraspinatus muscle fatty infiltration, respectively. CONCLUSIONS: The extent of supraspinatus tendon and musculotendinous junction retraction influences the development of supraspinatus muscle atrophy and fatty infiltration, whereas the extent of infraspinatus tendon tear width influences the development of infraspinatus muscle fatty infiltration. Morphologic parameters defining RCT at magnetic resonance imaging did not correlate with clinical shoulder function scores.

Ultrasound-Guided Cervical Facet Joint Injections: A Viable Substitution for Fluoroscopy-Guided Injections?

OBJECTIVES: To evaluate the feasibility of ultrasound (US)-guided cervical facet injections and to identify the potential obstacles to routine use of this technique. METHODS: After Institutional Review Board approval, 4 cadavers were used in this study. Age, sex, body mass index, and neck circumference were recorded. A total of 40 facet injections were performed from C2-C3 to C6-C7 under US guidance with radiodense colored latex. Visibility of cervical tissues and the needle was graded as complete, partial, or null (no injection was performed in this case). Frontal and lateral radiographs were taken, followed by cadaveric dissection to assess contrast and the latex distribution, which were recorded as intra-articular (success), peri-articular (success), or absent (failure). A 2-tailed Fisher exact test and Pearson χ(2)test were used to evaluate difference between success and failure rates for qualitative variables. RESULTS: Seventy-eight percent (31 of 40) of US-guided facet joint injections were successful. No statistically significant differences were found regarding body mass index, neck circumference, needle caliber, operators, and between left and right sides. All failures involved C2-C3 and C6-C7 levels, and this result was statistically significant (Pearson χ(2) = 20.645; P < .001). CONCLUSIONS: Although US-guided cervical facet joint injections are feasible, substantial obstacles may prevent their routine use. The main obstacle is to effectively identify and target the correct cervical level in a prone position.

Femoroacetabular impingement: normal values of the quantitative morphometric parameters in asymptomatic hips.

OBJECTIVE: To determine the means and the reference intervals of the quantitative morphometric parameters of femoroacetabular impingement (FAI) in normal hips with high-resolution computed tomography (CT). METHODS: We prospectively included 94 adult individuals who underwent CT for thoracic, abdominal or urologic pathologies. Patients with a clinical history of hip pathology and/or with osteoarthritis on CT were excluded. We calculated means and 95% reference intervals for imaging signs of cam-type (alpha angle at 90° and 45° and femoral head-neck offset) and pincer-type impingement (acetabular version angle, lateral centre-edge angle and acetabular index). RESULTS: The 95 % reference interval limits were all far beyond the abnormal thresholds found in the literature for cam-type and to a lesser extent for pincer-type FAI. The upper limits of the reference intervals for the alpha angles (at 90°/45°) were 68°/83° (men) and 69°/84° (women), compared to thresholds from the literature (50°, 55° or 60°). Reference intervals were similar between genders for cam-type parameters, and slightly differed for pincer-type. CONCLUSION: The 95% reference intervals of morphometric measurements of FAI in asymptomatic hips were beyond the abnormal thresholds, which was especially true for cam-type FAI. Our results suggest the need for redefining the current morphometric parameters used in the diagnosis of FAI. KEY POINTS: • 95% reference intervals limits of FAI morphotype were beyond currently defined thresholds. • Reference intervals of pincer-type morphotype measurements were close to current definitions. • Reference intervals of cam-type morphotype measurements were far beyond the current definitions. • Current morphometric definitions of cam-type morphotype should be used with care.

MRI of the metatarsophalangeal joints: improved assessment with toe traction and MR arthrography.

OBJECTIVE: This study evaluates the impact of toe traction and direct MR arthrography on the assessment of articular cartilage and plantar plates of the first and second metatarsophalangeal joints. MRI of five cadaveric feet was obtained utilizing four techniques: before arthrography without and with traction and after arthrography without and with traction. CONCLUSION: The combination of toe traction and MR arthrography is perceived to be superior in the articular cartilage and plantar plate evaluation.

Small and large bowel volvulus: Clues to early recognition and complications.

Small and large bowel volvulus are uncommon causes of bowel obstruction with nonspecific clinical manifestations which may delay the diagnosis and increase morbidity. Therefore, radiologists play an important role in promptly establishing the diagnosis, recognizing underlying congenital or acquired risk factors and detecting potentially life-threatening complications. Multidetector CT performed with intravenous contrast is currently the preferred modality for the evaluation of volvulus, which is best appreciated when imaging is perpendicular to the axis of bowel rotation, hence the benefit of multiplanar reformations. In this pictorial essay we review the pathophysiology of the different types of intestinal volvulus, discuss diagnostic criteria for prompt diagnosis of volvulus and emphasize early recognition of the complications.

Compliance with fluoride supplements provided by a dental hygienist in homes of low-income parents of preschool children in Quebec.

OBJECTIVE: This study aimed to assess the compliance with fluoride supplements provided at home by a dental hygienist to mothers of at-risk preschool children. METHODS: Participants were recruited during pregnancy of low-income women. On the first visit, the mothers of 60 infants aged 6 to 9 months were handed free fluoride supplements. A questionnaire was administered at that time and after 6 and 12 months to assess compliance during the preceding week. RESULTS: At the beginning of the study, none of the mothers reported having given fluoride supplements, in comparison with 73 percent of mothers of 44 infants who received all three visits at the end of follow-up; 48 percent reported fluoride supplement use on a daily basis. CONCLUSIONS: Removal of financial and physical barriers and personal professional involvement are good strategies to achieve compliance with fluoride supplements. Further assessment regarding the possible application of this intervention to other professional or cultural contexts is warranted.