Conventional versus locked plates for hip dislocation in cerebral palsy: a matched cohort analysis

PURPOSE

Bone quality of non-ambulatory patients with cerebral palsy (CP) is a matter of concern for proximal femoral varus derotational osteotomies (VDRO). Locking plates (LCP) have been designed to compensate this biological downfall. Little data exist comparing the LCP with the conventional femoral blade plate.

METHODS

We retrospectively studied 32 patients submitted to VDRO (40 hips), operated with blade plates or LCP. Groups were matched, and the minimal follow-up was 36 months. Clinical (age at surgery, sex, GMFCS class, CP patterns) and radiological characteristics (neck shaft angle [NSA], acetabular index [AI], Reimers migration index [MP] and time until bone healing), as well as postoperative complications and the cost of treatment, were evaluated.

RESULTS

Preoperative clinical characteristics and radiographic measurements were comparable, except for a higher AI in the BP group (p < 0.01). Mean follow-up was longer in the LCP group (57.35 vs 34.6 months). Mean NSA, AI and MP had comparable correction with surgery (p < 0.01). At final follow-up, dislocation recurrence speed was higher in BP group although not statistically significant (0.56% vs 0.35%/month; p = 0.29). The complication rate was similar in both groups (p > 0.05). Finally, the cost of the treatment was 62% higher in the LCP group (p = 0.01).

CONCLUSION

Our cohorts showed LCP or BP equivalence clinically and radiographically in mid-term follow-up, with the former increasing the cost of treatment by a mean of 62%. This may raise a question on the real necessity of locked implants for these operations.

LEVEL OF EVIDENCE

Level III-Retrospective comparative study.

High-resolution ultrasonography for early diagnosis of neural impairment in seropositive leprosy household contacts

Leprosy household contacts (HC) represent a high-risk group for the development of the disease. Anti-PGL-I IgM seropositivity also increases the risk of illness. Despite significant advances in leprosy control, it remains a public health problem; and early diagnosis of this peripheral neuropathy represents one of the main goals of leprosy programs. The present study was performed to identify neural impairment in leprosy HC by analyzing differences in high-resolution ultrasonographic (US) measurements of peripheral nerves between leprosy HC and healthy volunteers (HV). Seventy-nine seropositive household contacts (SPHC) and 30 seronegative household contacts (SNHC) underwent dermato-neurological examination and molecular analysis, followed by high-resolution US evaluation of cross-sectional areas (CSAs) of the median, ulnar, common fibular and tibial nerves. In addition, 53 HV underwent similar US measurements. The US evaluation detected neural thickening in 26.5% (13/49) of the SPHC and only in 3.3% (1/30) among the SNHC (p = 0.0038). The CSA values of the common fibular and tibial nerves were significantly higher in SPHC. This group also had significantly greater asymmetry in the common fibular and tibial nerves (proximal to the tunnel). SPHC presented a 10.5-fold higher chance of neural impairment (p = 0.0311). On the contrary, the presence of at least one scar from the BCG vaccine conferred 5.2-fold greater protection against neural involvement detected by US (p = 0.0184). Our findings demonstrated a higher prevalence of neural thickening in SPHC and support the role of high-resolution US in the early diagnosis of leprosy neuropathy. The combination of positive anti-PGL-I serology and absence of a BCG scar can identify individuals with greater chances of developing leprosy neuropathy, who should be referred for US examination, reinforcing the importance of including serological and imaging methods in the epidemiological surveillance of leprosy HC.

Quantitative MRI evaluation of bone marrow in sickle cell disease: relationship with haemolysis and clinical severity

AIM

To evaluate bone marrow fat fraction using the Dixon technique (FFDix) of magnetic resonance imaging (MRI) as a potential biomarker of haemolysis and clinical severity in the overall assessment and follow-up of sickle cell disease (SCD) patients.

MATERIAL AND METHODS

The present study was a cross-sectional study in which healthy individuals and SCD patients (matched for age, sex, and weight) were subjected to MRI of the lumbar spine and pelvis to quantify FFDix in the bone marrow using the Dixon technique. SCD severity was analysed by clinical and laboratory data, and an online calculator. A high degree of haemolysis was defined using the cut-off values haemoglobin (Hb) ≤10 g/dl, lactate dehydrogenase (LDH) ≥325 U/l, reticulocytes ≥3% and total bilirubin (TB) ≥1.2 mg/dl. Pearson's correlation, receiver operating characteristic (ROC) curve and binary logistic regression analysis were performed.

RESULTS

Forty-eight SCD patients (26 homozygous: HbSS and 22 compound heterozygous: HbSC) and 48 healthy individuals participated in the study. FFDix was lower in SCD patients than in the control group, showing even lower values in the HbSS subtype and patients with a higher degree of haemolysis. HbSC patients with a higher degree of haemolysis using hydroxyurea (medium dosage 9.8 mg/kg/day) had lower FFDix. ROC curves and odds ratios for detecting patients with a higher degree of haemolysis at the different FFDix measurement sites demonstrated excellent performance: iliac bones (cut-off ≤16.75%, AUC = 0.824, p<0.001), femoral heads (cut-off ≤46.7%, AUC = 0.775, p=0.001), lumbar vertebrae (cut-off ≤7.8%, AUC = 0.755, p=0.002).

CONCLUSION

Decreased FFDix is indicative of higher degree of haemolysis and SCD severity with great potential as a non-invasive biomarker contributing to the overall assessment and follow-up of SCD patients.

AGREEMENT ON MRI DIAGNOSIS IN COMPRESSIVE MALIGNANT VERTEBRAL FRACTURES

Objective

Verify interobserver and intraobserver agreement of malignant compressive vertebral fractures (MCVF) diagnosis using magnetic resonance imaging (MRI).

Methods

We retrospectively included a lumbar spine MRI of 63 patients with non-traumatic compressive vertebral fracture diagnoses. Each lumbar vertebra was classified as: without fracture, with fracture of benign characteristics, or with fracture of malignant characteristics. Two medical residents in radiology, one musculoskeletal radiologist fellow, one musculoskeletal radiologist, and two spine surgeons evaluated MRI exams, independently and blindly. Each observer performed two readings, with a 15-day interval between evaluations. A simple Kappa coefficient was used to calculate the intra and interobserver agreement. The reference standard classification was based on bone biopsy or clinical, and imaging follow-up of at least two years, for diagnostic performance analysis. Diagnostic performance was assessed by calculating sensitivity, specificity, accuracy, and positive and negative predictive values with a 95% confidence interval (CI).

Results

We observed substantial to perfect intraobserver agreement (kappa: 0.80 to 1.00) and substantial interobserver agreement (kappa 0.64 to 0.77). In general, the sensitivity for the detection of MCVF was moderate, except for the second-year radiology resident that achieved a lower sensitivity. The specificity, accuracy, and negative predictive value were high for all observers.

Conclusion

MCVF diagnosis using MRI showed substantial interobserver agreement. The second-year medical resident achieved lower sensitivity but high specificity for MCVF. Regarding the seniors, there was no statistical significance between spine surgeons and the musculoskeletal radiologist. Level of Evidence III; Diagnostic.

Avaliações do lúmen da artéria reparada em lesões do antebraço usando o teste de Allen, Doppler portátil e ultrassonografia com Doppler

Objetivo O objetivo deste estudo foi avaliar a taxa de perviedade pós-operatória de lesões arteriais do antebraço secundárias a traumatismo penetrante. As lesões foram submetidas a reparo primário e examinadas com o teste de Allen e um dispositivo Doppler portátil; posteriormente, os resultados foram confirmados à ultrassonografia com Doppler.

Métodos Dezoito pacientes foram incluídos, com um total de 19 lesões arteriais, 14 lesões ulnares e 5 lesões radiais; um paciente tinha lesões em ambos os antebraços. Todos os pacientes foram submetidos à cirurgia e três avaliações clínicas: o teste de Allen e a avaliação do fluxo sanguíneo arterial com um dispositivo portátil de Doppler na 4ª e 16ª semanas após a cirurgia e ultrassonografia com Doppler 12 semanas após o procedimento.

Resultados Na primeira avaliação clínica, 77% dos pacientes apresentavam perviedade segundo o teste de Allen e 72% apresentavam som pulsátil identificado pelo Doppler portátil. Na segunda avaliação, 61% dos pacientes apresentaram perviedade com base no teste de Allen e a taxa de som pulsátil ao Doppler portátil foi de 72%, semelhante à observada 2 meses antes. À ultrassonografia com Doppler (cerca de 12 semanas após a cirurgia), a taxa de sucesso da arteriorrafia foi de 88%. Em relação à perviedade final (avaliação por ultrassonografia com Doppler) e mecanismo de trauma, todos os pacientes com traumatismo penetrante apresentavam artérias pérvias.

Conclusão Concluímos que a avaliação clínica com um dispositivo Doppler portátil e o teste de Allen é confiável caso a artéria pérvia possa ser palpada. No entanto, a ultrassonografia pode ser necessária em caso de impossibilidade de localização de uma artéria pérvia durante o exame clínico.

Computer-Aided Diagnosis of Vertebral Compression Fractures Using Convolutional Neural Networks and Radiomics

Vertebral Compression Fracture (VCF) occurs when the vertebral body partially collapses under the action of compressive forces. Non-traumatic VCFs can be secondary to osteoporosis fragility (benign VCFs) or tumors (malignant VCFs). The investigation of the etiology of non-traumatic VCFs is usually necessary, since treatment and prognosis are dependent on the VCF type. Currently, there has been great interest in using Convolutional Neural Networks (CNNs) for the classification of medical images because these networks allow the automatic extraction of useful features for the classification in a given problem. However, CNNs usually require large datasets that are often not available in medical applications. Besides, these networks generally do not use additional information that may be important for classification. A different approach is to classify the image based on a large number of predefined features, an approach known as radiomics. In this work, we propose a hybrid method for classifying VCFs that uses features from three different sources: i) intermediate layers of CNNs; ii) radiomics; iii) additional clinical and image histogram information. In the hybrid method proposed here, external features are inserted as additional inputs to the first dense layer of a CNN. A Genetic Algorithm is used to: i) select a subset of radiomic, clinical, and histogram features relevant to the classification of VCFs; ii) select hyper-parameters of the CNN. Experiments using different models indicate that combining information is interesting to improve the performance of the classifier. Besides, pre-trained CNNs presents better performance than CNNs trained from scratch on the classification of VCFs.

Radiomic Quantification for MRI Assessment of Sacroiliac Joints of Patients with Spondyloarthritis

Spondyloarthritis (SpA) is a group of diseases primarily involving chronic inflammation of the spine and peripheral joints, as evaluated by magnetic resonance imaging (MRI). Considering the complexity of SpA, we performed a retrospective study to discover quantitative/radiomic MRI-based features correlated with SpA. We also investigated different fat-suppression MRI techniques to develop detection models for inflammatory sacroiliitis. Finally, these model results were compared with those of experienced musculoskeletal radiologists, and the concordance level was evaluated. Examinations of 46 consecutive patients were obtained using SPAIR (spectral attenuated inversion recovery) and STIR (short tau inversion recovery) MRI sequences. Musculoskeletal radiologists manually segmented the sacroiliac joints for further extraction of 230 MRI features from gray-level histogram/matrices and wavelet filters. These features were associated with sacroiliitis, SpA, and the current biomarkers of ESR (erythrocyte sedimentation rate), CRP (C-reactive protein), BASDAI (Bath Ankylosing Spondylitis Activity Index), BASFI (Bath Ankylosing Spondylitis Functional Index), and MASES (Maastricht Ankylosing Spondylitis Enthesis Score). The Mann-Whitney U test showed that the radiomic markers from both MRI sequences were associated with active sacroiliitis and with SpA and its axial and peripheral subtypes (p < 0.05). Spearman's coefficient also identified a correlation between MRI markers and data from clinical practice (p < 0.05). Fat-suppression MRI models yielded performances that were statistically equivalent to those of specialists and presented strong concordance in identifying inflammatory sacroiliitis. SPAIR and STIR acquisition protocols showed potential for the evaluation of sacroiliac joints and the composition of a radiomic model to support the clinical assessment of SpA.

Ultrasound reference values for peripheral nerve cross-sectional areas and indices in a sample of healthy individuals in Brazil

Objective

To establish peripheral nerve cross-sectional area (CSA) reference values (absolute values, measures of asymmetry, and measures of focality) for healthy individuals in Brazil.

Materials and Methods

Sixty-six healthy volunteers underwent high-resolution ultrasound of the peripheral nerves. We obtained CSA measurements for three peripheral nerves, at specific locations: the median nerve, in the carpal tunnel (MT); the ulnar nerve, at the cubital tunnel site (UT) and at the pre-tunnel site (UPT); and the common fibular nerve, near the fibular head (FH). We calculated the CSA indices between the same sites on different sides (ΔCSAs) and between the ulnar nerve tunnel and pre-tunnel sites on the same side (ΔTPT).

Results

A total of 132 neural sites were analyzed, and the following CSA values (mean ± SD, median) were obtained: MT (6.3 ± 1.9 mm², 6.0 mm²); UT (6.2 ± 1.6 mm², 6.1 mm²); UPT (5.6 ± 1.7 mm², 5.4 mm²); and FH (10.0 ± 3.7 mm², 9.9 mm²). The ΔCSA values (mean ± SD, median) were as follows: MT (0.85 ± 0.7 mm², 0.95); UT (0.81 ± 0.62 mm², 0.95); UPT (0.61 ± 0.51 mm², 0.5); and FH (1.0 ± 0.77 mm², 1.0). The ΔTPT (mean ± SD, median) was (1.0 ± 0.8 mm², 1.0).

Conclusion

Among individuals in Brazil, peripheral nerve CSA values tend to be higher among males and to increase with aging. However, the same does not appear to hold true for the ΔCSA or the ΔTPT, the exception being the difference between the right and left UT. Differences in CSA values greater than 2.5 mm² between sides or between sites along the same nerve can indicate asymmetry or focal thickening in neuropathy, respectively.

Hashtag bone: detrimental effects on bone contrast with metabolic benefits one and five years after Roux-en-Y gastric bypass

Bone loss is a potential adverse consequence of rapid and sustained weight loss after bariatric surgery. The aim of the present study was to evaluate the bone mass, body fat distribution, and metabolic parameters in women submitted to Roux-en-Y gastric bypass (RYGB). The study included the following three groups: one group of lean women (control [C] group) and two groups of obese women, one evaluated one year (B1) and the other five years (B5) after RYGB. Dual-energy X-ray absorptiometry and magnetic resonance imaging were used to determine bone mineral density (BMD; lumbar spine, total hip, and femoral neck) and abdominal fat content (subcutaneous [SAT] and visceral [VAT] adipose tissues, and intrahepatic lipids [IHL]). The BMD/body mass index ratio was lower in the B5 compared with the C group at all sites. Serum C-terminal telopeptide of type I collagen (CTX) levels were higher in the B1 and B5 groups compared with the C group. Individuals submitted to RYGB showed greater SAT but similar VAT and IHL values compared with those in the C group. However, the B5 group had higher mean parathyroid hormone levels compared with the other two groups. Individuals submitted to RYGB presented increased levels of CTX and low BMD for body weight than those in the C group, suggesting that bone catabolism is a persistent alteration associated with RYGB. In conclusion, the long-lasting metabolic benefits obtained with RYGB in obesity are counterbalanced by a persistent catabolic effect of the procedure on bone and mineral metabolism.

Magnetic resonance imaging evaluation of common peroneal nerve injury in acute and subacute posterolateral corner lesion: a retrospective study

Objective

To evaluate qualitative and quantitative magnetic resonance imaging (MRI) criteria for injury of the common peroneal nerve (CPN) in patients with acute or subacute injuries in the posterolateral corner (PLC) of the knee, as well as to evaluate the reproducibility of MRI evaluation of CPN alterations.

Materials and Methods

This was a retrospective study of 38 consecutive patients submitted to MRI and diagnosed with acute or subacute injury to the PLC of the knee (patient group) and 38 patients with normal MRI results (control group). Two musculoskeletal radiologists (designated radiologist A and radiologist B, respectively) evaluated the images. Nerve injury was classified as neurapraxia, axonotmesis, or neurotmesis. Signal strength was measured at the CPN, the tibial nerve (TN), and a superficial vein (SV). The CPN/TN and CPN/SV signal ratios were calculated. The status of each PLC structure, including the popliteal tendon, arcuate ligament, lateral collateral ligament, and biceps tendon, was classified as normal, partially torn, or completely torn, as was that of the cruciate ligaments. For the semiquantitative analysis of interobserver agreement, the kappa statistic was calculated, whereas a receiver operating characteristic (ROC) curve was used for the quantitative analysis.

Results

In the patient group, radiologist A found CPN abnormalities in 15 cases (39.4%)-neurapraxia in eight and axonotmesis in seven-whereas radiologist B found CPN abnormalities in 14 (36.8%)-neurapraxia in nine and axonotmesis in five. The kappa statistic showed excellent interobserver agreement. In the control group, the CPN/TN signal ratio ranged from 0.63 to 1.1 and the CPN/SV signal ratio ranged from 0.16 to 0.41, compared with 1.30-4.02 and 0.27-1.08, respectively, in the patient group. The ROC curve analysis demonstrated that the CPN/TN signal ratio at a cutoff value of 1.39 had high (93.3%) specificity for the identification of nerve damage, compared with 81.3% for the CPN/SV signal ratio at a cutoff value of 0.41.

Conclusion

CPN alterations are common in patients with PLC injury detected on MRI, and the level of interobserver agreement for such alterations was excellent. Calculating the CPN/TN and CPN/SV signal ratios may increase diagnostic confidence. We recommend systematic analysis of the CPN in cases of PLC injury.

Ipsilateral femoral neck and shaft fractures. When do we need further image screening of the hip?

OBJECTIVE

The objective of the present study was to identify patterns of femoral diaphyseal fractures which are associated with fractures of the ipsilateral femoral neck according to the AO classification. We propose an algorithm of investigation based on plain radiographs, recognizing cases that need additional screening with computed tomography.

PATIENTS AND METHODS

This observational retrospective study included patients with combined diaphyseal and femoral neck fractures. These patients were retrieved from a total of 1398 patients with the diagnoses of diaphyseal fractures of the femur, who were admitted to our hospital for surgical treatment between January 2009 and October 2019. All included cases had both fractures analyzed for their geometry and were classified according to the AO Classification, seeking to find a correlation between the types of fractures.

RESULTS

Sixteen diaphyseal fractures associated with ipsilateral neck fractures were detected during the period. The distribution of the diaphyseal fractures according to the AO Classification was as follows: 5 of type A3 (31,2%) 6 type B2 (37.5%), 1 type B3 (6,2%), 2 type C2 (12,5%) and 2 type C3 (12,5%). One A2 femoral fracture occurred during the surgical procedure. No type A1 fractures were detected.

CONCLUSION

The patterns of high-energy diaphyseal fractures (A3, B and C) have a higher prevalence of associated ipsilateral neck fractures. Our study suggests that routine additional methods of image investigation of femoral neck fractures may be unnecessary for diaphyseal fractures type A1 and A2.

Machine learning-based CT radiomics features for the prediction of pulmonary metastasis in osteosarcoma

OBJECTIVE

This study aims to build machine learning-based CT radiomic features to predict patients developing metastasis after osteosarcoma diagnosis.

METHODS AND MATERIALS

This retrospective study has included 81 patients with a histopathological diagnosis of osteosarcoma. The entire dataset was divided randomly into training (60%) and test sets (40%). A data augmentation technique for the minority class was performed in the training set, along with feature's selection and model's training. The radiomic features were extracted from CT's image of the local osteosarcoma. Three frequently used machine learning models tried to predict patients with lung metastases (MT) and those without lung metastases (non-MT). According to the higher area under the curve (AUC), the best classifier was chosen and applied in the testing set with unseen data to provide an unbiased evaluation of the final model.

RESULTS

The best classifier for predicting MT and non-MT groups used a Random Forest algorithm. The AUC and accuracy results of the test set were bulky (accuracy of 73% [ 95% coefficient interval (CI): 54%; 87%] and AUC of 0.79 [95% CI: 0.62; 0.96]). Features that fitted the model (radiomics signature) derived from Laplacian of Gaussian and wavelet filters.

CONCLUSIONS

Machine learning-based CT radiomics approach can provide a non-invasive method with a fair predictive accuracy of the risk of developing pulmonary metastasis in osteosarcoma patients.

ADVANCES IN KNOWLEDGE

Models based on CT radiomic analysis help assess the risk of developing pulmonary metastases in patients with osteosarcoma, allowing further studies for those with a worse prognosis.

Evaluation of variations of the glenoid attachment of the inferior glenohumeral ligament by magnetic resonance arthrography

Objective

To evaluate the anatomical variations of the attachment of the inferior glenohumeral ligament (IGHL) to the anterior glenoid rim.

Materials and Methods

This was a retrospective review of 93 magnetic resonance arthrography examinations of the shoulder. Two radiologists, who were blinded to the patient data and were working independently, read the examinations. Interobserver and intraobserver agreement were evaluated. The pattern of IGHL glenoid attachment and its position on the anterior glenoid rim were recorded.

Results

In 50 examinations (53.8%), the glenoid attachment was classified as type I (originating from the labrum), whereas it was classified as type II (originating from the glenoid neck) in 43 (46.2%). The IGHL emerged at the 4 o'clock position in 58 cases (62.4%), at the 3 o'clock position in 14 (15.0%), and at the 5 o'clock position in 21 (22.6%). The rates of interobserver and intraobserver agreement were excellent.

Conclusion

Although type I IGHL glenoid attachment is more common, we found a high prevalence of the type II variation. The IGHL emerged between the 3 o'clock and 5 o'clock positions, most commonly at the 4 o'clock position.

Manual versus semiautomatic segmentation of soft-tissue sarcomas on magnetic resonance imaging: evaluation of similarity and comparison of segmentation times

Objective

To evaluate the degree of similarity between manual and semiautomatic segmentation of soft-tissue sarcomas on magnetic resonance imaging (MRI).

Materials and Methods

This was a retrospective study of 15 MRI examinations of patients with histopathologically confirmed soft-tissue sarcomas acquired before therapeutic intervention. Manual and semiautomatic segmentations were performed by three radiologists, working independently, using the software 3D Slicer. The Dice similarity coefficient (DSC) and the Hausdorff distance were calculated in order to evaluate the similarity between manual and semiautomatic segmentation. To compare the two modalities in terms of the tumor volumes obtained, we also calculated descriptive statistics and intraclass correlation coefficients (ICCs).

Results

In the comparison between manual and semiautomatic segmentation, the DSC values ranged from 0.871 to 0.973. The comparison of the volumes segmented by the two modalities resulted in ICCs between 0.9927 and 0.9990. The DSC values ranged from 0.849 to 0.979 for intraobserver variability and from 0.741 to 0.972 for interobserver variability. There was no significant difference between the semiautomatic and manual modalities in terms of the segmentation times (p > 0.05).

Conclusion

There appears to be a high degree of similarity between manual and semiautomatic segmentation, with no significant difference between the two modalities in terms of the time required for segmentation.

Association between spinal alignment and biochemical composition of lumbar intervertebral discs assessed by quantitative magnetic resonance imaging

Background

To evaluate potential associations between spinopelvic parameters and the biochemical composition of lumbar intervertebral discs using quantitative magnetic resonance imaging in asymptomatic young adults.

Methods

Our study group comprised 93 asymptomatic volunteers aged 20-40 years (49 women and 44 men). Lumbar spine T2-weighted images and T2 relaxometry were acquired on a 1.5T MRI scanner. Spinopelvic parameters including sacral slope, pelvic tilt, pelvic incidence, lumbar lordosis, thoracic kyphosis, thoracolumbar alignment, sagittal vertical axis, spinosacral angle, C2 pelvic angle, and T1S1 and L1S1 length were measured on panoramic spine radiographs.

Results

Lumbar lordosis decrease correlates with discrete dehydration of nucleus pulposus at all lumbar levels. Also low values of sacral slope, pelvic tilt, pelvic incidence, thoracic kyphosis and spinosacral angle were associated with decrease of T2 relaxation times on annulus fibrosus.

Conclusions

In conclusion, spinopelvic parameters presented a discrete association with lumbar disc composition and water content.

Applications of the Dixon technique in the evaluation of the musculoskeletal system

The acquisition of images with suppression of the fat signal is very useful in clinical practice and can be achieved in a variety of sequences. The Dixon technique, unlike other fat suppression techniques, allows the signal of fat to be suppressed in the postprocessing rather than during acquisition, as well as allowing the visualization of maps showing the distribution of water and fat. This review of the Dixon technique aims to illustrate the basic physical principles, to compare the technique with other magnetic resonance imaging sequences for fat suppression or fat quantification, and to describe its applications in the study of diseases of the musculoskeletal system. Many variants of the Dixon technique have been developed, providing more consistent separation of the fat and water signals, as well as allowing correction for many confounding factors. It allows homogeneous fat suppression, being able to be acquired in combination with several other sequences, as well as with different weightings. The technique also makes it possible to obtain images with and without fat suppression from a single acquisition. In addition, the Dixon technique can be used as a quantitative method, allowing the proportion of tissue fat to be determined, and, in more updated versions, can quantify tissue iron.

Ex vivo vibro-acoustography characterization of osteoporosis in an experimental mice model

Background

Osteoporosis is a highly prevalent multifactorial osteometabolic disease, classically diagnosed, in vivo, by dual energy X-ray absorptiometry (DXA). This study evaluated osteoporosis, ex vivo, using vibro-acoustography (VA), an elastographic technique based on ultrasound radiation force.

Methods

Three groups of mice femurs were used: (I) control group (CG), (II) osteoporosis group (OG) and (III) treated osteoporosis group (TOG), in which the animals received pamidronate, an antiresorptive drug. Evaluation was performed in an acoustic tank, using two high frequency focused beams produced by a confocal ultrasonic transducer. A hydrophone registered the low frequency acoustic response (AR) of bone samples. We used micro-computed tomography (microCT) as the reference standard and evaluated the correlation between VA and microCT parameters.

Results

The spectral analyses of the ARs with estimated area under the curve (AUC) values (mean; st. dev.) were, respectively, 1.29e^-07 and 9.32e^-08 for the CG, 3.25e^-08 and 2.16e^-08 for the OG, and 1.50e^-07 and 8.37e^-08 for the TOG. VA differentiated the experimental groups (P<0.01) and the results were reproducible [interclass correlation coefficient (ICC): 0.43 (95% CI: 0.15-0.71)]. There was also a statistically significant association between VA and microCT connectivity (Conn.) (r=0.80; P<0.01) and connectivity density (Conn. D) (r=0.76; P<0.01).

Conclusions

These results encourage further studies aimed at evaluating the potential use of VA for the diagnosis of osteoporosis as a relatively low-cost and radiation-free alternative to DXA.

Is there a good agreement between MRI readers for Thaunat's classification in arthroscopically-proven meniscal ramp lesions?

OBJECTIVE

To describe and evaluate the reproducibility by MRI of an arthroscopically-based classification for meniscal ramp lesions. We hypothesize that MRI would present good interobserver and intraobserver reliability to evaluate meniscal ramp lesions.

MATERIALS AND METHODS

Twenty MRI of the knee with arthroscopically-proven meniscal ramp lesions were independently assessed by two skilled musculoskeletal radiologists and a third-year radiology resident. Reading was performed in a randomized and anonymous manner, in two steps, with a minimum of 1-month interval between each. Cohen's kappa coefficient statistic was used to analyze intra and interobserver reading agreement. Associate findings were also categorized.

RESULTS

From 20 subjects, 17 were male, with mean age of 35 years. MRI reading showed type IV ramp lesion as most prevalent with eight cases (37%), followed by type V - four (21%), type I - four (20%), type III - three, (16%) and type II - one (6%). Regarding ramp lesion types, intraobserver agreement was substantial for both skilled readers (Kappa = 0.72), and moderate for the less experienced reader (Kappa = 0.51); interobserver agreement was moderate. Results between most experienced readers were also analyzed in two categories: stable (types I and II) and unstable (types III, IV and V), also resulting in moderate agreement (Kappa = 0.54). Intraobserver agreement was substantial for both readers (Kappa = 0.68). The most common associate findings were joint effusion (85%), posteromedial capsular structures injury (60%), and medial meniscus extrusion (60%).

CONCLUSION

The arthroscopy classification for meniscal ramp lesions stability adapted for MRI has good reproducibility when applied by trained musculoskeletal radiologists.

Comparison between STIR and T2-weighted SPAIR sequences in the evaluation of inflammatory sacroiliitis: diagnostic performance and signal-to-noise ratio

Objective

To compare two different fat-saturated magnetic resonance imaging (MRI) techniques-STIR and T2 SPAIR-in terms of image quality, as well as in terms of their diagnostic performance in detecting sacroiliac joints (SIJ) active inflammation.

Materials and Methods

We included 69 consecutive patients with suspected spondyloarthritis undergoing MRI between 2012 and 2014. The signal-to-noise ratio (SNR) was calculated with the method recommended by the American College of Radiology. Two readers evaluated SIJ MRI following ASAS criteria to assess diagnostic performance regarding the detection of active SIJ inflammation. T1 SPIR Gd+ sequence was used as the reference standard.

Results

The mean SNR was 72.8 for the T1 SPIR Gd+ sequence, compared with 14.1 and 37.6 for the STIR and T2 SPAIR sequences, respectively. The sensitivity and specificity of STIR and SPAIR T2 sequences did not show any statistically significant differences, for the diagnosis of sacroiliitis with active inflammation.

Conclusion

Our results corroborate those in the recent literature suggesting that STIR sequences are not superior to T2 SPAIR sequences for SIJ evaluation in patients with suspected spondyloarthritis. On 1.5-T MRI, T2-weighted SPAIR sequences provide better SNRs than do STIR sequences, which reinforces that T2 SPAIR sequences may be an advantageous option for the evaluation of sacroiliitis.

Spinopelvic sagittal balance: what does the radiologist need to know?

Sagittal balance describes the optimal alignment of the spine in the sagittal plane, resulting from the interaction between the spine and lower limbs, via the pelvis. Understanding sagittal balance has gained importance, especially in the last decade, because sagittal imbalance correlates directly with disability and pain. Diseases that alter that balance cause sagittal malalignment and may trigger compensatory mechanisms. Certain radiographic parameters have been shown to be clinically relevant and to correlate with clinical scores in the evaluation of spinopelvic alignment. This article aims to provide a comprehensive review of the literature on the spinopelvic parameters that are most relevant in clinical practice, as well as to describe compensatory mechanisms of the pelvis and lower limbs.

Machine learning techniques for computer-aided classification of active inflammatory sacroiliitis in magnetic resonance imaging

Background

Currently, magnetic resonance imaging (MRI) is used to evaluate active inflammatory sacroiliitis related to axial spondyloarthritis (axSpA). The qualitative and semiquantitative diagnosis performed by expert radiologists and rheumatologists remains subject to significant intrapersonal and interpersonal variation. This encouraged us to use machine-learning methods for this task.

Methods

In this retrospective study including 56 sacroiliac joint MRI exams, 24 patients had positive and 32 had negative findings for inflammatory sacroiliitis according to the ASAS group criteria. The dataset was randomly split with ~ 80% (46 samples, 20 positive and 26 negative) as training and ~ 20% as external test (10 samples, 4 positive and 6 negative). After manual segmentation of the images by a musculoskeletal radiologist, multiple features were extracted. The classifiers used were the Support Vector Machine, the Multilayer Perceptron (MLP), and the Instance-Based Algorithm, combined with the Relief and Wrapper methods for feature selection.

Results

Based on 10-fold cross-validation using the training dataset, the MLP classifier obtained the best performance with sensitivity = 100%, specificity = 95.6% and accuracy = 84.7%, using 6 features selected by the Wrapper method. Using the test dataset (external validation) the same MLP classifier obtained sensitivity = 100%, specificity = 66.7% and accuracy = 80%.

Conclusions

Our results show the potential of machine learning methods to identify SIJ subchondral bone marrow edema in axSpA patients and are promising to aid in the detection of active inflammatory sacroiliitis on MRI STIR sequences. Multilayer Perceptron (MLP) achieved the best results.

Manual and semiautomatic segmentation of bone sarcomas on MRI have high similarity

The aims of this study were to evaluate the intra- and interobserver reproducibility of manual segmentation of bone sarcomas in magnetic resonance imaging (MRI) studies and to compare manual and semiautomatic segmentation methods. This retrospective study included twelve osteosarcoma and eight Ewing sarcoma MRI studies performed prior to any therapeutic intervention. All cases were histopathologically confirmed. Three radiologists used 3D-Slicer software to perform manual segmentation of bone sarcomas in a blinded and independent manner. One radiologist segmented manually and also performed semiautomatic segmentation with the GrowCut tool. Segmentation exercises were timed for comparison. The dice similarity coefficient (DSC) and Hausdorff distance (HD) were used to evaluate similarity between the segmentation results and further statistical analyses were performed to compare DSC, HD, and volumetric results. Manual segmentation was reproducible with intraobserver DSC varying from 0.83 to 0.97 and HD from 3.37 to 28.73 mm. Interobserver DSC of manual segmentation showed variation from 0.73 to 0.97 and HD from 3.93 to 33.40 mm. Semiautomatic segmentation compared to manual segmentation resulted in DSCs of 0.71−0.96 and HDs of 5.38−31.54 mm. Semiautomatic segmentation required significantly less time compared to manual segmentation (P value ≤0.05). Among all situations compared, tumor volumetry did not show significant statistical differences (P value >0.05). We found excellent intra- and interobserver agreement for manual segmentation of osteosarcoma and Ewing sarcoma. There was high similarity between manual and semiautomatic segmentation, with a significant reduction of segmentation time using the semiautomatic method.

Association of bone mineral density with bone texture attributes extracted using routine magnetic resonance imaging

OBJECTIVE

Dual-energy X-ray absorptiometry (DXA)-derived bone mineral density (BMD) often fails to predict fragility fractures. Quantitative textural analysis using magnetic resonance imaging (MRI) may potentially yield useful radiomic features to predict fractures. We aimed to investigate the correlation between BMD and texture attributes (TAs) extracted from MRI scans and the interobserver reproducibility of the analysis.

METHODS

Forty-nine volunteers underwent lumbar spine 1.5-T MRI and DXA. Three-dimensional (3-D) gray-level co-occurrence matrices were measured from routine sagittal T2 fast spin-echo images using the IBEX software. Twenty-two TAs were extracted from 3-D segmented L3 vertebrae. The estimated concordance coefficient was calculated using linear regression analysis. A Pearson correlation coefficient analysis was performed to evaluate the correlation between BMD and the TAs. Interobserver reproducibility was assessed with the concordance coefficient described by Lin.

RESULTS

The results revealed a fair-to-moderate significant correlation between BMD and 13 TAs (r=-0.20 to 0.39; p<0.05). Eight TAs (autocorrelation, energy, homogeneity 1, homogeneity 1.1, maximum probability, sum average, sum variance, and inverse difference normalized) negatively correlated with BMD (r=-0.20 to -0.38; p<0.05), whereas five TAs (dissimilarity, difference entropy, entropy, sum entropy, and information measure corr 1) positively correlated with BMD (r=0.29-0.39; p<0.05). The interobserver agreement was almost perfect for all significant TAs (95% confidence interval, 0.92-1.00; p<0.05).

CONCLUSION

Specific TAs could be reliably extracted from routine MRI and correlated with BMD. Our results encourage future evaluation of the potential usefulness of quantitative texture measurements from MRI scans for predicting fragility fractures.

The Impact of Computed Tomography on Decision Making in Tibial Plateau Fractures

Schatzker introduced one of the most used classification systems for tibial plateau fractures, based on plain radiographs. Computed tomography brought to attention the importance of coronal plane-oriented fractures. The goal of our study was to determine if the addition of computed tomography would affect the decision making of surgeons who usually use the Schatzker classification to assess tibial plateau fractures. Image studies of 70 patients who sustained tibial plateau fractures were uploaded to a dedicated homepage. Every patient was linked to a folder which contained two radiographic projections (anteroposterior and lateral), three interactive videos of computed tomography (axial, sagittal, and coronal), and eight pictures depicting tridimensional reconstructions of the tibial plateau. Ten attending orthopaedic surgeons, who were blinded to the cases, were granted access to the homepage and assessed each set of images in two different rounds, separated to each other by an interval of 2 weeks. Each case was evaluated in three steps, where surgeons had access, respectively to radiographs, two-dimensional videos of computed tomography, and three-dimensional reconstruction images. After every step, surgeons were asked to present how would they classify the case using the Schatzker system and which surgical approaches would be appropriate. We evaluated the inter- and intraobserver reliability of the Schatzker classification using the Kappa concordance coefficient, as well as the impact of computed tomography in the decision making regarding the surgical approach for each case, by using the chi-square test and likelihood ratio. The interobserver concordance kappa coefficients after each assessment step were, respectively, 0.58, 0.62, and 0.64. For the intraobserver analysis, the coefficients were, respectively, 0.76, 0.75, and 0.78. Computed tomography changed the surgical approach selection for the types II, V, and VI of Schatzker (p < 0.01). The addition of computed tomography scans to plain radiographs improved the interobserver reliability of Schatzker classification. Computed tomography had a statistically significant impact in the selection of surgical approaches for the lateral tibial plateau.

Ultrasonographic characterization of the ulnar collateral ligament of normal thumbs in different age groups

OBJECTIVES

The aim of this study was to perform ultrasonographic characterization of the normal ulnar collateral ligament in different age groups and compare it in men and women and in dominant and nondominant hands.

METHODS

Forty right-handed volunteers in the age groups 20-30, 31-40, 41-50, and 51-60 years without a history of trauma or surgical procedure in the studied joint were evaluated. The studied parameters were ligament length, greatest ligament thickness, ligament longitudinal section area in the longitudinal plane, distance from the aponeurosis of the adductor muscle to the metacarpal head surface and joint opening at rest and under abduction stress.

RESULTS

The results indicated that the mean values of all parameters had minor variations with age, hand dominance, and gender and were slightly higher in men than in women and in the dominant hand than the nondominant hand. However, a statistically significant difference was observed between the joint opening at rest and under stress. In terms of age, there was a small but nonsignificant decrease in the values, likely because of the natural aging process.

CONCLUSION

The low variability in the evaluated parameters indicates that large differences between sides or genders are not to be expected. A greater change is likely to indicate a pathological situation.

The effect of low-level laser therapy and physical exercise on pain, stiffness, function, and spatiotemporal gait variables in subjects with bilateral knee osteoarthritis: a blind randomized clinical trial

Objective: To evaluate the effects of individual and combination therapies (low-level laser therapy and physical exercises) on pain, stiffness, function, and spatiotemporal gait variables in subjects with bilateral knee osteoarthritis (OA).Methods: Subjects with knee OA (Grades 1-3) were evaluated and randomized into four groups: Control Group (CG), untreated; Laser Group (LG), treated with laser at 808 nm, 5.6 J; Exercise Group (EG), treated with exercise; and Laser + Exercise Group (LEG), treated with laser and exercises. The treatment was carried out twice a week for 2 months. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire was applied for evaluation and reevaluation; evaluation of spatiotemporal gait variables was performed using GAITRite equipment.Results: The EG showed significant improvement in pain (p = 0.006) and function (p = 0.01) according to WOMAC. Regarding gait variables, in intergroup analysis after 8 weeks all groups receiving intervention showed a significant increase in gait speed: LG versus CG (p = 0.03); EG versus CG (p = 0.04) and LEG versus CG (p = 0.005). Only the group treated with laser + exercise showed a significant increase (p = 0.009) in the cadence and duration of single right limb support (p = 0.04), and only the groups treated with exercise and laser + exercise showed significant decreases in the duration of right limb support (p = 0.035 and p = 0.003, respectively), compared to the CG.Conclusions: The group treated only with exercise showed improvement in WOMAC questionnaire scores. Regarding the gait variables, all groups undergoing the interventions showed increases in the gait speed compared to the CG. The laser and exercise combination therapy provided the best results for the other gait variables (cadence and duration of right limb support and duration of single right limb support).Implications for rehabilitationThere are differences in gait patterns in patients with knee OA, including decreased gait speed, cadence, and step length.The results shown in the present study provide additional information about the physical therapy approaches that should be chosen during clinical practical to improve gait performance in individuals with knee osteoarthritis.The improvement in gait performance is a relevant issue due to the fact that is associated to physical independence and better quality of life.

Relationship of spinal alignment with muscular volume and fat infiltration of lumbar trunk muscles

Fat infiltration and atrophy of lumbar muscles are related to spinal degenerative conditions and may cause functional deficits. Spinal alignment exerts biomechanical influence on lumbar intervertebral discs and joints. Our objective was to evaluate if spinopelvic parameters correlate with the lumbar muscle volume and fat infiltration. This is an observational, prospective and cross-sectional study. Ninety-three asymptomatic adult aged 20–40 years were included. Lumbar lordosis (LL), thoracic kyphosis (TK), pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), thoracolumbar alignment (TL), sagittal vertical axis (SVA), C2-pelvic angle (CPA), spinosacral angle (SSA), lack of lordosis (PI-LL), L1S1 and T1S1 length were measured on panoramic spine radiographs. Lumbar axial T1-weighted and In- and Out-Phase images were obtained on 1.5T MRI scanner and were used to extract the muscle volumes and fat fractions of multifidus, erector spinae, and psoas. All muscle volumes were higher in men than women (p<0.05). The fat fraction was higher in the multifidus and erector spinae in women (p<0.05). Multifidus volume was weakly correlated with PT (R = 0.22), PI (R = 0.22), LL (R = 0.34) and CPA (R = 0.29). Erectors spinae volume were correlated with CPA (R = 0.21). Psoas volume correlated with TK (R = 0.21), TL (R = 0.27) and SVA (R = -0.23). The lumbar muscle volumes showed a moderated correlation with T1S1 length (R = 0.55 to 0.62). Spinopelvic parameters showed correlation with lumbar muscle volumes but not with muscle fat infiltration on asymptomatic young adults.

Integrating bilingual musculoskeletal imaging education into radiology and diagnostic imaging residency programs

Objective

To analyze the perception of the relevance of introducing bilingual (Portuguese-English) musculoskeletal imaging education into radiology and diagnostic imaging residency programs, describing the method used.

Materials and Methods

To evaluate the relevance of incorporating the bilingual study of musculoskeletal imaging into medical residency programs, we administered a questionnaire, consisting of several multiple-choice questions and one subjective question, to 21 radiology residents at a private tertiary hospital. The residents completed the questionnaire voluntarily and anonymously.

Results

Integrating English teaching into radiology training was considered important by 95.2% of the residents. Approximately 90% of residents believe that the method applied at their institution is suitable for learning.

Conclusion

The introduction of the English language into the teaching of musculoskeletal imaging in the radiology residency program was perceived positively by the residents, and the preceptors effectively supported those activities.

Ischiofemoral impingement secondary to valgus intertrochanteric osteotomy: a case report

We report an unusual case of ischiofemoral impingement secondary to valgus intertrochanteric osteotomy. The osteotomy was performed for treatment of epiphysiolysis of the left femoral head.

The pubo-femoral distance decreases with Pavlik harness treatment for developmental dysplasia of the hip in newborns

OBJECTIVE

To evaluate the evolution of the ultrasonographic pubo-femoral distance (PFD) before and after Pavlik harness treatment for developmental dysplasia of the hip (DDH) in newborns.

PATIENTS AND METHODS

Twenty-five patients (16.7 ± 10.4 days; 19 females, six males) diagnosed with DDH and treated using the Pavlik harness were included. Eighteen patients had bilateral, and seven unilateral DDH, with a total of 43 dysplastic hips. The seven non-dysplastic hips in unilateral cases were used for comparison. The PFD was measured in the coronal and axial planes with the hip flexed to approximately 90°, before and after an average of 93 days of treatment. The femoral head coverage was assessed in the coronal plane, and correlated with PFD values.

RESULTS

In dysplastic hips, the mean PFD decreased from 6.1 ± 1.8 mm to 3.0 ± 0.7 mm in the axial (adjusted difference, 2.9 mm; p < 0.01), and from 5.9 ± 2.0 to 3.0 ± 0.6 mm in the coronal plane (adjusted difference 2.7 mm; p < 0.01). The femoral head coverage increased from 30.8 to 62.1%, and the mean differences of femoral head coverage and PFD were significantly correlated (p < 0.001). There was no difference between treated dysplastic and non-dysplastic hips. There was high intra- and inter-observer agreement for PFD measurements.

CONCLUSION

The PFD decreased significantly after DDH treatment using the Pavlik harness in newborns, and showed significant correlation with the femoral head coverage improvement. PFD might be a reliable tool for monitoring DDH treatment in newborns treated using the Pavlik harness.

Reduced bone mass and preserved marrow adipose tissue in patients with inflammatory bowel diseases in long-term remission

Bone marrow adipose tissue has not been studied in patients with inactive inflammatory bowel disease. We found that these patients have preserved marrow adiposity even with low bone mass. Factors involved in bone loss in active disease may have long-lasting effects but do not seem to affect bone marrow adiposity.

INTRODUCTION

Reduced bone mass is known to occur at varying prevalence in patients with inflammatory bowel diseases (IBD) because of inflammation, malnutrition, and steroid therapy. Osteoporosis may develop in these patients as the result of an imbalanced relationship between osteoblasts and adipocytes in bone marrow. This study aimed to evaluate for the first time bone mass and bone marrow adipose tissue (BMAT) in a particular subgroup of IBD patients characterized by long-term, steroid-free remission.

METHODS

Patients with Crohn's disease (CD; N = 21) and ulcerative colitis (UC; N = 15) and controls (C; N = 65) underwent dual X-ray energy absorptiometry and nuclear magnetic resonance spectroscopy of the L3 lumbar vertebra for BMAT assessment.

RESULTS

Both the CD and UC subgroups showed significantly higher proportions of patients than controls with Z-score ≤-2.0 at L1-L4 (C 1.54%; CD 19.05%; UC 20%; p = 0.02), but not at other sites. The proportions of CD patients with a T-score ˂-1.0 at the femoral neck (C 18.46%; CD 47.62%; p = 0.02) and total hip (C 16.92%; CD 42.86%; p = 0.03) were significantly higher than among controls. There were no statistically significant differences between IBD patients and controls regarding BMAT at L3 (C 28.62 ± 8.15%; CD 29.81 ± 6.90%; UC 27.35 ± 9.80%; p = 0.67).

CONCLUSIONS

IBD patients in long-term, steroid-free remission may have a low bone mass in spite of preserved BMAT. These findings confirm the heterogeneity of bone disorders in IBD and may indicate that factors involved in bone loss in active disease may have long-lasting effects on these patients.

Reproducibility of abdominal fat assessment by ultrasound and computed tomography

Objective:

To test the accuracy and reproducibility of ultrasound and computed tomography (CT) for the quantification of abdominal fat in correlation with the anthropometric, clinical, and biochemical assessments.

Materials and Methods:

Using ultrasound and CT, we determined the thickness of subcutaneous and intra-abdominal fat in 101 subjects-of whom 39 (38.6%) were men and 62 (61.4%) were women-with a mean age of 66.3 years (60-80 years). The ultrasound data were correlated with the anthropometric, clinical, and biochemical parameters, as well as with the areas measured by abdominal CT.

Results:

Intra-abdominal thickness was the variable for which the correlation with the areas of abdominal fat was strongest (i.e., the correlation coefficient was highest). We also tested the reproducibility of ultrasound and CT for the assessment of abdominal fat and found that CT measurements of abdominal fat showed greater reproducibility, having higher intraobserver and interobserver reliability than had the ultrasound measurements. There was a significant correlation between ultrasound and CT, with a correlation coefficient of 0.71.

Conclusion:

In the assessment of abdominal fat, the intraobserver and interobserver reliability were greater for CT than for ultrasound, although both methods showed high accuracy and good reproducibility.

Sciatic neuropathy: findings on magnetic resonance neurography

Injuries of the sciatic nerve are common causes of pain and limitation in the lower limbs. Due to its particular anatomy and its long course, the sciatic nerve is often involved in diseases of the pelvis or leg. In recent years, magnetic resonance neurography has become established as an important tool for the study of peripheral nerves and can be widely applied to the study of the sciatic nerve. Therefore, detailed knowledge of its anatomy and of the most prevalent diseases affecting it is essential to maximizing the accuracy of diagnostic imaging.

Diagnostic performance of magnetic resonance imaging in the assessment of periosteal reactions in bone sarcomas using conventional radiography as the reference

Objective:

To evaluate the performance of magnetic resonance imaging (MRI) in detecting periosteal reactions and to compare MRI and conventional radiography (CR) in terms of the classification of periosteal reactions.

Materials and Methods:

Retrospective study of 42 consecutive patients (mean age, 22 years; 20 men) with a confirmed diagnosis of osteosarcoma or Ewing's sarcoma, MRI and CR images having been acquired pretreatment. Three blinded radiologists detected periosteal reactions and evaluated each periosteal reaction subtype in CR and MRI images: Codman's triangle; laminated; and spiculated. The CR was used as a benchmark to calculate the diagnostic performance. We used the kappa coefficient to assess interobserver reproducibility. A two-tailed Fisher's exact test was used in order to assess contingency between CR and MRI classifications.

Results:

In the detection of periosteal reactions, MRI showed high specificity, a high negative predictive value, and low-to-moderate sensitivity. For CR and for MRI, the interobserver agreement for periosteal reaction was almost perfect, whereas, for the classification of different subtypes of periosteal reaction, it was higher for the Codman's triangle subtype and lower for the spiculated subtype. There was no significant difference between MRI and CR in terms of the classifications (p < 0.05).

Conclusion:

We found no difference between MRI and CR in terms of their ability to classify periosteal reactions. MRI showed high specificity and almost perfect interobserver agreement for the detection of periosteal reactions. The interobserver agreement was variable for the different subtypes of periosteal reaction.

Safety, osseointegration, and bone ingrowth analysis of PMMA-based porous cement on animal metaphyseal bone defect model

Bone defects created after curettage of benign bone tumors are customarily filled with solid poly(methyl methacrylate) (PMMA) or other bone substitutes. In this study, we depicted a porous PMMA-based cement (produced by mixing sodium bicarbonate and citric acid) and evaluated the prospect of its clinic application. Cement samples were characterized by high-performance liquid chromatography (HPLC) coupled to mass spectrometry and its cytotoxicity evaluated in fibroblast cultures. Implantation in rabbits allowed the histologic analysis of bone, kidneys, and liver for toxicity and coagulation tests, and MRI images for hemostasis evaluation. Osseointegration was analyzed through radiography, microtomography (micro-CT), SEM, and histology of sheep specimens. Rabbit specimens were analyzed 1, 4, and 7 days after implantation of porous or solid bone cement in 6.0 mm femoral defects. Sheep specimens were analyzed 3 and 6 months after implantation or not of porous or solid cement in 15.0 mm subchondral tibial defects. The production process did not release any detectable toxic substance but slightly reduced fibroblast proliferation in vitro. Until 7 days after surgery, no local or systemic alterations could be detected in histology, or hematoma formation in histology or MRI. Sheep implants showed 6 mm linear ingrowth from the bone-cement interface and 20% bone ingrowth considering the whole defect area. Radiography, micro-CT, SEM, and histology confirmed these findings. We conclude that our porous PMMA-based cement is an attractive alternative treatment for bone defect filling that combines osseointegration and early weight bearing. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 649-658, 2018.

Leprosy with ulnar nerve abscess: ultrasound findings in a child

We report the ultrasound findings of a typical case of nerve abscess due to leprosy in an 11-year-old boy. The patient had previously undergone pediatric multibacillary leprosy multidrug therapy (MDT) in accordance with World Health Organization guidelines. He presented to our service with bilateral ulnar neuritis with no response to prednisone (1 mg/kg). Right ulnar nerve ultrasound revealed nerve hypoechogenicity, fascicular pattern disorganization, marked fusiform thickening, and a round anechoic area suggestive of intraneural abscess. Intense intraneural power Doppler signal was detected, indicating active neuritis. Intravenous methylprednisolone had a poor response and the patient was submitted to ulnar nerve decompression, which confirmed nerve abscess with purulent discharge during surgery. As the patient weighed more than 40 kg, treatment with a pediatric dose was considered insufficient and adult-dose MDT was prescribed, with improvement of nerve pain and function. Although leprosy is rare in developed countries, it still exists in the USA and it is endemic in many developing countries. Leprosy neuropathy is responsible for the most serious complications of the disease, which can lead to irreversible impairments and deformities. Nerve abscess is an uncommon complication of leprosy and ultrasound can efficiently demonstrate this condition, allowing for prompt treatment. There is scant literature about the imaging findings of nerve abscess in leprosy patients. Radiologists should suspect leprosy in patients with no other known causes of neuropathy when detecting asymmetric nerve enlargement and nerve abscess on ultrasound.

Ultrasonography of Leprosy Neuropathy: A Longitudinal Prospective Study

BACKGROUND

Previous studies have shown that leprosy multi-drug therapy (MDT) does not stop the progression of nerve function impairment. There are no prospective studies investigating the evolution of nerve anatomic abnormalities after treatment. We examined leprosy patients aiming to investigate the evolution of nerve ultrasonography (US) abnormalities and the risk factors for poor outcomes after MDT.

METHODOLOGY/PRINCIPAL FINDINGS

We performed bilateral US of the ulnar (U), median (M) and common fibular (CF) nerves in 9 paucibacillary (PB) and 64 multibacillary (MB) patients before and after MDT. Forty-two patients had leprosy reactions (type 1, type 2, acute neuritis) during the study. We analyzed nerve maximum cross-sectional areas (CSA), echogenicity and Doppler signal. Poor outcomes included a post-treatment CSA above normal limits with a reduction of less than 30% (U, M) or 40% (CF) from the baseline, echogenicity abnormalities or intraneural Doppler in the post-treatment study. We found that PB and patients without reactions showed significant increases in CSA at CF, whereas MB and patients with reactions had CSA reduction in some nerves after treatment (p<0.05). Despite this reduction, we observed a greater frequency of poor CSA outcomes in the MB compared to the PB (77.8% and 40.6%; p>0.05) and in the patients with reactions compared to those without (66.7% and 38.7%; p<0.05). There was significantly higher odds ratio (7.75; 95%CI: 1.56-38.45) for poor CSA outcomes only for M nerve in patients with reactions. Poor echogenicity outcomes were more frequent in MB (59.4%) compared to PB (22.2%) (p<0.05). There was significant association between poor Doppler outcomes and neuritis. Gender, disease duration, and leprosy classification were not significant risk factors for poor outcomes in CSA, echogenicity or Doppler.

CONCLUSIONS/SIGNIFICANCE

US nerve abnormalities can worsen after treatment despite the leprosy classification or the presence of reactions.

Association Between Lumbar Spine Sagittal Alignment and L4-L5 Disc Degeneration Among Asymptomatic Young Adults

STUDY DESIGN

Cross-sectional observational study on the relationship between the degrees of disc degeneration and sagittal alignment in asymptomatic healthy individuals.

OBJECTIVE

This study sought to determine whether the sagittal spine alignment subtype is related to the prevalence of lumbar disc degeneration.

SUMMARY AND BACKGROUND DATA

Sagittal balance and spinopelvic parameters might be risk factors for disc degeneration.

METHODS

A total of 70 asymptomatic participants (36 women and 34 men) without regular physical activity were categorized according to the four subtypes of sagittal alignment proposed by Roussouly. All participants underwent magnetic resonance imaging of the lumbar spine (1.5T) and panoramic radiography of the spine. The degree of disc degeneration was graded using T2-weighted images according to the Pfirrmann classification. Spinopelvic parameters and vertebral curvatures were measured on digital panoramic radiographs using Surgimap software. Interobserver analyses for the Pfirrmann classification and spinopelvic parameters were assessed using the weighted Kappa and intraclass correlation coefficient (ICC), respectively.

RESULTS

The Kappa associated with disc degeneration classification was 0.79 (95% confidence intervals 0.72-0.87). The ICCs were excellent, with small confidence intervals for all spinopelvic parameters. The type II group (flat lordosis) showed a higher frequency of degenerated discs at L4-L5 (P = 0.03) than the type IV group (long and curved lumbar spine). No significant differences in disc degeneration were observed among the four subtypes at the other disc levels. We found a negative, moderate correlation between the spinopelvic parameters and the occurrence of disc degeneration in the type II group.

CONCLUSION

The Roussouly subtype II sagittal alignment is significantly associated with disc degeneration at L4-L5 in asymptomatic young adults. Our results support the hypothesis that spinal sagittal alignment plays a role in early disc degeneration.

LEVEL OF EVIDENCE

3.

Lumbar intervertebral discs T2 relaxometry and T1ρ relaxometry correlation with age in asymptomatic young adults

BACKGROUND

To investigate the detection of intervertebral disc (IVD) composition aging-related changes using T2 and T1ρ relaxometry in vivo in asymptomatic young adults.

METHODS

We recruited ninety asymptomatic and young adults (42 men and 48 women) between 20 and 40 years old. T2 and T1ρ lumbar spine mappings were acquired using 1.5 T magnetic resonance imaging (MRI) scanner. Two independent observers manually segmented 450 lumbar discs in all slices. They also performed sub region segmentation of annulus fibrosus (AF) and nucleus pulposus (NP) at the central MRI sagittal slices.

RESULTS

There was no difference between men and women for T2 (P=0.37) or T1ρ relaxometry (P=0.97). There was a negative correlation between age (20-40 years) and IVD T2 relaxation time of the whole disc (r=-0.30, P<0.0001), NP (r=-0.20 to -0.51, P<0.05) and posterior AF (r=-0.21 to -0.31, P<0.05) at all lumbar disc levels. There was no statistical correlation between aging and IVD T1ρ relaxation both for NP and AF.

CONCLUSIONS

T2 relaxometry detected gradual IVD dehydration in the first two decades of adulthood. We observed no significant variation of T1ρ or volumetry with aging in our study group. Our results suggest that T2 mapping may be more appropriate to detect early IVD aging changes.

Imaging assessment of glenohumeral dysplasia secondary to brachial plexus birth palsy

Objective

To assess imaging parameters related to the morphology of the glenohumeral joint in children with unilateral brachial plexus birth palsy (BPBP), in comparison with those obtained for healthy shoulders.

Materials and Methods

We conducted a retrospective search for cases of unilateral BPBP diagnosed at our facility. Only patients with a clinical diagnosis of unilateral BPBP were included, and the final study sample consisted of 10 consecutive patients who were assessed with cross-sectional imaging. The glenoid version, the translation of the humeral head, and the degrees of glenohumeral dysplasia were assessed.

Results

The mean diameter of the affected humeral heads was 1.93 cm, compared with 2.33 cm for those of the normal limbs. In two cases, there was no significant posterior displacement of the humeral head, five cases showed posterior subluxation of the humeral head, and the remaining three cases showed total luxation of the humeral head. The mean glenoid version angle of the affected limbs (90-α) was -9.6º, versus +1.6º for the normal, contralateral limbs.

Conclusion

The main deformities found in this study were BPBP-associated retroversion of the glenoid cavity, developmental delay of the humeral head, and posterior translation of the humeral head.

Cervical pedicle morphometry in a Latin American population: A Brazilian study

The goal of this study was to conduct a detailed computed tomography (CT) assessment in the Brazilian population of the screw starting point, trajectory, and dimensions of pedicle in the cervical spine.Two hundred consecutive patients were retrospectively evaluated using cervical spine CT, with imaging reconstruction of each cervical vertebrae in the axial plane with 2 mm, and in sagittal reconstructions with 3 mm. Parameters in axial plane included the pedicle width (PW), pedicle axis length (PAL), pedicle transverse angle (PTA), and the distance from the entry point to the point between the lamina and spinous process (DEP). Measurements in the sagittal plane involved the pedicle height (PH) and the pedicle sagittal angle (PSA).The mean PW and PH were smaller in females than in males in all cervical vertebrae, but there were no significant differences of PTA among genders. PSA ranged from 15.2° to 23.7°. Mean values of PAL and DEP had a tendency to decrease from the proximal to distal cervical vertebrae. PW was <4 mm in 7.5% of men (C3) and 25% of women (C3), and <4.5 mm in 20% (C3 male) and 66% (C3 female). The intra- and inter-observer reliability were very good for the tomographic measurement of PW, and good for PH. For PAL, the intraobserver reliability was good, but the interobserver reliability varied from moderate to good. Considering PTA and PSA, the intraobserver reliability was good, but the interobserver reliability moderate for PTA and poor or fair for PSA. DEP measurements showed poor intraobserver reliability, and poor or moderate interobserver reliability.Our results presented similar trend of previous studies, but the frequency of patients with PW <4.5 mm in our population is higher, suggesting an increased risk during the attempting of transpedicular screw technique.

Diagnostic performance of 3D TSE MRI versus 2D TSE MRI of the knee at 1.5 T, with prompt arthroscopic correlation, in the detection of meniscal and cruciate ligament tears

Objective

To compare the diagnostic performance of the three-dimensional turbo spin-echo (3D TSE) magnetic resonance imaging (MRI) technique with the performance of the standard two-dimensional turbo spin-echo (2D TSE) protocol at 1.5 T, in the detection of meniscal and ligament tears.

Materials and Methods

Thirty-eight patients were imaged twice, first with a standard multiplanar 2D TSE MR technique, and then with a 3D TSE technique, both in the same 1.5 T MRI scanner. The patients underwent knee arthroscopy within the first three days after the MRI. Using arthroscopy as the reference standard, we determined the diagnostic performance and agreement.

Results

For detecting anterior cruciate ligament tears, the 3D TSE and routine 2D TSE techniques showed similar values for sensitivity (93% and 93%, respectively) and specificity (80% and 85%, respectively). For detecting medial meniscal tears, the two techniques also had similar sensitivity (85% and 83%, respectively) and specificity (68% and 71%, respectively). In addition, for detecting lateral meniscal tears, the two techniques had similar sensitivity (58% and 54%, respectively) and specificity (82% and 92%, respectively). There was a substantial to almost perfect intraobserver and interobserver agreement when comparing the readings for both techniques.

Conclusion

The 3D TSE technique has a diagnostic performance similar to that of the routine 2D TSE protocol for detecting meniscal and anterior cruciate ligament tears at 1.5 T, with the advantage of faster acquisition.

Shape, texture and statistical features for classification of benign and malignant vertebral compression fractures in magnetic resonance images

PURPOSE

Vertebral compression fractures (VCFs) result in partial collapse of vertebral bodies. They usually are nontraumatic or occur with low-energy trauma in the elderly secondary to different etiologies, such as insufficiency fractures of bone fragility in osteoporosis (benign fractures) or vertebral metastasis (malignant fractures). Our study aims to classify VCFs in T1-weighted magnetic resonance images (MRI).

METHODS

We used the median sagittal planes of lumbar spine MRIs from 63 patients (38 women and 25 men) previously diagnosed with VCFs. The lumbar vertebral bodies were manually segmented and statistical features of gray levels were computed from the histogram. We also extracted texture and shape features to analyze the contours of the vertebral bodies. In total, 102 lumbar VCFs (53 benign and 49 malignant) and 89 normal lumbar vertebral bodies were analyzed. The k-nearest-neighbor method, a neural network with radial basis functions, and a naïve Bayes classifier were used with feature selection. We compared the classification obtained by these classifiers with the final diagnosis of each case, including biopsy for the malignant fractures and clinical and laboratory follow up for the benign fractures.

RESULTS

The results obtained show an area under the receiver operating characteristic curve of 0.97 in distinguishing between normal and fractured vertebral bodies, and 0.92 in discriminating between benign and malignant fractures.

CONCLUSIONS

The proposed classification methods based on shape, texture, and statistical features have provided high accuracy and may assist in the diagnosis of VCFs.

Glenohumeral interposition of rotator cuff stumps: a rare complication of traumatic rotator cuff tear

The present report describes a case where typical findings of traumatic glenohumeral interposition of rotator cuff stumps were surgically confirmed. This condition is a rare complication of shoulder trauma. Generally, it occurs in high-energy trauma, frequently in association with glenohumeral joint dislocation. Radiography demonstrated increased joint space, internal rotation of the humerus and coracoid process fracture. In addition to the mentioned findings, magnetic resonance imaging showed massive rotator cuff tear with interposition of the supraspinatus, infraspinatus and subscapularis stumps within the glenohumeral joint. Surgical treatment was performed confirming the injury and the rotator cuff stumps interposition. It is important that radiologists and orthopedic surgeons become familiar with this entity which, because of its rarity, might be neglected in cases of shoulder trauma.

Does a small size needle puncture cause intervertebral disc changes?

PURPOSE

Small size needles have been regularly used for intradiscal injection of innocuous/potential therapeutic compounds in experimental conditions, but also in clinic procedures, such as discography. Our aim was to investigate if a 30-gauge needle could trigger observable changes on intact intervertebral discs. We compared these effects to those induced by a large size needle (21-gauge), a well-known intervertebral disc degenerative model based on needle puncture.

METHODS

Coccygeal intervertebral discs (Co8-9) of adult male Wistar rats were punctured with a 21-gauge needle, while the coccygeal levels Co7-8 and Co9-10 remained intact. The 30-gauge needle was used to inject a safe volume of saline (2 µl) on both intact (Co9-10) and punctured (Co8-9) discs. MRI and histological score were performed at 2, 15 and 42 days after procedure.

RESULTS

MRI analyses revealed significant reduction on signal intensity of 21-gauge punctured discs. Intact discs which received a saline injection through a 30-gauge needle also revealed significant alterations in the MRI signal when compared with control discs. No histological changes were observed in the intact saline injected discs at any time analyzed.

CONCLUSION

Since significant intervertebral image changes were observed with a 30-gauge needle, cautious interpretation of the pharmacological inoculation findings is required.

Asymmetric Nerve Enlargement: A Characteristic of Leprosy Neuropathy Demonstrated by Ultrasonography

Background

Neurological involvement occurs throughout the leprosy clinical spectrum and is responsible for the most feared consequences of the disease. Ultrasonography (US) provides objective measurements of nerve thickening and asymmetry. We examined leprosy patients before beginning multi-drug therapy aiming to describe differences in US measurements between classification groups and between patients with and without reactions.

Methodology/Principal Findings

Eleven paucibacillary (PB) and 85 multibacillary (MB) patients underwent nerve US. Twenty-seven patients had leprosy reactions (type 1, type 2 and/or acute neuritis) prior to US. The ulnar (at the cubital tunnel–Ut–and proximal to the tunnel–Upt), median (M) and common fibular (CF) nerves were scanned to measure cross-sectional areas (CSAs) in mm² and to calculate the asymmetry indexes ΔCSA (absolute difference between right and left CSAs) and ΔUtpt (absolute difference between Upt and Ut CSAs). MB patients showed greater (p<0.05) CSAs than PB at Ut (13.88±11.4/9.53±6.14) and M (10.41±5.4/6.36±0.84). ΔCSAs and ΔUtpt were similar between PB and MB. The CSAs, ΔCSAs and ΔUtpt were similar between PB patients with reactions compared to PB patients without reactions. MB patients with reactions showed significantly greater CSAs (Upt, Ut and M), ΔCSAs (Upt and Ut) and ΔUtpt compared to MB patients without reactions. PB and MB showed similar frequencies of abnormal US measurements. Patients with reactions had higher frequency of nerve thickening and similar frequency of asymmetry to those without reactions.

Conclusions/Significance

This is the first study to investigate differences in nerve involvement among leprosy classification groups using US before treatment. The magnitude of thickening was greater in MB and in patients with reactions. Asymmetry indexes were greater in patients with reactions and did not significantly differ between PB and MB, demonstrating that asymmetry is a characteristic of leprosy neuropathy regardless of its classification.

Leprosy is an infectious disease that affects the peripheral nerves, leading to nerve thickening, asymmetry and dysfunction; therefore, early detection of leprosy neuropathy is important for preventing deformities and disabilities. We examined peripheral nerve involvement using ultrasonography (US) in 96 leprosy patients prior to treatment, aiming to better understand differences in neuropathy patterns between leprosy classification groups and between patients with and without leprosy reactions. Patients underwent bilateral US of the ulnar (at the cubital tunnel and proximal to the tunnel), median and common fibular nerves to measure thickening and asymmetry. We found that nerve thickening was more severe in patients with a high bacillary load (multibacillary) and in those with previous reactions. Nerve asymmetry measurements were greater in the patients with previous reactions. Asymmetry did not differ significantly between the paucibacillary and multibacillary patients, demonstrating that asymmetry is a characteristic of leprosy neuropathy regardless of its classification.