The reliability of the augmented Lehnert-Schroth and Rigo classification in scoliosis management

Background: In pattern-specific scoliosis exercises and bracing, the corrective treatment plan differs according to different curve patterns. There are a limited number of studies investigating the reliability of the commonly used classifications systems.Objective: To test the reliability of the augmented Lehnert-Schroth (ALS) classification and the Rigo classification.Methods: X-rays and posterior photographs of 45 patients with scoliosis were sent by the first author to three clinicians twice at 1-week intervals. The clinicians classified images according to the ALS and Rigo classifications, and the data were analysed using SPSS V-16. Intraclass correlation coefficients (ICCs) and standard error measurement (SEM) were calculated to evaluate the inter- and intra-observer reliability.Results: The inter-observer ICC values were 0.552 (ALS), 0.452 (Rigo) for X-ray images and 0.494 (ALS), 0.518 (Rigo) for the photographs. The average intra-observer ICC value was 0.720 (ALS), 0.581 (Rigo) for the X-ray images and 0.726 (ALS) and 0.467 (Rigo) for the photographs.Conclusions: The results of our study indicate moderate inter-observer reliability for X-ray images using the ALS classification and clinical photographs using the Rigo classification. Intra-observer reliability was moderate to good for X-ray images and clinical photographs using the ALS classification and poor to moderate for X-ray and clinical photographs using the Rigo classification.Clinical implications: Pattern classifications assist in creating a plan and indication of correction in specific scoliosis physiotherapy and pattern-specific brace applications and surgical treatment. More sub-types are needed to address the individual patterns of curvature. The optimisation of curve classification will likely reduce failures in diagnosis and treatment.

Anterior instrumentation surgery for the treatment of Lenke type 1AR curve patterns

OBJECTIVE Previous studies have demonstrated that Lenke lumbar modifier A contains 2 distinct types (AR and AL), and the AR curve pattern is likely to develop adding-on (i.e., a progressive increase in the number of vertebrae included within the primary curve distally after posterior surgery). However, the results of anterior surgery are unknown. The purpose of this study was to present the surgical results in a cohort of patients undergoing scoliosis treatment for type 1AR curves and to compare anterior and posterior surgeries to consider the ideal indications and advantages of anterior surgery for type 1AR curves. METHODS Patients with a Lenke type 1 or 2 and lumbar modifier AR (L4 vertebral tilt to the right) and a minimum 2-year postoperative follow-up were included. The incidence of adding-on and radiographic data were compared between the anterior and posterior surgery groups. The numbers of levels between the end, stable, neutral, and last touching vertebra to the lower instrumented vertebra (LIV) were also evaluated. RESULTS Forty-four patients with a mean follow-up of 57 months were included. There were 14 patients in the anterior group and 30 patients in the posterior group. The main thoracic Cobb angle was not significantly different between the groups preoperatively and at final follow-up. At final follow-up, the anterior group had significantly less tilting of the LIV than the posterior group (−0.8° ± 4.5° vs 3° ± 4°). Distal adding-on was observed in no patient in the anterior group and in 6 patients in the posterior group at final follow-up (p = 0.025). In the anterior group, no LIV was set below the end vertebra, and all LIVs were set above last touching vertebra. The LIV was significantly more proximal in the anterior group than in the posterior surgery patients without adding-on for all reference vertebrae (p < 0.001). CONCLUSIONS This is the first study to investigate the surgical results of anterior surgery for Lenke type 1AR curve patterns, and it showed that anterior surgery for the curves could minimize the distal extent of the instrumented fusion without adding-on. This would leave more mobile disc space below the fusion.

Non-mass Enhancement in Breast MRI: Characterization with BI-RADS Descriptors and ADC Values

Objectives: The purpose of this study was to assess the accuracy of contrast-enhanced magnetic resonance imaging and diffusion-weighted imaging in distinguishing benign from malignant non-mass-like breast lesions. Methods: 103 lesions showing non-mass-like enhancement in 100 consecutive patients were analyzed. Distribution, internal enhancement patterns, and contrast kinetic curve patterns were classified according to the BI-RADS lexicon. Apparent diffusion coefficient (ADC) values were obtained from manually placed regions of interest (ROIs) on diffusion-weighted images. The optimal ADC value threshold for the distinction between benign and malignant lesions was determined by ROC analysis. Univariate and multivariate analyses were performed to identify independent predictors of malignancy, and the probability of malignancy was calculated for various combinations of findings. Histological diagnosis obtained by means of core needle biopsy was used as gold standard. Results: According to the univariate and multivariate analysis, odds ratios for malignancy were significantly elevated for clumped or clustered ring internal enhancement and low ADC values (p < 0.001), whereas distribution patterns and contrast kinetic patterns were not significantly correlated with benignity or malignancy. In non-mass lesions with homogeneous or heterogeneous internal enhancement and ADC values greater than 1.26×10-3mm2/s, no malignancy was detected, while all other combinations of findings had a probability of malignancy ranging from 22.2 to 76.6%. Conclusions: A combination of BI-RADS descriptors of internal enhancement and ADC values is useful for the differential diagnosis of lesions showing non-mass enhancement. Lesions with homogeneous or heterogeneous enhancement and high ADC can be followed up, while all other lesions should be biopsied. Doi: 10.28991/SciMedJ-2021-0302-1 Full Text: PDF

Characterization of Lactation Curve Patterns using Non-linear Models in Crossbred Dairy Cattle

Background: Lactation curve patterns are currently integrated in dairy cow’s management software. Lactation curve modeling is useful for monitoring individual yields for diet planning, determining optimum strategies for insemination and genetic evaluation. It also helps for predicting expected missing values on field records and gives concise summary of biological efficiency and persistency of dairy cows.Methods: The study was aimed to characterize the lactation curve pattern for crossbred dairy cattle using different non-linear models. During the period 1991 to 2018, daily milk yield (DMY) consisted of 281698 records of 750 crossbred dairy cows maintained at Livestock Farms. GADVASU, Ludhiana, were collected for the study. Different non-linear models viz. exponential decline function (EDF), parabolic exponential model (PEM), inverse polynomial model (IPM), gamma-type function (GTF), mixed log function (MLF) and Ali and Schaeffer model (ASF) were used for the analysis. The model(s) that best fit and describe the curve characteristics was selected on the basis of coefficient of determination (R2), coefficient of variation (CV), Akaike information criterion (AIC) and mean square error (MSE).Result: The study clearly revealed that the PRM gave highest fit to DMY data with R2, MSE, AIC and CV values of 98.10%, 0.087, -743.31 and 2.37%, respectively. The IPM had also best fitted the observed DMY data with highest R2 (98.05%), lower MSE (0.089), low AIC (-735.8972) and lower CV (2.40%) values. The fitting of observed DMY data with predicted DMY were also found to be higher in the MLF (R2= 96.46%, MSE= 0.159, AIC= -558.16 and CV= 3.21%) and GTF (R2= 95.85%, MSE= 0.190, AIC= -505.24 and CV= 3.50%), whilst the EDF and PEM Models depicted relatively low fit to the DMY data when compared with the other non-linear models. However, IPM and GTF models can be used for accurate prediction of daily milk yield in the crossbred cattle population because they were typical standard lactation curves.

Deflection Of Reinforced Concrete Beam Cfrp Bar With U-Wrap Cfrp Sheet as Shear Reinforcement

The purpose of this study was to understand the deflection behavior of reinforced concrete beams using GFRP bar as flexural reinforcement and GFRP sheet as shear reinforcement. The tested beams with dimensions of span length were 3000 mm, width of 150 mm and height of 250 mm of concrete quality f'c.25 MPa. The beams use GFRP bar 3D13 as flexural reinforcement and U-wrap GFRP sheet 50 mm wide with a distance of 100 mm. U-wrap GFRP sheet shear reinforcement is only installed in shear spans. The beam is loaded with two concentrated loads monotonically until it collapses. The test results show that the loaddeflection relationship of GFRP bar reinforced concrete beams with external shear reinforcement of U-wrap GFRP sheet shows two linear curve patterns. The results of the analysis show that the ACI-440.1R-06 approximation equation can be used to accurately predict the deflection in the middle of the GFRP bar reinforced concrete beam with external shear reinforcement from U-wrap GFRP sheet.