Validation of three classification systems for posterior malleolus fractures of the ankle.

PURPOSE: A number of classification systems exist for posterior malleolar ankle fractures. The user reliability of these classification systems remains unclear. The primary aim of this study was to evaluate the reliability of three commonly utilised classification systems for fractures of the posterior malleolus. METHODS: Imaging of 60 patients across 2 hospitals with ankle fractures including a posterior malleolar fragment was identified. All patients had undergone plain radiographs and computed tomography of their injured ankle as part of their normal standard of care. 9 surgeons including pre-resident/registrar level, resident/registrar level, and attending/consultant level applied the Haraguchi, Bartonícek, and Mason classifications to these fractures, at two timepoints, at least 4 weeks apart. The order was randomised between assessments. Inter-rater reliability was assessed using Fleiss' κ and standard error (SE). Intra-rater reliability was assessed using Cohen's κ and standard error (SE). RESULTS: Inter-rater reliability (Fleiss' κ) was calculated for the Haraguchi classification as 0.588 (SE 0.023), for the Bartonícek classification as 0.626 (SE 0.019), and the Mason classification as 0.541 (SE 0.098). Intra-rater reliability (Cohen's κ) was 0.761 (SE 0.098) for the Haraguchi classification, 0.761 (SE 0.091) for the Bartonícek, classification, and 0.724 (SE 0.096) for the Mason classification. CONCLUSIONS: This study reports the inter-rater and intra-rater reliability for three classification systems for posterior malleolus fractures. Based on definitions by Landis and Koch (Biometrics 33:159-174, 1977), inter-rater reliability was rated as 'moderate' for the Haraguchi and Mason classifications and 'substantial' for the Bartonícek classification. Similarly, the intra-rater reliability was rated as 'substantial' for all three classifications.

Responses in the right posterior superior temporal sulcus show a feature-based response to facial expression.

The face-selective region of the right posterior superior temporal sulcus (pSTS) plays an important role in analysing facial expressions. However, it is less clear how facial expressions are represented in this region. In this study, we used the face composite effect to explore whether the pSTS contains a holistic or feature-based representation of facial expression. Aligned and misaligned composite images were created from the top and bottom halves of faces posing different expressions. In Experiment 1, participants performed a behavioural matching task in which they judged whether the top half of two images was the same or different. The ability to discriminate the top half of the face was affected by changes in the bottom half of the face when the images were aligned, but not when they were misaligned. This shows a holistic behavioural response to expression. In Experiment 2, we used fMR-adaptation to ask whether the pSTS has a corresponding holistic neural representation of expression. Aligned or misaligned images were presented in blocks that involved repeating the same image or in which the top or bottom half of the images changed. Increased neural responses were found in the right pSTS regardless of whether the change occurred in the top or bottom of the image, showing that changes in expression were detected across all parts of the face. However, in contrast to the behavioural data, the pattern did not differ between aligned and misaligned stimuli. This suggests that the pSTS does not encode facial expressions holistically. In contrast to the pSTS, a holistic pattern of response to facial expression was found in the right inferior frontal gyrus (IFG). Together, these results suggest that pSTS reflects an early stage in the processing of facial expression in which facial features are represented independently.