PubMed · 6928542
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1980. Dense calcaneus.. https://pubmed.ncbi.nlm.nih.gov/6928542/
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Twenty-eight patients with displaced intra-articular fractures of the calcaneus treated by open reduction and fixation were compared with 30 patients with similar fractures treated conservatively. Judged by the clinical and radiographic criteria results were more satisfactory in the surgical group than in the nonoperative group, although high rates of poor results were encountered in both groups.
The aim of this study was the evaluation of spiral-CT examinations in preoperative planning of calcaneal fractures supported by 3D reconstructions after electronic disarticulation. We examined 45 patients with 47 calcaneal fractures with diagnostic spiral-CT examinations in a prospective study. In addition to the conventional axial slices and sagittal reconstructions, 3D reconstructions prior to and after electronic disarticulation were performed and rated by orthopaedic surgeons and radiologists. The following diagnostic criteria were rated: involvement of articular facets, number of fragments and hindfoot deformities. Axial slices were considered to be the gold standard, because not all patients underwent surgical treatment. Axial slices showed involvement of 90 articular facets (100 %). Three-dimensional reformations after electronic disarticulation depicted 82 fractures (82 of 90, 91 %), sagittal reconstructions 63 fractures (63 of 90, 70 %). Three-dimensional reconstructions without electronic disarticulation showed five fractures (5 of 90, 5.5 %). The number of fragments was demonstrated best on sagittal reconstructions (two, three or four fragments); five fragments were diagnosed best on axial slices, and 3D reconstruction without electronic disarticulation showed only a very small number of fragments, due to overlaying bones. Hindfoot deformities (lateralisation, varus deformation, shortening) were demonstrated best on axial slices, except in terms of showing height reduction, which was demonstrated better on sagittal and 3D reconstructions. Three-dimensional reconstructions after electronic disarticulation support a clear understanding of the 3D position of the fragments and of their displacement in comparison with 3D reconstruction without electronic disarticulation, which is essential for an effective surgical reduction. Due to the potential manipulation of surface-oriented 3D reconstructions, regardless of whether electronic disarticulation is used, this imaging technique should not be considered in an isolated framework. Three-dimensional images without electronic disarticulation are superfluous in any case.
Measurements of broadband ultrasound attenuation (BUA) on a single sample using different devices have previously shown significant variations. We have used a new 3x3 array transducer to allow the evaluation of three new approaches to the BUA algorithms and the extent to which the variations might be reduced. Ten human os calces were measured using the array. The attenuation and its slope, the BUA, were calculated using three methods: 1. A phase sensitive approach, summing the individual signals from the multielement array in the time domain (TD); 2. a phase insensitive approach, summing the signals in the frequency domain (FD); 3. averaging of the individually measured attenuation and BUA values (AV). The TD and AV approaches resulted in slightly larger values for both attenuation (approximately 4%) and BUA (approximately 7%) than with the FD method. The differences between the TD and FD method may be due to phase cancellation. However, the three sets of results were not significantly different (p<0.05), which suggests that measurements on commercial equipment using large receiver apertures are not strongly affected by phase cancellation, averaging or scattering. Nevertheless, it is not clear if the differences observed are of clinical relevance, which should be investigated in the future. Our study shows that the 3 approaches are strongly related (r2> or =0.94), suggesting that translation may be possible between methods.