INTRODUCTION: Micro-CT analysis is a powerful technique for a non-invasive evaluation of the morphometric parameters of trabecular bone samples. This elaboration requires a previous binarization of the images. A problem which arises from the binarization process is the partial volume artifact. Voxels at the external surface of the sample can contain both bone and air so thresholding operates an incorrect estimation of volume occupied by the two materials. AIM: The aim of this study is the extraction of bone volumetric information directly from the image histograms, by fitting them with a suitable set of functions. METHODS: Nineteen trabecular bone samples were extracted from femoral heads of eight patients subject to a hip arthroplasty surgery. Trabecular bone samples were acquired using micro-CT Scanner. Hystograms of the acquired images were computed and fitted by Gaussian-like functions accounting for: a) gray levels produced by the bone x-ray absorption, b) the portions of the image occupied by air and c) voxels that contain a mixture of bone and air. This latter contribution can be considered such as an estimation of the partial volume effect. RESULTS: The comparison of the proposed technique to the bone volumes measured by a reference instrument such as by a helium pycnometer show the method as a good way for an accurate bone volume calculation of trabecular bone samples.

Morphometric and architectural bone parameters change in diseases such as osteoarthritis and osteoporosis. The mechanical strength of bone is primarily influenced by bone quantity and quality. Bone quality is defined by parameters such as trabecular thickness, trabecular separation, trabecular density and degree of anisotropy that describe the micro-architectural structure of bone. Recently, many studies have validated microtomography as a valuable investigative technique to assess bone morphometry, thanks to micro-CT non-destructive, non-invasive and reliability features, in comparison to traditional techniques such as histology. The aim of this study is the analysis by micro-computed tomography of six specimens, extracted from patients affected by osteoarthritis and osteoporosis, in order to observe the tridimensional structure and calculate several morphometric parameters.

I parametri morfometrici e architetturali dell’osso subiscono cambiamenti in presenza di patologie come l’osteoartrite e l’osteoporosi. Il comportamento meccanico dell’osso è influenzato sia dalla quantità (massa ossea) che dalla qualità dell’osso. La qualità dell’osso è definita da parametri che ne caratterizzano la struttura microarchitetturale, tra i principali lo spessore, la separazione e la densità trabecolare e il grado di anisotropia. Recentemente molti studiosi hanno validato la microtomografia come tecnica d’indagine della morfometria ossea e il suo notevole sviluppo è dato dal fatto che a differenza delle tecniche classiche come l’istologia, la microtomografia non provoca il danneggiamento del campione in esame. Nel corrente studio sono stati analizzati sei campioni ossei patologici tramite microtomografia computerizzata, prendendo in esame la struttura tridimensionale e i parametri istomorfometrici.