2024, Vol. 28 ›› Issue (24): 3885-3889

Micro-CT analysis of distribution and structural characteristics of bone trabeculae in the calcaneus

Zhang Fengzhen1, Sun Ruifen2, Li Ziyu1, Wang Xing3, Li Kun1, Li Zhijun1, Zhang Shaojie1   

Abstract: BACKGROUND: The calcaneus is located in the lower posterior part of the foot and is heavily stressed. Calcaneus is complex and irregular in shape, surrounded by thin cortical bone and filled with a large number of trabeculae. The study of the microstructure, movement, and distribution of trabeculae is helpful to improve the understanding of calcaneus fracture.
OBJECTIVE: The image data of calcaneus were obtained by scanning the calcaneus specimens with micro-computed tomography, and the structure of trabecular bone in calcaneus was analyzed to explore the morphology, distribution and structural characteristics of trabecular bone in calcaneus.
METHODS: Dry adult calcaneus specimens were continuously scanned by micro-computed tomography, and the images were obtained after scanning and stored in DICOM format. Image data were imported into Hiscan Analyzer software to display clear and complete images of the sagittal plane, coronal plane, and the horizontal plane of the adult calcaneus. The trabecular movement of bone was observed layer by layer. According to the trabecular movement characteristics, the sagittal plane of the calcaneus was divided into six parts. A 49-mm2 region of interest was selected for each part at the same thickness as 7 mm. The three-dimensional microstructure of calcaneus and trabecular bone was obtained after three-dimensional reconstruction. After binarization, the volume fraction, surface density, trabecular thickness, trabecular space, and trabecular number parameters of the trabecular bone in the region of interest were calculated by software.
RESULTS AND CONCLUSION: (1) The cortical layer of the calcaneus was very thin and filled with a large amount of cancellous bone, and the cortical layer of the horn of Gissane was obviously thickened. (2) The trabecular volume fraction in the upper part of the calcaneus was greater than that in the anterior part of the lower part of the calcaneus, the central triangle, the posterior part of the lower part of the calcaneus, and the base of the calcaneus, and the trabecular volume fraction in the tubercle of the calcaneus was greater than that in the anterior part of the lower part of the calcaneus, the central triangle, the posterior part of the lower part of the calcaneus, and the base of the calcaneus. The surface density of the trabecular bone in the tubercle of the calcaneus was higher than that in the front of the lower calcaneus, the middle triangle area, and the bottom of calcaneus, and the surface density of the trabecular bone in the upper part of calcaneal bone, and the lower part of the calcaneus was higher than that in the middle triangle area. The thickness of the trabecular bone in the upper part of the calcaneus was greater than that in the tubercle of the calcaneal bone. The bone trabecular space in the middle triangle was larger than that in the upper part of the calcaneus and calcaneal tubercles. The number of bone trabeculae in the calcaneal tubercles was greater than that in the middle triangle area. (3) These results indicate that the trabeculae of rod bone were mainly distributed in the middle triangle area. The surface density of trabeculae was the smallest, the volume fraction was smaller, and the space between trabeculae was the largest. This part of the bone is relatively loose. The compression resistance is poor when subjected to high impact. The trabecular bone fractures first occur, which is a prone site for fractures.

Key words: Micro-CT, calcaneus, bone trabeculae, morphological characteristics, fracture