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Abstract Background Soft tissue has an important role in stabilizing the hinge point of medial closed wedge distal femoral osteotomy (MCWDFO). However, there are conflicting data on the soft tissue anatomy around the hinge point of MCWDFO and, therefore, further anatomical data are needed. The purposes of the study were to: 1) anatomically analyze the soft tissue around the hinge point of MCWDFO; 2) radiologically define the appropriate hinge point to prevent an unstable hinge fracture based on the result of the anatomical analysis; and 3) histologically analyze the soft tissue based on the result of the anatomical analysis. Methods In 20 cadaveric knees, the capsule attachment of the distal lateral side of the femur was marked with a radiopaque ball bearing. A digital planning tool was used to calculate the area of the marked capsule attachment around the ideal hinge point of MCWDFO on radiographs. The soft tissue around the hinge point was histologically examined and the periosteal thickness was measured and visualized graphically. The graph and radiograph were overlayed using image editing software, and the appropriate hinge position was determined based on the periosteal thickness. Results As a result, the periosteal thickness of the distal lateral femur tended to rapidly decrease from the metaphyseal region toward the diaphyseal region. The overlayed graph and radiograph revealed that the periosteal thickness changed in the region corresponding to the apex of the turning point of the femoral metaphysis in all cases. Conclusions In conclusion, the periosteum might support the hinge of MCWDFO within the area surrounded by the apex of the turning point of the femoral metaphysis and the upper border of the posterior part of the lateral femoral condyle.

In tunnel inspections, it is important to check for the progression of cracks and other deformations. The point clouds of tunnels are not reproducible due to accumulated errors in mobile mapping systems using GNSS/IMU navigation. Therefore, it has been impossible to confirm the progression of deformations with the original point cloud because the shapes of the acquired point clouds do not match. Therefore, the position of the point cloud has been corrected by surveying or by manual alignment of the point cloud. This was time-consuming and costly. In this paper, we propose a new positioning method for two-time difference comparisons based on a scan-matching technique that matches tunnel features and describe the evaluation results. The results of evaluation experiments show that the average error before alignment was 0.831 m. The proposed method achieves alignment with an average error of less than 0.040 m, which is unprecedentedly accurate.