A Modular Software System for 3D Measurement of Acetabulum in Arthritic Dysplasia Hips In order to help orthopedists evaluate the morphological characteristics of the acetabulum of patients with osteoarthritis of the hip more efficiently and accurately to identify the type of acetabular deformities which benefits the personalized preoperative planning, a 3dimensional (3D) acetabular morphologic parameters measurements software dedicated to the hip was developed. The system includes four modules: 1) Identify the anterior pelvic plane (APP) of the pelvis model; 2) Identify the circular rim of the acetabular wall; 3) Automatically measure the 3D morphological parameters of the dysplastic acetabulum; 4) Interactively measure the 3D morphological parameters of the dysplastic acetabulum. The automatic parameter measurement function of this software could fast and accurately measure the 3D morphological parameters of the dysplastic acetabulum. These automatically measured parameters were close to those measured manually with error generally less than 2mm, and their average measurement time was nearly 10 times faster than that using the Mimics 17.0 system. For patients with large osteophyte, the 3D morphological parameters of the dysplastic acetabulum could be efficiently measured using the interactive measurement function of this software with simple operations. This software was used to measure acetabular morphological parameters in 61 patients. Two types of dysplastic acetabula were identified by the thickness of the medial wall on the lower margin of the acetabulum Tb: type I was a thin acetabulum (35 cases,  Tb leqslant 10.0  mm) and type II was a thick acetabulum (26 cases,  Tb u003e 10.0  mm). According to the result of the acetabular morphological characteristic analysis, it can be found that the thickness of the medial wall is an important morphological characteristic for the THA preoperative surgical planning, and the thickened medial wall could be a misleading factor for the suboptimal placement of the cup

Correlation of Vertebral Absolute Axial Rotations in CAD 3D Models of Adolescent Idiopathic Scoliosis NonInvasively Diagnosed This paper presents preliminary results on noninvasive optical diagnosis of patient with adolescent idiopathic scoliosis (AIS) with recently developed tool ScolioSIM. This tool generates intrinsic and extrinsic indicators of the spinal deformity and 3D CAD (Computeraided Design) deformity model based only on a digitalized dorsal surface of the examined patient. Our primary focus in this paper are absolute axial rotations (AAR) of each vertebra in AIS patients and their correlations. Clinical relevance of this research is high, as we intend to avoid traditional methods which rely on highly complicated reading and measuring of AARs on planar xray films, as these methods involve ionizing radiation and require highly experienced observers. Here we demonstrated a good correlation of AARs in 372 patients optically diagnosed, and currently we perform final verification of presented method and generic CAD model of the spine against 200 lowdose EOS scans of AIS patients.