Ict 256 ct scanner

This study was approved by the ethics committee of The Second Hospital of Jilin University approved. Informed consent was offered by the volunteer. The CT data of the volunteer’s shoulder were collected through the Philips iCT 256 CT scanner at 156 mA and 120 kVp with a slice thickness of 0.602 mm and exported in DICOM format. MIMICS 21.0 (Materialise, Belgium) was used to reconstruct the shoulder joint. Then the shoulder joint model was exported in standardized trigonometric language (STL) format. The medial part of the scapula was truncated to improve the simulation efficiency. The type of prosthesis was customized to the shape of the patient’s bone defect and 3D printed by the prosthesis manufacturer (AK Medical, Beijing, China). Its fixation structure was the claws on the underside of the liner (Figure 3C). The reverse shoulder prosthesis used in this study consisted of a scapular component and a humeral component. The scapular component included the glenoid base and glenosphere. The humeral component included the polyethylene liner, metal tray, and shaft (Figure 3). The assembly of the prosthesis and bone was performed under the supervision of an experienced surgeon. Both the humeral component and the glenosphere were placed in a neutral position without lateralization or tilt.

This study was approved by our institutional internal review board (no. 175 in 2018). All patients and volunteers enrolled in the study provided written informed consent. 51 DDH patients and 58 normal volunteers attended in this study. 1 DDH patient was excluded due to the age. 2 volunteers were excluded due to the history of femoral fracture. At last, 50 DDH patients and 56 volunteers were adopted in this study. The inclusion criteria were listed as follows:
DDH patients:

age: >18 years

diagnosed as DDH patients without the history of femoral fracture

Normal volunteers:

age: >18 years

volunteers without the history of femoral fracture

volunteers without congenital malformation

Examinations were carried out on a Philips iCT 256 CT scanner at 156 mA and 120 kVp with a slice thickness of 0.602 mm. The CT scanning data and X-ray data were collected from 50 DDH patients and 56 normal volunteers. The DDH group consisted of DDH patients with a mean age of 53 years (age range, 23-84). The normal group consisted of normal volunteers with a mean age of 20 years (age range, 18-21). Mimics software (v19.0, Materialise, Belgium) was used to analyzed and measured VCA on 3D. The VCA on 2D could be directly measured by X-ray photographs. The upper VCA and the lower VCA were measured in both 3D and 2D methods.