摘要Background Accurate and precise preoperative planning can provide information instrumental for performing less invasive articular fracture surgery.The purpose of this study was to determine that computer-assisted preoperative planning (CAPP) has the potential to improve efficiency and time in the operating room.Methods Sixty-four patients with proximal humeral fractures were treated using locking plates by minimally invasive plate osteosynthesis (MIPO) with CAPP.The time needed for virtual segmentation,reduction,and fixation of the fracture fragments were recorded.Intra and interobserver reliabilities were analyzed using the intraclass correlation coefficient.The clinical function was analyzed using Constant Score and radiology.Results The mean total time required for CAPP of two-part,three-part,and four-part proximal humeral fractures were (13.63±1.38) minutes,(23.14±2.18) minutes,and (39.61±3.01) minutes,respectively.The intra and interobserver reliabilities for all variables were high,ranging from 0.785 to 0.992.The mean operation time was (50.1±6.7) minutes.Fiftytwo patients were followed up with an average time of 34.2 months.The mean Constant Score of the injury side was (82.5± 9.9).Three of the fifty-two patients had four complications.Conclusion The application of CAPP was efficient and reliable,and provided excellent clinical and radiographic outcomes for the treatment of proximal humerus fractures by MIPO.