Abstract： Objective:To analyze the failure cases of simple greater tuberosity fractures of the humerus treated with plate and screw internal fixation, summarize the reasons for internal fixation failure, and propose avoidance methods.Methods:A retrospective analysis was conducted on 59 patients with simple greater tuberosity fractures of the humerus treated with open reduction and internal fixation with plates and screws in our hospital from January 2019 to June 2022. During follow-up, 7 cases of internal fixation failure were observed. The patient′s baseline data and perioperative indicators were recorded. The fracture healing and functional recovery were followed up. The related complications were recorded and shoulder joint function was evaluated using Neer score and Constant-Murley score at 1, 3 months after surgery and the last follow-up. The pain during shoulder joint movement was evaluated using visual analogue scale (VAS).Results:The surgical process was smooth for all patients, with an average surgical time of (65.5±17.8) minutes, an average bleeding volume of (45.7±20.6) ml, and an average incision length of (6.4±3.5) cm. All patients were follow-up for a period of 12 to 30 months, with an average of (16.3±5.4) months. During the follow-up process, 52 patients experienced fracture healing, with an average healing time of (12.2±3.3) weeks. The Neer scores at postoperative 1, 3 months, and the last follow-up were (65.34±8.15) points, (75.33±9.36) points, and (89.52±11.34) points, respectively. The Constant-Murley scores were (64.44±17.25) points, (75.62±18.44) points, and (89.30±5.88) points, respectively. The VAS during the activity were (4.66±0.81) points, (2.34±1.50) points, and (1.68±0.68) points, respectively. Seven patients experienced internal fixation failure and displacement of greater tuberosity bone blocks within three months after surgery. Three patients underwent postoperative revision, and four patients underwent external fixation. During follow-up, all fractures healed.Conclusion:The internal fixation with plates and screws is an effective treatment method for simple greater tuberosity fractures of the humerus. The main causes of internal fixation failure include deviation of plate position, poor rotator cuff suture, fragmentation of tuberosity bone fragments, and improper postoperative immobilization. The clinical attention should be paid to avoiding these factors.