Objective:To investigate the effect of arthroscopically-assisted open reduction and internal fixation of intra-articular distal radius fracture.Methods:A retrospective cohort study was made on clinical data of 44 patients with distal radial intraarticular fracture admitted to Jing′an District Central Hospital, Fudan University between June 2017 and August 2020. There were 13 males and 31 females, at age of 35-85years [(62.5±12.9)years]. According to AO/OTA fracture classification system, there were 7 patients with type B and 37 with type C. Open reduction and internal fixation with volar plate was used in all patients, among which 22 were operated on using arthroscopy assistance (arthroscopy group) and 22 were operated on with traditional intraoperative fluoroscopy (fluoroscopy group). The operation time in both groups and triangular fibrocartilage complex (TFCC) injury and fracture displacement in arthroscopy group were recorded. Patient-rated wrist evaluation (PRWE) score, disabilities of the arm, shoulder and hand (DASH) questionnaire and range of wrist motion were compared between the two groups at 12 months after operation. The incidence of complications was observed.Results:All patients were followed up for 12-15 months [(13.3±1.1)months]. The operation time in arthroscopy group was (104.0±40.5)minutes, longer than (71.3±32.1)minutes in fluoroscopy group ( P<0.05). In arthroscopy group, 14 patients (64%) with TFCC injury were diagnosed intraoperatively, with the fracture displacement gap and step for 0.8 (0.3, 0.8)mm and 1.0 (0.3, 1.5)mm under arthroscopic vision, which were reduced to 0.3 (0.0, 0.5)mm and 0.5 (0.0, 0.5)mm after arthroscopically-assisted reduction (all P<0.05). The PRWE score in arthroscopy group was (9.8±4.9)points at 12 months after operation, lower than (13.4±5.8)points in fluoroscopy group ( P<0.05). The DASH questionnaire in arthroscopy group was (9.0±5.0)points at 12 months after operation, lower than (13.0±6.1)points in fluoroscopy group ( P<0.05). The dorsal extension and posterior rotation of the wrist in arthroscopy group were (73.8±8.9)° and (82.5±8.0)°, higher than (65.8±14.2)° and (76.3±10.4)° in fluoroscopy group (all P<0.05). There were no postoperative complications such as loosened or broken screws, vascular nerve damage, incision infection or traumatic arthritis in both groups. Conclusion:Arthroscopic-assisted open reduction and internal fixation of intra-articular distal radius fracture can increase the accuracy of joint surface reduction, improve postoperative wrist function and confirm the diagnosis of TFCC injury during operation.