BACKGROUND:Atlantoaxial dislocation,because of its high difficulty and high risk of surgery,has been regarded as the"surgical restricted area"by the international orthopedic community.However,with the rapid development of intelligent digitization in orthopedics,robot-assisted navigation screw placement technology has been widely used in clinical practice,which significantly reduces the difficulty and risk of surgery and improves the safety of surgery.However,there are few reports on the application of this technique in the treatment of atlantoaxial dislocation. OBJECTIVE:To explore the application value of robot-assisted pedicle screw internal fixation in the treatment of atlantoaxial dislocation. METHODS:The medical records of five patients with atlantoaxial dislocation treated with C1-C2 pedicle screw fixation under robot-assisted navigation in Zhuhai Hospital of Guangdong Provincial Hospital of Chinese Medicine from October 2021 to July 2022 were retrospectively analyzed.Operation time,length of neck incision,blood loss,postoperative drainage volume,and length of hospital stay were recorded.Attention should be paid to cerebrospinal fluid leakage,vertebral artery injury,nerve injury,operative area infection and other complications.The visual analog scale score of neck pain,the spinal cord injury grade of the American Spinal Injury Association,the cervical spine score of the Japanese Orthopaedic Association,and the imaging indicators were collected before surgery and at the last follow-up.Screw placement accuracy was assessed. RESULTS AND CONCLUSION:(1)Five patients were successfully completed surgery,without vascular,nerve injury or other complications,and were followed up for 12-20 months.(2)A total of 20 cervical pedicle screws were placed in 5 patients,including 9 type A screws,10 type B screws,and 1 type C screw.The accuracy of screw placement was 95%.(3)At the last follow-up,the visual analog scale score was(0.80±0.71)points,which was significantly lower than that before operation(4.00±2.83)points;the Japanese Orthopaedic Association score was(14.80±0.84)points,which was significantly higher than that before operation(8.00±0.71)points.Anterior atlantodental interval decreased from(7.86±3.25)mm to(2.82±0.93)mm;space available of the spinal cord increased from(6.74±1.99)mm to(12.10±3.51)mm;cervicomedullary angle increased from(133.32±13.55)° to(153.44±9.53)°;clivus-canal angle increased from(128.02±9.92)° to(143.25±12.99)°.The results of the last follow-up indexes were improved compared with those before operation,and the differences were significant(all P<0.05).(4)Postoperative imaging follow-up showed that all patients had bone fusion in the bone graft area,and no internal fixation loosening,fracture or pull-out occurred.(5)This method can avoid relying on the doctor's experience and hand feeling,ensure the accuracy of upper cervical screw placement,reduce the risk of surgery,and obtain satisfactory results in mid-term follow-up.