基于X线片猫眼分区评估腰椎椎弓根螺钉徒手置钉安全性的影像学研究OA

Objective To investigate the safety of manual lumbar pedicle screw placement based on the position of the cat's eye(pedicle projection)on X-ray films.Methods A total of 150 patients with lumbar spine disorders from December 2022 to June 2024 were enrolled and classified into three types according to the cat's eye position on AP X-rays:type A(the lateral edge of the cat's eye extends beyond the lateral edge of the vertebral body);type B(the lateral edge of the cat's eye largely coincides with the lateral edge of the vertebral body);and type C(the lateral shadow of the pedicle is located at the me-dial edge of the pedicle).Patients were divided into two groups:the imaging-guided simulation group(90 patients,30 each in types A,B,and C)and the imaging review group(60 patients,20 each in types A,B,and C).All patients underwent screw in-sertion at the intersection of the inferior third of the transverse process and the lateral edge of the articular process.In the imag-ing-guided simulation group,the lumbar spine was divided into three regions from medial to lateral on AP X-rays;the screw di-rection was adjusted so that the tip of the screw tract corresponded to these three regions on the virtual projection,and CT anal-ysis was performed to evaluate accuracy and determine whether the medial wall of the pedicle or the lateral edge of the verte-bral body was penetrated.The imaging review group included 60 patients with lumbar pedicle screw placements;their AP and lateral X-ray images as well as postoperative CT data were analyzed to quantify the number of screws at corresponding positions and assess effectiveness via postoperative CT evaluation.Results In the imaging-guided simulation study,the rate of successful screw placement in zone 3 for type A patients was 96.67％(29/30),significantly higher than that in zone 1 50％(15/30)and zone 2 86.67％(26/30),with a statistically significant difference(P＜0.05);In type B cat's eyes,the placement rates of screws in zone 1 and zone 2 were 90.00％(27/30)and 93.33％(28/30),respectively,significantly higher than those in zone 3 70％(21/30),with a statistically significant difference(P＜0.05);In type C cat's eyes,the placement rate in zone 1 was 90.00％(27/30),superior to that in zone 2 63.33％(19/30)and zone 3 40％(12/30),also showing a statistically significant difference(P＜0.05).Imaging analysis revealed that among patients with type A cats eyes,screw placements were in zone 1(3 cases),zone 2(10 cases),and zone 3(7 cases);the placement rates in zones 2 and 3 were 90％(9/10)and 100％(7/7),respec-tively,significantly higher than that in zone 1 33.3％(1/3),with a statistically significant difference(P＜0.05).For patients with type B cat's eyes,the placement rates in zones 1 and 2 were both 100％(5/5)and 100％(12/12),significantly higher than that in zone 3 33.3％(1/3),with a statistically significant difference(P＜0.05).In patients with type C cat's eyes,the placement rate in zone 1 was 100％(10/10),significantly higher than that in zones 2 and 3 87.5％(7/8)and 0％(0/2),re-spectively,with a statistically significant difference(P＜0.05).Conclusion By analyzing the relative positions of the cat's eye and vertebral body on anteroposterior X-rays,this study establishes a quantitative correlation between cat's eye zones and screw placement areas for the first time,effectively preventing spinal cord injury and reducing surgical risks.