Objective To explore the clinical effect of occipital-cervical fusion and its impact on cervical curvature, and preliminarily study the causes of postoperative dysphagia. Methods The data of 24 patients who underwent occipito-cervical fusion in the Fourth People’s Hospital of Zigong between January 2014 and December 2018 were retrospectively analyzed, including 13 males and 11 females, aged 33-82 years, with an average age of (58.3±13.3) years. Among them, there were 14 cases of atlas fractures, 6 cases of atlantoaxial fractures, 1 case of intraspinal canal space-occupying lesion, 2 cases of chronic atlantoaxial dislocation with spinal cord compression, and 1 case of instability caused by inflammatory diseases. Japanese Orthopedic Association (JOA) score and Visual Analogue Scale (VAS) score were used to evaluate neurological function and pain of patients preoperatively and postoperatively. Occipito-cervical angle (O-C2) and lower cervical angle (C2-C7) were measured to evaluate the preoperative and postoperative angle changes in patients. The causes of postoperative dysphagia were analyzed. Results All the 24 patients were followed up for 8-50 months (26.3 months on average). The mean JOA score increased from 11.6±1.5 before surgery to 15.4±1.2 at the last follow-up, and the mean VAS score decreased from 6.4±1.1 before surgery to 2.0±0.6 at the last follow-up; the differences between the two time points were statistically significant (P<0.001). The bone graft fusion rate was 95.8% (23/24). The mean O-C2 angle decreased from (16.5±7.6)° before surgery to (14.7±4.5)° at the last follow-up, with no statistical significance (P=0.395). The mean angle of C2-C7 increased from (9.4±5.5)° before surgery to (16.3±3.5)° at the last follow-up, and the difference was statistically significant (P<0.001). Two patients developed postoperative dysphagia, possibly due to fusion in a flexion position. Conclusion Occipito-cervical fusion has reliable efficacy in treating occipito-cervical instability, with a high fusion rate and a low incidence of complications, but it will change the physiological curvature of upper and lower cervical vertebra, and fusion in a flexion position may cause postoperative dysphagia.
ObjectiveTo explore the feasibility of the clinical application of individualized simulated S1 pedicle screw.MethodsThe data of patients with lumbar disease diagnosed and treated in the Fourth People’s Hospital of Zigong from May 2017 to April 2019 were retrospectively analyzed. According to the preoperative individualized design of the S1 pedicle screw placement path, the patients were divided into individualized screw placement group and traditional screw placement group. The distance D between the screw tip and the endplate of the S1, the angle α of the screw in the plane of the dysplasia and the lumbar pedicle of the L5, the angle of oblique angle β, the number of screws of 35 and 40 mm in length, and the screw loosening rate (followed-up within 1 year) in the two groups were analyzed.ResultsA total of 59 patients were enrolled in this study, 31 in the individualized screw placement group and 28 in the traditional screw placement group. The differences in the distance D between the screw tip and the endplate of the S1 [(2.61±0.82) vs.(4.13±1.51) mm; t=-5.718, P<0.001], the angle α of the screw in the plane of the dysplasia and the lumbar pedicle of the L5 [(9.31±3.52) vs. (13.53±4.78)°; t=-5.646, P<0.001], the angle of oblique angle β [(15.73±6.04) vs. (10.65±5.09)°; t=3.022, P=0.004], the proportion of using screw models [40 mm in length: 56 vs. 8; 35 mm in length: 6 vs. 48; χ2=68.539, P<0.001], and the screw loosening rate followed-up within 1 year [3.22% vs. 16.07%; χ2=5.774, P<0.001] were statistically significant between the individualized screw placement group and the traditional screw placement group.ConclusionsPreoperative individualized design of the pedicle screw of the S1 pedicle screw can be used in clinical practice. The biomechanical stability of the S1 pedicle screw can be improved and the sagittal balance can be achieved.