The Effect Of Center Gravity Of Head's Reset On Lower Cervical Degeneration After Occipitocervical Fusion

Object:To observe the effect of center gravity of head's reset on cervical degeneration after occipitocervical fusion.Methods:A retrospective analysis of 83 patients admitted to the Spinal Cord Center of Henan Provincial People's Hospital from September 2012 to December 2016.All these patients underwent posterior decompression and occipitocervical fusion surgery for atlantoaxial dislocation due to occipitocervical malformation.Among them,8 cases were treated with orogastric resolving and decompression through the anterior approach.Each patient were measured the position of the center gravity of head and C2-7 cobb angle before,during and after the last follow-up.Record VAS,JOA,and NDI scores at preoperative,postoperative,and final follow-up for each patient.Statistical analysis of general data such as gender,age,preoperative VAS,JOA,and NDI scores for each group.According to whether the center gravity of head was reset or not after the operation,it was divided into two groups(group a and b).Comparative analysis the change of center gravity of head and C2-7 cobb angle before and after surgery and analyze their relevance.Results:There was no significant difference in general data such as age and gender distribution among groups of patients(P>0.05).There was no significant difference in preoperative VAS,JOA,and NDI functional scores between groups of patients(P>0.05).JOA,VAS,and NDI scores improved significantly after surgery in all patients(P < 0.05).There was a significant difference in the C2-7 cobb angle between postoperative and final follow-up in each group(P<0.05).The difference in C2-7cobb angle between the postoperative and the last follow-up in the reduction group was significantly smaller than that in the non-reset group.Negative linear correlation between CGH-C7 SVA and C2-7 cobb angle in preoperative patients,Negative linear relationship between C2-7 cobb angle and CGH-C7 SVA at the last follow-up.Conclusion:The restoration of the center gravity of head can be used as an index to evaluate the surgical treatment of occipitocervical malformation and the degree of postoperative cervical degeneration.During occipitocervical fusion surgery,try to restore the physiological position of the center gravity of head,but it should also avoid over-resetting the center gravity of head.