The Experimental Study On The Oblique Design Of The Tail End Of The Titanium Mesh Cage To Prevent The Sinking Of The Titanium Mesh Cage After ACCF

Background and purposeTitanium mesh cage(TMC)is one of the fusion devices used in anterior cervical corpectomy and fusion(ACCF).It can not only immediately rebuild the stability of cervical spine during the operation,maintain the height and physiological curvature of intervertebral vertebrae,but also avoid the complications of bone donor area caused by autologous bone extraction.Therefore,titanium mesh cage has become the most commonly used internal plant in ACCF.But traditional titanium mesh cages still have some drawbacks,the titanium mesh cages currently used in ACCF surgery are mostly hollow cylinders with a circular horizontal surface at the end,however,the upper endplate of the cervical vertebra has a slope.After the titanium mesh cage is implanted into the intervertebral body,the tail end of the titanium mesh cage cannot fully fit with the upper endplate,instead,a point-to-surface contact is formed,which will cause stress concentration at the contact part and cause the titanium mesh cage to subsidence.And in order to match the decompression groove,the surgeon often needs to trim the titanium mesh cage,resulting in the formation of sharp protrusions at the end of the titanium mesh cage,which makes it easier to penetrate into the endplate.The severe subsidence of the titanium mesh cage can lead to various postoperative complications,such as postoperative loss of intervertebral height and physiological curvature,re-shrinkage of the spinal cord and nerve roots,resulting in recurrence of neurological symptoms and failure of internal fixation.The purpose of this research is to improve the traditional titanium mesh cage by trimming the tail end of the titanium mesh cage into an inclined plane so that the tail end of the titanium mesh cage fits the upper endplate of the cervical vertebra as much as possible,and by comparing the biomechanical test of the titanium mesh cage with the oblique design of the tail end and the traditional titanium mesh cage,the effect of the improved titanium mesh cage in preventing the subsidence of the titanium mesh cage is evaluated.MethodsAccording to the standard of YY/T 0960-2014 spinal implant interbody fusion cage static axial compression and subsidence test method,the endplate supportive load of the tail-end oblique design titanium mesh cage and the traditional titanium mesh cage were tested respectively,and the data results were analyzed.This evaluation improves the effectiveness of the titanium mesh cage in preventing subsidence of the titanium mesh cage.ResultsThe maximum load of the titanium mesh cage with oblique tail end design is(851.5±4.8 N),which is significantly higher than the maximum load of the traditional titanium mesh cage(704.8±4.7 N),and the difference is statistically significant(P<0.05).Conclusions1.The oblique design of the tail end of the titanium cage can better fit the upper endplate of the lower vertebral body of the surgical segment and increase the contact area.2.The oblique design of the titanium cage at the tail end can significantly improve the support strength of the end plate,thereby effectively reducing the possibility of sinking of the titanium cage.