Study of nerve root traction injury in lumbar interbody fusion from posterior rout approach / 中国矫形外科杂志

ABSTRACT

[Objective]To discuss incidence of nerve root stretch injury and threshold value of traction injury in lumbar interbody fusion from posterior rout approach. [Method]Totally patients were treated by lumbar interbody fusion performed with posterior approach using the safe nerve root retractor,the force of dragging nerve root and the retracting time were showed on the display device,while the latency and amplitude of the DSEP wave were measured with Keypoint to monitor the status of the neural function.JOA scores were followed up 10 days,1 month,3 months and 12 months after operation respectively.[Result]Nineteen cases occurred latency prolongation and wave amplitude digression during the operation,when the tensile strength to nerve root was(4.1? 0.45) N and accumulating strength was(42.89?2.96) N*min.The tensile force of aggravation groups exceed stable and improvement groups obviously,incidence of FBSS was higher than the other two groups.[Conclusion]Stretch injury of nerve root during operation is the main cause of earlier period FBSS after interbody fusion.Master single tensile force less than(4.1? 0.45) N or accumulating strength less than(42.89?2.96) N*min is presumed safety.