Compare Between The Dynamic Anterior Cervical Plate System Versus The Rigid Anterior Cervical Plate System On The Effect On The Rate Of Cervical Curvature Loss And Graft Settling In The Anterior Cervical Discectomy And Fusion

Subject:Anterior cervical plate fixation:To compare clinical Results,the cervical curvature loss and graft sellting between the dynamic anterior cervical plate versus the rigid anterior cervical plate in the anterior cervical discectomy and fusion(ACDF)treatment of short segment ancervical spondylosis.Methods:Seventy-six multilevel cervical spondylosis patients including 43 males and 33 females with the age from 45-76 years old(average 54-year-old)treat with anterior cervical discectomy and fusion(ACDF)in our department from March 2014 to February 2015 were recruited.They were divided into two groups,in which rigid anterior cervical plates consisted 22 cases of signal-level and 14 cases of two-level and dynamic anterior cervical plates consisted 25 cases of signal-level and 15 cases of two-level.The data about cervical spine radiographies in pre-operation,one month,six months,one year after the operation and JOA score Intervertebral height and Intervertebral curvature of all patients were gathered and analyzed by paired T test within group and chi-square test between groups with SPSS19.0 software and P <0.05 was defined as statistically significant.Result:All patients were complete follow-up data up for 12-20 months with an average of 14 months.Two groups of patients after surgery have all received bone fusion(fusion rate was 100%).Dynamic plate group compared with rigid plate group has a faster fusion rate(after 6 months dynamic plate group 55% of patients bonefusion),while rigid plate group only 39% of patients with bone fusion.No patient experienced broken nails,steel shifted,interbody fusion cage slip or other serious complications.Two groups of patients after surgery nerve function(JOA score)were significantly improved compared with preoperative((P <0.05),between the two groups JOA score was no significant difference.Rigid anterior cervical plate group from preoperative JOA score(10.3 ± 1.9)points up to(14.2 ± 1.3)points,dynamic anterior cervical plate group increased from(10.5 ± 1.4)points up to to(14.5 ± 1.0).The fusion segment curvature compared two groups of patients were significant(P <0.05),The rate of fusion segment curvature loss was(0.4±1.4)°in signal level patients and(0.6±1.3)°in two level patients in a year after the operation in rigid anterior cervical plate group.In dynamic anterior cervical plate group,the rate was(1.1±1.0)°and(1.5±2.5),respectively.Data between the two groups were significantly different at postoperative 6 months and1 year(P <0.05),dynamic plate has a loss of fusion segments curvature than rigid plate.Fusion segments height of the two groups of patients than before surgery improved(P <0.05),The amount of Interbody fusion segments height loss was(0.4±0.8)mm in signal level patients and(0.7±1.2)mm in two level patients in a year after the operation in rigid anterior cervical plate group.In dynamic anterior cervical plate group,the amount was(1.4±1.2)mm and(2.4±1.4)mm,respectively.Data between the two groups were significantly different at Postoperative 6 months and 1year(P <0.05),dynamic plate has a loss of fusion segments height than rigid plate.Conclusions: 1.Meaningful clinical result could be obtain with the application of either rigid anterior cervical plate or dynamic anterior cervical plate in the anterior cervical discectomy and fusion(ACDF)treatment of short segment ancervical spondylosis.2.The dynamicrigid anterior cervical plate had advantages over the rigid anterior cervical plate in faster bone fusion while has more rate of cervical curvature loss and graft settling.