Comparison Of Cervical Total Disk Replacement Versus Anterior Cervical Fusion For Two-level Cervical Spondylosis

Objective:To compare the clinical outcome of cervical total disc replacement(cTDR)with that of anterior decompression and fusion(ACDF)in patients with 2 contiguous levels cervical spondylosis.Methods:Our study includes 46 patients who suffered symptomatic cervical spondylosis underwent cervical total disc replacement(cTDR group,17 cases)and anterior decompression and fusion(ACDF group,29 cases)in Qilu hospital from July 2013 to July 2015.The average time that the patients in both groups were followed up was 24 months.The Japanese Orthopaedic Association(JOA)score,neck disability index(NDI)and limb visual analogue scale(VAS)were used to evaluate the clinical outcomes at 6 time points,including preoperatively and 7days.3.6.12.24 months postoperatively.While the ROM.IROM.SROM and adjacent segment degeneration were vauled preoperatively and 7days.3.6.12,24 months postoperatively by X-rays.Results:The evaluation of perioperative and complication:there is no significant variation between cTDR group and ACDF group(P>0.05).The evaluation of clinical efficacy:the clinical indicators including JOA,NDI and VAS of two groups compared between before and after the surgery,the difference was statistically significant(P<0.05).Comparison between the two groups:The JOA score of cTDR group was significantly higher than that of ACDF group at 3 months postoperative(P<0.01).The NDI of cTDR group was significantly lower than that of ACDF group at 3,6,12,24 months postoperative(P<0.01).And there is no significant variation between the two groups in the rest of the clinical indicators(P>0.05).The evaluation of radiological evidence:Compared the pre-and postoperative ROM of C2-7,superior and inferior levels of each group respectively,the difference between preoperative ROM and postoperative ROM of ACDF group was statistically significant(P<0.001),while was no statistically significant of cTDR group(P>0.05).And there is no significant variation between the two groups in the evaluation of adjacent segment degeneration(P>0.05).Conclusions:Cervical total disc replacement and anterior cervical discectomy and fusion are effective treatments for 2 contiguous levels cervical spondylosis.and there is no significant difference in adjacent segment degeneration between two groups.But,comparing to ACDF,cTDR could provide a better clinical effects in the middle or short term and has the ability to maintain the ROM of the operation segments and cervical spine.And cTDR don’t increase the mobility of adjacent segments.