Abstract: Objective：To compare the midterm therapeutic effect of dynamic cervical implant(DCI) and Prestige LP artificial cervical replacement for the treatment of cervical disc herniation.Methods：49 patients were included for cervical disc herniation and underwent surgery in our hospital.They were divided into DCI group(Group A) and Prestige LP group(Group B).The VAS,JOA,SF36 and Range of motion(ROM) were compared of the two groups.Results：There were 22 patients in Group A,with a mean followup time of 24.5 months.27 patients were included in Group B,with a mean followup time of 25.8 months.The VAS,JOA and SF36 of the two groups were no significant difference between the two groups(P＞0.05).The ROM of C27 of the two groups showed no significant difference(P＞0.05).The ROM of operated level was greater at last follow up than preoperation in Group B(P<0.05),and the ROM of operated level was greater in Group B than Group A at last follow up significantly(P<0.05).Conclusions：The clinical results in DCI were similar as Prestige LP artificial cervical replacement in earlymedium period.The semiconstrained feature of DCI may take protection for the facet joint of operated level to some extent and the indications was larger than cervical disc implantation.

Key words: cervical disc herniation, dynamic cervical implant, cervical disc replacement, nonfusion, range of motion