Efficacy Of Posterior Cervical Laminoplasty Using Absorbable Anchors In Treatment Of Multi-segment Cervical Spondylotic Myelopathy

Objective:In this article,we aimed to evaluate the safety and effectiveness of the application of absorbable anchors in posterior cervical laminoplasty to treat multi-segment cervical spondylotic myelopathy.Methods:We performed a prospective study of 52 consecutive patients undergoing posterior cervical open-door laminoplasty.All 52 patients were divided into two groups according to the type of implants used in surgery: experimental group(the absorbable anchors group),including 22 patients,16 males and 6 females,mean age of 58.6 ± 2.6(34-80)years;control group(the metal anchors group),including 30 patients,21 males and 9 females,mean age of 56.0 ± 1.8(39-79)years.The operation time,intraoperative blood loss,postoperative drainage,duration of hospital stay,and complications were recorded.Clinical outcomes were evaluated by pre-and post-operative Japanese Orthopedic Association(JOA)score and visual analog scale(VAS)neck pain.Patients were followed up by outpatient review or telephone follow-up.The average follow-up time was 20 months(range 9–34 months).Statistical significance of the data was evaluated using 2-sample t-test or Chi-square test.A P value of <0.05 was considered significant.Results:All the patients achieved satisfactory clinical outcome.However,no significant difference was found in VAS and JOA scores between both groups during the follow-up periods.And There was no significant difference in the rate of C5 palsy between two groups(1/22 vs.2/30,P > 0.05).Other complications such as dural tears,infection,hardware failure,kypothic deformity and secondary closure of the opened doors were not observed in both of the two groups.Though there was no significant difference in operation time,intraoperative blood loss or postoperative drainage between the two groups,the duration of hospital stay in experimental group was a little longer than that in control group(16.0 vs.13.7,P<0.05).Conclusions:In posterior cervical laminoplasty,the absorbable anchors are at least as safe and efficacious as the metal anchors.The absorbable anchors have the advantage of not interfering with radiological examinations and do not increase the incidence of complications in posterior cervical laminoplasty.Thus,we recommend this type of implants for application in cervical laminoplasty for the treatment of multi-segment cervical spondylotic myolapathy.