Assessment of Anterior Dynamic Cervical Implant in Surgery of Cervical Disc Degeneration

Abstract

Introduction: The optimal surgical intervention for spondylotic cervical myelo-radiculopathy of degenerative cervical disc disease is a subject of controversy.Anterior cervical discectomy and fusion (ACDF) is considered the gold standard treatment for of degenerative cervical disc disease, although it is highly effective at decompressing neural elements and stabilizing the spine, is accused of predisposing for adjacent-level degeneration. In the past years, there have been a large number of reports on advantages and disadvantages of cervical disc arthoplasty. Limitations for the use of prostheses are restricted indications, hypermobility, possible over-distraction and a number of other design specific complications Disc replacement with DCI is a new strategy, in between ACDF & TDR. It is an intermediate solution in the spectrum of management strategies of cervical disc diseases. On the contrary to TDR, The DCI implant offers stable, controlled (adequate) motion to already significantly degenerated motion segments. Aim of the work: To evaluate efficacy and safety of cervical arthroplasty (using dynamic cervical implant) in cervical degenerative disc diseases as regard preservation of cervical biomechanics to prevent adjacent segment degeneration. 238 Patients and methods: The present study included 27 cases of degenerative cervical disc disease of single or multiple levels, presenting with neck pain and radiculopathy and /or myelopathy .all patients were managed by anterior cervical discectomy and DCI implantation , with pre and post operative assessment both clinically and radiologically and functionally using visual analogue score (VAS), and neck disability index (NDI). Results: Mean age was 43+9, 20 males (74%) ,7 females (26%), single level 17(62%) , double level 9 (33%), triple levels 1(3.7%), the commonest level was C5-6 10 (37%), commonest implant size used was large 14 (52%). There was significant functional and clinical improvement (p value 0.000).VAS neck improved in 80% of cases with average change of 74%, VAS right arm improved in 90% with average change 95%, VAS left arm improved in 90% with average change 70%, NDI improved in 90% with average change 60% at the end of the study. Anterior migration occurred in 6 cases (22 %) and one case of subsidence (3.7%) There were no case of fusion after one year follow up except the four complicated cases that was managed with fixation. Discussion: In the present study it was found that usage of DCI in cervical degenerative disc disease results in adequate clinical improvement that lasted for the end of the study (one year follow up) with preservation of motion of treated level with no evidence of adjacent segment degeneration,however there were a significant rate of complications in the form of anterior migration and 239 subsidence, without catastrophic complications (no posterior migration) Conclusion: Treating cervical disc disease with the DCI™ implant is an efficient and easy procedure. Immediate dynamic stability with good clinical response and no serious implant-related morbidity, but further studies are needed to make sure of its safety and long term efficacy. Conflict of intrest: The authors confirm that this article content has no conflicts of interest. Key words: Cervical disc disease, degenerative cervical spine, ACDF, cervical arthroplasty, total cervical disc replacement, dynamic cervical implant, and cervical biomechanics.