研究方法：影像学及临床症状随访研究

研究目的：评价颈椎人工间盘置换术对颈椎小关节退变影响，及术前不同程度退变小关节对人工间盘置换术后颈椎节段运动和患者临床症状缓解程度的影响。

材料和方法：选择没有明显小关节退变的颈椎病患者（神经根型或脊髓型）行单节段或双节段Bryan颈椎人工间盘置换术，并进行4年临床随访。术前及随访影像学评估包括通过颈椎动力位X光片测量颈椎节段屈伸活动度，和通过计算机断层扫描（CT)及影像学重建评价颈椎小关节退变程度，临床症状评估在术前及末次随访同时进行。

结果：术前28例患者下颈椎各小关节未发现明显退变，归类为小关节无或轻度退变组，9例存在手术节段或邻近节段小关节中度退变，并归为小关节中度退变组。末次随访，所有患者颈椎小关节退变影像评估较术前无变化。手术节段活动度得到保留，但是小关节中度退变组在末次随访时发现更多失去活动的人工间盘，并且发现这组患者手术邻近节段活动度大于小关节无或轻度退变组，可是统计学差异并不显著。随访中患者临床症状均明显缓解，没有发现临床症状与小关节退变关系。

结论：颈椎人工间盘置换术延缓了颈椎小关节退变，这可能归因于人工间盘很好地保留了颈椎生物力学功能，同时，不同程度的小关节退变影响了颈椎节段活动度，但是未发现与临床症状之间的联系。

STUDY DESIGN: Radiographic and clinical assessment following cervical arthroplasty.

OBJECTIVE: To investigate the incidence of cervical facet degeneration following arthroplasty and the influence of different grades of facet degeneration on segmental range of motion(ROM)and clinical outcome.

MATERIALSAND METHODS: Patients without significant facet degeneration underwent single or bi-level implantation of the Bryan artificial cervical disc for treatment of cervical spondylosis. Dynamic radiographs and computed tomography (CT) were performed to measure ROM and assess the facet degeneration according to a modified quantitative scoring system before surgery and at intervals up to 4 years after surgery. Clinical outcomes were also evaluated pre- and postoperatively.

RESULTS：Preoperatively 28 and 9 patients were categorized to the none-mild and moderate facts degeneration group respectively. At late follow-up, development of facet degeneration was not found in all of the patients. Segmental ROM was preserved, but there was a tendency toward more immobile devices and more values of adjacent ROM with moderate facet degeneration than that in the none-mild facet degeneration group, even though the differences were not significant. Clinical evaluation was significant improvement both in the two groups, but the relationship between the grade of facet degeneration and clinical results was not concluded.

CONCLUSIONS：Cervical arthroplasty prevents facet joint from accelerating degeneration, which may contribute to the biomechanical advantage of prosthesis. Various grades of facet degeneration influence the index and adjacent segmental ROM, but were not associated with clinical outcomes in our study.