Spine Institute of Louisiana, 1500 Line Ave., Ste 200, Shreveport, LA 71115, USA.
Spine J. 2013 Jan;13(1):5-12. doi: 10.1016/j.spinee.2012.11.032. Epub 2013 Jan 11.
Although several publications in the last decade have proved equality in safety and efficacy of the total disc replacement (TDR) to the anterior fusion procedure in cervical spine, the claim that TDR may reduce the incidence of adjacent segment disease (ASD) has not been corroborated by clinical evidence.
We attempt to predict the true incidence of symptomatic ASD after TDR surgery in the cervical spine at one or two levels at a median follow-up period of 4 years.
A total of 763 patients were screened to participate in four different Food and Drug Administration device exemption trials for artificial cervical disc replacement at three collaborating institutions. Two hundred seventy-one patients qualified and enrolled in the trials. One hundred seventy-three randomized to receive artificial disc replacement surgery, and 167 have completed a 4-year or longer follow-up.
Patients experiencing cervical radiculopathy symptoms in the follow-up period were worked-up with clinical examinations, magnetic resonance imaging of the cervical spine, and other diagnostic studies. Once a clinical correlation was established with the imaging evidence of adjacent segment degeneration, a careful record was maintained to document the subsequent medical and/or surgical treatment received by these patients. Statistical analysis was performed to determine the true incidence of and factors affecting the ASD after cervical disc replacement in these patients.
Twenty-six patients (15.2%) were identified to satisfy our criteria for ASD at the median follow-up of 51 months, with the annual incidence of 3.1% as calculated by life tables. The actuarial 5-year freedom from ASD rate was 71.6%±0.6%, and the mean period for freedom from ASD was 70.4±2.1 months.
The incidence of symptomatic ASD after cervical TDR is 3.1% annually regardless of the patient's age, sex, smoking habits, and design of the TDR device. The presence of osteopenia and lumbar degenerative disease significantly increase the risk of developing ASD after anterior cervical surgery.
尽管过去十年的几项研究已经证明，在颈椎中，全椎间盘置换术（TDR）与前路融合术在安全性和疗效方面具有同等地位，但 TDR 可能降低邻近节段疾病（ASD）发生率的说法尚未得到临床证据的证实。
我们试图预测在颈椎中进行 TDR 手术后，在中位数为 4 年的随访期内，一个或两个节段发生有症状的 ASD 的真实发生率。
共有 763 名患者被筛选参加了在三个合作机构进行的人工颈椎间盘置换术的四项不同的食品和药物管理局设备豁免试验。271 名患者符合条件并参加了这些试验。其中 173 名随机接受人工椎间盘置换手术，167 名完成了 4 年或更长时间的随访。
在随访期间出现颈椎神经根病症状的患者接受了临床检查、颈椎磁共振成像和其他诊断研究。一旦与邻近节段退变的影像学证据建立临床相关性，就会仔细记录这些患者随后接受的医疗和/或手术治疗。进行了统计分析，以确定这些患者颈椎间盘置换术后 ASD 的真实发生率和影响因素。
在中位数为 51 个月的随访中，有 26 名患者（15.2%）符合我们的 ASD 标准，通过寿命表计算，每年的发病率为 3.1%。5 年无 ASD 的累积生存率为 71.6%±0.6%，无 ASD 的平均时间为 70.4±2.1 个月。
无论患者的年龄、性别、吸烟习惯和 TDR 装置的设计如何，颈椎 TDR 后发生有症状的 ASD 的发生率为每年 3.1%。骨质疏松症和腰椎退行性疾病的存在显著增加了颈椎前路手术后发生 ASD 的风险。
