Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital, Beitou, Taipei 11217, Taiwan.
J Neurosurg Spine. 2012 Feb;16(2):163-71. doi: 10.3171/2011.10.SPINE11497. Epub 2011 Dec 2.
Cervical arthroplasty is a valid option for patients with single-level symptomatic cervical disc diseases causing neural tissue compression, but postoperative heterotopic ossification (HO) can limit the mobility of an artificial disc. In the present study the authors used CT scanning to assess HO formation, and they investigated differences in radiological and clinical outcomes in patients with either a soft-disc herniation or spondylosis who underwent cervical arthroplasty.
Medical records, radiographs, and clinical evaluations of consecutive patients who underwent single-level cervical arthroplasty were reviewed. Arthroplasty was performed using the Bryan disc. The patients were divided into a soft-disc herniation group and a spondylosis group. Clinical outcomes were measured using the visual analog scale (VAS) for neck and arm pain and the Neck Disability Index (NDI), whereas HO grading was determined by studying CT scans. Radiological and clinical outcomes were analyzed, and the minimum follow-up duration was 24 months.
Forty-seven consecutive patients underwent a single-level cervical arthroplasty. Forty patients (85.1%) had complete radiological evaluations and clinical follow-up of more than 2 years. Patients were divided into 1 of 2 groups: soft-disc herniation (16 cases) and the spondylosis group (24 cases). Their mean age was 45.51 ± 11.12 years. Sixteen patients (40%) were female. Patients in the soft-disc herniation group were younger than those in the spondylosis group, but the difference was not statistically significant (42.88 vs 47.26, p = 0.227). The mean follow-up duration was 38.83 ± 9.74 months. Sex, estimated blood loss, implant size, and perioperative NSAID prescription were not significantly different between the groups (p = 0.792, 0.267, 0.581, and 1.000, respectively). The soft-disc herniation group had significantly less HO formation than the spondylosis group (1 HO [6.25%] vs 14 Hos [58.33%], p = 0.001). Almost all artificial discs in both groups remained mobile (100% and 95.8%, p = 0.408). The clinical outcomes were not significantly different between the groups at all postoperative time points of evaluation, and clinical improvements were also similar.
Clinical outcomes of single-level cervical arthroplasty for soft-disc herniation and spondylosis were similar 3 years after surgery. There was a significantly higher rate of HO formation in patients with spondylosis than in those with a soft-disc herniation. The mobility of the artificial disc is maintained, but the long-term effects of HO and its higher frequency in spondylotic cases warrant further investigation.
颈椎置换术是治疗单节段因神经组织受压而导致症状性颈椎间盘疾病的有效方法，但术后异位骨化（HO）可能会限制人工椎间盘的活动度。在本研究中，作者使用 CT 扫描评估 HO 形成，并研究了行颈椎置换术的椎间盘突出症或颈椎病患者在影像学和临床结果方面的差异。
回顾性分析了连续接受单节段颈椎置换术的患者的病历、影像学资料和临床评估资料。使用 Bryan 椎间盘进行置换术。患者分为椎间盘突出症组和颈椎病组。采用视觉模拟量表（VAS）评估颈痛和臂痛以及 Neck Disability Index（NDI）评估颈椎功能障碍，通过 CT 扫描评估 HO 分级。分析影像学和临床结果，随访时间至少 24 个月。
47 例连续患者接受了单节段颈椎置换术。40 例（85.1%）患者完成了完整的影像学评估和超过 2 年的临床随访。患者分为 2 组：椎间盘突出症组（16 例）和颈椎病组（24 例）。他们的平均年龄为 45.51±11.12 岁。16 例（40%）为女性。椎间盘突出症组患者的年龄小于颈椎病组，但差异无统计学意义（42.88 岁 vs 47.26 岁，p=0.227）。平均随访时间为 38.83±9.74 个月。性别、估计失血量、植入物大小和围手术期 NSAID 处方在两组间差异均无统计学意义（p=0.792、0.267、0.581 和 1.000）。椎间盘突出症组的 HO 形成明显少于颈椎病组（1 例[6.25%] vs 14 例[58.33%]，p=0.001）。两组所有人工椎间盘均保持活动度（100%和 95.8%，p=0.408）。两组在术后所有评估时间点的临床结果均无显著差异，临床改善情况也相似。
3 年后，颈椎置换术治疗椎间盘突出症和颈椎病的临床效果相似。颈椎病患者的 HO 发生率明显高于椎间盘突出症患者。人工椎间盘的活动度得以维持，但 HO 的长期影响及其在颈椎病患者中的高发生率需要进一步研究。
