Neuro- and Spine Centre, Hirslanden Clinic St. Anna, St. Anna Strasse 32, 6006, Lucerne, Switzerland.
Acta Neurochir (Wien). 2013 Oct;155(10):1923-30. doi: 10.1007/s00701-013-1774-1. Epub 2013 Jun 8.
The objective of this study was to correlate various radiological parameters with clinical outcome in patients who had undergone lumbar total disc replacement (TDR). Lumbar TDR is one possible treatment option in patients with low back pain (LBP), offering an alternative to lumbar fusion. Favourable clinical outcome hinges on a number of radiological parameters, such as mobility, sintering, and-most importantly-accurate positioning of the implant.
A total of 46 patients received a prosthetic disc because of degenerative lumbar disc disorders. Follow-up evaluation included analysis of radiographs and subjective rating of the clinical status by the patient using the North American Spine Society (NASS) patient questionnaire, visual analogue scale (VAS) for pain and state of health, and the EuroQol EQ-5D. Radiological follow-up took place after 2 years. Coronal and sagittal positions of the prosthesis, intervertebral disc height, facet joint pressure, mobility, sintering, and calcification were evaluated. Optimal positioning of the prosthesis was defined as a central coronal position and a most dorsal position in the sagittal plane. Based on the radiologically determined placement of the prosthesis, the patient population was divided into three groups, i.e., prosthesis ideally placed (<2 mm), discretely shifted (2-3 mm), or suboptimally placed (>3 mm).
Overall, 81 % of patients stated that they would undergo the operation again. Health status was stable at a VAS score of 7.04 points 2 years after TDR, compared to 3.97 points before TDR. Mean working capacity had increased from 53 % preoperatively to 88 % 2 years after TDR. Overall, 39 % of the prostheses were rated as ideally positioned, while 13 % were discretely shifted and 48 % were suboptimally placed with respect to one of the radiological criteria. In 80.4 % of patients, follow-up assessment after ≥2 years indicated good mobility at the operated segment, while calcification was noted in 4 % and sintering was detected in 15 % of the implants.
Our data indicate poor correlation between clinical outcome and position of the prosthesis. Although 48 % of the implants were suboptimally placed in either the coronal or sagittal plane, most of the patients reached a very good clinical outcome. However, suboptimally placed devices appeared to cause significantly more neurological symptoms in long-term follow-up.
本研究旨在探讨腰椎全椎间盘置换（TDR）患者的各种影像学参数与临床结果的相关性。腰椎 TDR 是腰痛（LBP）患者的一种可能的治疗选择，可替代腰椎融合术。良好的临床结果取决于许多影像学参数，如活动度、烧结和最重要的是植入物的准确定位。
共有 46 例患者因退行性腰椎间盘疾病接受了人工椎间盘。随访评估包括分析 X 线片和患者使用北美脊柱协会（NASS）患者问卷、疼痛和健康状况的视觉模拟量表（VAS）以及 EuroQol EQ-5D 对临床状况的主观评分。术后 2 年进行影像学随访。评估假体的冠状和矢状位置、椎间盘高度、小关节压力、活动度、烧结和钙化。假体的最佳定位定义为冠状面中央位置和矢状面最背侧位置。根据影像学确定的假体位置，将患者分为三组，即假体理想位置（<2mm）、明显移位（2-3mm）或位置不佳（>3mm）。
总体而言，81%的患者表示愿意再次接受手术。与 TDR 前的 3.97 分相比，TDR 后 2 年的健康状况稳定在 VAS 评分 7.04 分。术后 2 年，患者的平均工作能力从术前的 53%增加到 88%。总体而言，39%的假体被评为理想位置，13%的假体明显移位，48%的假体在一个影像学标准上位置不佳。在 80.4%的患者中，≥2 年的随访评估表明手术节段活动良好，而 4%的患者出现钙化，15%的患者出现烧结。
我们的数据表明临床结果与假体位置之间相关性较差。尽管 48%的植入物在冠状面或矢状面位置不佳，但大多数患者获得了非常好的临床结果。然而，在长期随访中，位置不佳的设备似乎会导致更多的神经症状。
