Barbagallo Giuseppe M V, Corbino Leonardo A M, Papavero Luca, Fritzsche Erik, Albanese Vincenzo
Department of Neurosurgery, Azienda Ospedaliero-Universitaria Policlinico G. Rodolico, Viale XX Settembre 45, 95129 Catania, Italy.
J Spinal Disord Tech. 2009 Dec;22(8):610-4. doi: 10.1097/BSD.0b013e31819b0a6f.
Retrospective study.
To report the results of a different, and previously undescribed, technique to anatomically mark the midline during cervical arthroplasty.
The ProDisc-C prosthesis should be implanted in the vertebral body midline. Current standard technique for midline marking usually relies on intraoperative fluoroscopy to locate on anteroposterior (AP) x-rays a midpoint between the uncinate processes and superimposed to the intervening spinous process. Nevertheless, uncinate process can be used as anatomic landmarks to size the proper width of the prosthesis and implant a suitable device well centered in the midline.
Two groups of ProDisc-C prostheses were analyzed and compared for midline alignment. Group 1: 68 prostheses were implanted using a different technique to identify the anatomic midline. Soft disc hernia and/or spondylotic disease (whose degree was not a contraindication for arthroplasty), either at single or multiple levels, were the underlying diseases. Group 2: 19 ProDisc-C implanted using the standard fluoroscopic technique to mark the midline.
Postoperative analysis of AP digital x-rays revealed in group 1a mean difference of -0.35 mm between the 2 halves of the prosthesis' inferior plate in respect to the defined midline. Sixty prostheses (88.2%) had an eccentric position ranging between 0.1 and 2.2 mm. Five prostheses (7.3%) were in a more significantly eccentric position by 4 to 5.5 mm. In 3 cases (4.4%), the eccentric positioning was between 2.5 and 4 mm. SD was + or - 2.18. In group 2, the mean difference was -0.07 mm. Only 1 prosthesis (5.2%) was in eccentric position by 6.14 mm. Five devices (26.3%) were in eccentric position by > or = 2 mm. The remaining 13 prostheses (68.4%) showed an eccentric position ranging between 0.36 and 1.82 mm. SD was + or - 2.02. Statistical analysis was performed using the Student t test.
This study confirms that in cases of soft disc hernia or moderate spondylosis, the anatomic midline marking technique is a safe, reliable, and effective option. It is as accurate as the current fluoroscopic-guided technique and gives the opportunity either to reduce patient's and surgeons' exposure to radiations or to shorten the operation time by reducing the overall fluoroscopy and avoiding performing AP x-rays.
回顾性研究。
报告一种不同的、此前未描述过的在颈椎置换术中对中线进行解剖学标记的技术的结果。
ProDisc-C假体应植入椎体中线。当前用于中线标记的标准技术通常依靠术中透视在前后位（AP）X线片上定位钩突之间的中点，并使其与中间的棘突重叠。然而，钩突可作为解剖学标志来确定假体的合适宽度，并将合适的装置植入中线居中位置。
分析并比较两组ProDisc-C假体的中线对齐情况。第1组：68个假体采用不同技术植入以确定解剖学中线。潜在疾病为单节段或多节段的软椎间盘疝和/或脊椎关节强硬病（其程度并非关节置换术的禁忌证）。第2组：19个ProDisc-C假体采用标准透视技术标记中线。
术后AP数字X线片分析显示，第1组中假体下板两半部分相对于确定中线的平均差异为-0.35mm。60个假体（88.2%）的偏心位置在0.1至2.2mm之间。5个假体（7.3%）的偏心位置更显著，为4至5.5mm。3例（4.4%）的偏心定位在2.5至4mm之间。标准差为±2.18。第2组的平均差异为-0.07mm。仅1个假体（5.2%）的偏心位置为6.14mm。5个装置（26.3%）的偏心位置≥2mm。其余13个假体（68.4%）的偏心位置在0.36至1.82mm之间。标准差为±2.02。采用学生t检验进行统计学分析。
本研究证实了在软椎间盘疝或中度脊椎关节强硬病的病例中，解剖学中线标记技术是一种安全、可靠且有效的选择。它与当前的透视引导技术一样准确，并且有机会减少患者和外科医生的辐射暴露，或者通过减少总体透视时间并避免进行前后位X线片来缩短手术时间。
