Ouchida Jun, Yukawa Yasutsugu, Ito Keigo, Machino Masaaki, Inoue Taro, Tomita Keisuke, Kato Fumihiko
Department of Orthopedic Surgery, Chubu Rosai Hospital, Japan Labor Health and Welfare Organization, 1-10-6 Komei, Minato-ku, Nagoya, Aichi, 455-8530, Japan.
Eur Spine J. 2015 Dec;24(12):2924-9. doi: 10.1007/s00586-014-3722-z. Epub 2014 Dec 24.
Nonunion is a major complication of anterior cervical fusion that causes poor outcomes and occasionally requires additional operative intervention. The purpose of this study is to evaluate the accuracy of functional computed tomography (CT) scanning for determining fusion status after anterior cervical fusion by comparing with functional radiographs.
The fusion status in 59 patients treated by anterior cervical fusion was assessed by functional radiography and functional CT scanning at 6 and 12 months after surgery. Fusion rates and clinical symptoms were evaluated. Fusion on functional radiography was defined as less than 2 mm of motion between adjacent spinous processes and a particular bony trabeculation on functional CT; fusion was defined as nonexistence of a clear zone or a gas pattern and a particular bone connection on reconstructed sagittal-view images.
Functional radiographs demonstrated solid fusion in 83.9% at 6 months and 91.1% at 12 months postoperatively; functional CT showed solid fusion in 55.3 and 78.6%, respectively. The fusion rate detected on functional CT images was significantly lower than that on functional radiographs at each period. At 6 months postoperatively, patients with incomplete union on functional CT were more likely to have neck pain than those who had complete union on functional CT. (46.2 vs 13.3%, P < 0.05) CONCLUSION: Functional CT can detect nonunion more clearly than functional radiography. At 6 months postoperatively, patients with incomplete union on functional CT images were likely to have more neck pain. Functional CT may allow accurate detection of symptomatic nonunion after anterior cervical fusion.
骨不连是颈椎前路融合术的一种主要并发症，会导致预后不良，偶尔还需要额外的手术干预。本研究的目的是通过与功能X线片比较，评估功能计算机断层扫描（CT）在确定颈椎前路融合术后融合状态方面的准确性。
对59例行颈椎前路融合术的患者，在术后6个月和12个月时通过功能X线片和功能CT扫描评估融合状态。评估融合率和临床症状。功能X线片上的融合定义为相邻棘突间运动小于2mm以及功能CT上特定的骨小梁形成；融合在重建矢状位图像上定义为不存在清晰区域或气体样表现以及特定的骨连接。
功能X线片显示术后6个月时牢固融合率为83.9%，12个月时为91.1%；功能CT分别显示为55.3%和78.6%。在每个时间段，功能CT图像检测到的融合率显著低于功能X线片。术后6个月，功能CT显示未完全融合的患者比完全融合的患者更易出现颈部疼痛（46.2%对13.3%，P<0.05）。结论：功能CT比功能X线片能更清晰地检测到骨不连。术后6个月，功能CT图像显示未完全融合的患者可能颈部疼痛更明显。功能CT可能有助于准确检测颈椎前路融合术后有症状的骨不连。
