前路减压n—HA／PA66支撑体植骨融合内固定治疗胸腰椎爆裂骨折的中期疗效

【摘要】目的观察前路减压纳米羟基磷灰石／聚酰胺66（n—HA／PA66）支撑体治疗胸腰椎爆裂骨折的中期疗效。方法回顾性分析我科2008年1月至2009年11月行前路减压、n—HA／PA66支撑体植骨融合内固定术治疗的46例胸腰段爆裂骨折患者。男33例，女13例，平均年龄54．5岁。收集患者术前及术后胸腰椎正侧位X线片、三维CT等影像学资料以及使用Frankel分级标准评价神经功能恢复情况等临床资料；通过侧位x线片测量融合节段高度及融合节段后凸角，通过CT三维重建评价植骨融合情况。结果本组病例随访平均50（42～64）个月，至末次随访植骨融合率为97．8％。术前、术后1周、术后6个月及末次随访的平均伤椎上下椎间高度分别为94．3mm、108．0mm、106．9mm、106．2mm；平均后凸角分别为18．2°、5．7°、6．0°、6．3°。患者术后1周的融合节段高度及后凸角均较术前显著改善（P〈0．001）；术后1周、6个月及末次随访的融合节段高度及后凸角比较差异无统计学意义fP〉0．05），至末次随访时支撑体下沉平均为1．7mm。患者神经功能术前：A级3例、B级6例、C级16例、D级19例、E级2例；至末次随访：A级1例、B级2例、c级3例、D级14例、E级26例，末次随访时Frankel分级较术前有不同程度的改善。结论n—HA／PA66支撑植骨内固定能有效恢复及维持融合节段生理高度及弧度、促进植骨融合、方便术后手术节段的影像学观察，是一种较为理想的胸腰段植骨材料。使用前路减压、n—HA／PA66支撑体植骨融合内固定术治疗胸腰椎爆裂骨折的中期临床效果满意。

Medium-term results of anterior decompression and fusion with nano-hydroxyapatite/polyamide 66 cage in patients with thoracolumbar burst fractures

Objective To observe the medium-term results of anterior decompression and fusion with nano- hydroxyapatite/polyamide 66 （ n-HA/PA66 ） cage in patients with thoracolumbar burst fractures. Methods The data of 46 patients with thoracolumbar burst fractures who underwent anterior decompression and fusion with n-HA/PA66 cage in our department from January 2008 to November 2009 were retrospectively studied. There were 33 males and 13 females, whose mean age was 54.5 years old. The preoperative and postoperative imaging data of the thoracolumbar spine were collected, including the anteroposterior and lateral X-ray films and 3D-CT scans. The clinical data such as the neurological function were classified by the Frankel system. The height and sagittal kyphosis of fused segments were measured based on the lateral X-ray films, and the fusion status was assessed based on the 3D-CT scans. Results In this study, the patients were followed up for 50 months on average （ 42-64 months ）. In the latest follow-up, the fusion rate was 97.8%. The mean height of the fractured vertebral body preoperatively, on 1 and 24 weeks post- operatively and the latest follow-up was 94.3 mm, 108.0 rnm, 106.9 mm and 106.2 mm, and the mean kyphosis angle was 18.2°, 5.7°, 6.0° and 6.3°. Both the height and sagittal kyphosis of fused segments were significantly improved on 1 week after the operation compared with that preoperatively （ P〈0.001 ）. However, no statistically significant differences were found in the height or sagittal kyphosis of fused segments on 1 and 24 weeks post-operatively and in the latest follow-up （ P〉0.05 ）. An average of 1.7 mm of cage subsidence was found in the latest follow-up. The preoperative neurological function was classified, including 3 cases of grade A, 6 cases of grade B, 16 cases of grade C, 19 cases of grade D and 2 cases of grade E, and in the latest follow-up there were 1 case of grade A, 2 cases of grade B, 3 cases of grade C, 14 cases of grade D and 26 cases of grade E. According to the Frankel system, the neurological function was improved to different degrees in the latest follow-up when compared with that preoperatively. Conclusions The n-HA/ PA66 cage is a proper cage device which can effectively regain and maintain the physical height and sagittal kyphosis of fused segments, promote the osseous fusion and avoid the interference in the postoperative radiographic assessment of surgical segments. The medium-term results of anterior decompression and fusion with n-HA/PA66 cage were satisfactory in the patients with thoracolumbar burst fractures.