低龄儿童脊柱侧凸矫正术中椎弓根螺钉置入的精确性和安全性评估

Safety and accuracy of pedicle screw placement in pediatric patients with spinal deformity

中文关键词:  椎弓根螺钉  儿童  CT扫描  并发症  脊柱侧凸

英文关键词:Ｐedicle screw  Ｐediatric  Ｓpinal deformity  Ｃomplication  Ｓpinal deformity

中文摘要:

  【摘要】 目的：评估10岁及以下脊柱侧凸患儿侧凸矫正术中椎弓根螺钉置入的精确性及安全性，并分析其相关影响因素。方法：回顾性分析2008年2月~2008年7月我院收治的行后路椎弓根螺钉固定的10岁及以下脊柱侧凸41例患儿的临床资料，所有患者术前、术后均行CT检查，男26例，女15例，年龄2~10岁，平均5.4岁。先天性脊柱侧凸36例，特发性脊柱侧凸2例，神经肌肉源性脊柱侧凸2例，先天性软骨发育不全伴脊柱侧凸1例。术中根据解剖标志徒手置入椎弓根螺钉。在PACS系统上通过Pacs Client软件测量螺钉尖距椎弓根内壁、外壁、上壁、下壁以及椎体前缘的距离。若左侧椎弓根螺钉穿破椎弓根外壁或椎体前缘，测量钉尖与主动脉的距离。根据椎弓根螺钉所在位置（节段、凹凸侧、脊椎发育是否异常）分析其破壁率差别。不良置钉定义为椎弓根螺钉穿破椎弓根内、外壁或椎体前缘的距离超过2mm，和椎弓根螺钉进入椎间孔或穿破终板进入椎间盘。结果：本组病例共置入242枚椎弓根螺钉，胸椎128枚，腰椎114枚，平均每例患者置入5.8枚螺钉。螺钉完全在椎弓根内208枚，占86.0%。破壁34枚（占14.0％），其中不良置钉18枚（占7.4%），18枚中有5枚穿破外壁，8枚穿破内壁，5枚穿破椎体前缘。形态异常椎和凹侧的椎弓根螺钉的破壁率较高（分别为24.1%和17.9%）。术中一枚螺钉拔出，未出现其他螺钉置入相关并发症。穿破椎体前缘螺钉距离主动脉距离平均2.3mm。结论：10岁及以下儿童椎弓根螺钉的徒手置入有较高的精确性和安全性，但在发育不良椎体及凹侧置钉时应谨慎。

英文摘要:

  【Abstract】 Objective：To investigate the safety and accuracy of pedicle screw placement in pediatric scoliosis patients and its possible risk factors.Methods:Forty one consecutive cases from Feb. 2008 to Jul. 2008 undergoing posterior pedicle screw instrumentation were retrospectively reviewed.There were 15 girls and 26 boys，with a mean age of 5.4 years at surgery（range，2-10 years）.The diagnoses included congenital scoliosis （n=36），idiopathic scoliosis　（n=2），neuromuscular scoliosis（n=2），scoliosis associated with achondroplasia （n=1）.Free-hand pedicle screw placement was performed based on the anatomic landmark.Postoperative CT scans were performed in all cases.The extent of medial，lateral and anterior perforation were measured using Pacs Client software（PACS）.The distance between aorta and screw tip was measured if the left pedicle screw penetrated lateral wall or anterior vertebral cortex.The misplacement was defined as pedicle screws breaking medial，lateral，anterior vetebral cortex more than 2mm or perforating endplate and neural foramen.Result:A total of 242 pedicle screws were inserted，128 in thoracic spine and 114 in lumbar area，with an average of 5.8 screws for each patient.208　screws（86.0%） were sited completely in pedicle.18 screw malposition was noted（breaking more than 2mm），5 of which penetrated lateral pedicle cortex，8 penetrated medial pedicle cortex，and 5 penetrated vertebral anterior cortex.The vertebra with malformation or at the concave side had higher perforation rate（24.1% and 17.9% respectively）．The mean distance between the screw tip and the anterior wall was 2.3mm for eight screws breaking the anterior wall.Screw loosening occurred in one patient.Conclusions:For children less than 10 years old，free-hand screw placement is of high accuracy and safety；however the vertebra with malformation or at the concave side should be paid attention.