胸椎椎弓根螺钉置入治疗胸椎骨折的准确性和安全性评价

目的探讨胸椎椎弓根螺钉置入技术治疗胸椎骨折的准确性和安全性。方法50例胸椎骨折患者术前均行脊柱标准俯卧位CT加密扫描,测量进针点、入钉点至椎体前缘的深度、进针角度和直径,根据测得数据确定椎弓根螺钉置入的深度和方向,术后再行脊柱X线片及CT加密扫描评价置钉的准确性和安全性。结果50例患者共置入240枚胸椎椎弓根螺钉,术后CT加密扫描和X线片观察到220枚（91．7％）螺钉完全在椎弓根皮质骨内;20枚（8．3％）螺钉发生错置,其中7枚（2．9％）螺钉偏外;5枚（2．1％）螺钉偏前外侧,有2枚（0．8％）螺钉靠近主动脉;3枚（1．3％）螺钉偏下;3枚（1．3％）螺钉直径过大导致椎弓根内壁膨胀内移;2枚（0．8％）螺钉误入椎管内。螺钉完全在椎弓根皮质内的百分比在不同的胸椎节段之间有显著性差异。结论术前CT扫描测量胸椎骨折患者椎弓根的有关数据可为术中准确置入螺钉提供重要参考依据。术中标准的X线透视指导和解剖标记定位是保证胸椎椎弓根螺钉准确置入的关键因素。术后CT加密扫描能准确地反映椎弓根螺钉位置偏差,并能反映椎弓根螺钉与相邻结构的位置和关系。螺钉发生错置多见于上胸椎。     

特发性脊柱侧凸患者胸椎椎弓根的CT测量及其临床意义

目的：测量特发性脊柱侧凸患者胸椎椎弓根的有关数据，探讨其临床应用价值。方法：在30例特发性脊柱侧凸患者术前CT扫描片上测量胸椎椎弓根的宽度、深度、角度、椎体旋转角度等数据，根据所得数据选定置入螺钉的直径、长度．确定置入方向和深度。术后对置入螺钉的胸椎椎弓根节段行CT扫描，判断置钉位置。结果：CT测量的各项数据显示胸椎椎弓根适合椎弓根螺钉的置入。以此为依据术中置入胸椎弓根螺钉共245枚，228枚(93％)置入无误，6枚穿破椎弓根外壁，9枚穿破椎弓根下壁，2枚穿破椎弓根内壁，无神经系统并发症。结论：术前CT扫描测量特发性脊柱侧凸患者的胸椎椎弓根的有关数据可为选择适当长度和直径的螺钉并将其准确置入胸椎椎弓根内提供参考。从而保证螺钉安全置入。     

徒手胸椎椎弓根螺钉置入技术治疗青少年特发性脊柱侧凸的安全性评价

目的 评价徒手胸椎椎弓根螺钉置入技术治疗青少年特发性脊柱侧凸的安全性。方法从2002年7月～2004年6月对38例青少年特发性脊柱侧凸患者，徒手应用胸椎椎弓根螺钉进行后路矫形内固定，所有患者术中进行神经电生理监测及X线透视确认，术后进行X线成像、CAT扫描评估螺钉位置，并对其中35例进行随访，从而评价本技术的安全性。结果共置入胸椎椎弓根螺钉326个，每一水平置入的螺钉数如下：T1,n=2；T2，n=10;T3，n=19；T4，n=27；L，n=28；T6，n=24；T7，n=23；TB，n=25；T9，n=29；T10,n=34；T11,n=48；T12，n=57。通过胸椎CT扫描评价326枚置入畸形胸椎的螺钉位置。共有19枚螺钉（5．8％）有中等程度的皮质穿破，即螺钉的中线在椎弓根壁皮质之外，其中6枚螺钉（1．8％）穿破椎弓根内侧壁。对35例患者进行术后跟踪随访，平均随访时间2年，未发现任何与置入的胸椎椎弓根螺钉（全部326枚螺钉）相关的神经、血管或内脏并发症。结论遵循严格步骤，逐步置入胸椎椎弓根螺钉的徒手技术在治疗青少年特发性脊柱侧凸中具有可靠的安全性。     

个体化导航模板在胸椎椎弓根螺钉置入中的初步临床应用

目的:通过临床应用评价个体化导航模板辅助胸椎椎弓根螺钉置入的准确性和安全性。方法:2008年7月～2009年9月,对11例需要行胸椎椎弓根螺钉置入手术的患者(青少年特发性脊柱侧凸7例,先天性脊柱侧凸2例,胸椎结核后凸畸形1例,多发性胸椎骨折1例)术前根据CT三维重建图像利用计算机辅助设计及快速成型技术设计制作46个胸椎个体化导航模板,术中应用个体化导航模板辅助在T2～T12置入椎弓根螺钉92枚,术后CT扫描评价螺钉位置,记录有无与螺钉置入相关的并发症。结果:通过个体化导航模板辅助置入的92枚胸椎椎弓根螺钉中,83枚完全在椎弓根内,9枚穿破椎弓根壁(其中椎弓根内侧壁穿破2枚、椎弓根外侧壁穿破7枚),其中5枚螺钉因椎弓根宽度小于4mm(3.0～3.8mm)而采用椎弓根旁固定方法(椎弓根螺钉轻度穿破椎弓根外侧壁经胸肋关节内侧进入椎体),椎弓根壁非故意穿破率为4.3%,置钉准确率为95.7%,所有穿破椎弓根壁的螺钉的穿出距离均小于2mm,螺钉位置可接受率为100%。无与螺钉置入有关的神经、血管、内脏损伤等并发症的发生。结论:个体化导航模板辅助胸椎椎弓根螺钉置入的置钉准确率高,安全、可行。     

应用椎板开窗法置入胸椎椎弓根螺钉的精确性和安全性评估

目的 分析应用椎板开窗法行胸椎椎弓根螺钉置入治疗重度脊柱侧后凸患者的精确性和安全性. 方法 1996年6月至2007年12月,应用椎板开窗法行胸椎椎弓根螺钉置入治疗23例重度脊柱侧后凸患者(A组),其中男性9例,女性14例;年龄13～23岁,平均17.8岁;术前主胸弯冠状面Cobb角平均97.3°,平均后凸角67.4°.作为对照,同期应用非开放法置钉治疗重度脊柱侧后凸患者22例(B组),其中男性7例,女性15例;年龄14～21岁,平均17.2岁;术前主胸弯冠状面Cobb角平均为96.6°,平均后凸角62.1°.两组患者术后均行CT扫描,统计螺钉置入并发症,对螺钉穿透椎弓根皮质骨的CT扫描图像进行联机测量并统计分析.结果 A组和B组各置入胸椎椎弓根螺钉209和201枚,术中发生椎弓根骨折5例和16例,发生硬膜撕裂4例和7例,螺钉错置18枚和45枚.B组螺钉错置率高于A组,差异具有统计学意义(P<0.05).A组上、中胸椎与下胸椎之间、凸侧与凹侧之间,螺钉错置率差异均具有统计学意义(P<0.05).两组均无脊髓及大血管损伤. A和B组经平均3.2年、3.4年随访,术后冠状面和矢状面平均矫正度未见明显丢失.结论 重度脊柱侧后凸胸椎椎弓根螺钉置入技术难度较高,应用椎板开窗法可有效增加螺钉置入精确性和安全性.     

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

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。     

全椎弓根螺钉技术治疗特发性脊柱侧凸

目的：探讨在脊柱侧凸后路矫正术中采用全脊柱椎弓根螺钉技术的疗效。方法：2002年6月至2005年10月，采用全脊柱椎弓根螺钉技术治疗特发性脊柱侧凸56例，男11例，女45例；年龄8-22岁。侧凸程度按Cobb测量法评估，Cobb角45°-85°，平均62.45°。侧凸按Lenke分型：1型29例，2型6例，3型8例，4型2例，5型8例，6型3例。结果：平均手术时间3h20min，平均出血600ml，T1-L4共置椎弓根螺钉425枚，其中腰椎弓根螺钉181枚，胸椎椎弓根螺钉244枚。术后所有患者均经CT扫描检查，结果发现腰椎弓根螺钉全部准确置入，244枚胸椎椎弓根螺钉中116枚完全通过椎弓根进入椎体，119枚通过肋骨横突复合结构进入椎体，9枚穿破椎弓根内侧壁，置钉准确率96．8％，术中术后均未出现神经血管并发症。手术切口除2例浅表感染，均I期愈合。全部患者均获随访，时间5-40个月，平均22．5个月，术后均无疼痛，X线正侧位及动态位片未见内固定松动断裂及假关节形成。术后Cobb角平均18°，平均矫正44°，矫正率72．5％。所有患者均在4-8个月内恢复正常的生活、学习和工作状态。结论：脊柱侧凸后路矫正术中采用全脊柱椎弓根螺钉技术是一种安全、有效的方法，能取得较好的矫正效果及较少的并发症。熟悉解剖并结合CT扫描，术前进行准确测量及术中的仔细操作对手术成功非常重要。     

个体化选择脊柱侧凸患者胸椎椎弓根螺钉进钉点的研究

目的:探讨个体化选择脊柱侧凸患者胸椎椎弓根螺钉进钉点对置钉准确性的影响.方法:2006年3月至2008年6月手术治疗脊柱侧凸患者57例,其中青少年特发性脊柱侧凸44例,先天性脊柱侧凸12例,马凡综合征1例.根据患者术前CT设计拟固定胸椎的椎弓根螺钉进钉点并用于指导术中的进钉点选择,术后根据螺钉是否突破椎弓根的皮质壁来判断置钉准确性.结果:全部患者共置入椎弓根螺钉591枚,胸椎417枚,腰椎174枚,术后530枚螺钉的轴线完全位于椎弓根皮质内,准确率为89.7%, 其中胸椎置钉准确率为86.8%(362,417).61枚螺钉的轴线突破椎弓根皮质壁,胸椎55枚,腰椎6枚.55枚偏置的胸椎椎弓根螺钉中52枚螺钉的实际进钉点与术前设计一致,其中19枚钉尖位于椎体内;3枚螺钉为术中实际进钉点选择失误,螺钉轴线突破椎弓根皮质壁的距离均不超过4mm.无脊髓、大血管及脏器损伤等严重并发症发生.结论:个体化选择胸椎椎弓根螺钉进钉点可提高脊柱侧凸患者胸椎置钉的准确率,减少术中进钉点选择失误所致的并发症.     

非影像监视下行脊柱侧凸胸椎椎弓根螺钉置入的临床应用

目的:探讨脊柱侧凸胸椎椎弓根螺钉非影像监视下徒手置入的方法及可行性。方法:57例脊柱侧凸患者行后路椎弓根螺钉系统矫形手术,徒手法置入胸椎椎弓根螺钉。术后常规拍摄脊柱全长X线片,随机选取10例患者行CT扫描观察,了解螺钉置入的准确性。结果:共置入胸椎椎弓根螺钉362枚。术后X线片观察到10枚螺钉偏外,4枚螺钉偏下,其中2枚螺钉引起轻微肋间神经痛,3周后完全缓解。CT观察47枚螺钉有2枚螺钉导致椎弓根内壁膨胀内移,没有相应神经症状。主弯Cobb角术前平均60.4°(32°～121°),术后平均18.3°(1°～70°),平均矫正率71.9%(38.1%～98.0%)。结论:徒手法置入脊柱侧凸胸椎椎弓根螺钉是可行的。     

成人腰椎侧凸椎弓根螺钉误置模式

目的探讨成人腰椎侧凸椎弓根螺钉误置模式并分析其危险因素。方法选取2010年8月至2011年6月行后路全椎弓根螺钉固定的成人腰椎侧凸患者49例,男14例,女35例;年龄30～65岁,平均39．2±13．8岁。术中根据解剖标志徒手置入椎弓根螺钉,术后行CT检查。破壁螺钉按测量螺钉穿破椎弓根内、外侧壁及椎体前缘的距离分为4级：1级≤2mm,2级2．1—4．0mm,3级4．1～6．0mm,4级≥6．1mm。不良置钉为穿透任一壁距离超过2mm者,高危置钉为穿破内侧壁超过4mm或穿破外侧壁顶尖使主动脉变形者。比较不同分组螺钉破壁率的差异。结果49例共置入353枚螺钉,平均每例7．2枚。螺钉完全在椎弓根内且无椎体前缘穿破316枚（占89．5％）。破壁螺钉37枚（占10．5％）,根据破壁距离分级：1级25枚,2级8枚,3级1枚,4级3枚。不良置钉12枚（占3．4％）,其中穿破内、外侧壁及椎体前缘超过2mm分别为3枚、6枚、3枚。无高危置钉。螺钉破壁率：年龄〉50岁组为9．9％与年龄≤50岁组为10．9％无显著性差异（P=0．860）;顶椎（apicalvertebra,AV）高于AV上下各节段;凹侧为15．6％明显高于凸侧为5．9％（P=0．005）;Cobb角〉60°组为20．2％显著高于Cobb角≤60。组为6．1％（P〈0．001）。椎体旋转3—4度组为16．5％明显高于椎体旋转0～2度组为6．5％（P=0．012）。患者术中及术后均未出现神经并发症。结论成人腰椎侧凸椎弓根螺钉置人具有较高的精确性,破壁螺钉及不良置钉主要位于AV及凹侧,危险因素包括较大Cobb角、严重椎体旋转以及凹侧置钉。     

Accuracy and safety of thoracic pedicle screw placement in spinal deformities

OBJECTIVES: To determine the safety of pedicle screw fixation in thoracic spine deformity correction. METHODS: One hundred twelve pedicle screws were surgically placed in 25 patients with degenerative, posttraumatic, and Scheuermann kyphosis and idiopathic and neuromuscular scoliosis. Screw position was evaluated using intraoperative and postoperative radiographs and thin-slice computed tomography. RESULTS: Of the total 112 thoracic pedicle screws that were inserted, 98 screws (87.5%) were fully contained within the cortical boundaries of the pedicle. When comparing proximal screws (T1-T8) with distal screws (T9-T12) and convex placed screws with concave ones, a statistically significant difference in screw placement was evident (P < 0.05). More misplaced screws were seen proximally and on the concave side. Of the 14 malpositioned screws, 2 (1.8%) demonstrated aortic abutment. There were no neurologic deficits, vascular injuries, or mechanical failures recorded. CONCLUSIONS: Placement of thoracic pedicle screws is both feasible and safe.     

Accuracy of robot-assisted pedicle screw placement for adolescent idiopathic scoliosis in the pediatric population

This is a retrospective review of pedicle screw placement in adolescent idiopathic scoliosis (AIS) patients under 18 years of age who underwent robot-assisted corrective surgery. Our primary objective was to characterize the accuracy of pedicle screw placement with evaluation by computed tomography (CT) after robot-assisted surgery in AIS patients. Screw malposition is the most frequent complication of pedicle screw placement and is more frequent in AIS. Given the potential for serious complications, the need for improved accuracy of screw placement has spurred multiple innovations including robot-assisted guidance devices. No studies to date have evaluated this robot-assisted technique using CT exclusively within the AIS population. Fifty patients were included in the study. All operative procedures were performed at a single institution by a single pediatric orthopedic surgeon. We evaluated the grade of screw breach, the direction of screw breach, and the positioning of the patient for preoperative scan (supine versus prone). Of 662 screws evaluated, 48 screws (7.2 %) demonstrated a breach of greater than 2 mm. With preoperative prone position CT scanning, only 2.4 % of screws were found to have this degree of breach. Medial malposition was found in 3 % of screws, a rate which decreased to 0 % with preoperative prone position scanning. Based on our results, we conclude that the proper use of image-guided robot-assisted surgery can improve the accuracy and safety of thoracic pedicle screw placement in patients with adolescent idiopathic scoliosis. This is the first study to evaluate the accuracy of pedicle screw placement using CT assessment in robot-assisted surgical correction of patients with AIS. In our study, the robot-assisted screw misplacement rate was lower than similarly constructed studies evaluating conventional (non-robot-assisted) procedures. If patients are preoperatively scanned in the prone position, the misplacement rate is further decreased.     

Accuracy and safety of pedicle screw placement in neuromuscular scoliosis with free-hand technique

It is a retrospective analytic study of 1,009 transpedicular screws (689 thoracic and 320 lumbosacral), inserted with free-hand technique in neuromuscular scoliosis using postoperative CT scan. The aim of paper was to determine the accuracy and safety of transpedicular screw placement with free-hand technique in neuromuscular scoliosis and to compare the accuracy at different levels in such population. All studies regarding accuracy and safety of pedicle screw in scoliosis represent idiopathic scoliosis using various techniques such as free-hand, navigation, image intensifier, etc., for screw insertion. Anatomies of vertebrae and pedicle are distorted in scoliosis, hence accurate and safe placement of pedicle screw is prerequisite for surgery. Between 2004 and 2006, 37 consecutive patients, average age 20 years (9–44 years), of neuromuscular scoliosis were operated with posterior pedicle screw fixation using free-hand technique. Accuracy of pedicle screws was studied on postoperative CT scan. Placement up to 2 mm medial side and 4 mm lateral side was considered within-safe zone. Of the 1,009 screws, 273 screws were displaced medially, laterally or on the anterior side showing that 73% screws (68% in thoracic and 82.5% in lumbar spine) were accurately placed within pedicle. Considering the safe zone, 93.3% (942/1009, 92.4% in thoracic and 95.3% in lumbar spine) of the screws were within the safe zone. Comparing accuracy according to severity of curve, accuracy was 75% in group 1 (curve <90°) and 69% in group 2 (curve >90°) with a safety of 94.8 and 91.2%, respectively (P = 0.35). Comparing the accuracy at different thoracic levels, it showed 67, 64 and 72% accuracy in upper, middle and lower thoracic levels with safety of 96.6, 89.2 and 93.1%, respectively, exhibiting no statistical significant difference (P = 0.17). Pedicle screw placement in neuromuscular scoliosis with free-hand technique is accurate and safe as other conditions.     

Evaluation of a transpedicular drill guide for pedicle screw placement in the thoracic spine

Insertion of pedicle screws in the thoracic spine is technically difficult and may lead to major complications. Although many computer-assisted systems have been developed to optimize pedicle screw insertion, these systems are expensive, not user-friendly and involve significant radiation from pre-operative computed tomographic (CT) scan imaging. This study describes and evaluates a transpedicular drill guide (TDG) designed to assist in the proper placement of pedicle screws in the thoracic spine. Pilot holes were made manually using the TDG in the thoracic spine (T1-T11) of three human cadavers before inserting 4.5-mm-diameter screws. CT scans followed by visual inspection of the spines were performed to evaluate the position of the screws. Five of 66 screws (7.6%) violated the pedicle wall: two (3.0%) medially and three (4.5%) laterally. The medial and lateral perforations were within 1 mm and 2 mm of the pedicle wall, respectively. The medial perforations were not at risk of causing neurological complications. No screw penetrated the superior or inferior pedicle wall. The TDG is easy to use and can decrease the incidence of misplaced thoracic pedicle screws. The TDG could be used as a complement to fluoroscopy in certain applications, especially for training surgeons.     

Inserting pedicle screws in the upper thoracic spine without the use of fluoroscopy or image guidance. Is it safe?

Several studies have looked at accuracy of thoracic pedicle screw placement using fluoroscopy, image guidance, and anatomical landmarks. To our knowledge the upper thoracic spine (T1–T6) has not been specifically studied in the context of screw insertion and placement accuracy without the use of either image guidance or fluoroscopy. Our objective was to study the accuracy of upper thoracic screw placement without the use of fluoroscopy or image guidance, and report on implant related complications. A single surgeon inserted 60 screws in 13 consecutive non-scoliotic spine patients. These were the first 60 screws placed in the high thoracic spine in our institution. The most common diagnosis in our patient population was trauma. All screws were inserted using a modified Roy-Camille technique. Post-operative axial computed tomography (CT) images were obtained for each patient and analyzed by an independent senior radiologist for placement accuracy. Implant related complications were prospectively noted. No pedicle screw misplacement was found in 61.5% of the patients. In the remaining 38.5% of patients some misplacements were noted. Fifty-three screws out of the total 60 implanted were placed correctly within all the pedicle margins. The overall pedicle screw placement accuracy was 88.3% using our modified Roy-Camille technique. Five medial and two lateral violations were noted in the seven misplaced screws. One of the seven misplaced screws was considered to be questionable in terms of pedicle perforation. No implant related complications were noted. We found that inserting pedicle screws in the upper thoracic spine based solely on anatomical landmarks was safe with an accuracy comparable to that of published studies using image-guided navigation at the thoracic level.     

颈椎后路双开门脊髓减压椎弓根内固定术治疗颈椎骨折脱位的效果分析

目的探讨颈椎后路双开门脊髓减压椎弓根内固定术治疗颈椎骨折脱位并脊髓损伤患者的治疗效果。方法2000年12月至2008年4月,行颈椎后路双开门脊髓减压椎弓根内固定术治疗38例颈椎骨折脱位并脊髓损伤患者,男28例,女10例;年龄20-80岁,平均43．5岁;颈椎损伤节段：C22例,C33例,C410例,C513例,C68例,C72例。术后行椎弓根螺钉CT检查并观察脊髓神经功能改善状况。结果38例患者C2-7共置入椎弓根螺钉158枚,其中152枚（96．2％）完全置入椎弓根皮质骨内,6枚（3．8％）置入位置不准确,包括进钉位置偏内经椎板进入椎管2枚,偏外挤穿椎弓根外侧皮质4枚。术后随访36例,随访时间1-36个月,平均6．8个月;脊髓神经损伤ASIA分类：A级7例、B级15例、C级13例、D级3例,A级的7例患者中5例感觉下降,恢复至B级;2例感觉完全恢复,上肢肌力有改善,但下肢运动功能无改善,分别恢复至C、D级。其余均有1-3级的功能恢复。无1例继发性血管、神经损伤。结论早期行后路双开门脊髓减压椎弓根内固定术以保持颈椎损伤阶段的稳定性,对颈椎骨折脱位并脊髓损伤患者的功能恢复有显著治疗作用。