单向和多向胸椎椎弓根钉在青少年特发性脊柱侧凸矫形手术中的疗效分析

目的 分析比较单向和多向椎弓根螺钉用于矫正青少年特发性脊柱侧凸的临床疗效.方法 2001年2月～2004年9月,55名Lenke I型的青少年特发性脊柱侧凸患者用后路Mossmiami内固定系统进行矫形融合手术.其中30例应用单向钉,25例应用多向钉.所有患者随访时间超过2年,分别测量2组患者术前及术后上胸弯、主胸弯、胸腰弯Cobb角,肋骨椎体比以及肋骨分离距离等.结果 平均融合椎体分别为7.9个(单向钉组)和7.2个(多向钉组).2种方法都取得了良好的主胸弯的矫正效果,矫正率单向钉组为65.9%,多向钉组60%.单向钉用于矫正剃刀背畸形明显优于多向钉.2组患者都未出现明显的并发症.结论 单向钉和多向钉对于主胸椎侧凸冠状位矫形都有良好的效果,但是单向钉比多向钉具有更好的去旋转以及恢复胸椎对称性的作用.     

King Ⅱ型特发性脊柱侧凸的手术治疗

目的：探讨King Ⅱ型特发性脊柱侧凸患者三维矫形融合节段的选择。方法：1997年7月～2002年6月手术矫形治疗King Ⅱ型特发性脊柱侧凸患者79例，平均年龄14．3岁，其中King Ⅱ A型28例，均行选择性胸椎融合，平均融合椎体8．5个；King ⅡB型51例，均固定融合胸椎与腰椎，平均融合椎体11．8个。结果：术后平均随访35个月(12～57个月)，King ⅡA型胸弯矫正率为56％，King ⅡB型的胸弯矫正率为67％，腰弯矫正率为60％。共有5例躯干失平衡并发症，其余患者均获得较好的躯干平衡和矫形效果。结论：KingII型特发性脊柱侧凸进行选择性胸椎融合是可行的，但应慎重。     

置钉密度与Lenke1型青少年特发性脊柱侧凸矫正率的相关性

[目的]回顾性分析全椎弓根螺钉矫形治疗Lenke 1型青少年特发性脊柱侧凸矫正率与置钉密度间的相关性.[方法]2007～2009年,56例行后路全椎弓根螺钉矫形内固定的Lenke 1型青少年特发性脊柱侧凸患者纳入回顾性研究.测量术前、术后影像学资料,分析侧凸矫正率与置钉密度的相关性.[结果]所有患者无手术相关的严重并发症发生.主胸弯角度由术前平均53.4°±11.7°矫正为18.4°±10.5°(P<0.05),冠状面平均矫正率为66.8%.胸椎后凸由术前31.8°±4.39°降至22.3°±3.13°(P<0.05).平均置钉密度为1.56 (1.0～2.0).矢状面胸椎后凸的减小与冠状面Cobb角的矫正度数和矫正率明显相关(P<0.05).置钉密度与侧凸矫正率无相关性.[结论]椎弓根螺钉系统治疗胸椎特发性侧凸可以获得良好的冠状面矫形,但会造成矢状面胸椎后凸减小.置钉密度与侧凸的矫正率无相关性.     

青少年特发性胸椎侧凸前路矫形:开放与微创的选择

后路矫形一直是青少年特发性胸椎侧凸矫形的标准术式。随着对脊柱侧凸理论研究的深入和矫形技术的进步，特别是前路手术通过矫形力直接作用于侧方移位和旋转的椎体，可获得更好的矫正冠状面畸形、重建平衡以及减少椎体水平面旋转，另外通过压缩椎体螺钉矫正侧凸畸形，可以有效恢复胸椎正常后凸，并通过缩短而不是延长脊柱而矫正侧凸，因此减少了因牵拉脊髓而致神经损伤的可能性，使得胸弯前路矫形在近年越来越受到关注和重视。近年来国外又涌现出很多前路矫形手术的报道，特别是胸腔镜微创矫形技术的应用，     

King Ⅲ型特发性脊柱侧凸经胸侧前方椎体三维矫形术

[目的]探讨King Ⅲ型特发性脊柱侧凸经胸侧前方椎体三维矫形术的治疗效果。[方法]回顾本院2003年9月-2005年9月应用TSRH、CDH-M。等矫形器械对12例青少年King Ⅲ型特发性脊柱侧凸患者经凸侧胸腔于椎体侧前方行椎间松解、椎体三维矫形、植骨融合内固定术的临床资料，分析评价其手术并发症、侧凸矫正率及随访结果。[结果]术后出现肺部并发症2例，1例肺不张，1例呼吸道梗阻。经气管插管和呼吸机辅助呼吸后缓解。所有病例均未出现大血管损伤、脊髓损伤、肺炎和乳糜胸等并发症。术前胸椎Cobb’s角48^o～66^o，平均52．6^o。术后胸椎残余Cobb，s角平均15.2^o，矫正率77．8％。随访12～36个月，平均18．5个月。12例患者均获得了较好的节段性骨融合，矫正率无明显丢失，未发现假关节、内固定松动或断裂、失代偿等并发症。[结论]经胸椎体侧前方二维矫形手术是治疗King Ⅲ型特发性脊柱侧凸畸形的一种较安全、有效的内固定方式。     

内固定方式对青少年特发性脊柱侧凸选择性胸椎融合矢状面重建的影响

目的 探讨胸弯型青少年特发性脊柱侧凸患者行后路选择性胸椎融合术时采用不同内固定方式对胸椎矢状面形态及远端腰椎代偿模式的影响.方法 行胸弯后路矫形内同定术且有2年以上(2～3年)完整随访资料的lenke 1、2型青少年特发性脊柱侧凸患者51例,按内固定方式分为A组(全钩组)、B组(钩钉混合组)和C组(全钉组).测量术前及术后随访的胸弯Cobb角、腰弯Cobb角、胸椎后凸角、腰椎前凸角、远端交界性后凸、胸腰段交界性后凸及C7铅垂线偏离S1后上缘的距离.结果 三组患者主弯矫正率均大于60%,继发弯也获得较满意的自发性矫正.三组患者术前及随访中腰椎前凸角、C7铅垂线偏离S1后上缘的距离均保持正常.随访2年时,A组远端交界性后凸、胸椎后凸角、胸腰段交界性后凸分别达3.6°、23.0°、6.4°,其中远端交界性后凸与术前比较差异有统计学意义(P<0.05).B组和C组各项指标与术前比较差异均无统计学意义.结论 全钩型同定可以获得良好的冠状面矫形,且在随访中能保持腰椎前凸和欠状面平衡.但钩的固定不如椎弓根螺钉牢固,全钩型固定患者胸椎后凸角有增大趋势,胸腰椎交界区有失代偿的可能.     

近端固定椎的选择对Lenke 5型脊柱侧凸前路矫形疗效的影响

  目的 探讨近端固定椎的选择对Lenke 5型脊柱侧凸前路融合术矫形疗效的影响。方法 2002年1月至2006年12月接受前路选择性单棒矫形手术治疗 且获得2年以上随访的女性Lenke 5型青少年特发性脊柱侧凸患者36例,近端固定至上端椎21例、近端固定至上端椎下方椎体15例。两组患者平均年龄为（15.3± 1.8）岁和（15.5±1.9）岁,平均胸腰或腰主弯Cobb角为46.2°和46.7°,近端胸弯为26.3°和29.6°。平均融合节段为5.3和4.8个椎体。结果 两组平均随访 31和33个月。冠状面胸腰或腰主弯矫正率为79%和70%（P=0.062）,近端胸弯自发矫正率为46%和29%（P=0.044）。矢状面上,术前和术后两组患者腰椎前凸角、 骶骨倾斜角差异均无统计学意义。矢状面平衡维持于较小的负平衡。胸椎后凸角分别有4.0°和2.3°的轻度增加,末次随访时近端固定至上端椎组大于近端固定 至上端椎下方椎体组（P=0.029）。胸腰段交界性成角均表现为轻度后凸增加,并最终保持2°~4°后凸角。近端交界性后凸均有轻度增加,融合节段成角均呈前 凸减小甚至出现后凸趋势。结论 Lenke 5型脊柱侧凸行前路选择性融合术中,近端融合至上端椎较固定至端椎下方椎体可获得更好的冠状面主弯矫正和近端胸弯 自发性矫正,矢状面矫形效果相似。     

采用关键椎置钉及选择性融合治疗Lenke6型AIS可行性的有限元分析

[目的]通过有限元模型矫形手术模拟的方法探讨关键椎置钉技术的可行性及矫形效果,分析Lenke 6型脊柱侧凸是否适合采用选择性融合策略.[方法]通过CT图像建立1例Lenke 6型特发性脊柱侧凸三维有限元模型,并验证其有效性后,利用后路CD矫形手术模拟技术,分别模拟全节段椎弓根钉技术矫形工况、关键椎置钉技术矫形工况、胸腰弯选择性融合工况等.测量各种工况完成后双弯Cobb角度、计算矫形率,分析各种工况的矫形效果.[结果]全节段椎弓根钉技术(非选择性融合):胸腰弯矫形率47.8％,主胸弯矫形率43.9％;关键椎置钉技术:胸腰弯矫形率44.2％,主胸弯矫形率19.1％;胸腰弯选择性融合:胸腰弯矫形率43.5％,主胸弯矫形率14.3％.[结论]全节段椎弓根钉技术因矫形力施加点更多,矫形效果较关键椎置钉技术更佳;Lenke 6型脊柱侧凸采用选择性融合策略应慎重,非选择性融合策略能明显矫正双弯,纠正脊柱序列,更适合该类型病例.     

脊柱侧凸微创技术(续)

3胸椎侧凸胸腔镜下矫形术 3．1适应证和禁忌证 由于镜下操作难度大，矫形力应用受限，因此胸腔镜下脊柱侧凸矫形手术仅适用于年龄较轻、Cobb角较小、侧凸较柔软、脊柱矢状面形态正常或有轻度前凸的特发性胸椎侧凸病人，对于KingⅡ型和KingⅢ型脊柱侧凸尤其适合。对于KingⅤ型脊柱侧凸，可采用选择性融合技术，即上胸弯较柔软时可仅融合下胸弯。对于Risser小于2的病人，胸腔镜Eclipse矫形术可消除椎体的生长潜能，防止“曲轴效应”的发生。Picetti于1996年10月开展了第一例胸腔镜     

先天性脊柱侧凸后路融合内固定术后肺部并发症的危险因素分析

目的探讨先天性脊柱侧凸后路融合内固定术后出现肺部并发症的危险因素。方法回顾性分析自2012-01—2017-12采用后路融合内固定治疗的276例先天性脊柱侧凸,39例后路融合内固定术后出现肺部并发症(观察组),237例后路融合内固定术后未出现肺部并发症(对照组)。分析先天性脊柱侧凸后路融合内固定术后出现肺部并发症的危险因素。结果单因素分析结果显示2组在年龄、性别、病史时间、再手术数、术前肺部疾病、主弯位置、术前侧凸Cobb角、侧凸Cobb角矫正率、椎体融合节段、上胸椎置钉、中胸椎置钉、下胸椎置钉、胸廓成形、手术时间、输血量、RV/TLC比较差异有统计学意义(P0.05),多因素Logistic回归分析结果显示年龄、再手术、术前合并肺部疾病、侧凸Cobb角矫正率、中胸段置钉和胸廓成形术是先天性脊柱侧凸后路融合内固定术后出现肺部并发症的危险因素。结论年龄、术前肺部疾病、再手术、侧凸Cobb角矫形率、中胸椎螺钉固定、胸廓成形术是先天性脊柱侧凸后路融合内固定术后出现肺部并发症的危险因素。     

单平面椎弓根螺钉矫正Lenke 5型青少年特发性脊柱侧凸顶椎旋转

目的对单平面椎弓根螺钉和万向椎弓根螺钉矫正Lenke 5型青少年特发性脊柱侧凸(AIS)顶椎旋转的效果进行对比分析。方法回顾性分析2010年1月—2013年12月收治的72例应用万向/单平面椎弓根螺钉行后路三维矫形植骨融合内固定术的Lenke 5型AIS患者的临床资料,其中使用万向椎弓根螺钉治疗(A组)43例,使用单平面椎弓根螺钉治疗(B组)29例。记录手术前后腰椎侧凸Cobb角和腰椎前凸角,并计算侧凸矫正率。术前使用Nash-Moe法评估顶椎旋转程度,术后根据Upasani等提出的X线椎体旋转分级标准评价顶椎去旋转的效果。结果所有患者均顺利完成手术。2组患者术前侧凸Cobb角及腰椎前凸角差异无统计学意义(P 0.05);2组术后2周及1年侧凸Cobb角及腰椎前凸角均较术前显著改善,差异有统计学意义(P 0.05);A组术后1年侧凸矫正率为79.2%,B组为81.4%,差异无统计学意义(P 0.05)。2组患者术前顶椎旋转程度差异无统计学意义(P 0.05);术后2周及1年顶椎去旋转程度B组优于A组,差异有统计学意义(P 0.05)。结论两种椎弓根螺钉都能很好地矫正Lenke 5型AIS患者冠状面侧凸,单平面椎弓根螺钉在矫正及维持顶椎去旋转效果方面优于万向椎弓根螺钉。     

顶椎置钉与否对Lenke 1型青少年特发性脊柱侧凸矫形效果的影响

目的:探讨顶椎置钉与否对Lenke 1型青少年特发性脊柱侧凸(AIS)患者矫形效果的影响。方法:回顾性分析从2009年6月～2010年1月采用全椎弓根螺钉后路矫形内固定融合术治疗的69例Lenke 1型AIS患者,年龄12～20岁,平均15.0岁,主弯Cobb角50°～70°,平均53.7°。根据顶椎置钉与否分为:顶椎凸凹侧均未置入螺钉组(A组,35例)和至少一侧置入螺钉固定组(B组,34例)。记录两组患者术前年龄、性别、主弯Cobb角、柔韧度、顶椎旋转度和固定节段数、置入物密度、术后Cobb角、主弯Cobb角矫正率、顶椎去旋转率等指标并进行两组间的比较分析。B组病例在CT图像上统计顶椎不良置钉率。结果:两组患者年龄、性别比、术前主弯Cobb角、柔韧度和顶椎旋转度等资料均无统计学差异(P>0.05)。所有病例矫形术后均未发生冠状面与矢状面的失代偿。随访24～30个月,平均27.7个月,两组患者无内固定松动及断钉断棒,植骨融合牢固,均未出现明显的矫正丢失。A、B两组置入物密度分别为63.4%、65.3%,平均固定节段数分别为11.3和11.6,主弯Cobb角矫正率分别为73.9%和72.6%。两组在置入物密度、内固定节段数和主弯Cobb角矫正率方面均无统计学差异(P>0.05)。术后顶椎去旋转率A组为18.4%,显著低于B组的34.8%(P<0.05)。B组顶椎置入的41枚螺钉中,有5枚为不良置钉(12.2%)。结论:对于Cobb角在50°～70°非严重的Lenke 1型青少年特发性脊柱侧凸,顶椎置钉尽管并不能显著提高侧凸矫正率,但可以明显矫正顶椎旋转,因此,在注意置钉安全性的前提下,应尽量在顶椎置入椎弓根螺钉。     

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.     

Percutaneous minimally invasive instrumentation for traumatic thoracic and lumbar fractures: a prospective analysis

Open posterior instrumentation is still the standard procedure for unstable traumatic thoracic and lumbar fractures. There is a general tendency towards minimally invasive approaches in various surgical disciplines. The Sextant II Rod Insertion system is one of these. The authors prospectively studied this system in 51 patients with thoracic and lumbar fractures, between October 2007 and January 2011. Most fractures (31/51) were situated at the lumbar level. In 7 older patients the technique was combined with kyphoplasty and/or cement augmentation of the pedicle screws. The median operative time was 61 minutes (range: 26-130). The median fluoroscopy time was 132 seconds (range: 24-414). Most pedicle screws were correctly placed: 197 out of 204 screws. All fractures showed bony union after 6 weeks, but the multiaxial pedicle screws were not able to conserve the slight correction obtained peroperatively via positioning and longitudinal traction. Percutaneous minimally invasive stabilization of the spine needs further improvement.     

经皮椎弓根螺钉内固定治疗胸腰椎骨折的生物力学及临床研究

 目的 通过生物力学测试及临床应用对经皮跨伤椎四钉内固定(万向钉固定)与开放手术四钉内固定(单向钉固定)进行比较。方法 取 12具新鲜冰冻小牛腰椎标本 L1~L5节段,随机分为单向钉固定组与万向钉固定组。制备腰椎前中柱损伤模型,比较两组在模型上的运动范围。分别应用 Sextant经皮跨伤椎四钉内固定与开放跨伤椎四钉内固定治疗无神经功能损伤的胸腰椎骨折 25例和 35例,观察其中随访超过 12个月的 11例和 18例的即时复位效果、矫正度丢失情况。结果 (1)生物力学试验院万向钉固定组在各个方向的运动范围均大于单向钉固定组,其中在前屈、后伸方向的差异有统计学意义; 单向钉固定组在前屈、后伸、侧屈方向上的稳定性较完整标本大,差异有统计学意义; 万向钉固定组在前屈、后伸方向上的稳定性与完整标本比较差异无统计学意义。(2)临床应用院两组术前、术后伤椎前缘高度、矢状位 Cobb角的组间差异均无统计学意义; 两组术后伤椎前缘高度、矢状面 Cobb角与术前比较差异均有统计学意义; 末次随访时经皮跨伤椎四钉内固定组伤椎前缘高度丢失(9.9%±5.1%)大于开放跨伤椎四钉内固定组(5.3%±6.8%)。结论 应用 Sextant系统经皮椎弓根螺钉内固定治疗无须神经减压的胸腰椎骨折较开放手术创伤小,但随访中伤椎前缘高度丢失明显。生物力学试验显示其在前屈、后伸运动方向上的强度较弱。     

Evaluation des sagittalen Profils nach operativer Therapie der thorakalen adoleszenten idiopathischen Skoliose Lenke Typ 1

Introduction

The principle philosophy of posterior spinal instrumentation and fusion (PSIF) for the treatment of adolescent idiopathic scoliosis (AIS) has changed during recent decades. In the past the treatment of AIS mainly focused on correction of the major curve in the frontal plane while the sagittal profile and balancing were only of inferior interest in treatment planning. Various long-term outcome studies have demonstrated that many AIS patients developed a flatback syndrome (decrease of thoracic kyphosis and lumbar lordosis) associated with pain. It was concluded that treatment of AIS should consider the sagittal profile and balance; however, there are only few studies addressing additional procedures, which include the correction of the sagittal profile.

Material and methods

The purpose of this study was to evaluate the effects of different posterior correction techniques on sagittal profile and balance. A total of 36 consecutive patients with thoracic AIS, who were treated with selective thoracic posterior correction were included in this retrospective study. The patients were further assigned to three different subgroups according to different surgical strategies: A: pedicle screws, B: long-head pedicle screws and C: additional Ponte osteotomy. Standardized radiographs in the standing position of the whole spine in two planes were evaluated before and at least 2 years after correction for all patients and a subgroup analysis was done to identify differences between the three groups.

Results

A significant correction of the major curve was achieved in all three groups (p?<?0.001). There was a significant difference between the groups with groups B and C showing significantly higher levels of major curve correction in comparison to group A (p?<?0.001). Concerning the sagittal profile, there was a significant difference in the development of thoracic kyphosis (TK) and lumbar lordosis (LL). While a significant reduction of TK and LL was found in groups A and B after surgery, a significant increase of TK and LL was noted in group C which was associated with a decrease of pelvic tilt and an increase of sacral slope. The 2-year follow-up showed the lowest ODI-% value only in group C which was positively correlated with reduction in pelvic tilt.

Conclusions

The results of this study underline that the PSIF technique alone using pedicle screws leads to a satisfactory correction in the frontal plane but is associated with adverse effects on the sagittal profile (flat back syndrome), corroborating previous studies. It was further shown that significant improvements of sagittal parameters were achieved by adding techniques for the lengthening of the dorsal thoracic column. This approach can therefore be recommended for the treatment of AIS Lenke type 1.     

全节段与选择性节段椎弓根螺钉固定治疗重度僵硬型青少年特发性脊柱侧凸比较

目的 比较全节段椎弓根螺钉(all segmental pedicle screws,ASPS)固定与选择性节段椎弓根螺钉(selective segmental pedicle screws,SSPS)固定治疗重度僵硬型青少年特发性脊柱侧凸(adoles-cent idiopathic scoliosis,AIS)的疗效.方法 回顾性分析我院2003年3月至2008年12月期间单纯行后路椎弓根螺钉固定融合治疗的重度僵硬型AIS患者.站立前后位主胸弯Cobb角>70°和柔韧度<30%者为筛选对象,从327例AIS患者中筛选出符合标准的48例,22例行SSPS同定,26例行ASPS固定.统计并比较两组患者手术时的年龄、术前冠状面主胸弯Cobb角、脊柞柔韧度、术中出血量、术后1周及末次随访时的矫正率.结果 ASPS组和SSPS组的平均年龄分别为15.65岁和17.32岁,术前冠状面主胸弯Cobb角分别为86.77°±11.71°(71.31°～107.51°)和87.56°±14.88°(70.10°～117.83°),柔韧度分别为15.82%±7.37%(6.82%～29.74%)和19.30%±9.19%(0.89%～29.71%),手术时间分别为(280.69±35.92)min和(275.10±33.91)min,术中出血量分别为(988.50±287.80)ml和(800.98±360.47)ml(t=2.004,P=0.051),术后1周冠状面主胸弯畸形矫正率分别为60.07%±8.80%和46.79%±14.90%(u=3.280,P=0.001).ASPS组有1例因凸侧断棒而明显丢失畸形矫正率,余患者无明显丢失.结论 对于重度僵硬型AIS,ASPS治疗的患者术后冠状面主胸弯矫正率明显高于SSPS治疗的患者.     

Correction of adolescent idiopathic scoliosis using thoracic pedicle screw fixation versus hook constructs

This retrospective study was undertaken to determine the effectiveness and cost of thoracic pedicle screws versus laminar and pedicle hooks in patients undergoing surgical correction of adolescent idiopathic scoliosis (AIS). Immediate preoperative and 6-week postoperative radiographs were examined in 25 consecutive cases of children with AIS who were divided into two groups, those with thoracic pedicle screw constructs and those with thoracic hook constructs. Endpoints collected included radiographic measures, complications, surgical time, implant cost, and quality-of-life measures. Ten children underwent spinal fusion using thoracic pedicle screw fixation and 15 underwent thoracic constructs composed of hooks. Similar sex and age distribution were noted in both groups, and among the 20 girls and 5 boys the average age was 14.5. The mean preoperative Cobb angle was 53.5 degrees for the screw group and 52.5 degrees for the hook group. Correction averaged 70.2% for the screw group and 68.1% for the hook group. There were no significant differences between the two patient groups in terms of percentage of or absolute curve change after surgery. The apical vertebral translation, end vertebral tilt angle, and coronal balance did not differ significantly between the two patient groups. Comparison of operative time and quality of life revealed no significant differences. Screw constructs were significantly more expensive than hook constructs. The correction obtained from thoracic pedicle screw fixation is comparable to traditional hook constructs in AIS. Surgery using either construct effectively corrects AIS.     

Coronal deformity correction in adolescent idiopathic scoliosis patients using the fulcrum-bending radiograph: a prospective comparative analysis of the proximal thoracic, main thoracic, and thoracolumbar/lumbar curves

The aim of the prospective, comparative radiographic analysis was to determine the role of the fulcrum-bending radiograph (FBR) for the assessment of the proximal thoracic (PT), main thoracic (MT), and the thoracolumbar/lumbar (TL/L) curves in patients undergoing posterior spinal pedicle screw fixation and fusion for adolescent idiopathic scoliosis (AIS). The FBR demonstrated statistically better correction than other preoperative methods for the assessment of frontal plane correction of the MT curves. The fulcrum-bending correction index (FBCI) has been considered a superior method than the correction rate for comparing curve correction undergoing posterior spinal fusion because it accounts for the curve flexibility. However, their applicability to assess the PT and TL/L curves in AIS patients remains speculative. The relation between FBR and correction obtained by pedicle screws fixation is still unknown. Thirty-eight consecutive AIS patients who underwent pedicle screw fixation and posterior fusion were included in this study. The assessment of preoperative radiographs included standing posterior–anterior (PA), FBR, supine side-bending, and postoperative standing PA and lateral plain radiographs. The flexibility of the curve, as well as the FBCI, was calculated for all patients. Postoperatively, radiographs were assessed at immediate (i.e. 1 week), 3-month, 6-month, 12-month, and 2-year follow-up. Cobb angles were obtained from the PT, MT, and TL/L curves. The study consisted of 9 PT, 37 MT, and 12 TL/L curves, with a mean age of 15.1 years. The mean FBR flexibility of the PT, MT, and the TL/L curves was 42.6, 61.1, and 66.2%, respectively. The mean operative correction rates in the PT, MT, and TL/L curves were 43.4, 69.3, and 73.9%, respectively, and the mean FBCI was 103.8, 117.0, and 114.8%, respectively. Fulcrum-bending flexibility was positively correlated with the operative correction rate in PT, MT, and TL/L curves. Although the correction rate in MT and TL/L curves was higher than PT curves, the FBCI in PT, MT, and TL/L curves was not significantly different (p < 0.05). The FBR can be used to assist in the assessment of PT, MT, and TL/L curve corrections in AIS patients. When curve flexibility is taken into account by FBR, the ability of pedicle screws to correct PT, MT, and TL/L curves is the same.     

Comparison of intraoperative supine and postoperative standing radiographs after posterior instrumentation for adolescent idiopathic scoliosis

The utility of intraoperative radiographs after posterior spinal segmental instrumentation for adolescent idiopathic scoliosis (AIS) is debatable. A retrospective review of 74 patients with moderately severe AIS revealed the main thoracic Cobb measurements of 57° preoperatively, 17° intraoperatively, 18° on initial postoperative, and 20° on final postoperative radiographs. On the basis of the extent and type of instrumentation (pedicle screws vs. hybrid construct), there was no clinically significant difference in curve magnitude between intraoperative and postoperative radiographs. After posterior segmental instrumentation for moderate AIS, frontal plane correction measured on intraoperative supine radiographs are comparable with similar measurements made on full-length postoperative standing radiographs.