术中CT在后路全椎弓根螺钉治疗重度脊柱侧凸中的初步应用

目的:探讨术中CT在重度脊柱侧凸患者后路全椎弓根螺钉手术中的应用价值和临床疗效.方法:回顾性分析了2009年6月至201 1年6月行全椎弓根螺钉后路治疗的32例重度脊柱侧凸患者,其中男12例,女20例;年龄10～38岁,平均16.8岁;其中19例合并后凸.在术中椎弓根钉置钉完成后应用术中CT扫描多平面重建图像评估螺钉位置并分级,计算在上胸椎(T1-T4),中胸椎(T5-T8),下胸椎(T9-T12)和腰椎的螺钉评级结果及螺钉数目(比率),评估为2级和3级的螺钉为误置螺钉.计算术中应用CT次数.测量患者手术前后冠状面Cobb角及合并后凸病例手术前后矢状面后凸Cobb角,计算侧凸及后凸矫正率.结果:32例患者共置入胸腰椎螺钉686枚,其中胸椎螺钉544枚,腰椎螺钉142枚,其中14例患者行截骨手术.经术中CT评估分级,在上胸椎、中胸椎、下胸椎和腰椎的误置螺钉率分别是5.6％,11.1％,6.7％和4.3％,在胸腰椎总计是7.3％,误置螺钉在术中进行了修正.术中平均应用CT 2.6次(2～4次).术前侧凸Cobb角平均95°(78°～123°),术后侧凸Cobb角平均为34°(19°～53°),矫正率为64％;合并后凸病例术前后凸Cobb角69°(46°～82°),术后后凸Cobb角平均为32°(22°～45°),矫正率为54％.术后有4例患者脑脊液漏,未发现神经血管损伤病例及手术伤口感染病例.所有病例获得随访,时间12～26个月,平均18个月.未发现断钉、断棒、假关节形成等并发症发生.结论:在重度脊柱侧凸全椎弓根螺钉后路手术中应用术中CT可及时发现误置螺钉并进行修正,避免了因螺钉误置导致的二次手术,保障了手术安全,手术效果良好.     

Ponte截骨与SPO截骨联合后路全椎弓根螺钉系统矫正僵硬性青少年特发性胸椎侧凸的疗效比较

[目的]对Ponte截骨与Smith-Petersen截骨(SPO截骨)治疗僵硬性青少年特发性胸椎侧凸的临床疗效及影像学结果进行回顾性比较。[方法]2007年5月～2009年3间收治的单纯后路全椎弓根螺钉系统矫正僵硬性青少年特发性胸椎侧凸的手术病例58例,其中36例行SPO截骨,22例行Ponte截骨。通过影像学检查对两组的手术效果和躯干平衡情况进行分析,末次随访时用中文版SRS-22量表进行患者的健康生存质量评价。[结果]两组患者的性别比例、手术时年龄、Risser征、融合节段数、置钉密度、术前冠状面胸主弯Cobb角无显著性意义(P>0.05)。Ponte截骨组的术后3个月冠状面胸主弯Cobb角矫正率明显大于SPO截骨组,分别为67.1%和56%(P<0.05)。末次随访时两组矫正率得到很好的维持,分别为61%和50.5%(P<0.05)。两组的术前、术后腰椎代偿性次弯Cobb角无显著性差异。两组的术前胸椎后凸Cobb角分别为20.6±8.5°和22.3±10.5°,术后3个月胸椎后凸角SPO截骨组比术前平均增加1.2°,Ponte截骨组比术前平均丢失1.4°,末次随访SPO截骨组胸椎后凸角比术前平均增加1.9°,Pon-te截骨组比术前平均丢失2.9°,两组间比较无显著性差异(P>0.05)。两组的次要并发症无显著性差异(P>0.05),两组均未发生主要并发症。[结论]多节段Ponte截骨能提高僵硬性青少年特发性胸椎侧凸冠状面胸主弯Cobb角的手术矫正率,并不增加并发症的发生率,而且能提供更多的局部自体植骨量、增加植骨融合面积。     

Skip pedicle screw fixation combined with Ponte osteotomy for adolescent idiopathic scoliosis

Purpose

This study aimed to determine whether Ponte osteotomy combined with skip pedicle screw fixation (SPSF) can improve the correction rate and restore thoracic kyphosis for patients with adolescent idiopathic scoliosis.

Methods

Surgical time, blood loss, preoperative Cobb angle of the main thoracic curve, flexibility, Cobb angle at 1 year after surgery, thoracic curve correction rate, and Cincinnati correction index (CCI) were determined for both the Ponte (n = 17) and non-Ponte (control; n = 21) groups. Furthermore, kyphotic angles at T5–T12 before and 1 year after the surgery were measured.

Results

The following measurements were obtained for the Ponte and control groups, respectively: surgical time, 236 ± 13 and 187 ± 9 min; blood loss, 1,141 ± 150 and 745 ± 120 g; preoperative Cobb angle of the main thoracic curve, 52.5° ± 10.4° and 51.5° ± 9.2°; flexibility, 31.7 ± 13.2 and 45.1 ± 12.3 % (p = 0.003); thoracic curve correction rate, 62.0 ± 2.5 and 63.6 ± 2.5 %; CCI, 2.2 ± 0.2 and 1.5 ± 0.1 (p = 0.003); preoperative kyphotic angle at T5–T12, 11.3° ± 11.2° and 13.0° ± 9.0°; and kyphotic angle at T5–T12 at 1 year after the surgery, 21.8° ± 1.7° and 24.2° ± 1.9°.

Conclusion

Ponte osteotomy was combined with SPSF in case of rigid curve. CCI was significantly greater in the Ponte group. Postoperative thoracic kyphotic angles were identical in both groups.     

Segmental pedicle screw instrumentation in idiopathic thoracolumbar and lumbar scoliosis

The role of posterior correction and fusion in thoracolumbar and lumbar scoliosis as well as pedicle screw instrumentation in scoliosis surgery are matters of debate. Our hypothesis was that in lumbar and thoracolumbar scoliosis, segmental pedicle screw instrumentation is safe and enables a good frontal and sagittal plane correction with a fusion length comparable to anterior instrumentation. In a prospective clinical trial, 12 consecutive patients with idiopathic thoracolumbar or lumbar scolioses of between 40° and 60° Cobb angle underwent segmental pedicle screw instrumentation. Minimum follow-up was 4 years (range 48– 60 months). Fusion length was defined according to the rules for Zielke instrumentation, normally ranging between the end vertebrae of the major curve. Radiometric analysis included coronal and sagittal plane correction. Additionally, the accuracy of pedicle screw placement was measured by use of postoperative computed tomographic scans. Major curve correction averaged 64.6%, with a loss of correction of 3°. The tilt angle was corrected by 67.0%, the compensatory thoracic curve corrected spontaneously according to the flexibility on the preoperative bending films, and led to a satisfactory frontal balance in all cases. Average fusion length was the same as that of the major curve. Pathological thoracolumbar kyphosis was completely corrected in all but one case. One patient required surgical revision with extension of the fusion to the midthoracic spine due to a painful junctional kyphosis. Eighty-five of 104 screws were graded “within the pedicle”, 10 screws had penetrated laterally, 5 screws bilaterally and 4 screws medially. No neurological complications were noted. In conclusion, despite the limited number of patients, this study shows that segmental pedicle screw instrumentation is a safe and effective procedure in the surgical correction of both frontal and sagittal plane deformity in thoracolumbar and lumbar scoliosis of less than 60°, with a short fusion length, comparable to anterior fusion techniques, and minimal loss of correction. Received: 23 September 1999 Revised: 20 January 2000 Accepted: 26 January 2000     

Thoracic pedicle screw insertion in scoliosis using posteroanterior C-arm rotation method

OBJECTIVE: Previous researches have emphasized the importance and difficulties in accurate thoracic pedicle screw insertion in scoliosis patients. However, there has been no report on accuracy of the insertion using posteroanterior C-arm fluoroscopy rotated to allow en face visualization of the pedicle in humans. This study aimed to evaluate the accuracy of the thoracic pedicle screw insertion technique using a C-arm fluoroscopy rotation method for the treatment of scoliosis. METHODS: Between October 1997 and September 2005, 33 scoliosis patients who underwent surgical treatment with a total of 410 screws were analyzed. Eleven were male, 22 female and the mean age was 13.4 years. The mean preoperative Cobb angle was 59.7 degrees. Screws were inserted using the C-arm rotation method; screw positions were evaluated with postoperative computed tomography scans. RESULTS: The mean preoperative Cobb angle of 59.7 degrees was corrected to 18.9 degrees (range, 3 to 45 degrees) in the coronal plane (mean correction rate 68%). Postoperative computed tomography scans demonstrated 48 screws penetrated the medial (9 screws) or lateral (39 screws) pedicle cortex with a mean distance of 3.1 and 3.6 mm, respectively. No screws penetrated the inferior or superior cortex in the sagittal plane. CONCLUSIONS: Thoracic pedicle screw insertion in scoliosis patients using the posteroanterior C-arm rotation method allows en face visualization of both pedicles by rotating the C-arm to compensate for the rotational deformity, making it a practical, simple and safe method.     

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。     

Factors influencing the residual rib hump after posterior spinal fusion for adolescent idiopathic scoliosis with Lenke 1 and 2 curves

Background

Despite remarkable improvement in Cobb angle after surgery for scoliosis, many patients have a residual rib hump. We studied the factors responsible for this hump and their influence on patient satisfaction.

Methods

We recruited 2 men and 38 women (mean age 14.9 years) who underwent skip pedicle screw fixation combined with direct vertebral body derotation for adolescent idiopathic scoliosis with Lenke type 1 and 2 curves. Hump size was evaluated by measuring apical trunk rotation (ATR). Patients with postoperative ATR ≤10° were categorized as group A and those with postoperative ATR >10° as group B. We analyzed postoperative self-image and satisfaction subscores of the SRS-22 questionnaire. We also compared the rate of postoperative improvement in ATR between patients who underwent additional Ponte osteotomy and those who did not.

Results

Preoperative ATR, preoperative apical translation, and preoperative and postoperative apical rotation significantly differed between groups A and B. In contrast, Cobb angles before and after surgery, Cobb angle correction rates, apical translation after correction, and postoperative self-image and satisfaction scores did not differ significantly between the groups. However, the rate of improvement in ATR showed a strong correlation with self-image (correlation coefficient 0.64) and satisfaction (correlation coefficient 0.52). This improvement rate did not differ significantly between subjects who underwent additional Ponte osteotomy and those who did not.

Conclusions

Preoperative apical rotation and ATR were clearly related to postoperative residual hump. For decreasing the postoperative rib hump, removal of the deformation by apical rotation was considered more important than correction of Cobb angle. Patient satisfaction and self-image scores were not significantly related to postoperative residual hump size, but they were influenced by improvement in ATR.     

Thoracic curve correction after posterior fusion and instrumentation of structural lumbar curves in patients with adolescent idiopathic scoliosis

Introduction

Spontaneous thoracic curve correction may occur following selective anterior spinal fusion in patients with adolescent idiopathic scoliosis (AIS). However, a few reports have described outcomes in patients following selective posterior fusion. The aim of this retrospective study was to assess curve correction in AIS patients with major lumbar curves and secondary thoracic curves after selective posterior fusion of the major curve.

Methods

The records of 42 AIS patients with major lumbar and minor thoracic curves who had received selective posterior lumbar fusion with segmental pedicle screw fixation were examined. Preoperative and follow-up radiographs were examined and the following were determined: curve flexibility, Cobb angle measurements of the major and minor curves, thoracolumbar/lumbar and thoracic Cobb measurements. Also, thoracolumbar/lumbar to thoracic Cobb ratios were determined. Minimum follow-up was 2?years. Patients were compared with respect to whether final thoracic curve improvement was (group A) or was not (group B) apparent. Improvement was indicated by a final thoracic curve that was less than the preoperative thoracic curve.

Results

Thoracic curve improvement was apparent in 32 of 42 patients after surgery. The mean preoperative thoracic curve in group A was 22.5° and 15.0° at follow-up, while corresponding values in group B were 35.0° and 39.8°. There were no cases in group A and eight cases in group B in which the preoperative thoracic curve was >30°. All patients in group B had preoperative thoracic curves on lateral bending >20°. Thoracic curvature at final follow-up was strongly correlated with preoperative thoracic curvature (r?=?0.911) and thoracic curvature on lateral bending (r?=?0.948).

Conclusions

Selective posterior fusion with segmental pedicle screw fixation in patients with major lumbar AIS resulted in curve correction in the majority of cases. Preoperative thoracic curvature and thoracic curvature on lateral bending were strongly correlated with the final thoracic curvature.     

Dorsale operative Korrektur der idiopathischen Skoliose

Posterior correction and fusion of scoliosis with multisegmental instrumentation systems was developed by Cotrel-Dubousset in the 1980s. Initially correction and instrumentation was performed using hooks only. Later pedicle screws were implemented first for the lumbar and then for the thoracic spine. Nowadays instrumentation based on pedicle screws only is well established for posterior scoliosis surgery. Biomechanical studies demonstrated higher pull-out forces for pedicle than for hook constructs. In clinical studies several authors reported better Cobb angle correction of the primary and the secondary curves and less loss of correction in pedicle screw versus hook instrumentations. Furthermore, pedicle screw instrumentation allows fewer segments to be fused, especially caudally, and thus saving mobile segments. In most of these publications there were no differences in operation time, blood loss and complication rates. In summary, there is better curve correction without an increased risk using multisegmental pedicle screw instrumentation in modern posterior scoliosis surgery.     

Treatment and complications in flaccid neuromuscular scoliosis (Duchenne muscular dystrophy and spinal muscular atrophy) with posterior-only pedicle screw instrumentation

Literature has described treatment of flaccid neuromuscular scoliosis using different instrumentation; however, only one article has been published using posterior-only pedicle screw fixation. Complications using pedicle screws in paralytic neuromuscular scoliosis has not been described before. To present results and complications with posterior-only pedicle screws, a retrospective study was carried out in 27 consecutive patients with flaccid neuromuscular scoliosis (Duchenne muscular dystrophy and spinal muscular atrophy), who were operated between 2002 and 2006 using posterior-only pedicle screw instrumentation. Immediate postoperative and final follow-up results were compared using t test for Cobb angle, pelvic obliquity, thoracic kyphosis and lumbar lordosis. Perioperative and postoperative complications were noted from the hospital records of each patient. Complications, not described in literature, were discussed in detail. Average follow-up was 32.2 months. Preoperative, immediate postoperative and final follow-up Cobb angle were 79.8°, 30.2° (63.3% correction, p < 0.0001) and 31.9°, respectively; and pelvic obliquity was 18.3°, 8.9° (52% correction, p < 0.0001) and 8.9°. Postoperative thoracic kyphosis remained unchanged from 27.6° to 19.9° (p = 0.376); while lumbar lordosis improved significantly from +15.6° to −22.4° lordosis (p = 0.0002). Most patients had major to moderate improvement in postoperative functional and ambulatory status compared to the preoperative status. Thirteen (48.1%) perioperative complications were noted with five major complications (four respiratory in the form of hemothorax or respiratory failure that required ventilator support and one death) and eight minor complications (three UTI, two atelectasis, two neurological and one ileus). Postoperatively, we noted complications, such as coccygodynia with subluxation in 7, back sore on the convex side in 4 and dislodging of rod distally in 1 patient making a total of 12 (44.4%) postoperative complications. Of 12 postoperative complications, 6 (50%) required secondary procedure. We conclude that although flaccid neuromuscular scoliosis can be well corrected with posterior-only pedicle screw, there is a high rate of associated complications.     

特发性脊柱侧凸多节段Ponte截骨术对恢复胸椎后凸的疗效

目的探讨在特发性脊柱侧凸(idiopathic scoliosis,IS)后路矫形手术中,多节段Ponte截骨术对保持和恢复胸椎后凸的作用。方法回顾分析2008年3月-2010年2月收治的42例采用脊柱后路椎弓根钉棒系统矫治的Lenke 1型IS患者,按照术中脊柱后方结构松解方式不同分为A、B两组。A组17例采用多节段Ponte截骨术,截骨部位均选择在胸弯顶椎附近连续3个节段;B组25例采用单纯软组织松解术。两组患者性别、年龄、病程、病变累及节段、冠状面Cobb角、胸椎后凸角、Risser指数及侧方弯曲像柔韧度比较差异均无统计学意义(P>0.05),具有可比性。手术前后摄脊柱站立正侧位X线片并记录相关临床资料,比较两组手术效果。结果所有手术均顺利完成。A组手术时间和术中失血量均显著大于B组,差异有统计学意义(P<0.05)。A组术中1例发生硬膜损伤、脑脊液漏,术后俯卧、切口加压后自行愈合;其余患者均未发生术中相关并发症。所有患者均获随访,随访时间2～4年,平均2.8年。均无神经损伤、感染和内固定失败等并发症发生。术后无明显矫形丢失,外观和躯干平衡均明显改善。A、B组术后1周及2年主胸弯冠状面Cobb角均较术前明显改善(P<0.05);术后1周及2年间比较差异无统计学意义(P>0.05)。A组术后1周及2年冠状面Cobb角及矫正率与B组比较差异无统计学意义(P>0.05)。A组术后1周及2年的胸椎后凸角及角度改变均优于B组,差异有统计学意义(P<0.05)。结论在Lenke 1型IS后路矫形手术中,通过多节段Ponte截骨术,在矢状面能够有效保持和恢复胸椎后凸,在冠状面对矫正率无明显影响。     

新型滑槽钉生长棒内固定系统治疗儿童脊柱侧凸的初步报告

 目的 评价新型滑槽钉生长棒内固定系统在儿童脊柱侧凸治疗中的初步临床疗效。 方法 自2009年1月至2011年7月,使用滑槽钉生长棒内固定系统治疗脊柱侧凸患儿10例,男3例,女7例;年龄4～12岁,平均7.8岁。Risser征均为0级。均为特发性脊柱侧凸。单胸弯3例,单胸腰弯或腰弯6例,双胸弯1例。入院时冠状位Cobb角38°~85°,平均66.8°;矢状位Cobb角38°~66°,平均45.5°;坐高36~64 cm,平均48.6 cm。疗效评价指标包括冠状位、矢状位Cobb角及其矫正率、坐高、躯干偏移、双肩高度差、植骨融合情况、矫正丢失率和并发症,重点在身高和发育情况。结果 术后即刻冠状位Cobb角17°~39°,平均28°,矫正率为48%～65%,平均为52%。术后矢状位Cobb角25°~39°,平均31°,坐高46~70 cm,平均56.8 cm。全部病例随访12～44个月,平均26.5个月。随访期间矫正角度丢失率＜ 5%,坐高平均增加2 cm ,3例出现矫形棒尾端皮肤感染,均予以局部换药后痊愈,1例术后出现肩部失平衡,余未出现断钉、断棒等内固定相关并发症。结论 新型滑槽钉生长棒内固定系统治疗儿童脊柱侧凸的初步临床疗效证实该系统的有效性和安全性。     

Mid-term results of computer-assisted skip pedicle screw fixation for patients with Lenke type 1 and 2 adolescent idiopathic scoliosis: A minimum five-year follow-up study

Purpose

In skip pedicle screw fixation for adolescent idiopathic scoliosis (AIS), the mid-term effects of reducing screw number on correction and clinical results are uncertain. We clarified the mid-term outcomes of this technique in patients with Lenke type 1 and 2 AIS.

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。     

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.     

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.     

Anterior dual rod instrumentation in idiopathic thoracic scoliosis

For anterior correction and instrumentation of thoracic curves single rod techniques are widely used. Disadvantages of this technique include screw pullouts, rod fractures and limited control of kyphosis. This is a prospective study of 23 consecutive patients with idiopathic thoracic scoliosis treated with a new anterior dual rod system. Aim of the study was to evaluate the safety and efficacy of this new technique in the surgical treatment of idiopathic thoracic scoliosis. To the best knowledge of the authors, this is the largest series on dual rod dual screw instrumentation over the entire fusion length in thoracic scoliosis. Twenty-three patients with an average age of 15 years were surgically treated with a new anterior dual rod system through a standard open double thoracotomy approach. Average clinical and radiological follow-up was 28 months (24–46 months). Fusion was carried out mostly from end-to-end vertebra. The primary curve was corrected from 66.6° to 28.3° (57.5% correction) with an average loss of correction of 2.0° at Cobb levels and of 1.3° at fusion levels. Spontaneous correction of the secondary lumbar curve averaged 43.2% (preoperative Cobb angle 41.2°). The apical vertebral rotation was corrected by 41.1% with a consecutive correction of the rib hump of clinically 66.7%. The thoracic kyphosis measured 29.2° preoperatively and 33.6° at follow-up. In seven patients with a preoperative hyperkyphosis of on average 47.3° thoracic kyphosis was corrected to 41.0°. This new instrumentation enables an entire dual rod instrumentation over the whole thoracic fusion length. It offers primary stability without the need of postoperative bracing. Dual screw dual rod instrumentation offers the advantages of a high screw pullout resistance, an increased overall stability and satisfactory sagittal plane control.     

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.     

Comparative analysis of pedicle screw and hook instrumentation in posterior correction and fusion of idiopathic thoracic scoliosis

Posterior correction and fusion with segmental hook instrumentation represent the gold standard in the surgical treatment of progressive idiopathic thoracic scoliosis. However, there is a debate over whether pedicle screws are safe in scoliosis surgery and whether their usage might enable a better curve correction and a shorter fusion length. The details of curve correction, fusion length and complication rate of 99 patients with idiopathic thoracic scoliosis treated with either hook or pedicle screw instrumentation were analyzed. Forty-nine patients had been operated with the Cotrel-Dubousset system using hooks exclusively ("hook group"). Fifty patients had been operated with either a combination of pedicle screws in the lumbar and lower thoracic and hooks in the upper thoracic spine or exclusive pedicle screw instrumentation using the Münster Posterior Double Rod System ("screw group"). The preoperative Cobb angle averaged 61.3 degrees (range 40 degrees-84 degrees ) in the hook group and 62.5 degrees (range 43 degrees-94 degrees ) in the screw group. Average primary curve correction was 51.7% in the hook group and 55.8% in the screw group ( P>0.05). However, at follow-up (2-12 years later) primary curve correction was significantly greater ( P=0.001) in the screw group (at 50.1%) compared to the hook group (at 41.1%). Secondary lumbar curve correction was significantly greater ( P=0.04) in the screw group (54.9%) compared to the hook group (46.9%). Correction of the apical vertebral rotation according to Perdriolle was minimal in both groups. Apical vertebral translation was corrected by 42.0% in the hook group and 55.6% in the screw group ( P=0.008). Correction of the tilt of the lowest instrumented vertebra averaged 48.1% in the hook group and 66.2% in the screw group ( P=0.0004). There were no differences concerning correction of the sagittal plane deformity between the two groups. Fusion length was, on average, 0.6 segments shorter in the screw group compared to the hook group ( P=0.03). With pedicle screws, the lowest instrumented vertebra was usually one below the lower end vertebra, whereas in the hook group it was between one and two vertebrae below the lower end vertebra. Both operative time and intraoperative blood loss were significantly higher in the hook group ( P<0.0001). One pedicle screw at T5 was exchanged due to the direct proximity to the aorta. There were no neurologic complications related to pedicle screw instrumentation. Pedicle screw instrumentation alone or in combination with proximal hook instrumentation offers a significantly better primary and secondary curve correction in idiopathic thoracic scoliosis and enables a significantly shorter fusion length.