Efficacy of perioperative halo-gravity traction for treatment of severe scoliosis (≥100°)

Background

There have been no standardized surgical options for severe scoliotic curvatures ≥100°. Halo-gravity traction is a viable option for surgical treatment of severe scoliosis. The aim of this study was to evaluate the efficacy and safety of perioperative halo-gravity traction for scoliosis curves ≥100° with respect to radiographic outcomes and clinical complications.

Methods

A total of 21 scoliosis patients with ≥100° curves (average 118.7°; range 100°-158°) with a minimum 2-year follow-up (average 41.8 months; range 24.0-97.0 months) who underwent spinal instrumented fusion using perioperative halo-gravity traction were analyzed. Diagnoses were neuromuscular scoliosis (n = 10), idiopathic (n = 9), and congenital (n = 2). In all, 15 patients were treated by the anterior release procedure followed by final posterior fusion and 6 patients by posterior fusion alone. Six patients had only preoperative traction preceding posterior fusion alone, 6 patients only staged traction between anterior release and final posterior fusion, and 9 patients had both preoperative traction preceding anterior release and staged traction preceding final posterior fusion. The average overall traction period in all patients was 67 days (range 10–78 days).

Results

Radiographic outcomes demonstrated 51.3% correction of the major Cobb angle, 40 mm correction of apical vertebral translation, 76 mm increase of T1-S1 length, and 20.7% increase of space available for lungs at the ultimate follow-up (all comparisons P < 0.05). Preoperative traction demonstrated 27.5% correction of the major curve Cobb angle, 51.5 mm increase of T1-S1 length, 14.9% increase of space available for the lungs (all comparisons P < 0.05). Staged traction after anterior release demonstrated 37.2% correction of the major curve Cobb angle, 26.1 mm correction of apical vertebral translation, 56.5 mm increase of T1-S1 length, 14.2% increase of space available for the lungs (all comparisons P < 0.05). There were only two patients with a pin-site problem, and one required débridement. There were no neurological deficits or clinical complications.

Conclusions

Scoliosis patients with ≥100° curves can be managed successfully by corrective fusion surgery concomitant with perioperative halo-gravity traction without significant complications.     

重度脊柱侧凸治疗中神经并发症的防治对策

目的探讨重度脊柱侧凸手术治疗中神经系统并发症的防治方法。方法手术治疗Cobb角大于80°的脊柱侧凸患者71例。术前侧凸角平均96．6°（80°～135°）,31例患者同时有脊柱后凸,平均后凸角83．0°（52°～145°）。行后路节段椎弓根螺钉固定14例,后路顶椎楔形截骨21例,分期手术34例,前后路联合手术2例。术中应用SEP和唤醒试验双向监测61例,单独唤醒试验10例。结果术后平均侧凸角39．6°（矫正率59．2％）,平均后凸角31．9°（矫正率61．6％）。39例患者术后平均随访51个月（5～81个月）,其中33例患者植骨融合良好,矫正丢失率平均2．1％,2例因内固定断裂再次手术。术前有神经功能障碍的8例患者中,除4例脊髓灰质炎后遗症外,3例完全恢复,1例大部分恢复。术后出现神经功能障碍5例,4例完全恢复,1例部分恢复。结论头颅骨盆环和脊椎截骨技术是提高重度脊柱侧凸矫正率、降低神经并发症的有效方法;术中唤醒试验配合SEP监测能较早提示神经系统损伤;对出现神经系统损伤患者,术后早期使用脱水药和激素有利于神经功能恢复。     

重度脊柱双侧凸的前后路手术治疗

目的: 通过前后路二次手术治疗重度脊柱双侧凸, 评价其治疗效果。方法: 1999年12月至今, 16例重度双侧凸患者, 采用前后路两次手术矫形, 矫正其在冠状面和矢状面的畸形。结果: 16例病例通过手术矫形, 胸段侧凸矫正率79%, 腰段83%, 腰椎后凸恢复成生理前凸, 椎体旋转度提高Ⅱ~Ⅲ度。结论: 通过前后路分次手术矫形, 可以对严重的、复杂的畸形进行有效的矫正, 彻底改变严重畸形的外观, 达到了良好的手术效果。     

Combined anterior and posterior instrumentation in severe and rigid idiopathic scoliosis

A prospective clinical and radiographic evaluation of 33 consecutive patients with severe and rigid idiopathic scoliosis (average Cobb angle 93°, flexibility on bending films 23%) were treated with combined anterior and posterior instrumentation with a minimum follow-up of 2 years. All patients underwent anterior release and VDS-Zielke Instrumentation of the primary curve. In highly rigid scoliosis, this was preceded by a posterior release. Finally, posterior correction and fusion with a multiple hook and pedicle screw construct was performed. Thirty patients were operated in one stage, three patients in two stages. Preoperative curves ranged from 80 to 122° Cobb angle. Frontal plane correction of the primary curve averaged 67% with an average loss of correction of 2°. The apical vertebral rotation of the primary curve was corrected by 49%. In all but three patients, sagittal alignment was restored. There were no neurological complications, deep wound infections or pseudarthrosis. Combined anterior and posterior instrumentation is safe and enables an effective three-dimensional curve correction in severe and rigid idiopathic scoliosis.     

Multiple vertebral osteotomies in the treatment of rigid adult spine deformities

STUDY DESIGN: Retrospective review of the clinical and radiographic results in adult revision spine deformity surgery using the techniques of osteotomies to effect spine balance and curve correction. OBJECTIVES: To assess the efficacy of multiple vertebral osteotomies in correction of rigid spine deformities in adult patients undergoing revision surgery. METHOD: The records and radiographs of 27 adult patients with idiopathic scoliosis who underwent revision surgery requiring anterior release (discectomy and/or osteotomy) and posterior osteotomy to correct rigid spinal deformities were retrospectively reviewed. RESULTS: All 27 patients were available for follow-up evaluation. Fifteen patients had anterior discectomies followed by posterior osteotomies, whereas 12 had anterior and posterior osteotomies in staged or sequential (same day) fashion. Diagnosis was idiopathic scoliosis for the index operation. At revision, the primary deformity was flatback deformity in 10 patients and pseudarthrosis with progressive deformity in 17 patients. Eleven patients had predominant sagittal decompensation, 11 patients had multiplanar decompensation, and five patients were balanced. The average number of osteotomies performed anteriorly was 4.3 levels (range, 1-8) and the average number of osteotomies posteriorly was 4.6 levels (range, 1-10). There were a total of nine complications in eight patients including three pseudarthroses (11%), five hardware failures (19%), and one transient neurologic deficit (4%). There were no deep wound infections, deep vein thromboses, pulmonary emboli, or deaths. The average scoliosis correction was 40% (range, 5-81%), whereas the average sagittal balance was corrected 6.5 cm (range, -5-29.5 cm), on average, and coronal balance was corrected 2.5 cm (range, 1-6 cm), on average. CONCLUSION: This study demonstrates multiple vertebral osteotomies (anterior and/or posterior) in the management of rigid adult spine deformities and deformity correction with an acceptable complication rate. Use of vertebral osteotomies for patients undergoing revision spine surgery is a safe and reasonable approach to obtain an arthrodesis.     

The variability of response of scoliotic spines to segmental spinal instrumentation.

Ninety-two patients (71 idiopathic, 15 neurogenic, 2 Marfan's syndrome, 1 Down's syndrome, 1 osteogenesis imperfecta, 1 Prader-Willi syndrome, 1 Klippel-Trenaunay-Weber syndrome), ages 9-49 years, had posterior spine fusion and stabilization with Luque L-rods and sublaminar segmental wires (SSI) for progressive scoliosis. There were no neurologic complications. The average preoperative major curve of 52 degrees (37-113 degrees) initially corrected to 30 degrees (6-94 degrees), and at last follow-up (range, 2-7 years), was 33 degrees (8-90 degrees). There was marked variability in curvature correction and maintenance of correction, with 14 patients progressively decreasing their curvatures postoperatively. Average preoperative Pedriolle vertebral rotation angle for all 92 patients was 16 degrees (4-26 degrees), which initially corrected to 14 degrees (0-24 degrees), and at last follow-up remained 14 degrees (0-23 degrees). Although SSI had little influence on rotation, 12 patients progressively decreased their rotational deformity after operation. Aside from the positive influence of curve flexibility on the degree of postoperative curve correction, the authors could not identify factors explaining how curvature and vertebral rotation responded so variably to SSI. The authors recommend continued use of SSI to stabilize curvatures in osteopenic patients (particularly those with neuromuscular disease), but rotational deformity will probably persist.     

Surgical treatment of idiopathic scoliosis with anterior dual rod instrumentation

BACKGROUND: In the surgical treatment of idiopathic scoliosis both anterior and posterior correction and instrumentation techniques are available. The aim of the present study was to analyse the results of a new anterior dual rod instrumentation. PATIENTS AND METHODS: Prospective analysis of radiometric and clinical parameters of 93 patients operated on between 1996 and 2004 using the Münster Anterior Dual Rod System. RESULTS: The average curve correction was 65% (fusion length usually Cobb levels) with a preoperative Cobb angle of 59 degrees. Postoperative loss of correction amounted to 1.5 degrees (average follow-up of 36 months). Apical vertebral derotation averaged 45% in the thoracic and 53% in the lumbar spine with a subsequent correction of the rib hump of 66% and the lumbar hump of 81%. There were no revisions or neurological complications. CONCLUSION: Anterior dual rod instrumentation enables an effective and safe three-dimensional curve correction in single structural curves with only minimal loss of correction.     

Surgical management of paralytic scoliosis in myelomeningocele

A retrospective analysis of 54 patients with paralytic scoliosis due to myelomeningocele, who underwent surgical treatment, was performed. The aim of this study was to compare different surgical techniques and to identify clinical parameters influencing primary and midterm results. Three surgical techniques were used: 1) group I, posterior fusion/instrumentation; 2) group II, anterior fusion/no instrumentation combined with posterior fusion/instrumentation; and 3) group III, anterior and posterior fusion/instrumentation. Average age at surgery was 13.1 years. A preoperative scoliosis angle of 90 degrees [interquartile range (25th-75th percentile) (IQR), 76-106 degrees] was primarily reduced to 38 degrees (IQR, 30-50 degrees). At final follow-up (mean, 3.3 years), correction deteriorated to 44 degrees (IQR, 38-65 degrees). The group III procedure resulted in a better midterm correction of scoliosis compared with group I (P = 0.02). The extension of anterior fusion correlated with primary and midterm correction of scoliosis (P < 0.03). Patients with a thoracic level of paralysis had a higher relative loss of correction compared with patients with a lumbar level (P < 0.06). This finding can be attributed mostly to group I patients (P = 0.011). Hardware complications occurred in 16 patients (30%). Relative loss of correction among these patients was high (P < 0.01) and relative midterm correction low (P = 0.001). We recommend anterior and posterior fusion, each with instrumentation for the treatment of paralytic scoliosis in myelomeningocele. In patients with a thoracic level of paralysis, the two-stage procedure is mandatory to reduce the risk of hardware complications and subsequent major loss of correction.     

TSRH内固定治疗脊柱侧凸

目的　回顾性研究TSRH(TexasScottishRiteHospital)脊柱内固定系统在治疗脊柱侧凸的临床疗效。 方法　对 1998年 1月至 2 0 0 0年 12月手术治疗的 12 9例脊柱侧凸患者 ,总结其侧弯矫形、脊柱平衡、并发症及 3年以上的随访结果。根据手术方法不同 ,共分为 4组。A组 :单纯脊柱后路融合固定术 ;B组 :单纯脊柱前路融合固定术 ;C组 :分期前、后路融合固定术 ;D组 :Ⅰ期前、后路融合固定术。四组患者均应用TSRH内固定系统。手术时平均年龄 14 .2岁 (6～ 5 5岁 ) ,平均随访 34个月。结果　A组 :78例病人行单纯脊柱后路融合TSRH内固定 ,术后平均矫形率为6 3.4 %。随访 38个月 (2 4～ 5 0个月 ) ,平均矫形丢失 7°,矫形丢失率平均 9.5 %。本组并发症发生率为 12 .8% ,包括 3例脱钩 ,3例螺钉断裂 (共 6枚螺钉 ) ,1例术后侧弯失代偿 ,1例术后发生曲轴现象。B组 :2 2例患者行单纯脊柱前路融合、短节段TSRH内固定 ,平均矫形率为 74 .8%。平均随访 36个月 ,平均矫形率丢失 5 %。 2例发生一过性交感神经损伤。术后 6个月内均自然恢复。C组 :17例有 90°以上的侧弯 ,且Bending像上侧弯仍大于 7°的患者行前路松解 ,2～ 3周后再行后路融合TSRH内固定。本组平均手术时间 8.3h ,出血 935ml,输血 6 83ml,平均矫形 33.6°,矫     

One- or two-step instrumentation for thoracolumbar scoliosis due to myelomeningocele?

AIM: This investigation evaluates patients with MMC who underwent a two-stage anterior-posterior correction and stabilisation of thoracolumbar scoliosis due to myelomeningocele. The data were compared with the few reported series of one-stage versus two-stage surgery in the literature. METHOD: From 1.7.1992 to 30.6.1995, 11 consecutive patients with severe thoracolumbar scoliosis due to myelomenigocele were admitted at our hospital. The mean age at operation was 12 years nine months (range nine years nine to 14 years six months). All patients underwent a two-stage anterior and posterior spinal instrumentation. The patients were pre- and postoperatively evaluated. RESULTS: All patients were followed for a mean of 4 years 11 months (range 42 months to 88 months) from the time of the second stage procedure. Preoperatively the mean scoliosis angle was 82 degrees (range 55 degrees to 110 degrees ), this was reduced to a mean of 31 degrees (range 8 degrees - 70 degrees ), at final follow-up, the correction had deteriorated slightly to a mean of 35 degrees (range 12 degrees - 80 degrees ). No patient had increased neurological deficit or showed other major complications, i. e., infection, sepsis due to immunologic disorders at the time of the operation. CONCLUSION: We believe that with the two-stage anterior and posterior instrumentation an effective correction of the scoliosis can be achieved. Compared to other studies this report confirms the low morbidity rate and emphasise the good results of a two staged procedure.     

Combined staged anterior and posterior correction and fusion of the spine in scoliosis following poliomyelitis.

The problems with severe forms of scoliosis following poliomyelitis include the associated muscle imbalance, soft tissue contractures and pelvic obliquity. Such deformities militate against optimal correction and maintenance of that correction and their treatment is often marred by pseudarthroses. Seventeen patients with an average curve of 93 degrees have been treated and followed for up to 38 months. Preliminary traction was used in 8 patients, then a staged anterior and posterior correction and fusion was done, using Dwyer's instrumentation of the major curve in all and a Harrington rod to supplement the posterior fusion in eleven patients. With this technique the major curve was corrected by 80 per cent with an average 2 per cent loss over 18 months. No pseudarthroses were seen when the Harrington rod was used. Great care must be taken if halo-pelvic traction is to be used for patients with pelvic obliquity, for preliminary correction halo-femoral traction will often be adequate. In the more severe forms of paralytic scoliosis a combined staged anterior and posterior correction and fusion should be considered if the aim is maximal correction of the scoliosis and avoidance of pseudarthroses.     

脊柱截骨术治疗创伤僵硬性胸腰段后凸畸形的解剖与临床研究

目的探讨经椎弓根椎体楔形截骨术治疗创伤僵硬性胸腰段后凸畸形的安全性和有效性。方法解剖研究中将16具新鲜胸腰段脊柱标本按不同脊柱截骨术分为3组,A组：脊柱开放-闭合截骨术,B组：经椎弓根椎体楔形截骨术,C组：改良经椎弓根椎体楔形截骨术（截骨包括上位椎间盘后半部分）。测量截骨前后Cobb角的变化、椎体高度和椎体前缘高度的变化。临床研究中共26例患者,其中男性18例,女性8例,平均36岁。受伤至本次手术时间3个月～11年,平均25个月。入院前治疗包括非手术治疗9例,手术治疗17例。神经损伤程度按照Frankel分级：A级10例,B级2例,C级10例,D级2例,E级2例。本组病例均有不同程度的腰背部疼痛,VAS评分平均4．5分（2．5～6．0分）。后凸角20°～75°,平均35°。根据后凸角大小选择行后路经椎弓根椎体楔形截骨术或改良椎体楔形截骨术。结果解剖研究胸腰段标本中A组平均纠正（38．0±2．5）°,B组（36．0±3．6）°,C组（49．0±2．0）°。A组椎体高度平均增加（13．8±1．4）mm,椎体前缘增加（30．2±2．5）mm,而B、C组椎体高度平均短缩（2．8±0．8）mm和（3．8±0．7）mm,前缘增加（25．0±1．2）mm和（2．2±0．9）mm。临床研究患者均获随访,随访时间10个月～6年,平均12．5个月,患者获得满意减压和后凸畸形矫正,术后后凸角度平均为10．8°（0°～40°）,脊柱后凸畸形平均矫正24°。50％患者的神经功能得到了不同程度恢复,全瘫患者恢复率为30％,主要是感觉功能恢复,而不全瘫患者的恢复率为64．3％,感觉和运动功能均有恢复。腰背部疼痛有不同程度好转,VAS评分平均2．3分（1．0～3．5分）。结论创伤僵硬性胸腰段后凸畸形患者可以选择经椎弓根椎体楔形截骨术或改良经椎弓根椎体楔形截骨术。术后可获得满意的减压效果和后凸畸形纠正,神经功能有不同程度恢复,腰背部疼痛有不同程度好转。     

经前路松解联合后路固定治疗特发性脊柱侧凸

目的:评价经前路松解联合后路矫形对特发性脊柱侧凸的治疗效果。方法:回顾性分析我院收治的51例(男16例,女35例;年龄8～17岁,平均13.2岁)特发性脊柱侧凸行前路松解及后路脊柱畸形矫形植骨融合术患者的临床资料及治疗结果。结果:本组中行前路松解、植骨,阻滞椎间盘平均2.4个。联合后路椎弓根钉(钩)-棒系统内固定,植骨、融合。术后特发性脊柱侧凸Cobb角<90°者额状平面平均矫正率为57%,矢状面后凸平均矫正率为50%;Cobb角>90°者额状平面平均矫正率为71%,矢状面后凸平均矫正率为74%。术后随访10～35个月,平均随访21.6个月,无矫正度的丢失及其他神经系统及血管损伤并发症。结论:脊柱前路松解安全、有效,联合后路相适应内固定系统矫形、植骨治疗特发性脊柱侧凸可获得满意治疗效果。     

Vertebral column resection and arthrodesis for complex spinal deformities.

Sixteen patients aged 13 to 55 with severe rigid spine deformities were treated by two-stage anterior and posterior vertebral column resection, fusion, and segmental spinal instrumentation. The purpose of the vertebral column resection was to eliminate pain, prevent progressive deformity, and obtain the maximum correction necessary to achieve spinal balance in the coronal and sagittal plane. The final scoliosis correction averaged 43%. Physiologic sagittal alignment was achieved in all patients. Complications occurred in seven patients (43%). It is our conclusion, based on this series, that the concept of decancellation, radical vertebral column resection, spinal shortening, and segmental instrumentation posteriorly can achieve a balanced correction and significant pain relief for the select patient who presents with severe rigid spine deformity not adequately treatable by more established techniques.     

脊柱去松质骨截骨治疗僵硬性脊柱侧凸的有效性及安全性分析

目的 探讨脊柱去松质骨截骨(VCD)治疗僵硬性脊柱侧凸畸形的有效性及安全性.方法 回顾性分析2004年5月至2008年2月实施VCD的32例僵硬性脊柱侧凸畸形患者的临床资料.其中男性12例,女性20例;平均年龄18岁(10～56岁).手术技术包括多节段VCD,切除顶椎区域残留椎间盘,对脊柱侧凸畸形进行矫形并后路椎弓根钉内固定.随访时除行常规X线片检查外,部分病例采用CT三维重建技术对截骨部位融合情况进行评估.通过术前术后X线片对矫形效果进行评价,并对术中、术后并发症情况进行统计分析.结果 本组平均切除2.1个椎体,平均固定融合10.6个节段(范围:8～13个节段).平均手术时间270 min(215～380 min).术中平均出血1560 ml(范围:900～4800 ml).4例患者出现手术并发症,其中出现一过性神经症状2例,脑脊液漏1例,硬膜外血肿1例.患者均获随访,随访时间24～48个月,平均31个月.术前冠状面Cobb角92°～138°,平均108°,术后矫正至32°～51°,平均42°;平均矫正率为61%.矢状面Cobb角术前平均82.0°,术后矫正至28.7°.所有患者截骨部位获得坚固融合,没有发现断钉断棒及内固定松动等并发症.结论 单纯后路VCD治疗僵硬性脊柱侧凸畸形安全有效.     

严重脊柱侧后凸畸形后路全脊椎截骨术后残留后凸畸形的原因及处理策略

目的 对严重脊柱侧后凸后路全脊椎截骨术后残留后凸畸形的危险因素进行分析,并提出相应的处理策略.方法 2002年4月至2006年1月,采用后路经椎弓全脊椎截骨术矫治严重脊柱侧后凸畸形患者75例,男39例,女36例;年龄10～32岁,平均16.9岁.术前侧凸Cobb角平均72°(51°～130°),后凸Cobb角平均82°(69°-147°).7例术前存在不同程度的下肢不全性瘫痪症状.治疗策略:一期后路经椎弓顶椎区全脊椎截骨、矫形内固定术.根据术后残留后凸的程度,75例中有28例又进行了二期前路凹侧自体胫骨条支撑融合术(A组,11例)或凸侧植骨融合术(B组,17例).结果 后路截骨术后28例残留后凸,其原因为:术前后凸过大(＞100°)11例,同侧连续半椎体5例,半椎体伴分节不良4例,凹侧截骨不充分3例,肋骨头切除不足2例,人为残留3例.全组无死亡,无感染.28例残留后凸患者中22例获得平均21个月的随访,A组1例术后12个月因支撑胫骨条骨折而发现假关节,固定棒断裂;1例存在假关节可能,其余病例均达到骨性融合.1例术后因外伤发生原胫骨取骨处骨折.B组病例均骨性融合,无一例发生脱钩或断棒等内固定并发症.结论 对严重脊柱侧后凸后路全脊椎截骨术后残留较大后凸畸形的患者,二期行前路凹侧支撑或凸侧植骨融合术,可减少术后远期发生内固定失败、畸形加重及神经损害等并发症.     

一期后路病灶清除、楔形截骨矫形治疗胸腰椎结核并后凸或侧后凸畸形

目的探讨一期后路病灶清除、楔形截骨矫形及内固定治疗胸、腰椎结核并后凸或侧后凸畸形的可行性、应用指征及临床意义。方法对16例胸、腰椎结核并后凸或侧后凸畸形的患者采取一期后路病灶清除、楔形截骨矫形及内固定术。男性12例,女性4例,年龄17~53岁,平均37 1岁。术前后凸角为54°~138°,平均78 3°; 2例合并侧凸,角度分别为31°和24°; 1例伴随侧方移位。7例合并脊髓损害, 2例为C级, 5例为D级, 2例表现为马尾及神经根损害。结果手术时间为215~325min,平均265min,术中出血450~2200ml,平均1100ml。术后结果满意, 14例为优, 2例为良,无严重并发症发生,脊髓神经功能损害均获显著改善。术后后凸角度为0°~67°,平均28 5°,矫正率63 6%,侧凸和侧方移位基本矫正。随访14 ~52个月,平均26 3个月。无内固定松动、断裂及明显矫正度丢失,融合良好。结论对胸、腰椎结核并后凸或侧后凸畸形的患者采取一期后路病灶清除、楔形截骨矫形及内固定术是一较为有效、可行的方法。与联合前、后路手术比较,该技术减少了创伤且有更好的畸形矫正效果。     

Changes in surface and radiographic deformity after Universal Spine System for right thoracic adolescent idiopathic scoliosis: is rib-hump reassertion a mechanical problem of the thoracic cage rather than an effect of relative anterior spinal overgrowth?

STUDY DESIGN: Analysis of preoperative, 8-week, 1-year, and 2-year data from patients with right thoracic adolescent idiopathic scoliosis treated by posterior Universal Spine System (Stratec Medical, Oberdorf, Switzerland). OBJECTIVE: Report 2-year results and the association between back surface and radiographic assessments. SUMMARY OF BACKGROUND DATA: Few longitudinal studies have related surface and radiographic data in the follow-up of surgical patients. METHODS: Of 34 patients with right thoracic adolescent idiopathic scoliosis having posterior Universal Spine System instrumentation, 27 had complete prospective back surface and radiographic appraisal. RESULTS: Cobb angle corrected from 58 degrees to 34 degrees (41%), apical vertebral rotation from 26 degrees to 20 degrees (23%), apical vertebral translation from 4.5 to 2.4 cm (47%), and maximum angle of trunk inclination from 17 degrees to 13 degrees (22%) (preoperative to 2 years). Rib-hump reassertion occurred between 8 weeks and 1 year, regardless of age, and correlated with changes in vertebral translation (for 10 vertebral levels corresponding to 10 back surface levels between C7 and S1, P = 0.001 MANOVA). Preoperative frontal tilt of L1 with concave fifth rib-spinal angle predicted the percentage correction of maximum angle of trunk inclination, and the concave ninth rib-spinal angle predicted reassertion of maximum angle of trunk inclination. CONCLUSIONS: Almost half of initial back surface correction is lost by 2 years. Segmental vertebral translation measurements most strongly correlate with segmental angle of trunk inclination measurements during follow-up. Rib-hump reassertion is best explained by unwinding of the thoracic cage tensioned by surgery rather than through relative anterior spinal overgrowth. Spine and thoracic cage factors determine rib-hump correction, so surgical disruption of the latter by costoplasty may prevent rib-hump reassertion. Results of scoliosis surgery should include surface data.     

Scanning stereographic surface measurement in idiopathic scoliosis after VDS (ventral derotation spondylodesis)

INTRODUCTION: So far only radiometric and clinical methods have been available for the evaluation of results after anterior scoliosis surgery. Rasterstereography has proved to be a reliable method for three-dimensional surface measurement of conservatively treated idiopathic scoliosis patients. Therefore, patients treated operatively with anterior instrumentation were examined using rasterstereography to determine the three-dimensional correction of the spinal deformity. The aim was to measure back shape deformity, in particular derotation, and thus cosmetic improvements. METHODS: 31 patients with idiopathic thoracic, thoracolumbar and lumbar scoliosis (Cobb angle 57.2 degrees) were examined with raster stereography preoperatively, postoperatively and after follow-up (25.2 months) in a standardized standing posture. Standing radiographs were compared with raster stereography. RESULTS: The mean Cobb angle was reduced from 57.2 degrees to 17.2 degrees, the rasterstereographic maximal surface rotation from 16.5 degrees to 10.8 degrees, and the vertebral rotation according to Perdriolle from 29.2 degrees to 16.7 degrees. During follow-up the Cobb angle increased to 20.8 degrees, and surface rotation to 11.3 degrees. Vertebral rotation remained constant. Lordosis and kyphosis angles changed only slightly. CONCLUSION: Rasterstereography is a suitable tool for analyzing the three-dimensional correction of spinal deformities after anterior scoliosis surgery. In particular, the cosmetic improvement is clearly demonstrated. The measurement of surface rotation allows objective quantification of the obtained derotation.     

Comparative evaluation of single-level closing-wedge vertebral osteotomies for the correction of fixed kyphotic deformity of the lumbar spine: a cadaveric study.

STUDY DESIGN: Anatomic study. OBJECTIVES: To compare spinal osteotomies with respect to obtainable correction and change in anterior height and distance of the spinal column and to describe a modification of the decancellation closing-wedge osteotomy to obtain further correction. SUMMARY OF BACKGROUND DATA: Fixed kyphotic deformity of the lumbar spine can cause difficulty with sitting, lying flat, and pain and can pose a risk to adjacent spinal cord and nerves as well as impair respiratory and abdominal function. Various corrective osteotomies have been described. Osteotomies involving decancellation and a closing wedge of the apical vertebra theoretically decrease the risk to anterior vascular structures. METHODS: Single-level vertebral osteotomies were performed on three groups of fresh-frozen human cadaveric lumbar spines. Group 1 underwent a conventional anterior opening-wedge/posterior closing-wedge osteotomy, Group 2 underwent a conventional decancellation posterior closing-wedge osteotomy, and Group 3 underwent our modified decancellation posterior closing-wedge osteotomy. Sagittal plane angulation as well as anterior height and distance of the spinal column were measured before and after osteotomy. RESULTS: The mean correction was 38 degrees for Group 1, 36 degrees for Group 2, and 49 degrees for Group 3. The mean change in anterior height and distance was 20 and 30 mm, respectively, for Group 1. For Groups 2 and 3 it was only 2-4 mm. CONCLUSIONS: The authors recommend single-level posterior decancellation procedures for correction of fixed kyphotic deformities of the thoracolumbar spine to decrease the risk to anterior neurovascular structures. An additional 10-13 degrees of correction can be obtained with the authors' modification.