先天性脊柱侧凸美学指标与影像学指标的相关性研究

目的探讨分节障碍型先天性脊柱侧凸(congenital scoliosis, CS)患者的美学指标与影像学指标的相关性, 以及美学指标的临床意义。方法回顾性分析27例分节障碍型CS患者的临床及影像学资料, 所有患者均摄正、侧位全脊柱X线片, 以及自然站立位背部及前屈位的大体照片。大体照片测量以下7个美学指标:肩部面积指数1(shoulder area index 1, SAI1)、肩部面积指数2(shoulder area index 2, SAI2)、腰部面积指数(lumbar area index, LAI)、肩角(shoulder angle, α1)、腋窝角(axilla angle, α2)、左右腰角差(right and left waist angle difference, RLWAD)和剃刀背指数(hump index);同时在患者术前X线片上测量7个影像学指标:影像肩高差(radiographic shoulder height difference, RSHD)、T1倾斜(T1 tilt)、第一肋角(first rib angle, FRA)、锁骨角(clavic...     

青少年特发性脊柱侧弯患者肩部影像学与肩部外观的相关性研究

[目的]对新定义的肩部影像学参数进行分析,进一步研究青少年特发性脊柱侧弯患者(adolescent idiopathic scoliosis,AIS)肩部影像学与肩部外观的相关性.[方法]选取本院接受治疗的连续35例含主胸弯青少年特发性脊柱侧弯患者,Lenke 1型21例,Lenke 2型14例,主胸弯Cobb角平均(48±7.3)°,上胸弯Cobb角平均(21±4.5)°.均拍摄自然站立位脊柱X线片及肩背部外观照,量取肩部影像学参数T1倾斜角、锁骨角、锁骨胸廓交点差、喙突高、锁骨差1、锁骨差2,及两个肩部外观参数临床肩高1、临床肩高2.对肩部影像学参数与外观参数分别进行相关分析,探讨锁骨差1、锁骨差2与肩部外观的相关性.[结果]除T1倾斜角外,所研究的影像学参数与外观参数显示明显的相关性(P＜0.05);但仅有锁骨差1与临床肩高2、锁骨差2与两个外观参数有较高的相关关系(r＞0.80),其中锁骨差2与临床肩高2显示最强的相关关系(P＜0.01,r=0.97);临床肩高2较临床肩高l与肩部影像学参数显示更强的相关性.[结论]肩部影像学参数锁骨差2可以更好反映临床外观肩高,参考影像学资料可以较准确地评价患者的部分肩部外观特征.     

Lenke 1型青少年特发性脊柱侧凸患者不同上端融合椎对术后双肩平衡的影响

【摘要】 目的：探讨不同上端融合椎对术前双肩水平的Lenke 1型青少年特发性脊柱侧凸（adolescent idiopath?鄄ic scoliosis,AIS）患者术后双肩平衡的影响。方法：选取2006年6月~2009年6月在我院行后路主胸弯融合术并有2年以上完整影像学随访资料的32例Lenke 1型AIS患者。所有患者术前均表现为双肩水平,其中男6例,女26例,手术时年龄13~19岁,平均14.9岁,上胸弯Cobb角平均为23.7°±8.0°（10°~36°）,主胸弯Cobb角平均47.5°±6.9°（40°~62°）。按照上端融合椎不同将AIS患者分为两组：A组,上端融合椎为T3,19例;B组,上端融合椎为T4,13例。A组患者的手术时年龄、Risser征、上胸弯及主胸弯柔韧度与B组比较均无统计学差异（P>0.05）。采用方差分析比较两组患者术前、术后1年和末次随访时的上胸弯及主胸弯Cobb角、顶椎及躯干偏移距离、影像学肩关节高度差（radiographic shoulder height, RSH）、喙突高度差（CPH）和锁骨角（CA）。结果：A组随访时间2~4.5年,平均3.6±1.3年;B组随访时间2~4.8年,平均3.1±2.1年,两组比较无统计学差异（P>0.05）。术前、术后1年和末次随访时,A组患者的上胸弯Cobb角、主胸弯Cobb角、顶椎及躯干偏移距离、RSH、CPH及CA与B组比较均无统计学差异（P>0.05）。A、B两组患者术后1年和末次随访时的上胸弯Cobb角、主胸弯Cobb角、顶椎及躯干偏移距离、RSH、CPH、CA分别与术前比较均有显著性改善（P<0.05）;末次随访时,两组患者的上胸弯Cobb角及RSH、CPH、CA较术后1年均显著减小（P<0.05）,均获得较满意的双肩平衡。结论：对于术前双肩水平的Lenke 1型AIS患者,上端融合椎为T3或T4对重建术后双肩平衡的疗效无明显差别;对此类患者上端融合至T4即可获得良好的矫形效果和满意的双肩平衡。     

Lenke I型脊柱侧弯肩部平衡的2年随访研究

[目的]评估单胸弯(LenkeⅠ型)特发性脊柱侧凸矫正患者术后及最少2年随访过程中肩部平衡的变化过程。[方法]回顾性分析2008年7月~2012年8月在本院脊柱侧弯中心接受手术治疗的特发性脊柱侧凸患者72例,男14例,女58例;平均年龄15.8岁(9~21岁),平均随访29.7个月(24~62个月)。均为LenkeⅠ型。研究利用术前术后及随访的全脊柱正侧位X线片测量双肩高度差、锁骨角等指标,并利用统计学软件SPSS 17对参数进行比较,分析手术及术后不同随访时间对患者肩部平衡的影响。[结果]72例患者皆采用单纯后路椎弓根钉棒矫正,手术完成顺利,无严重并发症发生。其中主胸弯Cobb角从术前平均(53.7±11.1)°矫正至术后平均(11.1±7.4)°,平均主弯矫正率为77.7%;上胸弯Cobb角从术前平均(23.2±7.6)°矫正至术后平均(7.4±11.1)°,平均主弯矫正率为70.6%。术前双肩高度差(RSH)及锁骨角(CA)分别为平均(1.3±1.0)cm和(3.0±1.9)°,术后矫正至平均(1.7±1.1)cm和(3.9±1.8)°,半年随访平均(1.4±1.0)cm和(3.0±1.8)°,1年随访平均(1.2±1.2)cm和(2.8±1.8)°,2年后随访平均(1.1±1.0)cm和(2.7±1.6)°,双肩高度差在术后及末次随访差异皆具统计学意义(P0.05);在术后两年的随访中,RSH和CA指数分别得到了35%及31%的恢复,其术后1年内恢复所占比例分别为95%及97%。[结论]对于Lenke I型患者来说,手术矫正可能会导致肩部不平衡情况加重,但术后所残留的肩部不等高在术后远期功能重建中可以得到较好的恢复,而术后1年的时间段是肩部平衡恢复重建的关键时期。     

Lenke 1型青少年特发性脊柱侧凸病人矫形术后肩平衡的相关因素分析

目的 探讨术前右肩高Lenke 1型青少年特发性脊柱侧凸（adolescent idiopathic scoliosis,AIS）病人术后的肩关节高度变化,并分析术后肩平衡的影响因素。方法 回顾性分析2015年1月至2017年12月于我院手术治疗的术前右肩高Lenke 1型AIS病人41例,根据术后肩部平衡状态分为双肩平衡组和双肩失衡组。分别测量两组病人术前、术后3个月及术后2年的影像学肩关节高度差（radiographic shoulder height,RSH）、上胸弯Cobb角、主胸弯Cobb角、锁骨角、胸廓锁骨角度差（clavicle chest cage angle difference,CCAD）和T₁倾斜角,并计算主胸弯矫正率、上胸弯矫正率、主胸弯柔韧度、上胸弯柔韧度等;分析双肩失衡组病人末次随访时RSH与术前影像学指标的相关性。结果 双肩失衡组术前的锁骨角和CCAD值均高于双肩平衡组,上胸弯柔韧度低于双肩平衡组（P＜0.05）。Pearson相关分析显示术前锁骨角、CCAD与术后RSH呈正相关（P＜0.05,r＞0）;上胸弯柔韧度与术后RSH呈负相关（P＜0.05,r＜0）;锁骨角变化、主胸弯及上胸弯矫正率、主胸弯角度变化与RSH变化呈正相关（P＜0.05,r＞0）。Logistic回归分析未见双肩失平衡的独立危险因素。结论 术前锁骨角、CCAD及上胸弯柔韧度是Lenke 1型AIS病人术后RSH的预测因素,应避免主胸弯过度矫正导致术后肩失衡的发生。     

不同脊柱侧凸类型与胸锁关节病变的相关性研究

目的 探讨不同脊柱侧凸类型与胸锁关节病变的相关性.方法 回顾性分析自2018-01-2020-01诊治的85例脊柱侧凸,比较各脊柱侧凸类型T1倾斜角、双肩高度差、锁骨角,采用Pearson相关性检验对T1倾斜角、双肩高度差、锁骨角与胸锁关节病变的相关性进行分析.结果 85例均获取完整的影像学资料.Lenke Ⅰ型17例...     

胸弯为主的青少年特发性脊柱侧凸后路矫形术后肩部失平衡的危险因素分析

【摘要】 目的：观察以胸弯为主的青少年特发性脊柱侧凸（AIS）患者后路矫形术后肩部失平衡的发生情况,探讨其危险因素。方法：回顾性分析96例以胸弯为主的AIS患者的临床资料,Lenke分型为Lenke 1、2、3、4型,均为右胸弯且Cobb角＜80°。男15例,女81例;年龄10～18岁,平均14.5岁。均采用后路椎弓根螺钉系统固定矫形,随访22～68个月,平均42.2个月。根据术后肩部平衡情况,将患者分为肩部平衡组和肩部失平衡组,分析比较两组患者的临床资料和影像学特点。结果：肩部失平衡患者17例,发生率为17.7%。单变量分析和Logistic回归分析的结果发现与术后肩部失平衡相关的3个独立因素为：术前锁骨角（OR=1.873,P=0.018）、术前主胸弯Cobb角（OR=2.222,P=0.028）和术后主胸弯Cobb角（OR=0.483,P=0.039）。其中锁骨角和术前主胸弯Cobb角为危险因素,术前锁骨角的正值越大,主胸弯角度越大,术后肩部失平衡的危险性越大;术后主胸弯Cobb角为保护因素,术后主胸弯残余角度较大时,能相对避免肩部失平衡的发生。结论：术前锁骨角为正性倾斜、主胸弯角度较大和术后主胸弯残余角度过小可能是AIS患者主胸弯矫正后肩部失平衡的独立危险因素。     

特发性脊柱侧凸患者肩部失平衡的临床分析及其意义

目的：对不同类型特发性脊柱侧凸（idiopathic scoliosis,IS）患者肩部失平衡情况进行观察,探讨避免肩部失平衡的融合节段选择方案.方法：对137例随访2年以上资料完整的IS患者进行回顾性分析.对术前及术后的肩部平衡进行影像学评价.根据可能影响肩部平衡的因素（上胸椎侧凸情况、各个侧凸间相互平衡情况及主侧凸角度大小）将患者的Lenke分型进一步分为不同类型.分析各因素及手术融合方式对肩部平衡产生的影响.结果：术前肩部失平衡的病例71例;其中显著肩部失平衡22例;重度肩部失平衡10例,均为Lenke 1型及Lenke 2型.这些患者均存在较大角度的上胸椎侧凸（非结构性或结构性）.术后6例显著肩部失平衡.其中Lenke 1型第一类型1例,Lenke 2型第一类型1例,Lenke 2型第三类型4例,手术方式均为选择性融合.对Lenke 2型第二类型进行双侧凸融合,术后肩部失平衡改善.结论：术前肩部不平衡主要为Lenke 1型及Lenke 2型患者.上胸椎侧凸畸形对肩部平衡产生关键性影响.对Lenke 2型第二及第三类型不建议行选择性融合,对Lenke 2型第一类型进行选择性融合时应避免过度矫正.     

Lenke 1型特发性脊柱侧凸选择性胸弯融合时的下端融合椎选择:T12还是L1?

[目的]比较不同下端固定椎的Lenke1型青少年特发性脊柱侧凸患者(adolescent idiopathic scoliosis,AIS)选择性融合术后影像学改变.[方法]选取行选择性胸椎融合术的52例Lenke1型AIS患者.按照融合下端椎将52例AIS患者分为两组:A组(下端融合椎为T12)及B组(下端融合椎为L1),进一步根据Lenke分型将Lenke 1A(下端融合椎为T12/L1)及Lenke 1B/1C(下端融合椎为T12/L1)患者分别行矫形效果分析.[结果]术前A、B两组间各相关参数均未见统计学差异.A组患儿术后末次随访时胸腰弯/腰弯顶椎偏移、冠状面平衡、下端融合椎下位椎间盘冠状面成角及远端交界性后凸均显著大于B组患儿(P＜0.05).根据腰弯修正型分为两组:Lenke 1A及Lenke 1B/C组.无论是下端融合椎为T12或L1的Lenke 1A型患者术后均取得较为满意的矫形效果,冠状面及矢状面影像学改变无显著统计学差异;而Lenke 1B/C(下端融合椎为L1)患者在冠状面及矢状面的矫形效果较好.[结论]在对Lenke 1型患者行选择性融合术时应结合腰弯修正型制定手术策略:对于腰弯柔韧性佳的Lenke 1A患者只需融合至T12即可,而Lenke 1B/C患者的融合范围应延伸至L1.     

Lenke 1型青少年特发性脊柱侧凸患者术后双肩失平衡的影像学评估

[目的]对行全椎弓根螺钉治疗的Lenke 1型青少年特发性脊柱侧凸患者术后双肩失平衡的影像学危险因素进行分析。[方法]选择长海医院行全椎弓根螺钉治疗的Lenke 1型青少年特发性脊柱侧凸患者80例,随访至少2年。测量T1倾斜(T1 tilt)、锁骨角(clavicle angle,CA)、影像学肩高(radiographic shoulder height,RSH)等影像学参数。根据RSH分级的绝对值术后是否大于术前,将其分为术后平衡组与失平衡组,并对两组患者的影像学参数进行对比分析。[结果]术后双肩失平衡的发生率为22.5%。双肩失平衡组正性T1倾斜、正性锁骨角的比例远高于平衡组(P<0.001)。术前双肩水平的患者术后更易出现双肩失平衡(25.8%vs 83.3%,P<0.001)。25.8%的双肩平衡患者上胸弯Cobb角≥30°,而双肩失平衡患者该比例高达55.6%(P=0.018);50.0%的双肩平衡患者主胸弯与上胸弯的Cobb角差值≥25°,而双肩失平衡患者该比例仅为22.2%(P=0.036)。平衡组30.6%患者随访时主胸弯与上胸弯矫正率的差值≥1.8,失平衡组中该比例达61.1%(P=0.019)。[结论]T1倾斜、锁骨角、术前双肩平衡状态、上胸弯Cobb角、主胸弯与上胸弯的Cobb角差值及主胸弯与上胸弯矫正率的比值是较好的预测Lenke 1型青少年特发性脊柱侧凸患者术后双肩失平衡的影像学参数。     

Discrepancy between radiographic shoulder balance and cosmetic shoulder balance in adolescent idiopathic scoliosis patients with double thoracic curve

Shoulder balance is one of the key components to the body deformity in adolescent idiopathic scoliosis (AIS) patients with double thoracic curve and shoulder cosmesis plays an important role in patients’ satisfaction of surgical outcomes. Up to now, only radiographic parameters were used to evaluate the shoulder balance in literatures; no corresponding cosmetic parameters have been developed to evaluate the cosmetic shoulder balance. Meanwhile, we often confronted that perfect radiographic shoulder balance was achieved, but the patients complained about the residual cosmetic deformity. This phenomenon implied that discrepancy may exist between radiographic shoulder balance and cosmetic shoulder balance. The present study was carried out to investigate the correlation between radiographic and clinical cosmetic shoulder balance in AIS patients with double thoracic curve. Thirty-four AIS patients were recruited for this study. All the patients had a double thoracic curve. Six cosmetic parameters––inner shoulder height (SHi), outer shoulder height (SHo), shoulder area index 1 (SAI1), shoulder area index 2 (SAI2), shoulder angle (α1) and axilla angle (α2) were developed and measured on the standing photographs. Also, seven radiographic parameters––T1 tilting (T1), first rib angle (FRA), clavicle angle (CA), coracoid process height (CPH), clavicle-rib cage intersection (CRCI), first rib–clavicle height (FRCH), trapezius length (TL) were measured on the standing posterior–anterior radiographs. Correlation analysis was made between cosmetic parameters and radiographic parameters. SHi was found to be significantly correlated with T1, FRA, CA, CPH, CRCI (P < 0.05), among which FRA had the highest correlation coefficient. SHo was found to be significantly correlated with T1, FRA, CA, CPH, CRCI, FRCH (P < 0.05), among which CRCI had the highest correlation coefficient. However, none of the correlation coefficient was greater than 0.8. The correlation coefficients between radiographic parameters and SAI1, SAI2, α1, α2 were also below 0.8 that were similar with SH. The results indicated that radiographic parameters could only partially reflect the shoulder cosmetic appearances. However, none of the existing parameters can accurately reflect the shoulder cosmetic appearance. As cosmesis is critical important to patients’ satisfaction, spine surgeons should pay more attention to the cosmetic shoulder balance rather than radiographic shoulder balance.     

Is neck tilt and shoulder imbalance the same phenomenon? A prospective analysis of 89 adolescent idiopathic scoliosis patients (Lenke type 1 and 2)

Purpose

To introduce a new clinical neck tilt grading and to investigate clinically and radiologically whether neck tilt and shoulder imbalance is the same phenomenon in AIS patients.

Methods

89 AIS Lenke 1 and 2 cases were assessed prospectively using the new clinical neck tilt grading. Shoulder imbalance and neck tilt were correlated with coracoid height difference (CHD), clavicle\rib intersection distance (CRID), clavicle angle (CA), radiographic shoulder height (RSH), T1 tilt and cervical axis.

Results

Mean age was 17.2 ± 3.8 years old. 66.3 % were Lenke type 1 and 33.7 % were type 2 curves. Strong intraobserver (0.79) and interobserver (0.75) agreement of the clinical neck tilt grading was noted. No significant correlation was observed between clinical neck tilt and shoulder imbalance (0.936). 56.3 % of grade 3 neck tilt, 50.0 % grade 2 neck tilt patients had grade 0 shoulder imbalance. In patients with grade 2 shoulder imbalance, 42.9 % had grade 0, 35.7 % grade 1, 14.3 % grade 2 and only 7.1 % had grade 3 neck tilt. CHD, CRID, CA and RSH correlated with shoulder imbalance. T1 tilt and cervical axis measurements correlated with neck tilt.

Conclusions

In conclusion, neck tilt is distinct from shoulder imbalance. Clinical neck tilt has poor correlation with clinical shoulder imbalance. Clinical neck tilt grading correlated with cervical axis and T1 tilt whereas clinical shoulder grading correlated with CHD, RSH CRID and CA.

     

Right adolescent idiopathic thoracic curve (Lenke 1 A and B): does cost of instrumentation and implant density improve radiographic and cosmetic parameters?

In adolescent idiopathic scoliosis (AIS) there has been a shift towards increasing the number of implants and pedicle screws, which has not been proven to improve cosmetic correction. To evaluate if increasing cost of instrumentation correlates with cosmetic correction using clinical photographs. 58 Lenke 1A and B cases from a multicenter AIS database with at least 3 months follow-up of clinical photographs were used for analysis. Cosmetic parameters on PA and forward bending photographs included angular measurements of trunk shift, shoulder balance, rib hump, and ratio measurements of waist line asymmetry. Pre-op and follow-up X-rays were measured for coronal and sagittal deformity parameters. Cost density was calculated by dividing the total cost of instrumentation by the number of vertebrae being fused. Linear regression and spearman’s correlation were used to correlate cost density to X-ray and photo outcomes. Three independent observers verified radiographic and cosmetic parameters for inter/interobserver variability analysis. Average pre-op Cobb angle and instrumented correction were 54° (SD 12.5) and 59% (SD 25) respectively. The average number of vertebrae fused was 10 (SD 1.9). The total cost of spinal instrumentation ranged from $6,769 to $21,274 (Mean $12,662, SD $3,858). There was a weak positive and statistically significant correlation between Cobb angle correction and cost density (r = 0.33, p = 0.01), and no correlation between Cobb angle correction of the uninstrumented lumbar spine and cost density (r = 0.15, p = 0.26). There was no significant correlation between all sagittal X-ray measurements or any of the photo parameters and cost density. There was good to excellent inter/intraobserver variability of all photographic parameters based on the intraclass correlation coefficient (ICC 0.74–0.98). Our method used to measure cosmesis had good to excellent inter/intraobserver variability, and may be an effective tool to objectively assess cosmesis from photographs. Since increasing cost density only improves mildly the Cobb angle correction of the main thoracic curve and not the correction of the uninstrumented spine or any of the cosmetic parameters, one should consider the cost of increasing implant density in Lenke 1A and B curves. In the area of rationalization of health care expenses, this study demonstrates that increasing the number of implants does not improve any relevant cosmetic or radiographic outcomes.     

Does anterior shoulder balance in adolescent idiopathic scoliosis correlate with posterior shoulder balance clinically and radiographically?

Purpose

Patients with adolescent idiopathic scoliosis (AIS) often present with a disfiguring shoulder imbalance. Shoulder balance (Sh.B) is of significant importance to the patient’s self-perception. Previous studies have correlated Sh.B with respect to only the clinical posterior view correlated with radiographs. It is important, however, to address Sh.B with respect to anterior view of the patients’ shoulders as if patients were viewing in a mirror. In this study, we evaluated the anterior Sh.B and correlated it with posterior Sh.B clinically and radiographically in Lenke type 1 and 2 curves.

Method

An online scoliosis database was queried to identify 74 AIS patients with Lenke 1 (n = 55, age 15.28 ± 3.35) and 2 (n = 19, age 15.66 ± 3.72) curves with a complete set of PA radiographs and anterior and posterior photos. Radiographic measures for Sh.B included Cobb angles, T1 tilt, first rib angle, and clavicle-rib intersection angle. Clinical measures for Sh.B included inner shoulder angle, outer shoulder angle, and axillary fold angle. Regression analysis with Pearson’s correlation and ANOVA for statistical significance was used for analysis.

Results

For Lenke 1 curves, there was moderate statistically significant correlation between anterior and posterior clinical Sh.B (R = 0.35–0.41). There was only weak to moderate correlation between radiographic and clinical measures. For Lenke 2 curves, there was a weak to moderate correlation between anterior and posterior clinical Sh.B (R = 0.25–0.45), though not statistically significant. There was no statistically significant correlation between any radiographic measures and posterior Sh.B. There was, however, moderate and significant correlation between radiographic measures and anterior Sh.B.

Conclusion

There is no strong correlation between anterior and posterior clinical Sh.B, and surgeons should evaluate both sides in planning deformity correction, especially in Lenke 2 curves. None of the radiographic measures showed strong correlation (R > 0.8) with anterior or posterior clinical Sh.B. A stronger correlation existed between radiographic measures and anterior Sh.B measurements compared with posterior clinical Sh.B measurements in Lenke 2 curves further necessitating anterior evaluation in this group.     

Subjective evaluation of treatment outcomes of instrumentation with pedicle screws or hybrid constructs in Lenke Type 1 and 2 adolescent idiopathic scoliosis: what happens when judges are blinded to the instrumentation?

Superiority of pedicle screws over hybrid/hook instrumentation or vice versa in the treatment of Lenke Type 1 and 2 adolescent idiopathic scoliosis (AIS) remains unresolved for moderate curves. Our objective was therefore to compare the assessment of pedicle screw and hybrid/hooks instrumentation with special attention to cosmesis and uninstrumented spine using novel assessment methods. We carried out a retrospective study of radiographs and clinical photos of 40 cases of thoracic AIS between 40° and 70° of Cobb angle Lenke Type 1 and 2, treated with either pedicle screws or hybrid/hooks. The cases were subjectively assessed by four spine surgeons (SRS Travelling Fellows) for radiographic and operative cosmetic result, shoulder balance, trunk shift, rib hump, and waist asymmetry. Instrumentation in the radiographs was obscured with only the non-instrumented part visible, and the surgeons were asked to guess the instrumentation being used. Eighty photographs of patients before and after surgery were assessed for cosmesis by ten non-medical judges for overall cosmetic score, shoulder balance, waist asymmetry, and shoulder blade prominence. Objective assessment of radiographs and clinical photos was performed for Cobb angle of instrumented and non-instrumented spine, global coronal and sagittal balance, number of unfused vertebrae, disc angulation, tilt of last instrumented vertebra, shoulder balance, waist asymmetry, rib prominence, and percent correction. SRS-24 questionnaire was used to measure health-related quality of life in patients. Subjective assessments by surgeons and non-medical judges showed no significant difference by instrumentation (P ≥ 0.05) for all variables. Out of the 160 guesses by surgeons of the cases with instrumentation blocked in the radiographs, they were unable to guess the instrumentation in 92% of the cases. Objective assessment of all variables and SRS-24 scores of all five domains showed no significant difference by instrumentation (P ≥ 0.05). In this first-ever conducted study in a blinded-fashion, we conclude that there is no significant difference between the pedicle screw and hybrid/hooks instrumentations used to treat AIS for Lenke Type 1 and 2 curves for moderate curves between 40° and 70°.     

The mechanisms underlying the variety of preoperative directionalities of shoulder tilting in adolescent idiopathic scoliosis patients with double thoracic curve

Purpose

Preoperative directionality of shoulder tilting seems to be independent of the radiographic features of proximal thoracic (PT) curve in adolescent idiopathic scoliosis (AIS) patients. To date, no study had investigated the mechanisms underlying the variety of preoperative directionalities of shoulder tilting in AIS patients. The purpose of this study was to evaluate the differences of radiographic features between Lenke type 2 (double thoracic curve) AIS patients with different preoperative directionalities of shoulder tilting.

Methods

A total of 130 Lenke type 2 AIS patients were included in this study and were divided into two groups according to the value of radiographic shoulder height (RSH). There were 78 cases (71 females and 7 males) with RSH less than 0 cm in Group A and 52 cases (44 females and 8 males) with RSH equal to or more than 0 cm in Group B. Preoperative standing anteroposterior X-ray films of the spine were obtained in all these subjects and were analyzed with respect to the following parameters: T1 tilt, PT Cobb angle, main thoracic (MT) Cobb angle, the apical level of PT curve, the apical level of MT curve, and RSH. These parameters were compared between these two groups and the correlations between RSH and the other parameters were analyzed in all of these subjects.

Results

No significant difference was found between these two groups with respect to PT Cobb angle or the apical level of PT curve (P > 0.05). The apical level of MT curve was significantly more proximal in Group A compared with Group B (P < 0.05). The MT Cobb angle was significantly larger in Group A compared with Group B (P < 0.05). Both the T1 tilt and the PT Cobb angle/MT Cobb angle ratio in Group A were significantly smaller than those in Group B (P < 0.05). The RSH was positively associated with T1 tilt, the apical level of MT curve, and the PT Cobb angle/MT Cobb angle ratio, but was negatively associated with MT Cobb angle (P < 0.05).

Conclusion

The directionality of shoulder tilting is diverse in Lenke type 2 AIS patients. The preoperative directionality of shoulder mainly depends on the profile of MT curve rather than that of PT curve. The RSH should be carefully evaluated before making a surgical plan in these patients.

     

Do Current Recommendations for Upper Instrumented Vertebra Predict Shoulder Imbalance? An Attempted Validation of Level Selection for Adolescent Idiopathic Scoliosis

Background

Shoulder balance for adolescent idiopathic scoliosis (AIS) patients is associated with patient satisfaction and self-image. However, few validated systems exist for selecting the upper instrumented vertebra (UIV) post-surgical shoulder balance.

Questions/Purposes

The purpose is to examine the existing UIV selection criteria and correlate with post-surgical shoulder balance in AIS patients.

Methods

Patients who underwent spinal fusion at age 10–18 years for AIS over a 6-year period were reviewed. All patients with a minimum of 1-year radiographic follow-up were included. Imbalance was determined to be radiographic shoulder height |RSH| ≥ 15 mm at latest follow-up. Three UIV selection methods were considered: Lenke, Ilharreborde, and Trobisch. A recommended UIV was determined using each method from pre-surgical radiographs. The recommended UIV for each method was compared to the actual UIV instrumented for all three methods; concordance between these levels was defined as “Correct” UIV selection, and discordance was defined as “Incorrect” selection.

Results

One hundred seventy-one patients were included with 2.3 ± 1.1 year follow-up. For all methods, “Correct” UIV selection resulted in more shoulder imbalance than “Incorrect” UIV selection. Overall shoulder imbalance incidence was improved from 31.0% (53/171) to 15.2% (26/171). New shoulder imbalance incidence for patients with previously level shoulders was 8.8%.

Conclusions

We could not identify a set of UIV selection criteria that accurately predicted post-surgical shoulder balance. Further validated measures are needed in this area. The complexity of proximal thoracic curve correction is underscored in a case example, where shoulder imbalance occurred despite “Correct” UIV selection by all methods.

Electronic supplementary material

The online version of this article (doi:10.1007/s11420-015-9451-y) contains supplementary material, which is available to authorized users.     

Postoperative spinal alignment remodeling in Lenke 1C scoliosis treated with selective thoracic fusion

Background contextSelective thoracic fusion may cause spinal imbalance in certain patients; how the spinal alignment changes over time after surgery is highly correlated with the final spinal balance.PurposeTo investigate how spinal alignment changes over time after selective thoracic fusion and how spinal alignment remodeling affects spinal balance.MethodsAll adolescent idiopathic scoliosis (AIS) cases surgically treated in our institution between 2002 and 2008 were reviewed. Inclusion criteria were as follows: Lenke 1C scoliosis patients treated with posterior pedicle screw–only constructs; the lowest instrumented vertebra (LIV) ended at L1 level or above; and 2-year radiographic follow-up. Standing anteroposterior and lateral digital radiographs from four different time points (preoperatively, immediately, 3 months, and 2 years postoperatively) were reviewed. In each standing anteroposterior radiograph, the center sacral vertical line (CSVL, the vertical line that bisects the proximal sacrum) was first drawn, and the translation (deviation from the CSVL) of some key vertebrae was measured, such as the LIV, LIV+1 (the first vertebra below LIV), LIV+2 (the second vertebra below LIV), LIV+3 (the third vertebra below LIV), lumbar apical vertebra (AV), thoracic AV, and T1. Additionally, the Cobb angles of the major thoracic and lumbar curves were measured at different time points, and the correction rates were calculated. Furthermore, clinical photographs of the patients from the back were taken preoperatively and postoperatively.ResultsOf 278 AIS patients reviewed, 29 met the inclusion criteria. The continuous follow-up of our present study revealed an interesting phenomenon: postoperative spinal alignment remodeling. A hypothetical criterion was established to determine the onset of the phenomenon. By means of a series of analyses, the criterion was validated. The results of our present study showed that selective thoracic fusion tended to cause leftward spinal imbalance in these Lenke 1C AIS patients. Twenty of the 29 patients had leftward spinal imbalance immediately after surgery. Although some patients regained spinal balance through postoperative spinal alignment remodeling, 11 patients remained imbalanced at 2-year follow-up.ConclusionsSelective thoracic fusion is prone to cause leftward spinal imbalance in Lenke 1C scoliosis patients. Postoperative spinal alignment remodeling can facilitate recovery of spinal balance in some patients. Postoperative spinal imbalance in Lenke 1C scoliosis patients could be prevented by selecting stable vertebra or the vertebrae above as LIV, checking the balance condition during surgery, or considering ratio criteria when selecting candidates for selective thoracic fusion.     

Spinal coronal profiles and proximal femur bone mineral density in adolescent idiopathic scoliosis

Purpose

Although the occurrence and progression of AIS has been linked to low bone mineral density (BMD), the relationships between spinal curvature and bilateral differences in proximal femur BMD are controversial. Few correlation studies have stratified patients by curve type. The purpose of this study was to evaluate the relationships between spinal coronal profile and bilateral differences in proximal femur BMD in patients with adolescent idiopathic scoliosis (AIS).

Methods

This study included 67 patients with AIS who underwent posterior correction and fusion surgery between January 2009 and October 2011. The mean age at the time of surgery was 17.4 ± 4.1 years. Bilateral proximal femur BMD was measured before surgery by dual-energy X-ray absorptiometry. We compared the proximal femur BMDs by determining the bilateral BMD ratio (left proximal femur BMD divided by that of the right). We evaluated correlations between coronal parameters, obtained from preoperative radiographs, and the BMD ratio using Pearson’s correlation analysis.

Results

Patients with Lenke type 1 curve (48; all with a right convex curve) had a mean bilateral proximal femur BMD ratio of 1.00 ± 0.04. Patients with Lenke type 5 curve (19; all with a left convex curve) had a mean bilateral proximal femur BMD ratio of 0.94 ± 0.04, indicating that the BMD in the proximal femur on the right side (concave) was greater than that in the left (convex). Coronal balance was significantly correlated with the BMD ratio in both the Lenke type 1 and type 5 groups, with a correlation coefficient of 0.46 and 0.50, respectively.

Conclusions

The bilateral proximal femur BMD ratio was significantly correlated with the coronal balance in AIS patients. When the C7 plumb line was shifted toward one side, the BMD was greater in the contralateral proximal femur.