Abstract：
Background: The most common conservative treatment for Adolescent Idiopathic Scoliosis (AIS) is bracing. However, several papers questioned the effectiveness of bracing for curves between 40° and 50° Cobb: the effectiveness in preventing curve progression could be as low as 35%. Seriate casting is considered a standard approach in early onset scoliosis; however, in the setting of AIS, cast treatment is seldom utilized, with only few studies reporting on its effectiveness. Aim of the study: The main aim of the study is to determine whether a seriate casting with Risser casts associated with bracing is more effective in preventing curve progression than bracing alone in curves larger than 40°. Furthermore, the secondary endpoints were: (1) is there a difference in effectiveness of casting between Thoracic (T) and Thoracolumbar/Lumbar (TL/L) curves? (2) Does the ‘in cast’ correction predicts the treatment outcome? (3) What is the effect on thoracic kyphosis of casting? Methods: This is a retrospective monocentric case−control study; through an Institutional Database search we identified all the patients treated at our institution between 1 January 2017 and 31 December 2020, with a diagnosis of AIS, Risser grade between 0 and 4 at the beginning of the treatment, at least one curve above 40° Cobb and treatment with either seriate Risser casting and bracing (Study Group, SG) or bracing alone (Control Group, CG). Standing full spine X-rays in AP and LL are obtained before and after the cast treatment; only AP standing full spine X-rays ‘in-cast’ are obtained for each cast made. Patients were stratified according to the curve behavior at the end of treatment (Risser 5): progression was defined as ≥6° increase in the curve magnitude or fusion needed; stabilization is defined as a change in curve by ±5°; and improvement was defined as ≥6° reduction in the curve. Results: For the final analysis, 55 compliant patients (12 M, 43 F, mean age 13.5 ± 1.6) were included in the SG and 27 (4 M, 23 F, mean age 13.6 ± 1.6) in the CG. Eight (14.5%) patients in the SG failed the conservative treatment while 14 (51.3%) failed in the CG. Consequently, the Relative Risk for progression in the Efficacy Analysis was 1.8 (95% CI 1, 3−2.6, p = 0.001), and the Number Needed to Treat was 2,4. No significant difference was found between the T and TL/L curves concerning the ‘progressive’ endpoint (z-score 0.263, p = 0.79). The mean percentage of ‘in cast’ curve reduction was 40.1 ± 15.2%; no significant correlation was found between the percentage of correction and the outcome (Spearman Correlation Coefficient 0.18). Finally, no significant differences between baseline and end of FU TK were found (32° ± 16.2 vs. 29.6 ± 15.8, p = ns). Discussion: Seriate Risser casting for AIS with larger curves (>40° Cobb) is effective in reducing curve progression when compared with full time bracing alone in treatment compliant patients. The treatment is equally effective in controlling T and TL/L curves; furthermore, a slight but non-significant decrease in TK was observed in patients treated with casting. This type of treatment should be considered for AIS patients who present with large curves to potentially reduce the percentage of surgical cases. Short Abstract: The aim of the study is to determine whether seriate Risser casting associated with bracing is more effective in preventing curve progression than bracing alone in curves larger than 40°. This is a retrospective monocentric case−control study; we identified all the patients treated at our institution with a diagnosis of AIS, Risser grade 0−4 at the beginning of the treatment, at least one curve above 40° Cobb (35° if treated with bracing alone) and treatment with either seriate Risser casting and bracing (Study Group, SG) or bracing alone (Control Group, CG). Fifty-five patients (12 M, 43 F, mean age 13.5 ± 1.6) were included in the SG and 30 (5 M, 25 F, mean age 13.9 ± 1.7) in the CG. Eight (14,5%) patients in the SG failed the conservative treatment while fifteen (50%) failed in the CG. Consequently, the Relative Risk for progression in the Efficacy Analysis was 1.8 (95% CI 1.3−2.6, p = 0.001), and the Number Needed to Treat was 2,4. Seriate Risser casting for AIS with larger curves (>40°) is effective in reducing curve progression when compared with full time bracing alone. This type of treatment should be considered for AIS patients who present with large curves.
摘要：
背景：青少年特发性脊柱侧凸（AIS）最常见的保守治疗是支撑。然而,几篇论文质疑在40°和50°Cobb之间支撑曲线的有效性：防止曲线进展的有效性可低至35％。连续铸造被认为是早期脊柱侧凸的标准方法；但是，在AIS的设置中，铸造处理很少使用，只有很少的研究报告其有效性。研究目的：研究的主要目的是确定与支撑相关的Risser铸件的系列铸件在防止曲线发展方面是否比在大于40°的曲线中单独支撑更有效。此外，次要终点是：（1）胸椎（T）和胸腰/腰（TL/L）曲线之间的铸造效果是否存在差异？（2）“铸造”校正是否可以预测治疗结果？（3）铸造对胸椎后凸有什么影响？治疗开始时Risser等级在0到4之间，至少一条高于40°Cobb的曲线，并采用系列Risser铸造和支撑进行处理(研究组，SG)或单独支撑(控制组，CG）。在石膏治疗之前和之后获得AP和LL中的全脊柱X射线；对于每个制作的石膏，仅获得AP站立的全脊柱X射线。根据治疗结束时的曲线行为对患者进行分层（Risser5）：进展定义为曲线幅度或所需融合增加≥6°；稳定定义为曲线变化±5°；改善定义为曲线减少≥6°。结果：对于最终分析，55名患者(12M，43F,SG中包括平均年龄13.5±1.6)和27(4M，23F,CG的平均年龄13.6±1.6）。SG中的8例（14.5％）患者保守治疗失败，而CG中的14例（51.3％）失败。因此,疗效分析中的相对进展风险为1.8(95%CI1，3−2.6，p=0.001)，需要治疗的人数是2,4。关于“进行性”终点的T和TL/L曲线之间没有发现显著差异(z-评分0.263,p=0.79)。“铸造”曲线减少的平均百分比为40.1±15.2％；校正百分比与结果之间没有显着相关性（Spearman相关系数0.18）。最后,FUTK的基线和终点之间没有发现显着差异（32°±16.2vs.29.6±15.8，p=ns)。讨论：与治疗依从性患者中单独使用全时支具相比，具有较大曲线（>40°Cobb）的AIS的SeriateRiser铸造可有效降低曲线进展。该处理在控制T和TL/L曲线方面同样有效；此外，在接受铸型治疗的患者中,观察到TK有轻微但不显著的下降.对于出现大曲线的AIS患者，应考虑这种类型的治疗，以潜在地减少手术病例的百分比。摘要：该研究的目的是确定与支撑相关的系列Risser铸造是否比在大于40°的曲线中单独支撑更有效地防止曲线发展。这是一项回顾性单中心病例对照研究；我们确定了在我们机构接受治疗的所有患者诊断为AIS，治疗开始时的Risser等级0-4，至少一条超过40°Cobb的曲线(如果单独使用支撑处理,则为35°)以及使用系列Risser铸造和支撑处理(研究组,SG)或单独支撑(控制组，CG）。55名患者(12米，43F,平均年龄13.5±1.6)包括在SG和30(5M，25F,CG的平均年龄13.9±1.7）。SG中的8名（14,5％）患者保守治疗失败，而CG中的15名（50％）患者失败。因此,疗效分析中的相对进展风险为1.8(95%CI1.3−2.6，p=0.001)，需要治疗的人数是2,4。与单独的全时支撑相比，具有较大曲线（>40°）的AIS的连续Riser铸造可有效减少曲线的发展。对于出现大曲线的AIS患者，应考虑这种类型的治疗。
