青少年特发性脊柱侧凸患者支具治疗后功能性动作特征及疗效影响因素列线图预测模型的建立

Characteristics of functional movements after brace treatment for adolescent idiopathic scoliosis and development of a nomogram prediction model of factors influencing efficacy

中文关键词:  青少年特发性脊柱侧凸  支具治疗  功能性动作特征  侧凸进展

英文关键词:Adolescent idiopathic scoliosis  Brace therapy  Functional action characteristics  Scoliosis progression

中文摘要:

  【摘要】 目的：分析青少年特发性脊柱侧凸（adolescent idiopathic scoliosis，AIS）患者支具治疗后功能性动作特征，建立并验证列线图模型预测疗效不佳风险。方法：收集2020年3月~2022年3月在我院行支具治疗的AIS患者作训练集，治疗前、初次随访时和治疗后均行功能性动作测试；同标准收集2022年4月～2022年8月在我院行支具治疗的AIS患者为验证集。根据治疗1年后侧凸进展度数是否＞5°将训练集患者分为稳定组（≤5°）和进展组（＞5°），比较组间资料；采用Spearman相关性分析法分析变量间的相关性；采用Logistic回归模型筛选疗效不佳的危险因素；应用R软件建立列线图预测模型，以受试者操作特征（receiver operating characteristic，ROC）曲线下面积（area under curve，AUC）和校准曲线评价该模型的区分度与准确性。以训练集Bootstrap自抽样前后预测风险值为检验变量、患者实际预后情况为状态变量进行内部验证；验证集Bootstrap自抽样随机化后对模型进行外部验证。结果：训练集共纳入AIS患者102例，稳定组73例，进展组29例（侧凸进展8°~27°），中位随访时间15.4个月；治疗后胸、腰Cobb角均显著性下降（P＜0.05）；初次随访时旋动稳定性、俯卧撑评分高于治疗前，治疗后弓步蹲、跨栏、旋动稳定性、俯卧撑项目评分提高（P＜0.05）；功能性动作特征与Cobb角度无显著相关性（P＞0.05）。治疗前Cobb角≥35°、Risser征≥3级、顶椎旋转度≥Ⅲ度、脊柱长度增速≥20mm/年是侧凸进展的独立危险因素，腰椎骨密度≥0.8g/cm2、脊柱柔韧性≥50%是保护因素。列线图预测支具治疗后侧凸进展的风险总值为0.93。训练集自抽样前后AUC分别为0.928（95%CI：0.858~0.998）和0.926（95%CI：0.854~0.997）。验证集共纳入37例患者，验证集外部验证AUC为0.891（95%CI：0.857~0.998）。校准曲线均显示拟合度较好。结论：AIS患者因脊柱受限而存在运动模式不良，支具治疗可提升躯干稳定性和旋动稳定性，对患者运动模式有良好的校正作用。治疗前Cobb角≥35°、Risser征≥3级、顶椎旋转度≥Ⅲ度、脊柱长度增速≥20mm/年、腰椎骨密度＜0.8g/cm2、脊柱柔韧性＜50%的AIS患者行支具治疗易发生侧凸进展，应基于列线图模型及时预警，并在合适时机辅以体态纠正，以改善AIS支具治疗预后。

英文摘要:

  【Abstract】 Objectives: To analyze the functional movement characteristics after brace treatment for patients with adolescent idiopathic scoliosis(AIS), and to develop and validate a nomogram model to predict the risk of poor outcome. Methods: AIS patients who were treated with braces at our institution from March 2020 to March 2022 were collected as a training set, and were tested for functional movement before treatment, at initial follow-up and after treatment. The same criteria were used to collect AIS patients who underwent brace treatment in our hospital from April 2022 to August 2022 as the validation set. On the basis of whether the degree of scoliosis progression was >5° after 1 year of treatment, the patients in the training set were divided into stable(≤5°) and progressive(>5°) groups. Comparison of data was made between groups. Spearman correlation analysis was used to analyze the correlation between variables. Logistic regression model was used to screen the risk factors for poor outcomes. R software was applied to develop a nomogram prediction model. Area under curve(AUC) of receiver operating characteristic(ROC) curve and calibration curve were applied to evaluate the discrimination and accuracy of the model. Internal validation was performed with the model predicted risk values before and after training set Bootstrap self-sampling as the test variables and the actual prognosis of patients as the state variable; External validation of the model was performed after randomization of the validation set Bootstrap self-sampling. Results: A total of 102 patients with AIS were included in the training set. There were 73 cases in the stable group and 29 cases in the progressive group(range of degrees of progression: 8° to 27°). The median follow-up time was 15.4 months. Both thoracic and lumbar Cobb angles decreased significantly after treatment(P<0.05). Rotational stability and push-ups were higher at initial follow-up than before treatment, and scores on bow-step squat, hurdle striding, rotational stability, and push-ups improved after treatment(P<0.05). There was no significant correlation between functional movement characteristics and Cobb angle(P>0.05). Pre-treatment Cobb angle≥35°, Risser′s sign≥3°, apex rotation≥degree Ⅲ, and spinal length gain≥20mm/year were independent risk factors for scoliosis progression. Lumbar spine bone density≥0.8g/cm2 and spinal flexibility≥50% were protective factors. The total value of the risk of scoliosis progression after brace treatment predicted by the nomogram model was 0.93. The AUCs before and after training set self-sampling were 0.928(95% CI: 0.858-0.998) and 0.926(95% CI: 0.854-0.997), respectively. The validation set included 37 patients. The external validation AUC for validation set was 0.891(95% CI: 0.857-0.998). The calibration curves all showed good degree of fitting. Conclusions: Patients with AIS have poor movement patterns due to spinal restrictions. Brace treatment improves trunk stability and rotational stability, which has good corrective effects on the movement pattern. AIS patients with Cobb angle≥35°, Risser′s sign≥3°, apex rotation≥degree Ⅲ, spinal length gain≥20mm/year, lumbar spine bone mineral density<0.8g/cm2, and spinal flexibility<50% before treatment who underwent bracing are prone to scoliosis progression. Timely warning shall be made based on the nomogram model and postural correction needs to be supplemented at appropriate time to improve the prognosis of AIS brace treatment.