强直性脊柱炎胸腹部折叠畸形程度的CT影像学分型及评估方法

Study on CT classification and evaluation methods for the degree of thoracoabdominal folded deformity in ankylosing spondylitis

中文关键词:  强直性脊柱炎  胸腰椎后凸畸形  胸腹部折叠畸形  胸腹折叠角  剑突-耻骨联合距离

英文关键词:Ankylosing spondylitis  Thoracolumbar kyphosis  Thoracoabdominal folded deformity  Thoracoabdominal folded angle  Distances between xiphoid process and superior edge of the pubis

中文摘要:

  【摘要】 目的：探讨强直性脊柱炎（ankylosing spondylitis，AS）胸腹部折叠畸形的CT影像学分型及评估方法。方法：回顾性分析2017年7月～2024年1月31例行胸腰椎CT检查的AS胸腰椎后凸畸形患者资料，男28例，女3例，平均年龄45.0±8.9岁。在胸腰椎CT正中矢状面上测量胸腹折叠角（thoracoabdominal folded angle，TAFA）及剑突-耻骨联合距离（the distances between xiphoid process and superior edge of the pubis，XP），同时在脊柱全长侧位片上测量全脊椎后凸Cobb角（global kyphosis，GK）、胸椎后凸Cobb角（thoracic kyphosis，TK）、腰椎前凸Cobb角（lumbar lordosis，LL）及矢状面躯干偏移（sagittal vertical axis，SVA）。根据CT矢状面腰椎生理曲度对腹腔容积变化的影响创新性提出AS胸腹部折叠畸形的CT影像学分型，腰椎存在生理前凸时为Ⅰ型，腰椎生理曲度变直时为Ⅱ型，腰椎后凸畸形时为Ⅲ型。根据TAFA将Ⅲ型患者分为两个亚型，TAFA＞90°为A亚型，TAFA≤90°为B亚型。由5名经过培训的脊柱外科医师先后对患者的临床资料进行独立评估与分型（间隔10d），采用Kendall′s W检验分析多组观察结果的一致性。采用单因素方差分析检验比较各型间上述测量参数的差异性。结果：31例患者中，胸腹部折叠畸形Ⅰ型5例、Ⅱ型8例、ⅢA型12例、ⅢB型6例。观察者间分型Kendall′s W一致性系数为0.954（P＜0.001）。患者平均GK、TK、LL、SVA、TAFA及XP分别为83.7°±29.9°、48.7°±21.3°、-13.9°±25.3°、22.8±14.9cm、128.1°±50.5°及16.8±8.9cm；各组TAFA、XP测量数值间Kendall′s W一致性系数分别为0.946（P＜0.001）和0.979（P＜0.001）；各分型间TAFA及XP两两比较均具有显著性差异（P＜0.001）。结论：CT影像学分型可以客观评价AS胸腹部折叠畸形情况，剑突-耻骨联合距离及胸腹折叠角是评估AS胸腹部折叠畸形的重要指标。

英文摘要:

  【Abstract】 Objectives: To explore the CT classification and evaluation methods of thoracoabdominal folded deformity in ankylosing spondylitis(AS). Methods: A retrospective analysis was conducted on 31 patients with AS thoracolumbar kyphosis who underwent thoracolumbar CT examinations between July 2017 and January 2024. There were 28 males and 3 females, with an average age of 45.0±8.9 years. The thoracoabdominal folded angle(TAFA) and the distances between xiphoid process and the superior edge of the pubic symphysis(XP) were measured on the mid-sagittal plane of thoracolumbar CT. The global kyphosis(GK), thoracic kyphosis(TK), and lumbar lordosis(LL) Cobb angle and sagittal vertical axis(SVA) were measured on the full-length lateral radiograph of the spine. According to the effect of sagittal lumbar physiological curvature on the change of abdominal volume, a CT classification of AS thoracoabdominal folded deformity was innovatively classified into three types, type I when there was physiological lordosis in the lumbar spine, type Ⅱ when the physiological curvature of the lumbar spine became straight, and type Ⅲ when there was lumbar kyphosis deformity. According to TAFA, type Ⅲ patients were divided into two subtypes: TAFA>90° was subtype A, and TAFA≤90° was subtype B. Five trained spinal surgeons independently evaluated and classified the clinical data of patients(with a 10d interval), and used Kendall′s W-test to analyze the consistency of multiple observation results. Using one-way analysis of variance to compare the differences in the above measurement parameters between different types. Results: Among the 31 patients, there were 5 cases of thoracoabdominal folded deformity type Ⅰ, 8 cases of type Ⅱ, 12 cases of type ⅢA, and 6 cases of type ⅢB. The Kendall′s W consistency coefficient for inter-observer classification was 0.954(P<0.001). The average GK, TK, LL, SVA, TAFA, and XP of patients were 83.7°±29.9°, 48.7°±21.3°, -13.9°±25.3°, 22.8±14.9cm, 128.1°±50.5°, and 16.8±8.9cm, respectively; The Kendall′s W consistency coefficients between the different groups′ measurement values of TAFA and XP were 0.946(P<0.001) and 0.979(P<0.001), respectively; There were significant differences in TAFA and XP pairwise comparisons between different subtypes(P<0.001). Conclusions: CT imaging classification can objectively evaluate the thoracoabdominal folded deformity in AS, and the distance between the xiphoid process and pubic symphysis and the TAFA are important indicators for evaluating the thoracoabdominal folded deformity in AS.