Study on CT classification and evaluation methods for the degree of thoracoabdominal folded deformi-ty in ankylosing spondylitis
10.3969/j.issn.1004-406X.2025.01.02
- VernacularTitle: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
- Author:
Wen YIN
1
;
Xilong CUI
1
;
Wei ZHANG
1
Author Information
1. 安徽医科大学附属阜阳人民医院骨科 安徽省脊柱畸形临床医学研究中心 236000 阜阳市
- Publication Type:Journal Article
- Keywords:
Ankylosing spondylitis;
Thoracolumbar kyphosis;
Thoracoabdominal folded deformity;
Thoracoab-dominal folded angle;
Distances between xiphoid process and superior edge of the pubis
- From:
Chinese Journal of Spine and Spinal Cord
2025;35(1):12-20
- CountryChina
- Language:Chinese
-
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 kypho-sis(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 clini-cal 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 Ⅲ A,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,SV A,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 differ-ences 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 thoracoab-dominal folded deformity in AS.