Objective: To evaluate the three-dimensional acetabular orientation in asymptomatic population and patients of developmental dysplasia of the hip (DDH) using a semi-automated measurement software, which provides data for the differential diagnosis, surgical planning, surgical instrument design, and postoperative evaluation of hip related diseases.
Methods: Eighty-four cases of CT data in asymptomatic population (asymptomatic group) and 47 cases of CT data in DDH patients (DDH group) were collected. There was no significant difference in gender and age (including age of male and female subgroups) between the two groups ( P<0.05). MaxTHA, a semi-automatic measurement software, was used to measure acetabular inclination and anteversion, including operative inclination (OI), radiographic inclination (RI), anatomic inclination (AI), operative anteversion (OA), radiographic anteversion (RA), and anatomic anteversion (AA). Comparisons were made between the two populations, between different Crowe classification subgroups, between different gender subgroups, and between left and right sides of acetabula.
Results: The comparison between asymptomatic group, healthy side of DDH group, and affected side of DDH group showed that there was no significant difference in acetabular orientation between asymptomatic group and healthy side of DDH group ( P>0.05). The OI, RI, and AI of affected side of DDH group were significantly higher than those in healthy side of DDH group and asymptomatic group, and AA was significantly lower than that in healthy side of DDH group and asymptomatic group ( P<0.05). The comparison between the normal acetabula and DDH acetabula with different Crowe classifications showed that there was no significant difference in the acetabulum orientation between Crowe Ⅰ group and the normal group ( P>0.05). The OI, RI, and AI of Crowe Ⅱ, Ⅲ, and Ⅳ groups were significantly higher than those of normal group ( P<0.05), the OI of Crowe Ⅲ group, RI and AI of Crowe Ⅳ group were significantly higher than those of Crowe Ⅰ group ( P<0.05), the AI of Crowe Ⅳ group was significantly higher than that of Crowe Ⅱ group ( P<0.05), and the OA, RA, and AA of Crowe Ⅲ group were significantly lower than other subgroups ( P<0.05) except Crowe Ⅰ group. The OA, RA, and AA in asymptomatic female group, and the OA and AI in DDH female group were significantly higher than those in all male groups ( P<0.05). The OI, RI, AI, and OA of the right acetabula in asymptomatic male group, and the RI and AI of the right acetabula in asymptomatic female group were significantly higher than those on the left side ( P<0.05).
Conclusion: There were significant differences in acetabular orientation between asymptomatic and DDH populations, inter-group differences among Crowe classification subgroups, inter-gender differences among subgroups, and bilateral differences among asymptomatic individuals.
目的: 比较分析无症状人群与发育性髋关节发育不良（developmental dysplasia of the hip，DDH）人群的髋臼三维朝向，为髋部疾病的鉴别诊断、手术规划、植入器械设计及术后评估等提供数据参考。.
方法: 回顾性收集符合选择标准的无症状人群骨盆CT 84例（无症状组）和DDH患者骨盆CT 47例（DDH组）。两组人群性别构成及年龄（包括男女亚组年龄）比较差异均无统计学意义（ P>0.05）。使用半自动测量软件MaxTHA测量3种定义下的前倾角和外展角，包括手术学外展角（operative inclination，OI）、影像学外展角（radiographic inclination，RI）、解剖学外展角（anatomic inclination，AI）、手术学前倾角（operative anteversion，OA）、影像学前倾角（radiographic anteversion，RA）和解剖学前倾角（anatomic anteversion，AA），并进行两人群间、不同Crowe分型亚组间、各性别亚组间及左右侧间的比较。.
结果: 无症状组与DDH组健、患侧间比较显示，无症状组与DDH组健侧的髋臼朝向各角度参数差异均无统计学意义（ P>0.05）；DDH组患侧的OI、RI、AI显著大于健侧和无症状组，AA显著小于健侧和无症状组，差异有统计学意义（ P<0.05）。正常髋臼与DDH组不同Crowe分型组间比较显示，Crowe Ⅰ型组与正常组髋臼朝向各角度参数比较差异均无统计学意义（ P>0.05）；Crowe Ⅱ、Ⅲ、Ⅳ型组OI、RI、AI显著大于正常组，Crowe Ⅲ型组的OI、Ⅳ型组的RI和AI显著大于Ⅰ型组，Ⅳ型组的AI显著大于Ⅱ型组（ P<0.05）；Crowe Ⅲ型组OA、RA、AA显著小于除Ⅰ型组外的各组（ P<0.05）。无症状组女性的OA、RA、AA以及DDH组女性的OA、AI显著大于对应组男性，差异有统计学意义（ P<0.05）。无症状组男性右侧髋臼的OI、RI、AI、OA以及女性右侧髋臼的RI、AI均显著大于左侧，差异有统计学意义（ P<0.05）。.
结论: 髋臼朝向在无症状人群和DDH人群间存在人群差异，在不同Crowe分型亚组间存在组间差异，在各人群亚组内存在性别间差异，在无症状人群中存在双侧差异。.
Keywords: Developmental dysplasia of the hip; acetabulum; anteversion; asymptomatic population; computer-assisted imaging processing; inclination.