■评估三维(3D)股骨头覆盖在评估中至关重要,术前计划,治疗髋关节发育不良.
■要(1)提出一种数学模型,以使用常规计算机断层扫描(CT)建立3D股骨头覆盖,(2)确定二维参数与三维覆盖率的相关性,和(3)基于3D形态学表征发育不良的模式。
■横断面研究;证据水平,3.
■我们确定了30例有症状的发育不良患者(n=髋部)和30例无发育不良患者(n=髋部)。髋关节发育不良的患者在性别方面是匹配的,年龄,和体重指数那些没有发育不良的臀部。术前CT采用3D软件分析,和3D股骨头表面积覆盖率(FHSAC;以%计)在4个象限区域进行评估:前内侧,前外侧,后内侧,和后外侧。为了评估股骨头的侧向覆盖,我们介绍了前外侧股骨头覆盖角(ALFC)和后外侧股骨头覆盖角(PLFC)。
■在前外侧象限中,与未发育异常的髋关节相比,股骨头覆盖率降低更为明显(18%vs40.7%,分别)和后外侧象限(35.8%和56.9%,分别)(两者的P<0.0001)。髋关节发育不良的ALFC和PLFC较小(18.4°vs38.7°;P<.0001;47.2°vs72.3°;P=.0002)。前外侧和后外侧FHSAC与ALFC(r=0.88;P<.0001)和PLFC(r=0.82;P<.0001)以及外侧中心边缘角(前外侧,r=0.75;P<0.0001;后外侧,r=0.73;P<.0001)。为FHSAC建立的预测模型与解释性CT变量非常吻合(前外侧:r=0.91;P<.0001;后外侧:r=0.90;P<.0001)。前外侧和后外侧FHSAC的截止值分别为25%和41%,分别。在发育不良的臀部,全球缺乏是最常见的(15/30臀部),9髋显示前外侧缺乏,4髋具有后外侧缺陷型。
■ALFC和PLFC与3D横向FHSAC密切相关,能够准确预测3D覆盖率。
UNASSIGNED: Assessment of 3-dimensional (3D) femoral head coverage is critical in evaluating, preoperative planning, and treating hip dysplasia.
UNASSIGNED: To (1) propose a mathematical model to establish 3D femoral head coverage using conventional computed tomography (CT), (2) determine the correlation of 2D parameters with 3D coverage, and (3) characterize the patterns of dysplasia based on 3D morphology.
UNASSIGNED: Cross-sectional study; Level of evidence, 3.
UNASSIGNED: We identified 30 patients (n = hips) with symptomatic dysplasia and 30 patients (n = hips) without dysplasia. Patients with dysplastic hips were matched with regard to sex, age, and body mass index to those with nondysplastic hips. Preoperative CTs were analyzed using 3D software, and 3D femoral head surface area coverage (FHSAC; in %) was assessed in 4 quadrant zones: anteromedial, anterolateral, posteromedial, and posterolateral. To assess lateral coverage of the femoral head, we introduced the anterolateral femoral head coverage angle (ALFC) and the posterolateral femoral head coverage angle (PLFC).
UNASSIGNED: Reduced femoral head coverage was more pronounced in dysplastic versus nondysplastic hips in the anterolateral quadrant (18% vs 40.7%, respectively) and posterolateral quadrant (35.8% vs 56.9%, respectively) (P < .0001 for both). Dysplastic hips had smaller ALFC and PLFC (18.4° vs 38.7°; P < .0001; 47.2° vs 72.3°; P = .0002). Anterolateral and posterolateral FHSAC were strongly correlated with the ALFC (r = 0.88; P < .0001) and the PLFC (r = 0.82; P < .0001) along with the lateral center-edge angle (anterolateral, r = 0.75; P < .0001; posterolateral, r = 0.73; P < .0001). Prediction models established for FHSAC had strong agreement with explanatory CT variables (anterolateral: r = 0.91; P < .0001; posterolateral: r = 0.90; P < .0001). The cutoff values for anterolateral and posterolateral FHSAC were 25% and 41%, respectively. In dysplastic hips, global deficiency was most common (15/30 hips), 9 hips showed an anterolateral deficiency, and 4 hips had a posterolateral deficiency pattern.
UNASSIGNED: The ALFC and The PLFC were strongly correlated with 3D lateral FHSAC and were able to predict 3D coverage accurately.