Miyasaka Dai, Ito Tomoyuki, Imai Norio, Suda Ken, Minato Izumi, Dohmae Yoichiro, Endo Naoto
Division of Orthopaedic Surgery, Department of Regenerative and Transplant Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata 951-8510,
Acta Med Okayama. 2014;68(5):277-84. doi: 10.18926/AMO/52896.
The acetabular coverage of the femoral head has been assessed in two-dimensions as the projected covered area or the covered angle on plain radiographs. We present a novel method of the three-dimensional assessment of femoral head coverage obtained by evaluating the covered volume of the femoral head in both normal and dysplastic hips. We also assessed the covered angles on the vertical slices passing through the center of the femoral head. The mean covered volume of the femoral head was 57.4% in normal hips and 26.6% in dysplastic hips. In dysplastic hips, the L-CE, A-CE, and P-CE angles were 7.7°, 21.8°, and 95.8°, respectively, while the acetabular angle was 27.5°. In normal hips, the CE angles were 34.0°, 56.8°, and 109.4°, respectively, while the acetabular angle was 7.2°. Our study suggests the usefulness of a novel 3D assessment for acetabular coverage of the femoral head. This assessment provided the precise 3D information necessary to diagnose hip dysplasia and assess the deficiency of acetabular coverage in these patients. Moreover, we may detect a cut-off between normal and dysplastic hips in the 3D assessment by assessing a large number of dysplastic hips both morphologically and using the new assessment.
股骨头的髋臼覆盖情况已在二维平面上通过X线平片上的投影覆盖面积或覆盖角度进行评估。我们提出了一种通过评估正常和发育异常髋关节中股骨头的覆盖体积来进行股骨头覆盖情况三维评估的新方法。我们还评估了穿过股骨头中心的垂直切片上的覆盖角度。正常髋关节中股骨头的平均覆盖体积为57.4%，发育异常髋关节中为26.6%。在发育异常髋关节中，外侧中心边缘（L-CE）角、前侧中心边缘（A-CE）角和后侧中心边缘（P-CE）角分别为7.7°、21.8°和95.8°，而髋臼角为27.5°。在正常髋关节中，CE角分别为34.0°、56.8°和109.4°，而髋臼角为7.2°。我们的研究表明这种新的三维评估方法对于股骨头髋臼覆盖情况是有用的。该评估提供了诊断髋关节发育不良和评估这些患者髋臼覆盖不足所需的精确三维信息。此外，通过对大量发育异常髋关节进行形态学评估并使用新的评估方法，我们可能在三维评估中检测出正常与发育异常髋关节之间的界限。
