Institute for Surgical Technology and Biomechanics-ISTB, University of Bern, Stauffacherstr. 78, 3014 Bern, Switzerland.
Ann Biomed Eng. 2013 Oct;41(10):2077-87. doi: 10.1007/s10439-013-0822-6. Epub 2013 May 14.
The acquisition of conventional X-ray radiographs remains the standard imaging procedure for the diagnosis of hip-related problems. However, recent studies demonstrated the benefit of using three-dimensional (3D) surface models in the clinical routine. 3D surface models of the hip joint are useful for assessing the dynamic range of motion in order to identify possible pathologies such as femoroacetabular impingement. In this paper, we present an integrated system which consists of X-ray radiograph calibration and subsequent 2D/3D hip joint reconstruction for diagnosis and planning of hip-related problems. A mobile phantom with two different sizes of fiducials was developed for X-ray radiograph calibration, which can be robustly detected within the images. On the basis of the calibrated X-ray images, a 3D reconstruction method of the acetabulum was developed and applied together with existing techniques to reconstruct a 3D surface model of the hip joint. X-ray radiographs of dry cadaveric hip bones and one cadaveric specimen with soft tissue were used to prove the robustness of the developed fiducial detection algorithm. Computed tomography scans of the cadaveric bones were used to validate the accuracy of the integrated system. The fiducial detection sensitivity was in the same range for both sizes of fiducials. While the detection sensitivity was 97.96% for the large fiducials, it was 97.62% for the small fiducials. The acetabulum and the proximal femur were reconstructed with a mean surface distance error of 1.06 and 1.01 mm, respectively. The results for fiducial detection sensitivity and 3D surface reconstruction demonstrated the capability of the integrated system for 3D hip joint reconstruction from 2D calibrated X-ray radiographs.
传统 X 射线摄影仍然是诊断髋关节相关问题的标准成像程序。然而，最近的研究表明，在临床常规中使用三维（3D）表面模型是有益的。髋关节的 3D 表面模型可用于评估动态运动范围，以识别可能的病理学，如股骨髋臼撞击。在本文中，我们提出了一个集成系统，该系统包括 X 射线射线照相校准和随后的 2D/3D 髋关节重建，用于诊断和规划髋关节相关问题。开发了一个带有两个不同尺寸基准的移动体模用于 X 射线射线照相校准，可以在图像中稳健地检测到。基于校准的 X 射线图像，开发了一种髋臼的 3D 重建方法，并与现有的技术一起应用于重建髋关节的 3D 表面模型。使用干尸髋关节骨和一具软组织的尸体标本的 X 射线射线照相来证明所开发的基准检测算法的稳健性。使用尸体骨骼的计算机断层扫描来验证集成系统的准确性。两种基准尺寸的基准检测灵敏度相同。大基准的检测灵敏度为 97.96%，小基准的检测灵敏度为 97.62%。髋臼和近端股骨的重建表面距离误差平均值分别为 1.06 和 1.01 毫米。基准检测灵敏度和 3D 表面重建的结果表明，该集成系统具有从 2D 校准 X 射线射线照相重建 3D 髋关节的能力。
