Gravius S, Belei P, de la Fuente M, Radermacher K, Mumme T
Department of Orthopaedic Surgery and Traumatology, Rheinische-Friedrich-Wilhelms University, Bonn, Germany.
Proc Inst Mech Eng H. 2010;224(4):565-76. doi: 10.1243/09544119JEIM629.
Prosthesis-specific mechanical alignment instruments for the precise and reproducible positioning of the femoral component constitute one of the major improvements in modern hip resurfacing prostheses. However, mechanical failure of the femoral component is mostly attributable to the surgical technique, and in particular to notching of the femoral neck. In order to evaluate a novel computer-assisted fluoroscopy-based planning and navigation system, six DUROM hip resurfacing prostheses were implanted into artificial femurs by means of computer-assisted fluoroscopy-based navigation and prosthesis-specific mechanical alignment instruments. Subsequently, the planning and navigation system was tested within the scope of a cadaver study on three fixed whole-body preparations (six femurs). The average difference between planned and actual angle of the prosthesis was 0 +/- 0.7 degrees for fluoroscopy-based navigation versus 6.5 +/- 7.8 degrees for the in-vitro use of the prosthesis-specific mechanical alignment instruments, and 1 +/- 1.4 degrees for fluoroscopic navigation in the cadaver study. The average discrepancy between planned and actual anterior offset was -1.2 +/- 1.2 mm versus 0.8 +/- 4 mm, and 0.3 +/- 2.2 mm in the cadaver study, and the time required for the total of five planning and navigation steps was 17.2 +/- 1.5 min versus 14 +/- 0.8 min and 20.2 +/- 2.5 min respectively. No notching of the femoral neck occurred under fluoroscopy nor under conventional treatment. During in-vitro studies, use of the computer-assisted fluoroscopy-based planning and navigation system resulted in enhanced accuracy compared with conventional prosthesis-specific mechanical alignment instruments. The system has yielded initial promising results within the scope of the cadaver study.
用于股骨部件精确且可重复定位的特定假体机械对线器械是现代髋关节表面置换假体的主要改进之一。然而，股骨部件的机械故障大多归因于手术技术，尤其是股骨颈开槽。为了评估一种基于计算机辅助透视的新型规划和导航系统，通过基于计算机辅助透视的导航和特定假体机械对线器械，将六个DUROM髋关节表面置换假体植入人工股骨。随后，在一项尸体研究范围内，在三个固定的全身标本（六个股骨）上对该规划和导航系统进行了测试。基于透视的导航中，假体计划角度与实际角度的平均差值为0±0.7度，而体外使用特定假体机械对线器械时为6.5±7.8度，尸体研究中透视导航时为1±1.4度。计划和实际前倾角的平均差异分别为-1.2±1.2毫米、0.8±4毫米和尸体研究中的0.3±2.2毫米，五个规划和导航步骤总共所需时间分别为17.2±1.5分钟、14±0.8分钟和20.2±2.5分钟。透视检查和传统治疗下均未出现股骨颈开槽情况。在体外研究中，与传统的特定假体机械对线器械相比，使用基于计算机辅助透视的规划和导航系统提高了准确性。该系统在尸体研究范围内已取得初步的良好结果。
