White S P, Shardlow D L
Department of Orthopaedics, Yeovil District Hospital, Yeovil, Somerset, UK.
Ann R Coll Surg Engl. 2005 Jan;87(1):53-4. doi: 10.1308/1478708051540.
To assess whether the introduction of digital radiographic acquisition has altered the magnification of pelvic radiographs compared to standard acquisition techniques, and whether this influences preoperative implant templating for total hip arthroplasty.
District general hospital orthopaedic out-patient department.
51 sets of patient radiographs were studied, where digital and standard radiographic techniques had been used for each patient. Key bony landmarks were measured, the scaled ruler analysed and the femur templated to gauge the most appropriate implant size of implant.
Introduction of digital techniques has resulted in a mean magnification of 97%, whereas most manufacturers' templates assume a magnification of 115-120%. For the Exeter femoral component, the templated size showed only moderate correlation with that templated from a standard radiograph (kappa index 0.46), although the offset templated showed good correlation (kappa index 0.89).
Surgeons should be aware that introduction of digital techniques of radiograph acquisition may reduce the magnification of the film and, therefore, reduce the accuracy of pre-operative templates supplied by the manufacturers of implants, resulting in incorrect selection of implants.
评估与标准采集技术相比，数字放射成像采集的引入是否改变了骨盆X线片的放大率，以及这是否会影响全髋关节置换术前的植入物模板测量。
地区综合医院骨科门诊。
研究了51组患者的X线片，每位患者均采用了数字和标准放射成像技术。测量关键骨性标志，分析比例尺并对股骨进行模板测量以确定最合适的植入物尺寸。
数字技术的引入导致平均放大率为97%，而大多数制造商的模板假设放大率为115 - 120%。对于埃克塞特股骨假体，模板测量尺寸与标准X线片测量尺寸仅呈中度相关（kappa指数0.46），尽管模板测量的偏移量显示出良好的相关性（kappa指数0.89）。
外科医生应意识到，数字放射成像采集技术的引入可能会降低胶片的放大率，从而降低植入物制造商提供的术前模板的准确性，导致植入物选择错误。
