Vanin N, Kenaway M, Panzica M, Jagodzinski M, Meller R, Krettek C, Hankemeier S
Department of Traumatology, Hannover Medical School, Hannover, Germany.
Technol Health Care. 2010;18(4-5):335-40. doi: 10.3233/THC-2010-0598.
The accuracy of preoperative planning of the size of total knee arthroplasty (TKA) in literature is only 50%. A problem of conventional radiographic planning with prosthesis templates is varying enlargement of the radiographs. Digital planning and analysis of lower leg geometry revealed improved reliability compared to conventional techniques. The aim of the study was to evaluate the accuracy of digital planning of TKA with special planning software and calibrated radiographs and its interobserver reliability.
In a prospective study the sizes of 30 TKA were planned with special software by a senior and a junior surgeon independently. For calibration a 30 mm reference ball on the radiographs was used. The planning was compared with the intraoperative chosen size of the TKA.
The correlation of the planned femoral component with the chosen size was 87% for the senior and 77% for the junior surgeon. The planning of the tibial component revealed a correlation for the senior surgeon in 90% and for the junior surgeon in 87%. Both component was planned correctly in 77% by the senior and in 63% by the junior surgeon. In 50% the planning of both surgeons matched completely the used prosthesis sizes. The linear κ coefficient of Cohen revealed a good agreement (0.65) and a high interobserver reliability.
Planning TKA with special planning software with digital, calibrated radiographs is more accurate compared to previous conventional planning. The senior surgeons planning of both component sizes matched in 77% the correct size. Clinical experience improves the accuracy of preoperative planning.
文献中全膝关节置换术（TKA）术前假体尺寸规划的准确率仅为50%。使用假体模板进行传统X线片规划存在的一个问题是X线片放大率不一致。与传统技术相比，小腿几何结构的数字规划和分析显示出更高的可靠性。本研究的目的是评估使用特殊规划软件和校准X线片进行TKA数字规划的准确性及其观察者间的可靠性。
在一项前瞻性研究中，由一位资深外科医生和一位初级外科医生分别使用特殊软件独立规划30例TKA的假体尺寸。校准采用X线片上的一个30mm参考球。将规划结果与术中选择的TKA假体尺寸进行比较。
资深外科医生规划的股骨假体部件与所选尺寸的相关性为87%，初级外科医生为77%。胫骨假体部件的规划显示，资深外科医生的相关性为90%，初级外科医生为87%。资深外科医生对两个部件规划正确的比例为77%，初级外科医生为63%。两位外科医生的规划在50%的情况下与所使用的假体尺寸完全匹配。Cohen线性κ系数显示出良好的一致性（0.65）和较高的观察者间可靠性。
与以往的传统规划相比，使用特殊规划软件结合数字校准X线片进行TKA规划更为准确。资深外科医生对两个部件尺寸的规划与正确尺寸匹配的比例为77%。临床经验可提高术前规划的准确性。
