Okazaki Ken, Tashiro Yasutaka, Mizu-uchi Hideki, Hamai Satoshi, Doi Toshio, Iwamoto Yukihide
Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
Knee. 2014 Aug;21(4):806-9. doi: 10.1016/j.knee.2014.02.019. Epub 2014 Feb 28.
Adjusting the joint gap length to be equal in both extension and flexion is an important issue in total knee arthroplasty (TKA). It is generally acknowledged that posterior tibial slope affects the flexion gap; however, the extent to which changes in the tibial slope angle directly affect the flexion gap remains unclear. This study aimed to clarify the influence of tibial slope changes on the flexion gap in cruciate-retaining (CR) or posterior-stabilizing (PS) TKA.
The flexion gap was measured using a tensor device with the femoral trial component in 20 cases each of CR- and PS-TKA. A wedge plate with a 5° inclination was placed on the tibial cut surface by switching its front-back direction to increase or decrease the tibial slope by 5°. The flexion gap after changing the tibial slope was compared to that of the neutral slope measured with a flat plate that had the same thickness as that of the wedge plate center.
When the tibial slope decreased or increased by 5°, the flexion gap decreased or increased by 1.9 ± 0.6mm or 1.8 ± 0.4mm, respectively, with CR-TKA and 1.2 ± 0.4mm or 1.1 ± 0.3mm, respectively, with PS-TKA.
The influence of changing the tibial slope by 5° on the flexion gap was approximately 2mm with CR-TKA and 1mm with PS-TKA.
This information is useful when considering the effect of manipulating the tibial slope on the flexion gap when performing CR- or PS-TKA.
在全膝关节置换术（TKA）中，使关节间隙长度在伸直和屈曲时相等是一个重要问题。一般认为胫骨后倾角度会影响屈曲间隙；然而，胫骨倾斜角度的变化直接影响屈曲间隙的程度仍不清楚。本研究旨在阐明胫骨倾斜度变化对保留交叉韧带（CR）或后稳定型（PS）TKA屈曲间隙的影响。
在20例CR-TKA和20例PS-TKA中，使用带有股骨试验组件的张量装置测量屈曲间隙。通过改变楔形板的前后方向，将一个倾斜5°的楔形板放置在胫骨截骨面上，使胫骨倾斜度增加或减少5°。将改变胫骨倾斜度后的屈曲间隙与使用与楔形板中心厚度相同的平板测量的中立倾斜度时的屈曲间隙进行比较。
当胫骨倾斜度减少或增加5°时，CR-TKA的屈曲间隙分别减少或增加1.9±0.6mm或1.8±0.4mm，PS-TKA的屈曲间隙分别减少或增加1.2±0.4mm或1.1±0.3mm。
在CR-TKA中，胫骨倾斜度改变5°对屈曲间隙的影响约为2mm，在PS-TKA中约为1mm。
在进行CR或PS-TKA时，考虑调整胫骨倾斜度对屈曲间隙的影响时，该信息很有用。
