Meier Malin, Janssen Dino, Koeck Franz Xaver, Thienpont Emmanuel, Beckmann Johannes, Best Raymond
Sportklinik Stuttgart, Taubenheimstraße 8, 70372, Stuttgart, Germany.
MedArtes Orthopaedic Surgery, Neutraubling, Germany.
Knee Surg Sports Traumatol Arthrosc. 2021 Mar;29(3):939-946. doi: 10.1007/s00167-020-06052-y. Epub 2020 May 10.
The primary objective of this study was to quantify the variations of the medial posterior tibial slope (MPTS) and the lateral posterior tibial slope (LPTS), as well as of the medial proximal tibial angle (MPTA), and to determine the fraction of patients for which standard techniques including different alignment techniques would result in alteration of the patient's individual posterior tibial slope (PTS) and MPTA. Furthermore, it was of interest if a positive correlation between PTS and MPTA or between medial and lateral slope exists.
A retrospective study was performed on CT-scans of 234 consecutively selected European patients undergoing individual total knee replacement. All measurements were done on three-dimensional CAD models, which were generated on the basis of individual CT-scans, including the hip, knee, and ankle center. Measurements included the medial and lateral PTS and the MPTA. PTS was measured as the angle between the patient's articular surface and a plane perpendicular to the mechanical axis of the tibia in the sagittal plane. MPTA was defined as the angle between the tibial mechanical axis and the proximal articular surface of the tibia in the coronal plane.
Analysis revealed a wide variation of the MPTS, LPTS, and MPTA among the patients. MPTS and LPTS varied significantly both interindividually and intraindividually. The range of PTS was up to 20° for MPTS (from - 4.3° to 16.8°) and for LPTS (from - 2.9 to 17.2°). The mean intraindividual difference between MPTS and LPTS in the same knee was 2.6° (SD 2.0) with a maximum of 9.5°. MPTA ranged from 79.8 to 92.1° with a mean of 86.6° (SD ± 2.4). Statistical analysis revealed a weak positive correlation between MPTA and MPTS.
The study demonstrates a huge interindividual variability in PTS and MPTA as well as significant intraindividual differences in MPTS and LPTS. Therefore, the question arises, whether the use of standard techniques, including fixed PTSs and MPTAs, is sufficient to address every single patient's individual anatomy.
III.
本研究的主要目的是量化胫骨后内侧斜率（MPTS）、胫骨后外侧斜率（LPTS）以及胫骨近端内侧角（MPTA）的变化，并确定包括不同对线技术在内的标准技术会导致患者个体胫骨后斜率（PTS）和MPTA改变的患者比例。此外，还关注PTS与MPTA之间或内侧与外侧斜率之间是否存在正相关。
对234例连续入选的接受个体化全膝关节置换术的欧洲患者的CT扫描进行回顾性研究。所有测量均在基于个体CT扫描生成的三维CAD模型上进行，包括髋、膝和踝关节中心。测量包括内侧和外侧PTS以及MPTA。PTS测量为患者关节面与矢状面中垂直于胫骨机械轴的平面之间的角度。MPTA定义为冠状面中胫骨机械轴与胫骨近端关节面之间的角度。
分析显示患者之间MPTS、LPTS和MPTA存在广泛差异。MPTS和LPTS在个体间和个体内均有显著差异。MPTS的PTS范围高达20°（从-4.3°到16.8°），LPTS的PTS范围为（从-2.9°到17.2°）。同一膝关节中MPTS和LPTS的个体内平均差异为2.6°（标准差2.0），最大差异为9.5°。MPTA范围为79.8°至92.1°，平均为86.6°（标准差±2.4）。统计分析显示MPTA与MPTS之间存在弱正相关。
该研究表明PTS和MPTA存在巨大的个体间变异性，以及MPTS和LPTS存在显著的个体内差异。因此，问题在于使用包括固定PTS和MPTA在内的标准技术是否足以适应每个患者的个体解剖结构。
III级。
