Kang K-T, Koh Y-G, Son J, Kwon O-R, Lee J-S, Kwon S K
Department of Mechanical Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, South Korea.
Joint Reconstruction Center, Department of Orthopaedic Surgery, Yonsei Sarang Hospital, 10 Hyoryeong-ro, Seocho-gu, Seoul 06698, South Korea.
Bone Joint Res. 2018 Jan;7(1):69-78. doi: 10.1302/2046-3758.71.BJR-2017-0143.R1.
Posterior condylar offset (PCO) and posterior tibial slope (PTS) are critical factors in total knee arthroplasty (TKA). A computational simulation was performed to evaluate the biomechanical effect of PCO and PTS on cruciate retaining TKA.
We generated a subject-specific computational model followed by the development of ± 1 mm, ± 2 mm and ± 3 mm PCO models in the posterior direction, and -3°, 0°, 3° and 6° PTS models with each of the PCO models. Using a validated finite element (FE) model, we investigated the influence of the changes in PCO and PTS on the contact stress in the patellar button and the forces on the posterior cruciate ligament (PCL), patellar tendon and quadriceps muscles under the deep knee-bend loading conditions.
Contact stress on the patellar button increased and decreased as PCO translated to the anterior and posterior directions, respectively. In addition, contact stress on the patellar button decreased as PTS increased. These trends were consistent in the FE models with altered PCO. Higher quadriceps muscle and patellar tendon force are required as PCO translated in the anterior direction with an equivalent flexion angle. However, as PTS increased, quadriceps muscle and patellar tendon force reduced in each PCO condition. The forces exerted on the PCL increased as PCO translated to the posterior direction and decreased as PTS increased.
The change in PCO alternatively provided positive and negative biomechanical effects, but it led to a reduction in a negative biomechanical effect as PTS increased.: K-T. Kang, Y-G. Koh, J. Son, O-R. Kwon, J-S. Lee, S. K. Kwon. A computational simulation study to determine the biomechanical influence of posterior condylar offset and tibial slope in cruciate retaining total knee arthroplasty. 2018;7:69-78. DOI: 10.1302/2046-3758.71.BJR-2017-0143.R1.
后髁偏移（PCO）和胫骨后倾（PTS）是全膝关节置换术（TKA）中的关键因素。进行了一项计算机模拟，以评估PCO和PTS对保留交叉韧带的TKA的生物力学影响。
我们生成了一个特定于个体的计算模型，随后向后分别开发了±1 mm、±2 mm和±3 mm的PCO模型，以及与每个PCO模型对应的-3°、0°、3°和6°的PTS模型。使用经过验证的有限元（FE）模型，我们研究了在深屈膝加载条件下，PCO和PTS的变化对髌骨按钮处的接触应力以及后交叉韧带（PCL）、髌腱和股四头肌上的力的影响。
随着PCO向前和向后移动，髌骨按钮上的接触应力分别增加和减小。此外，随着PTS增加，髌骨按钮上的接触应力减小。这些趋势在PCO改变的FE模型中是一致的。在相同的屈曲角度下，随着PCO向前移动，需要更高的股四头肌和髌腱力。然而，随着PTS增加，在每种PCO条件下，股四头肌和髌腱力都会降低。随着PCO向后移动，作用于PCL的力增加，随着PTS增加而减小。
PCO的变化交替产生正向和负向生物力学效应，但随着PTS增加，它导致负向生物力学效应的降低。：K-T. Kang、Y-G. Koh、J. Son、O-R. Kwon、J-S. Lee、S. K. Kwon。一项确定后髁偏移和胫骨斜率在保留交叉韧带全膝关节置换术中生物力学影响的计算机模拟研究。2018年；7：69 - 78。DOI：10.1302/2046 - 3758.71.BJR - 2017 - 0143.R1。
