A computational simulation study to determine the biomechanical influence of posterior condylar offset and tibial slope in cruciate retaining total knee arthroplasty

Abstract

ObjectivesPosterior 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.MethodsWe 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.ResultsContact 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.ConclusionThe change in PCO alternatively provided positive and negative biomechanical effects, but it led to a reduction in a negative biomechanical effect as PTS increased.Cite this article: 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. Bone Joint Res 2018;7:69–78. DOI: 10.1302/2046-3758.71.BJR-2017-0143.R1.

Computational biomechanics of knee joint arthroplasty : a review

“…Higher quadriceps muscle and patellar tendon force are required as the posterior condylar offset moved in the anterior direction with an equivalent flexion angle. The forces exerted on the PCL increased as posterior condylar offset moved in the posterior direction (Kang, Koh, Son, Kwon, Lee and Kwon, 2018c). They found that change in posterior condylar offset alternatively provided positive and negative biomechanical effects.…”

“…7). Such studies have been performed in both FE and MBD models (Essner et al, 2011;Kang et al, 2018a;Kang et al, 2016;Kang et al, 2017f;Kang et al, 2018b;Kang et al, 2018c;Kang et al, 2018e;Kang et al, 2019b;Kang et al, 2018g;Kuriyama et al, 2014;Marra et al, 2018;Suh et al, 2017;Thompson et al, 2011). Investigations have included pre-or post-clinical evaluation for translation and rotation in coronal and sagittal planes.…”

“…Many studies related to the biomechanical effect were performed in terms of anterior-posterior misalignment in femoral component (Kang, Koh, Son, Kwon, Lee and Kwon, 2017f;Kang, Koh, Son, Kwon, Lee and Kwon, 2018c;Kang, Kwon, Kwon, Lee and Koh, 2019b;Kang, Kwon, Son, Kwon, Lee and Koh, 2018g). Kang et al found that contact stress on the patellar button increased and decreased as posterior condylar offset moved between the anterior and posterior directions, respectively.…”

Knieprothesendesign und Kinematik: Unterschiede in Radien, Konformität und Rotation/Pivot

“…2). Ein Verlust an posteriorem Kondylenoffset bedingt ein reduziertes femorales Rollback und kompromittiert damit die Beugefähigkeit und Stabilität [16,17]. Da trotz der angesprochenen Radiendifferenzen die konkreten Unterschiede der Femurgeometrien letztendlich im Millimeterbereich liegen, ist aufseiten des Femurs die akkurate Operationstechnik von entscheidenderer Bedeutung als das vorliegende Implantatdesign anzusehen.…”

Knee biomechanics

“…Kang et al 1 have ably demonstrated the role of finite element analysis (FEA) in deciphering the complex interplay between component positioning of the implanted total knee arthroplasty (TKA) and the kinetics of key soft-tissue structures. This work extends our knowledge of the role of the central posterior restraint (posterior cruciate ligament (PCL)) and the impact of varying posterior condylar offset (PCO) and posterior tibial slope upon final tibiofemoral flexion, muscle load, and by inference, final construct stability.…”