Effects of posterior condylar offset and posterior tibial slope on mobile-bearing total knee arthroplasty using computational simulation

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.

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Posterior tibial slope is a modifiable predictor of relatively large extension gaps in total knee arthroplasty for degenerative osteoarthritis

Journal of Orthopaedic Surgery ◽

10.1177/23094990211002004 ◽

2021 ◽

Vol 29 (1) ◽

pp. 230949902110020

Author(s):

Kyun-Ho Shin ◽

Sang-Bum Kim ◽

Ki-Mo Jang ◽

Chul-Soo Lee ◽

Seung-Beom Han

Keyword(s):

Total Knee Arthroplasty ◽

Knee Arthroplasty ◽

Tibial Slope ◽

Joint Line ◽

Posterior Tibial Slope ◽

Weighting Method ◽

Posterior Tibial ◽

Posterior Condylar ◽

Total Knee ◽

Extension Gap

Background: During total knee arthroplasty (TKA) for osteoarthritis, the sagittal gap imbalance (SGI) with a relatively large extension gap is an important surgical challenge. We determined the predictors of SGI with a relatively large extension gap and evaluated the surgical outcomes of knees with SGI. Methods: 551 consecutive cases of primary TKA for osteoarthritis were retrospectively reviewed. The cohort was divided into two groups according to the SGI and statistically matched according to baseline characteristics via the inverse probability of treatment weighting method. Multiple linear and logistic regression analyses were performed to determine the predictors of sagittal gap difference (SGD) and SGI. Intergroup differences in clinical and radiological outcomes were analyzed. Results: Of all the knees included, 8.5% (n = 45) presented with SGI with a relatively large extension gap and required femoral sagittal balancing to manage SGI. The hyperextension angle (HA), preoperative joint line convergence angle (JLCA), and the change in posterior tibial slope (PTS) significantly correlated to SGD and predicted SGI with a relatively large extension gap. SGI group showed significant changes in femoral posterior condylar offset and joint line height compared to those without SGI (1.48 vs −0.45, 1.37 vs −0.51, respectively). Postoperative ROM and knee society knee scores were lower in SGI group. Conclusion: Knees requiring sagittal balancing to manage SGI with a relatively large extension gap is not uncommon in TKA for osteoarthritic knees. The change in PTS is an independent and modifiable predictor of SGI.

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The posterior tibial slope does not influence the flexion angle in posterior-stabilized mobile-bearing total knee arthroplasty

Arthroplasty ◽

10.1186/s42836-021-00085-5 ◽

2021 ◽

Vol 3 (1) ◽

Author(s):

Susumu Takemura ◽

Tessyu Ikawa ◽

Yohei Ohyama ◽

Mitsunari Kim ◽

Kunio Takaoka ◽

...

Keyword(s):

Total Knee Arthroplasty ◽

Knee Arthroplasty ◽

Primary Total Knee Arthroplasty ◽

Mobile Bearing ◽

Tibial Slope ◽

Flexion Angle ◽

Posterior Tibial Slope ◽

Posterior Stabilized ◽

Posterior Tibial ◽

Total Knee

Abstract Background It remains uncertain whether an increase in the tibial slope leads to better flexion in posterior-stabilized (PS) total knee prostheses. Purpose To compare the intra-operative flexion angle between standard and an additional 10° posterior slope inserts. Patients and methods Between December 2014 and February 2015, 22 patients (25 knees) who underwent PS mobile-bearing primary total knee arthroplasty (TKA) were included. Flexion angles were measured using either standard or specially-made inserts. Differences in flexion angles between the two situations were analyzed to determine the relationship between changes in flexion angle and pre-operative flexion angle or body mass index (BMI), and between intra- and post-operative flexion angle. Results The difference between the average flexion angle of standard inserts and specially-made inserts was not statistically significant. Although the correlations between changes in flexion angle due to insert difference and flexion angle, pre-operative flexion angle or BMI were not significant, there was a positive correlation between intra-operative and post-operative flexion at 2 years. Conclusion The results showed an additional posterior tibial slope by 10° did not affect the intra-operative flexion angle. Surgeons performing PS mobile-bearing TKA do not need to excessively slope the tibial bone cutting to improve the post-operative flexion angle. Level of evidence I, Experimental study.

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Influence of Increased Posterior Tibial Slope in Total Knee Arthroplasty on Knee Joint Biomechanics: A Computational Simulation Study

The Journal of Arthroplasty ◽

10.1016/j.arth.2017.09.025 ◽

2018 ◽

Vol 33 (2) ◽

pp. 572-579 ◽

Cited By ~ 29

Author(s):

Kyoung-Tak Kang ◽

Yong-Gon Koh ◽

Juhyun Son ◽

Oh-Ryong Kwon ◽

Jun-Sang Lee ◽

...

Keyword(s):

Total Knee Arthroplasty ◽

Knee Joint ◽

Knee Arthroplasty ◽

Simulation Study ◽

Computational Simulation ◽

Tibial Slope ◽

Posterior Tibial Slope ◽

Posterior Tibial ◽

Joint Biomechanics ◽

Total Knee

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Biomechanical Effects of Posterior Condylar Offset and Posterior Tibial Slope on Quadriceps Force and Joint Contact Forces in Posterior-Stabilized Total Knee Arthroplasty

BioMed Research International ◽

10.1155/2017/4908639 ◽

2017 ◽

Vol 2017 ◽

pp. 1-12 ◽

Cited By ~ 4

Author(s):

Kyoung-Tak Kang ◽

Yong-Gon Koh ◽

Juhyun Son ◽

Oh-Ryong Kwon ◽

Jun-Sang Lee ◽

...

Keyword(s):

Total Knee Arthroplasty ◽

Contact Stress ◽

Knee Arthroplasty ◽

Tibial Slope ◽

Posterior Stabilized ◽

Posterior Condylar Offset ◽

Posterior Tibial ◽

Posterior Condylar ◽

Total Knee ◽

Quadriceps Force

This study aimed to determine the biomechanical effect of the posterior condylar offset (PCO) and posterior tibial slope (PTS) in posterior-stabilized (PS) fixed-bearing total knee arthroplasty (TKA). We developed ±1, ±2, and ±3 mm PCO models in the posterior direction and −3°, 0°, 3°, and 6° PTS models using a previously validated FE model. The influence of changes in the PCO and PTS on the biomechanical effects under deep-knee-bend loading was investigated. The contact stress on the PE insert increased by 14% and decreased by 7% on average as the PCO increased and decreased, respectively, compared to the neutral position. In addition, the contact stress on post in PE insert increased by 18% on average as PTS increased from −3° to 6°. However, the contact stress on the patellar button decreased by 11% on average as PTS increased from −3° to 6° in all different PCO cases. The quadriceps force decreased by 14% as PTS increased from −3° to 6° in all PCO models. The same trend was found in patellar tendon force. Changes in PCO had adverse biomechanical effects whereas PTS increase had positive biomechanical effects. However, excessive PTS should be avoided to prevent knee instability and subsequent failure.

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Effect of Posterior Tibial Slope Change on Postoperative Range of Motion and Clinical Outcomes after Posterior Cruciate-Substituting Total Knee Arthroplasty

The Journal of Knee Surgery ◽

10.1055/s-0041-1729967 ◽

2021 ◽

Author(s):

O-Sung Lee ◽

Jangyun Lee ◽

Myung Chul Lee ◽

Hyuk-Soo Han

Keyword(s):

Total Knee Arthroplasty ◽

Range Of Motion ◽

Correlation Coefficient ◽

Knee Arthroplasty ◽

Tibial Slope ◽

Posterior Tibial Slope ◽

Posterior Tibial ◽

Clinical Scores ◽

Total Knee ◽

The Mean

AbstractThe posterior tibial slope (PTS) is usually adjusted by less than 5 degrees, without considering its individual difference, during posterior cruciate-substituting (PS) total knee arthroplasty (TKA). The effect of these individual changes of PTS would be important because clinical results depending on postoperative PTS were reported conflictingly. We investigated the effect of the change in PTS on the postoperative range of motion (ROM) and clinical scores after PS TKA. We retrospectively reviewed 164 knees from 107 patients who underwent PS TKA with a 2-year follow-up. We analyzed the preoperative and postoperative PTS, ROM, visual analog scale pain scale, Western Ontario and McMaster University Index (WOMAC), Hospital for Special Surgery Knee Score, Knee Society Score, and Forgotten Joint Score (FJS). The association of the absolute change in PTS with ROM and clinical scores was analyzed using correlation analysis and multiple regression analysis. As a result, the mean PTS and mean ROM changed from 9.6 ± 3.4 and 120.1 ± 15.4 degrees preoperatively to 2.0 ± 1.3 and 128.4 ± 9.3 degrees postoperatively, and the mean PTS change was 7.6 ± 3.5 degrees. The PTS change had no statistically significant association with the postoperative ROM and clinical scoring systems, although it did have a weak positive correlation with WOMAC function, No 10 (difficulty in rising from sitting) (correlation coefficient = 0.342, p = 0.041), and moderate positive correlation with the FJS, No. 6 (awareness when climbing stairs) (correlation coefficient = 0.470, p = 0.001). The authors concluded that the amount of change in PTS did not affect the postoperative ROM and clinical scores, although proximal tibial resection with a constant target of PTS resulted in individually different changes in the PTS after PS TKA,

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