Posterior condylar offset and posterior tibial slope targets to optimize knee flexion after unicompartmental knee arthroplasty

Abstract Background Femoral posterior condylar offset (PCO) and posterior tibial slope (PTS) are important for postoperative range of motion after total knee arthroplasty (TKA). However, normative data of PCO and PTS and the correlation between them among healthy populations remain to be elucidated. The purpose of this study was to determine PCO and PTS in normal knees, and to identify the correlation between them. Methods Eighty healthy volunteers were recruited. CT scans were performed followed by three-dimensional reconstruction. PCO and PTS were measured and analyzed, as well as the correlation between them. Results PTS averaged 6.78° and 6.11°, on the medial and lateral side respectively (P = 0.002). Medial PCO was greater than lateral (29.2 vs. 23.8 mm, P < 0.001). Both medial and lateral PCO of male were larger than female. On the contrary, male medial PTS was smaller than female, while there was no significant difference of lateral PTS between genders. There was an inverse correlation between medial PCO and PTS, but not lateral. Conclusions Significant differences exhibited between medial and lateral compartments, genders, and among individuals. An inverse correlation exists between PCO and PTS in the medial compartment. These results improve our understanding of the morphology and biomechanics of normal knees, and subsequently for optimising prosthetic design and surgical techniques.

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Corrigendum to ‘An Anatomic Investigation Into the Relationship Between Posterior Condylar Offset and Posterior Tibial Slope of One Thousand One Hundred Thirty-Eight Cadaveric Knees’ [The Journal of Arthroplasty 32 (2017) 1659-1664]

The Journal of Arthroplasty ◽

10.1016/j.arth.2017.04.059 ◽

2017 ◽

Vol 32 (9) ◽

pp. 2930 ◽

Cited By ~ 1

Author(s):

Douglas S. Weinberg ◽

Jeremy J. Gebhart ◽

Glenn D. Wera

Keyword(s):

Tibial Slope ◽

Posterior Tibial Slope ◽

Posterior Condylar Offset ◽

Posterior Tibial ◽

Posterior Condylar ◽

The Relationship

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Biomechanical effect of tibial slope on the stability of medial unicompartmental knee arthroplasty in posterior cruciate ligament-deficient knees

Bone and Joint Research ◽

10.1302/2046-3758.99.bjr-2020-0128.r1 ◽

2020 ◽

Vol 9 (9) ◽

pp. 593-600 ◽

Cited By ~ 1

Author(s):

Jin-Ah Lee ◽

Yong-Gon Koh ◽

Paul Shinil Kim ◽

Ki Won Kang ◽

Yoon Hae Kwak ◽

...

Keyword(s):

Articular Cartilage ◽

Posterior Cruciate Ligament ◽

Contact Stress ◽

Knee Arthroplasty ◽

Unicompartmental Knee Arthroplasty ◽

Cruciate Ligament ◽

Tibial Slope ◽

Posterior Tibial Slope ◽

High Flexion ◽

Posterior Tibial

Aims Unicompartmental knee arthroplasty (UKA) has become a popular method of treating knee localized osteoarthritis (OA). Additionally, the posterior cruciate ligament (PCL) is essential to maintaining the physiological kinematics and functions of the knee joint. Considering these factors, the purpose of this study was to investigate the biomechanical effects on PCL-deficient knees in medial UKA. Methods Computational simulations of five subject-specific models were performed for intact and PCL-deficient UKA with tibial slopes. Anteroposterior (AP) kinematics and contact stresses of the patellofemoral (PF) joint and the articular cartilage were evaluated under the deep-knee-bend condition. Results As compared to intact UKA, there was no significant difference in AP translation in PCL-deficient UKA with a low flexion angle, but AP translation significantly increased in the PCL-deficient UKA with high flexion angles. Additionally, the increased AP translation became decreased as the posterior tibial slope increased. The contact stress in the PF joint and the articular cartilage significantly increased in the PCL-deficient UKA, as compared to the intact UKA. Additionally, the increased posterior tibial slope resulted in a significant decrease in the contact stress on PF joint but significantly increased the contact stresses on the articular cartilage. Conclusion Our results showed that the posterior stability for low flexion activities in PCL-deficient UKA remained unaffected; however, the posterior stability for high flexion activities was affected. This indicates that a functional PCL is required to ensure normal stability in UKA. Additionally, posterior stability and PF joint may reduce the overall risk of progressive OA by increasing the posterior tibial slope. However, the excessive posterior tibial slope must be avoided. Cite this article: Bone Joint Res 2020;9(9):593–600.

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Influence of posterior tibial slope on knee flexion in posterior stabilized fixed bearing primary total knee arthroplasty

International Journal of Research in Orthopaedics ◽

10.18203/issn.2455-4510.intjresorthop20201018 ◽

2020 ◽

Vol 6 (3) ◽

pp. 487

Author(s):

Sandeep Kumar Kanugula ◽

Mallesh Rathod ◽

Venugopal S. M. ◽

Mohan Babu Lebaku

Keyword(s):

Total Knee Arthroplasty ◽

Functional Outcome ◽

Knee Arthroplasty ◽

Knee Flexion ◽

Tibial Slope ◽

Posterior Tibial Slope ◽

Posterior Tibial ◽

Group A ◽

Total Knee ◽

Pcl Substituting

Background: The goal of total knee arthroplasty (TKA) is to relieve pain and maintain stable range of motion (ROM) for day to day activities. Among the various factors, posterior tibial slope slope (PTS) may play an important role in achieving good postoperative knee flexion. Our study aims to know the effectiveness of PTS on the ROM of the knee in a posterior cruciate ligament (PCL)-substituting TKA.Methods: A total of 125 unilateral PCL-substituting TKA’s were included in the study. Based on postoperative PTA which was measured on lateral radiograph, patients were divided into 3 groups, Group A (PTS of ≤2) comprise of 24 patients. Group B consists of 91 patients (PTS of 3 to 7). Group C includes 10 patients (PTS of 8 or more). Functional outcome was measured by using knee society score (KSS) and Western Ontario and McMaster Universities osteoarthritis index (WOMAC) which were evaluated preoperatively and at 18months post operatively.Results: Mean postop ROM was 92.91 ± 10.632; 107.24±10.905; 107.49±13.944 in group A, B, C respectively which was significantly related to mean postop PTS (0.74; 5.62; 9.87 in group A, B, C respectively) (P<0.05). Functional outcome was measured by KSS and WOMAC which showed no significant difference pre and postoperatively.Conclusions: The results of our study validate the hypothesis that a positive correlation exists between the postoperative flexion and PTS in the PCL-substituting TKA, an increase in PTS can lead to a greater degree of the knee flexion for every extra degree of PTS.

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The Medial Tibial Plateau Can Be Used as a Direct Anatomical Reference for the Posterior Tibial Slope in Medial Unicompartmental Knee Arthroplasty

The Journal of Knee Surgery ◽

10.1055/s-0041-1740384 ◽

2021 ◽

Author(s):

Shigeshi Mori ◽

Masao Akagi ◽

Akihiro Moritake ◽

Ichiro Tsukamoto ◽

Kotaro Yamagishi ◽

...

Keyword(s):

Knee Arthroplasty ◽

Unicompartmental Knee Arthroplasty ◽

Tibial Plateau ◽

Tibial Slope ◽

Posterior Tibial Slope ◽

Posterior Tibial ◽

Medial Unicompartmental Knee Arthroplasty ◽

The Mean ◽

Ct Data ◽

The Individual

AbstractThere has been no consensus about how to determine the individual posterior tibial slope (PTS) intraoperatively. The purpose of this study was to investigate whether the tibial plateau could be used as a reference for reproducing individual PTS during medial unicompartmental knee arthroplasty (UKA). Preoperative computed tomography (CT) data from 48 lower limbs for medial UKA were imported into a three-dimensional planning software. Digitally reconstructed radiographs were created from the CT data as the lateral knee plain radiographs and the radiographic PTS angle was measured. Then, the PTS angles on the medial one-quarter and the center of the MTP (¼ and ½ MTP, respectively), and that on the medial tibial eminence (TE) were measured on the sagittal multiplanar reconstruction image. Finally, 20 lateral knee radiographs with an arthroscopic probe placed on the ¼ and the ½ MTP were obtained intraoperatively, and the angle between the axis of the probe and the tangent line of the plateau was measured. The mean radiographic PTS angle was 7.9 ± 3.0 degrees (range: 1.7–13.6 degrees). The mean PTS angles on the ¼ MTP, the ½ MTP, and the TE were 8.1 ± 3.0 degrees (1.2–13.4 degrees), 9.1 ± 3.0 degrees (1.4–14.7 degrees), and 9.9 ± 3.1 degrees (3.1–15.7 degrees), respectively. The PTS angles on the ¼ MTP and the ½ MTP were strongly correlated with the radiographic PTS angle (r =0.87 and 0.80, respectively, p < 0.001). A statistically significant difference was observed between the mean angle of the radiographic PTS and the PTS on the TE (p < 0.01). The mean angle between the axis of the probe and the tangent line of the tibial plateau was −0.4 ± 0.9 degrees (−2.3–1.3 degrees) on the ¼ MTP and −0.1 ± 0.7 degrees (−1.5–1.2 degrees) on the ½ MTP, respectively. An area from the medial one-quarter to the center of the MTP could be used as an anatomical reference for the individual PTS.

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