Low posterior tibial slope is associated with increased risk of PCL graft failure

Objectives: Meniscal injuries are extremely common. Several anatomical features of the knee, including the tibial plateau morphology, have been shown to influence knee biomechanics and the risk of ligamentous injuries. Little is known, however, how these morphological features influence the risk of isolated meniscal injuries in the ACL intact knee. In the current study, we used MRI and 3D image analysis to investigate anatomical variables of knees in patients with and without isolated meniscus tears. We hypothesized that there are differences in slopes and concavity of the tibial plateau between patients with isolated meniscus tears and matched normal controls. Methods: 65 subjects with first-instance isolated medial or lateral meniscal injuries requiring surgical fixation (Age: 15 +/- 2 years, BMI: 23.2 +/- 3.7 Kg/m2; 43% females) were matched to 65 subjects with normal knees and no prior injuries (Age: 15 +/- 2 years, BMI: 23.1 +/- 3.8 Kg/m2; 43% females) based on age, BMI and sex. Sagittal Proton Density SPACE MR images (preoperative for injured group) were used to measure the posterior slope of the medial (MTS) and lateral (LTS) tibial plateau, coronal slope of the tibial plateau (CTS), and the maximum depth of the medial tibia plateau (MTD, as a measure of medial tibial plateau concavity), following established techniques-Figure 1. Two-sample t-test was used to compare the quantified anatomical features between the cases and matched controls. Results: There were no differences in age (p = 0.999), sex distribution (p = 0.999) and BMI (p = 0.963) between the two cohorts. Compared to matched controls, patients with isolated meniscal tears had lower LTS (3.6 +/- 3.2 vs 5.6 +/- 3.0 degrees; p < 0.001), lower MTS (3.4 +/- 2.9 vs 4.9 +/- 2.5 degrees; p = 0.001) and deeper MTD (2.4 +/- 0.8 vs 1.5 +/- 0.8 mm; p < 0.001). There was no difference in CTS between the groups (3.6 +/- 1.6 vs 3.9 +/- 2.2 degrees; p = 0.300). Conclusion: This study suggests that subjects with isolated meniscus tear have a lower posterior tibial slope and a deeper MTD (more concave medial tibial plateau) than matched population who do not have a meniscus tear. This is contrary to what is known for ACL tears, where a higher posterior tibial slope and a shallower MTD have been associated with an increased risk of ACL tear. During load-bearing activities, in particular high impact movements such as jumping, increased tibial slope and decreased MTD have shown to result in greater anterior shear forces across the knee. In contrast, the less sloped and more concave plateau will experience lower shear forces but more compression, which could be detrimental to the meniscus. This study provides preliminary evidence suggesting a link between tibial plateau morphology and risk of isolated meniscal injuries. Further mechanistic studies are required to better understand the interaction between knee morphology, meniscal loading and subsequent risk of injury. [Figure: see text]

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The Effect of Posterior Tibial Slope on the Risk of Revision Surgery After Anterior Cruciate Ligament Reconstruction

The American Journal of Sports Medicine ◽

10.1177/03635465211054100 ◽

2021 ◽

pp. 036354652110541

Author(s):

Lene Dæhlin ◽

Eivind Inderhaug ◽

Torbjørn Strand ◽

Anagha P. Parkar ◽

Eirik Solheim

Keyword(s):

Anterior Cruciate Ligament ◽

Revision Surgery ◽

Graft Failure ◽

Cruciate Ligament ◽

Tibial Slope ◽

Posterior Tibial Slope ◽

Graft Size ◽

Posterior Tibial ◽

Anterior Cruciate ◽

Time From Injury

Background: A significant proportion of patients undergoing anterior cruciate ligament (ACL) reconstruction (ACLR) later experience graft failure. Some studies suggest an association between a steep posterior tibial slope (PTS) and graft failure. Purpose: To examine the PTS in a large cohort of patients about to undergo ACLR and to determine whether a steep PTS is associated with later revision surgery. Study Design: Case-control study; Level of evidence, 3. Methods: A retrospective review of a cohort undergoing isolated ACLR between 2002 and 2012 (with 8-19 years of follow-up) was conducted. Preoperative sagittal radiographs of knees in full extension were used for measurements of the PTS. There were 2 independent examiners who performed repeated measurements to assess the reliability of the method. Statistical analyses were performed to compare the PTS in the groups with and without later revision surgery. Results: A total of 728 patients, with a mean age of 28 years at the time of surgery, were included. Overall, 10% (n = 76) underwent revision surgery during the observation period. The group of injured knees had a significantly steeper PTS compared with the group of uninjured knees (9.5° vs 8.7°, respectively; P < .05). The mean PTS in the no revision group was 9.5° compared with 9.3° in the revision group (not significant). Dichotomized testing of revision rates related to PTS cutoff values of ≥10°, ≥12°, ≥14°, ≥16°, and ≥18° showed no association of PTS steepness (not significant) to graft failure. Patients with revision were younger than the ones without (mean age, 24 ± 8 vs 29 ± 10 years, respectively) and had a shorter time from injury to ACLR (mean, 14 ± 27 vs 24 ± 44 months, respectively) as well as a smaller graft size (8.2 vs 8.4 mm, respectively; P = .040). Conclusion: The current study did not find any association between a steep PTS measured on lateral knee radiographs and revision ACL surgery. However, a steeper PTS was seen in the group of injured knees compared with the group of uninjured (contralateral) knees. Independent of the PTS, younger patients, those with a shorter time from injury to surgery, and those with a smaller graft size were found to undergo revision surgery more often.

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Association Between Lateral Posterior Tibial Slope, Body Mass Index, and ACL Injury Risk

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967116688664 ◽

2017 ◽

Vol 5 (2) ◽

pp. 232596711668866 ◽

Cited By ~ 14

Author(s):

Katherine M. Bojicic ◽

Mélanie L. Beaulieu ◽

Daniel Y. Imaizumi Krieger ◽

James A. Ashton-Miller ◽

Edward M. Wojtys

Keyword(s):

Injury Risk ◽

Acl Injury ◽

Tibial Slope ◽

Posterior Tibial Slope ◽

Multivariate Logistic Regression ◽

Acl Tear ◽

Posterior Tibial ◽

Increased Risk ◽

Lateral Posterior ◽

Acl Injury Risk

Background: While body mass index (BMI), a modifiable parameter, and knee morphology, a nonmodifiable parameter, have been identified as risk factors for anterior cruciate ligament (ACL) rupture, the interaction between them remains unknown. An understanding of this interaction is important because greater compressive axial force (perhaps due to greater BMI) applied to a knee that is already at an increased risk because of its geometry, such as a steep lateral posterior tibial slope, could further increase the probability of ACL injury. Purpose: To quantify the relationship between BMI and select knee morphological parameters as potential risk factors for ACL injury. Study Design: Case-control study; Level of evidence, 3. Methods: Sagittal knee magnetic resonance imaging (MRI) files from 76 ACL-injured and 42 uninjured subjects were gathered from the University of Michigan Health System’s archive. The posterior tibial slope (PTS), middle cartilage slope (MCS), posterior meniscus height (PMH), and posterior meniscus bone angle (MBA) in the lateral compartment were measured using MRI. BMI was calculated from demographic data. The association between the knee structural factors, BMI, and ACL injury risk was explored using univariate and multivariate logistic regression. Results: PTS ( P = .043) and MCS ( P = .037) significantly predicted ACL injury risk. As PTS and MCS increased by 1°, odds of sustaining an ACL injury increased by 12% and 13%, respectively. The multivariate logistic regression analysis, which included PTS, BMI centered around the mean (cBMI), and their interaction, showed that this interaction predicted the odds of ACL rupture ( P = .050; odds ratio, 1.03). For every 1-unit increase in BMI from the average that is combined with a 1° increase in PTS, the odds of an ACL tear increased by 15%. Conclusion: An increase in BMI was associated with increased risk of ACL tear in the presence of increased lateral posterior tibial slope. Larger values of PTS or MCS were associated with an increased risk of ACL tear.

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Posterior tibial slope: the fingerprint of the tibial bone

Knee Surgery Sports Traumatology Arthroscopy ◽

10.1007/s00167-021-06578-9 ◽

2021 ◽

Author(s):

Philipp W. Winkler ◽

Brian M. Godshaw ◽

Jon Karlsson ◽

Alan M. J. Getgood ◽

Volker Musahl

Keyword(s):

Tibial Slope ◽

Posterior Tibial Slope ◽

Posterior Tibial ◽

Tibial Bone

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What is the impact of knee morphology on posterior cruciate ligament avulsion fracture in men and women: a case control study

BMC Musculoskeletal Disorders ◽

10.1186/s12891-021-03984-5 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Ning Fan ◽

Yong-chen Zheng ◽

Lei Zang ◽

Cheng-gang Yang ◽

Shuo Yuan ◽

...

Keyword(s):

Avulsion Fracture ◽

Tibial Slope ◽

Posterior Tibial Slope ◽

Control Groups ◽

Posterior Tibial ◽

Notch Width ◽

Lateral Posterior ◽

And Control ◽

Pcl Avulsion ◽

Notch Width Index

Abstract Background Several studies on the relationship between morphological parameters and traumatic diseases of the knee have already been conducted. However, few studies focused on the association between knee morphology and posterior cruciate ligament (PCL) avulsion fracture in adults. The objective of this study was to evaluate the impact of knee morphology on PCL avulsion fracture. Methods 76 patients (comprised 40 men and 36 women) with PCL avulsion fracture and 76 age- and sex-matched controls without PCL avulsion fracture were studied from 2012 to 2020. MRI measurements of the knee were acquired in the sagittal, coronal, and axial planes. The assessed measurements including intercondylar notch width index, coronal tibial slope, and medial/lateral posterior tibial slopes were compared between men and women, and between case and control groups respectively using independent sample t-tests. In addition, binary logistic regression analyses were used to identify independent risk factors of PCL avulsion fracture. Results Except notch width index (coronal) (p = 0.003) in the case groups, there was no statistical difference in the assessed measurements including notch width index (axial), coronal tibial slope, medial posterior tibial slope, and lateral posterior tibial slope between men and women in the case and control groups (p > 0.05). When female patients were analyzed, the notch width index (coronal) was significantly smaller (p = 0.0004), the medial posterior tibial slope (p = 0.018) and the lateral posterior tibial slope (p = 0.033) were significantly higher in the case group. The binary logistic regression analysis showed that the notch width index (coronal) (B = -0.347, OR = 0.707, p = 0.003) was found to be an independent factor of PCL avulsion fracture. However, none of the assessed measurements was found to have a statistical difference between the case and control groups in men (p > 0.05). Conclusions Notch width index (coronal), medial posterior tibial slope, and lateral posterior tibial slope were found to affect PCL avulsion fracture in women, but no such measurements affected the PCL avulsion fracture in men. Furthermore, a smaller notch width index (coronal) in women was found to be a risk factor in PCL avulsion fracture.

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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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Measurement of femoral posterior condylar offset and posterior tibial slope in normal knees based on 3D reconstruction

BMC Musculoskeletal Disorders ◽

10.1186/s12891-021-04367-6 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Liangxiao Bao ◽

Shengwei Rong ◽

Zhanjun Shi ◽

Jian Wang ◽

Yang Zhang

Keyword(s):

Three Dimensional ◽

Surgical Techniques ◽

Inverse Correlation ◽

Tibial Slope ◽

Posterior Tibial Slope ◽

Lateral Side ◽

Posterior Condylar Offset ◽

Posterior Tibial ◽

Significant Difference ◽

Posterior Condylar

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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