Narrow Notch Width and Low Anterior Cruciate Ligament Volume Are Risk Factors for Anterior Cruciate Ligament Injury: A Magnetic Resonance Imaging-Based Study

Background: The relationship between anterior cruciate ligament (ACL) injury and anatomical structures is still a topic of debate. Purpose: The aim of this study was to compare knee geometry in demographically matched ACL-injured and ACL-intact athletes. Methods: We conducted a case-control study comparing 2 groups, each consisting of 55 professional athletes (44 men and 11 women): 1 group with complete ACL tears (cases) and 1 group with intact ACLs (controls). The groups were compared using magnetic resonance imaging (MRI) in terms of intercondylar notch geometry, tibial plateau characteristics, and ACL volume. Results: Among cases and controls, we found the cases had lower notch width (20.24 ± 2.68 mm vs. 22.04 ± 2.56 mm, respectively) and notch width index (0.29 ± 0.03 vs. 0.31 ± 0.03, respectively). The mean ACL volume in the cases (1181.63 mm3 ± 326 mm3) was also lower than in controls (1352.61 mm3 ± 279.84 mm3). The parameters of tibial slope geometry were comparable between groups. In addition, women had lower ACL volume than men (1254 ± 310 mm3 vs. 890 ± 267 mm3, respectively) and higher medial posterior tibial slope (4.76 ± 2.6 vs. 6.63 ± 1.83, respectively). Among cases, women had narrower notch width than men (16.9 ± 2.42 mm vs. 21.08 ± 2.03 mm). However, notch width index was comparable between male (0.3 ± 0.02) and female (0.28 ± 0.03) cases. Conclusion: Our findings suggest that narrow notch width and low ACL volume may enhance the risk of ACL injury among athletes. There was no association found between posterior tibial slope and ACL injury between athletes with injured ACLs and controls. Further study is indicated.

Stenotic intercondylar notch is not a risk factor for posterior cruciate ligament rupture: a morphological analyses using magnetic resonance imaging

Purpose The present study aimed to examine the factors related to the morphological characteristics of the femoral condyle in posterior cruciate ligament rupture in female and male populations. Methods One hundred and three patients (41 females, 62 males) with posterior cruciate ligament rupture from 2010 to 2020 were included in this retrospective case–control study. The sex and age of the posterior cruciate ligament rupture group were matched to those of the control group (41 females, 62 males; age range 16–69 years). Magnetic resonance imaging was used to measure the intercondylar notch width, femoral condylar width, and intercondylar notch angle in both the axial and coronal images. The ‘α’ angle was also measured using magnetic resonance imaging. The notch width index is the ratio of the intercondylar notch width to the femoral condylar width. Three types of intercondylar notch shapes (types A, U, and W) were evaluated in the axial magnetic resonance imaging images. Results The difference in the mean coronal notch width index between the study groups was statistically significant in the female population. The difference in the mean coronal femoral condylar width between the study groups was statistically significant in the male population. Conclusions A larger coronal notch width index was the greatest risk factor for posterior cruciate ligament rupture in the female population. In the male population, decreased coronal condylar width was the greatest risk factor for posterior cruciate ligament rupture. The results did not indicate that patients with a PCL rupture have a stenotic intercondylar notch. Posterior cruciate ligament injury prevention strategies could be applied to females with a larger coronal notch width index and males with a decreased condylar width. Levels of evidence Level III.

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

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.

Is There a Role of Meniscal Morphology in the Risk of Noncontact Anterior Cruciate Ligament Rupture? A Case–Control Study

The purpose of this study was to identify the anatomical risk factors and determine the role of meniscal morphology in noncontact anterior cruciate ligament (ACL) rupture. A total of 126 patients (63 with noncontact ACL rupture and 63 age- and sex-matched controls) with intact menisci were included in this retrospective case–control study. On knee magnetic resonance imaging (MRI), meniscal morphometry (anterior, corpus, and posterior heights and widths of each meniscus), tibial slope (medial and lateral separately), notch width index, roof inclination angle, anteromedial bony ridge, tibial eminence area, and Q-angle measurements were assessed. The data were analyzed using multiple regression analyses to identify independent risk factors associated with ACL rupture. Using a univariate analysis, medial and lateral menisci anterior horn heights (p < 0.001; p < 0.003), medial and lateral menisci posterior horn heights (p < 0.001; p < 0.001), lateral meniscus corpus width (p < 0.004), and notch width index (p < 0.001) were significantly higher in the control group. Lateral tibial slope (p < 0.001) and anteromedial bony ridge thickness (p < 0.001) were significantly higher in the ACL rupture group. Multivariate analysis revealed that decreased medial meniscus posterior horn height (odds ratio [OR]: 0.242; p < 0.001), increased lateral meniscus corpus width (OR: 2.118; p < 0.002), increased lateral tibial slope (OR: 1.95; p < 0.001), and decreased notch width index (OR: 0.071; p = 0.046) were independent risk factors for ACL rupture. Notch stenosis, increased lateral tibial slope, decreased medial meniscus posterior horn height, and increased lateral meniscus corpus width are independent anatomical risk factors for ACL rupture. Meniscal morphological variations also play a role in ACL injury. Level of Evidence Level III, retrospective case–control study.

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

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 and determine risk factors in men and women separately. Methods A retrospective case-control study of 48 patients (comprised 25 men and 23 women) with PCL avulsion fracture compared with 48 age- and sex-matched controls was performed from 2012 to 2018. MRI measurements of the knee were acquired in the sagittal, coronal, and axial sequences. The assessed measurements including intercondylar notch width index, medial/lateral posterior tibial slopes, and coronal tibial slope were compared between case and control groups in both women and men. Univariable and binary logistic regression analyses were used to identify independent risk factors that were associated with PCL avulsion fracture. Results When female patients were analyzed, the notch width index (coronal) was significantly smaller, and the lateral posterior tibial slope was significantly higher in the case group. The binary logistic regression analysis showed that the notch width index (coronal) (B = -0.307, OR = 0.735, p = 0.025) was found to be an independent factor. When male patients were analyzed, no radiographic parameter was found to have a statistical difference between the case and control groups. Conclusions Notch width index (coronal) 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.

The Effect of the Intercondylar Notch Shape and Notch Width Index on Anterior Cruciate Ligament Injuries

Background: Anterior cruciate ligament is one of the commonly injured ligaments in knee. The shape and dimension of the femoral notch has been linked with the risk of anterior cruciate ligament injury. The aim of this study was to study the risk of Anterior cruciate ligament injury with notch morphology in the Nepalese population.Methods: This study is a case control study. Cases undergoing arthroscopic surgery at 2 tertiary level centers were enrolled. Patients with arthroscopic confirmation of Anterior cruciate ligament tear were taken as case and those without tear were taken as control. Axial Magnetic resonance Imaging sequence was used to study notch. Sections at the level of popliteal groove was taken for study and shapes were identified as A, U and W type, and notch width index was calculated. These variables were correlated with presence or absence of Anterior cruciate ligament tear.Results: Out of 118 cases, 59 had tear, and 59 had no tear. Tear was found in 74% of Type A notch compared to 30.15% in Type U notch. The femoral notch width index was low in 42.59% of A type notch patients compared to 20.63% with U type notch. Analysis of notch width index among patients with Anterior cruciate ligament tears, showed that 40.67% of Anterior cruciate ligament torn knee had narrow notch compared to 22% in non- injured group, which was statistically significant.Conclusions: Type A notch and narrow notch both are risk factors for Anterior cruciate ligament tear.Keywords: Anterior cruciate ligament; injury; notch.

ACL Size and Notch Width Between ACLR and Healthy Individuals: A Pilot Study

Background: Given the relatively high risk of contralateral anterior cruciate ligament (ACL) injury in patients with ACL reconstruction (ACLR), there is a need to understand intrinsic risk factors that may contribute to contralateral injury. Hypothesis: The ACLR group would have smaller ACL volume and a narrower femoral notch width than healthy individuals after accounting for relevant anthropometrics. Study Design: Cross-sectional study. Level of Evidence: Level 3. Methods: Magnetic resonance imaging data of the left knee were obtained from uninjured (N = 11) and unilateral ACL-reconstructed (N = 10) active, female, collegiate-level recreational athletes. ACL volume was obtained from T2-weighted images. Femoral notch width and notch width index were measured from T1-weighted images. Independent-samples t tests examined differences in all measures between healthy and ACLR participants. Results: The ACLR group had a smaller notch width index (0.22 ± 0.02 vs 0.25 ± 0.01; P = 0.004; effect size, 1.41) and ACL volume (25.6 ± 4.0 vs 32.6 ± 8.2 mm3/(kg·m)−1; P = 0.025; effect size, 1.08) after normalizing by body size. Conclusion: Only after normalizing for relevant anthropometrics, the contralateral ACLR limb had smaller ACL size and narrower relative femoral notch size than healthy individuals. These findings suggest that risk factor studies of ACL size and femoral notch size should account for relevant body size when determining their association with contralateral ACL injury. Clinical Relevance: The present study shows that the method of the identified intrinsic risk factors for contralateral ACL injury could be used in future clinical screening settings.