Signification of the unusual delineation of the anterior meniscofemoral ligament of Humphrey during knee arthro-CT

MRI study of the cruciate ligaments and menisco-femoral ligaments of the knee

PURPOSE

It has been argued that the meniscus-femoral ligaments disappear with age. We therefore analyzed the presence of the meniscus-femoral ligaments, in MRI.

MATERIALS AND METHODS

We measured the PCL, ACL and MFL, noting their presence or absence in 120 Knee MRIs, 51 in women and 69 in men. All knees underwent MRI in the coronal, sagittal and axial planes. T1 and T2 weighted sequences were obtained. A descriptive statistical study of all the variables was carried out, and a comparative study was performed between sexes, sides and age groups.

RESULTS

The MFLp was more frequent, found in 67 (55.8%) cases, than the MFLa, in 36 (30%) cases, and both together were present in 27 (22.5%) knees. We found a strong correlation between ACL length and PCL length (p = 0.001), we found no correlation between the presence of the posterior MFL either with age (p = 0.307) or with sex (p = 0.779) or side (p = 0.733). We also found no relationship between the presence of the anterior MFL and age (p = 0.553), or sex (p = 0.913), or laterality (p = 0.082).

CONCLUSION

We found a strong correlation between ACL length and PCL length. In our study, the presence of the posterior MFL was more frequent, being present in 55.68%, while the anterior MFL was found in 30% of the knees. We did not observe that the presence of LMF decreases with age.

Relationship of the Cruciate and Meniscofemoral Ligaments with the Knee Osteology. An Anatomical Study

Objective  To analyze the dimensions of the posterior cruciate ligament (PCL), anterior cruciate ligament (ACL), the presence of meniscus-femoral ligaments MFLs in human knees, and the correlation with the dimensions of the knee skeleton. Methods  Anatomical study on 29 specimens of human knees in which we measured the length and width of the cruciate and meniscus-femoral ligaments and the dimensions of femoral and tibia condyles and the femoral notch. The ACL length was calculated with different degrees of knee flexion. The relationship between the ligaments and bone dimensions were analyzed. Results  The length of the ACL and the PCL were similar. Posterior MFL was more frequent and longer than the anterior MFL. We found the posterior MFL in the 72.41% of the knees and anterior MFL in 20.69%. The ACL presented 30% of its maximum length up to 60°, approximately half of its length between 90° and 120°, reaching its maximum length at 170°. We found a strong correlation between the length of the ACL and that of the PCL ( p  = 0.001). However, the lengths of the ACL and PCL were not related with the bone dimensions. Conclusion  We have found no correlations between the cruciate and MFLs and the anatomical dimensions of the intercondylar notch and the proximal tibia and distal femur. The presence of the posterior MFL was more frequent and longer than that of the anterior ligament.

Clinical Anatomy of the Anterior Meniscofemoral Ligament of Humphrey: An Original MRI Study, Meta-analysis, and Systematic Review

Background:

The anterior meniscofemoral ligament (aMFL) of Humphrey is an anatomically variable fibrous band of connective tissue that attaches between the lateral aspect of the medial femoral condyle and posterior horn of the lateral meniscus, running posterior to the anterior cruciate ligament and anterior to the posterior cruciate ligament (PCL). The presence of an intact aMFL may contribute to stabilization of the lateral compartment of the knee joint.

Purpose:

The original magnetic resonance imaging (MRI) arm of this study aimed to assess the aMFL incidence among Polish patients. The goal of the systematic review and meta-analysis was to review the literature discussing the clinical anatomy of the aMFL and provide data on its prevalence. It was hypothesized that significant heterogeneity exists within the published literature.

Study Design:

Cross-sectional study and systematic review; Level of evidence, 3.

Methods:

A retrospective investigation was performed on the MRI scans of 100 knees (52 right, 48 left) of Polish patients. Scans were randomly selected from a database of MRI examinations performed in 2019. For the meta-analysis, major online databases were queried for data on the aMFL, and 2 authors independently assessed and extracted data from all included studies. A quality assessment of the included articles was performed using the Anatomical Quality Assessment tool.

Results:

In the MRI arm of this study, the aMFL was found in 62 of the 100 lower limbs. The meta-analysis included 41 studies with a total of 4220 limbs. The aMFL was present in 55.5% (95% CI, 45.5%-65.3%) of cases. Arthroscopic studies yielded the highest prevalence (82.3% [95% CI, 36.6%-100.0%]); of MRI studies, the highest prevalence was at 3.0-T strength (51.0% [95% CI, 13.3%-88.2%]).

Conclusion:

Significant variability in the prevalence of the aMFL was found in the literature. More emphasis should be placed on the clinical relevance of injuries to the aMFL because of its significant role in the function of the knee. It is important to be aware that, because of the anatomy of the aMFL, the ligament can also function to support a torn PCL.

Anterior and posterior meniscofemoral ligaments: MRI evaluation

Although meniscofemoral ligaments are distinct anatomic units, their anatomy and function are controversial from an anatomic and radiologic point of view. Five hundred knee MR examinations were retrospectively studied in an effort to demonstrate the incidence and variations regarding sex and age distribution, as well as the anatomy of the meniscofemoral ligament at magnetic resonance imaging. Patients were mostly men, three hundred and twelve, in contrast with women who were fewer, one hundred eighty-eight patients. The mean age of the patients who were included in this study was 46 years. More than half of them were between 20 and 40 years old; one hundred thirty-three patients among 20 to 30 years old and one hundred and one patients among 31 and 40 years old, in total two hundred thirty-four patients.

Contribution of the meniscofemoral ligament as a restraint to the posterior tibial translation in a porcine knee

The meniscofemoral ligament (MFL) is a major structure in the posterior aspect of the porcine knee together with the posterior cruciate ligament (PCL). While the porcine knee is a frequently used animal model for biomechanical evaluation of PCL reconstruction techniques, the contribution of the MFL to stability of the porcine knee is not well understood. The purpose of this study is (1) to evaluate the kinematics of the knee after sequential cutting of the PCL and MFL and (2) to determine the in situ forces of the PCL and MFL in response to a posterior tibial load of 89 N using the robotic/universal force-moment sensor system from 15 degrees to 90 degrees of knee flexion. Ten porcine knees were used in this study. The magnitude of posterior tibial translation under a posterior tibial load was significantly increased (P < 0.01) after sequential transection of the PCL and the MFL at each testing angle compared to the intact condition. The in situ force of the PCL was highest at 60 degrees of flexion (82.3 +/- 8.6 N) and lowest at 15 degrees of flexion (45.1 +/- 15.9 N). The in situ force of the MFL was highest at 15 degrees of flexion (24.3 +/- 6.5 N) and lowest at 90 degrees of flexion (12.9 +/- 10.5 N). The findings in this study revealed a biomechanical contribution of the MFL as the secondary restraint to the posterior tibial translation in conjunction with the PCL especially near full extension.