Anatomical variations of knee ligaments in magnetic resonance imaging: pictorial essay (original) (raw)
Correlation of Magnetic Resonance Imaging With Knee Anterolateral Ligament Anatomy
Orthopaedic Journal of Sports Medicine, 2015
Background: Anatomic and magnetic resonance imaging (MRI) studies have recently characterized the knee anterolateral ligament (ALL). So far, no study has focused on confirming whether the evaluated MRI parameters truly correspond with ALL anatomy. Purpose: To assess the validity of MRI in detecting the ALL using an anatomic evaluation as reference. Study Design: Descriptive laboratory study. Methods: A total of 13 cadaveric knees were subjected to MRI and then to anatomic dissection. Dissection was performed according to previous anatomic study methodology. MRIs were performed with a 0.6-to 1.5-mm slice thickness and prior saline injection. The following variables were analyzed: distance from the origin of the ALL to the origin of the lateral collateral ligament (LCL), distance from the origin of the ALL to its bifurcation point, maximum length of the ALL, distance from the tibial insertion of the ALL to the articular surface of the tibia, ALL thickness, and ALL width. The 2 sets of measurements were analyzed using the Spearman correlation coefficient (r) and Bland-Altman plots. Results: The ALL was clearly observed in all dissected knees and MRI scans. It originated anterior and distal to the LCL, close to the lateral epycondile center, and showed an anteroinferior path toward the tibia, inserting between the Gerdy tubercle and the fibular head, around 5 mm under the lateral plateau. The r values tended to increase together for all studied variables between the 2 methods, and all were statistically significant, except for thickness (P ¼ .077). Bland-Altman plots showed a tendency toward a reduction of ALL thickness and width by MRI compared with anatomic dissection. Conclusion: MRI scanning as described can accurately assess the ALL and demonstrates characteristics similar to those seen under anatomic dissection. Clinical Relevance: MRI can accurately characterize the ALL in the anterolateral region of the knee, despite the presence of structures that might overlap and thus cause confusion when making assessments based on imaging methods.
Canadian Association of Radiologists journal, 2016
Purpose: The anatomy of the lateral knee compartment has been recently further explored with description of the anterolateral knee ligament (ALL). The purpose of this study was to confirm the presence of ALL on cadaveric knees and to describe its normal anatomy in young healthy volunteers, utilizing a high-resolution 3-dimensional (3D) pulse sequence. Methods: Dissection was performed on 9 cadaveric knees in order to confirm the presence of ALL. Conventional 2-dimensional sequences of 10 knees at 1.5 T and 10 knees at 3 T, with a slice thickness of 2-4 mm, were reviewed for the presence of ALL. A 3D T2/T1-weighted gradient echo sequence (constructive interference in steady state [CISS]), yielding in-plane resolution of 0.4 mm  0.4 mm  0.4 mm, was applied in 14 healthy volunteers (26 knees). All 3D images were manipulated using multiplanar reconstruction (MPR) and the presence and width of ALL were recorded. Results: Cadaveric dissection disclosed the presence of ALL in 8 of 9 knees. Conventional knee MR imaging depicted ALL only on coronal images (18 of 20) whereas the CISS revealed ALL on 24 of 26 studied knees (92.3%). ALL has a mean thickness of 1.1 AE 0.27 mm measured on coronal MR images. Conclusions: ALL can be thoroughly assessed in young healthy individuals with the use of high-resolution 3D MR imaging with MPR at 1.5 T.
Assessment of the Anterolateral Ligament of the Knee by Magnetic Resonance Imaging
Joints
Purpose The purpose of this study was to describe the anatomy of the anterolateral ligament (ALL) of the knee by the use of 1.5 Tesla (T) magnetic resonance imaging (MRI) in a series of young patients without knee injuries. Methods Subjects aged 18 or older without an anterior cruciate ligament injury, as confirmed on MRI, were included. MRI examinations were all performed on 1.5 T scans. The ALL was defined as the low signal band originating from the region of the lateral epicondyle of the femur, crossing the proximal surface of the lateral collateral ligament, deep to the iliotibial band, and inserting onto the tibia between the Gerdy's tubercle and the fibular head. Results Twenty-six patients met the eligibility criteria and were enrolled into the study. In one patient, it was not possible to visualize the ALL. In all the other subjects, the ligament originated anterior and distal to the lateral epicondyle and inserted on the proximal tibia approximately 5 mm below the joint...
MRI features of the anterolateral ligament of the knee
Skeletal Radiology, 2014
Objective Evaluate the visibility and describe the anatomical features of the anterolateral ligament of the knee using MRI. Materials and methods Magnetic resonance imaging examinations of the knee were independently reviewed by two musculoskeletal radiologists and assessed for the visibility of the anterolateral ligament under direct cross-referencing of axial and coronal images as complete, partial, or non-visible. Distal insertion site (tibial, meniscal), distance to lateral tibial plateau, measurements (length, width, thickness), and associated imaging findings were also tabulated. Clinical and surgical records were also reviewed. Results Seventy MRI scans from 60 consecutive subjects were included in the study. Mean age was 40 years, body mass 74.9 kg, and height 1.72 m. The subject population was 53 % male, most of the knees were from the left side (51 %), and chronic pain was the main clinical symptom (40 %). Nine knees (13 %) had undergone previous surgery. The anterolateral ligament was identified in 51 % of the knees: completely visible in 11 % and partially visible in 40 %. In all visible cases, the distal insertion site was identified on the tibia, with a mean distance of 5.7 mm to the plateau. A completely visible ligament had a mean length of 33.2 mm, thickness of 5.6 mm, and width of 1.9 mm. Inter-observer agreement for ligament presence was significant (κ=0.7). Statistical analyses showed a trend to be more visible in men, with a longer length compared with women. Conclusions Magnetic resonance imaging clearly identifies the anterolateral ligament of the knee in slightly more than half of cases, being partially visible in most of them. In all cases, a tibial insertion is characterized.
Erratum to: MRI features of the anterolateral ligament of the knee
Skeletal Radiology, 2014
Objective Evaluate the visibility and describe the anatomical features of the anterolateral ligament of the knee using MRI. Materials and methods Magnetic resonance imaging examinations of the knee were independently reviewed by two musculoskeletal radiologists and assessed for the visibility of the anterolateral ligament under direct cross-referencing of axial and coronal images as complete, partial, or non-visible. Distal insertion site (tibial, meniscal), distance to lateral tibial plateau, measurements (length, width, thickness), and associated imaging findings were also tabulated. Clinical and surgical records were also reviewed. Results Seventy MRI scans from 60 consecutive subjects were included in the study. Mean age was 40 years, body mass 74.9 kg, and height 1.72 m. The subject population was 53 % male, most of the knees were from the left side (51 %), and chronic pain was the main clinical symptom (40 %). Nine knees (13 %) had undergone previous surgery. The anterolateral ligament was identified in 51 % of the knees: completely visible in 11 % and partially visible in 40 %. In all visible cases, the distal insertion site was identified on the tibia, with a mean distance of 5.7 mm to the plateau. A completely visible ligament had a mean length of 33.2 mm, thickness of 5.6 mm, and width of 1.9 mm. Inter-observer agreement for ligament presence was significant (κ=0.7). Statistical analyses showed a trend to be more visible in men, with a longer length compared with women. Conclusions Magnetic resonance imaging clearly identifies the anterolateral ligament of the knee in slightly more than half of cases, being partially visible in most of them. In all cases, a tibial insertion is characterized.
Assessment of the anterolateral ligament of the knee by 1.5 T magnetic resonance imaging
The Journal of international medical research, 2018
Objective This study was performed to evaluate the visibility of the knee's anterolateral ligament (ALL) by magnetic resonance (MR) imaging when evaluating injuries of the ALL in relation to injuries of the anterior cruciate ligament (ACL). Methods Two reviewers retrospectively analyzed MR images for the visibility and dimensions of the ALL and the relationship between ALL and ACL injuries. The intraclass correlation coefficient (ICC) and kappa analysis were used to assess interobserver reliability. The chi-square test was used to assess the relationship between ALL and ACL injuries. Results The entire ALL was viewed on 82% of all MR images. The ICC for ALL visualization ranged from moderate to perfect between the two readers. There was almost perfect agreement between the reviewers when evaluating ALL dimensions. The mean length ± standard error, median thickness, and mean width ± standard error of the ALL were 36.5 ± 0.6 mm, 2.5 mm, and 8.2 ± 0.2 mm, respectively. A statistica...
Radiographic Identification of the Primary Medial Knee Structures
The Journal of Bone and Joint Surgery (American), 2009
Background: Radiographic landmarks for medial knee attachment sites during anatomic repairs or reconstructions are unknown. If identified, they could assist in the preoperative evaluation of structure location and allow for postoperative assessment of reconstruction tunnel placement.
Magnetic resonance imaging of variants of the knee
Singapore medical journal, 2008
Magnetic resonance imaging has become the imaging modality of choice for evaluation of internal derangements of the knee. Anatomical variants are often an incidental finding on these examinations. Knowledge and recognition of variants is important, not only to avoid misdiagnosis but also to avoid additional imaging and over-treatment. This pictorial essay provides an overview of variants encountered during a review of 1,873 magnetic resonance imaging examinations of the knee. Emphasis is laid on these variants that are clinically important.
MRI evaluation of the anterolateral ligament of the knee: assessment in routine 1.5-T scans
Objective This study evaluated the ability of routine 1.5-T MRI scans to visualize the anterolateral ligament (ALL) and describe its path and anatomic relations with lateral knee structures. Materials and methods Thirty-nine 1.5-T MRI scans of the knee were evaluated. The scans included an MRI knee protocol with T1-weighted sequences, T2-weighted sequences with fat saturation, and proton density (PD)-weighted fast spinecho sequences. Two radiologists separately reviewed all MRI scans to evaluate interobserver reliability. The ALL was divided into three portions for analyses: femoral, meniscal, and tibial. The path of the ALL was evaluated with regard to known structural parameters previously studied in this region. Results At least a portion of the ALL was visualized in 38 (97.8 %) cases. The meniscal portion was most visualized (94.8 %), followed by the femoral (89.7 %) and the tibial (79.4 %) portions. The three portions of the ALL were visualized in 28 (71.7 %) patients. The ALL was characterized with greater clarity on the coronal plane and was visualized as a thin, linear structure. The T1-weighted sequences showed a statistically inferior ligament visibility frequency.With regard to the T2 and PD evaluations, although the visualization frequency in PD was higher for the three portions of the ligament, only the femoral portion showed significant values. Conclusion The ALL can be visualized in routine 1.5-TMRI scans. Although some of the ligament could be depicted in nearly all of the scans (97.4 %), it could only be observed in its entirety in about 71.7 % of the tests.
Anatomy and magnetic resonance imaging of the posterolateral structures of the knee
Clinical Anatomy, 1997
The purpose of the present study was to provide detailed information of the morphological and radiological characteristics of the posterolateral structures of the knee. Muscles and ligaments of the posterolateral part of the knee were studied by dissections of 50 adult cadaver knees and by Magnetic Resonance Imaging (MRI) before and after dissections for comparisons. Diverse morphological characteristics of the arcuate ligament were found. The fabellofibular ligament was present in 42.1% of the knees dissected, whereas the popliteofibular ligament was found in 37.5%. A ligamentous structure, which could be called the posterior tibial ligament, was found in 31.6% of the cases that originated from the lateral part of the capsule proximally and inserted distally on the mid portion of the proximal tibia. By comparing the cross sections and the dissections of the cadaver knees, the popliteus muscle, the arcuate ligament, the fibular collateral ligament, the popliteofibular ligament, and the fabellofibular ligament could be identified in MRI. Comprehensive understanding of the posterolateral anatomy of the knee and improved identification of the structures in MRI will help clinicians to make a more accurate and noninvasive diagnosis of posterolateral instability.
The Anatomy of the Medial Part of the Knee
2000
Background: While the anatomy of the medial part of the knee has been described qualitatively, quantitative descriptions of the attachment sites of the main medial knee structures have not been reported. The purpose of the present study was to verify the qualitative anatomy of medial knee structures and to perform a quantitative evaluation of their anatomic attachment sites as well as their relationships to pertinent osseous landmarks.
Magnetic Resonance Imaging Abnormalities in Symptomatic and Contralateral Knees
The American Journal of Sports Medicine, 2006
BackgroundAfter trauma, internal knee lesions are found in approximately two thirds of patients. However, magnetic resonance imaging abnormalities have also been described in asymptomatic volunteers.HypothesisNot all visualized lesions in symptomatic posttraumatic knees are the result of recent trauma; there are subgroups of lesions that may be preexistent.Study DesignCross-sectional study (prevalence); Level of evidence, 2.MethodsPatients visiting their general practitioners after knee trauma were invited for magnetic resonance imaging of both knees. Prevalence of knee abnormalities was compared between symptomatic and asymptomatic knees. Multivariable analysis was performed to investigate the association between lesions that were seen in symptomatic and asymptomatic knees (ie, effusion and meniscal tears) and recent trauma, history of old trauma, age, and osteoarthritis.ResultsIn 134 participants, ligament lesions were found almost exclusively in symptomatic knees. Meniscal lesion...
Knee Surgery, Sports Traumatology, Arthroscopy, 2015
A palpable macroscopic thickening of the lateral capsule was identified in 4/10 specimens. MRI analysis revealed a 2-4 mm thickening of the central third of the lateral capsule in 3/10 specimens. On histological analysis, the lateral capsular thickening demonstrated properties similar to both capsule and ligament. Conclusions In fresh-frozen cadaveric specimens, macroscopic and MRI evaluation of the lateral capsule of the knee revealed variations in morphology without consistent capsuloligamentous anatomy and specifically no discrete lateral capsular ligament. Further investigation in the form of clinical and mechanical relevance of the lateral capsular structures is of paramount importance before limited anatomical data can be utilized to drive clinical decision-making and patient care.
Diagnostics
The purpose of this study was to compare the measurement of several anatomical features of the medial patellofemoral ligament (MPFL) between magnetic resonance imaging (MRI) and by direct fashion during dissection. We hypothesized that the measurements between these two techniques would agree. MRI of 30 fresh-frozen cadaveric knees was followed by dissection. MPFL patella and femoral attachment were evaluated; their shape, length, and width were measured; and measurements were compared. MRI was deemed unreliable for the determination of several of the aforementioned anatomical features. Important findings include: (a) observations on MPFL attachment at medial patella side and attachment to quadriceps were identical between dissection and MRI; (b) average width at patella insertion was significantly different between the two methods (p = 0.002); and (c) an attachment to the quadriceps tendon was present in 20/30 specimens and d. detailed measurements of a thin, non-linear, and three-...
The anterior knee: normal variants, common pathologies, and diagnostic pitfalls on MRI
Skeletal radiology, 2018
The anterior aspect of the knee is host to an array of normal variants and potential pathology. These normal anatomic variants are often encountered and may mimic pathologies, leading to unnecessary work-up and treatments. On the other hand, there are several subtle abnormalities that may be easily overlooked or mistaken for variants or other injuries or diseases. Recognition of these diagnostic challenges is essential for radiologists to make an accurate diagnosis. This article reviews normal anatomical variants of ligaments, tendons, bones, and other important structures of the anterior knee, focusing on magnetic resonance imaging features. Commonly encountered injuries and abnormalities of the anterior knee and their diagnostic pitfalls are also discussed, highlighting findings on magnetic resonance imaging.