Evaluation of ulnar variance on wrist MR imaging: is it a reliable measure?

OBJECTIVE: To determine if ulnar variance can be evaluated by magnetic resonance (MR) imaging and if this measure can be used as a reliable indicator when correlated to the gold standard technique, conventional radiography (CR). MATERIALS AND METHODS: From January to July 2018, the MR images of 64 participants, comprising 66 wrists (mean age 34.9 years; 33 females; 31 males), were obtained. Among those, 29 were referred for evaluation of the wrist for different medical reasons and 35 were asymptomatic volunteers from our radiology group. All subjects had a plain radiography of the wrist in a posteroanterior view with a mean interval between images of 1 day. Local ethics committee approved the study and written informed consent was obtained from all patients. Two musculoskeletal radiologists evaluated the images. Correlation coefficients and a linear regression model were used for statistical analyses. RESULTS: Intra- and inter-observer analyses were performed for both diagnostic methods with results showing concordance (intra-observer: kappa score: MR 0.915/CR 0.931; p < 0.05; inter-observer: kappa score: MR 0.857/CR 0.931; p < 0.05). The intraclass correlations of MR and CR to evaluate agreement between the radiologists was slightly higher for radiologist #1 (0.771) than for radiologist #2 (0.659). A linear regression model showed good model fit indicating that MR does correlate with the ulnar variance as measured by CR (CR = 0.554 + 0.897 × MR, R2 = 0.665). CONCLUSION: Although CR is the gold standard method for the evaluation of ulnar variance, our study demonstrated that MR can be used as a reliable qualitative option.

Assessment of the Anterolateral Ligament of the Knee by Magnetic Resonance Imaging in Acute Injuries of the Anterior Cruciate Ligament.

PURPOSE: To evaluate the epidemiology of injuries and abnormalities of the anterolateral ligament (ALL) by magnetic resonance imaging (MRI) in cases of acute anterior cruciate ligament (ACL) injury. METHODS: MRIs of patients with acute ACL injury were evaluated. Acute injuries of the ACL were considered in cases in which the patient reported knee trauma occurring less than 3 weeks prior and when bone bruise in the femoral condyles and tibial plateau was identified. ALL abnormality was considered when it showed proximal or distal bone detachment, discontinuity of fibers, or irregular contour associated with periligamentous edema. The ALL was divided into femoral, tibial, and meniscal portions, and the lesions and/or abnormalities of each portion were characterized. The correlation of ALL injury with injuries of the lateral meniscus was evaluated. RESULTS: A total of 101 MRIs were initially evaluated. The ALL was not characterized in 13 (12.8%) examinations, resulting in 88 (87.1%) cases of injury evaluation. Of these, 55 (54.4%) patients had a normal ALL, and 33 (32.6%) showed signs of injury. Among the cases with injury, 24 (72%) patients showed proximal lesions, 7 (21%) showed distal lesions, and 2 (6.0%) patients presented both proximal and distal lesions. The meniscal portion of the ALL appeared abnormal in 16 (48%) patients. No relationship was found between ALL injury and lateral meniscus injury. CONCLUSIONS: Based on MRI analysis of acute ACL injuries with bone bruising of the lateral femoral condyle and lateral tibial plateau, approximately a third demonstrated ALL injuries of which the majority was proximal. LEVEL OF EVIDENCE: Level IV, case series.

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 spin-echo 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-T MRI 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.

Evaluation of the anterolateral ligament of the knee by means of magnetic resonance examination.

OBJECTIVE: To evaluate the presence of the anterolateral ligament (ALL) of the knee in magnetic resonance imaging (MRI) examinations. METHODS: Thirty-three MRI examinations on patients' knees that were done because of indications unrelated to ligament instability or trauma were evaluated. T1-weighted images in the sagittal plane and T2-weighted images with fat saturation in the axial, sagittal and coronal planes were obtained. The images were evaluated by two radiologists with experience of musculoskeletal pathological conditions. In assessing ligament visibility, we divided the analysis into three portions of the ligament: from its origin in the femur to its point of bifurcation; from the bifurcation to the meniscal insertion; and from the bifurcation to the tibial insertion. The capacity to view the ligament in each of its portions and overall was taken to be a dichotomous categorical variable (yes or no). RESULTS: The ALL was viewed with signal characteristics similar to those of the other ligament structures of the knee, with T2 hyposignal with fat saturation. The main plane in which the ligament was viewed was the coronal plane. Some portion of the ligament was viewed clearly in 27 knees (81.8%). The meniscal portion was evident in 25 knees (75.7%), the femoral portion in 23 (69.6%) and the tibial portion in 13 (39.3%). The three portions were viewed together in 11 knees (33.3%). CONCLUSION: The anterolateral ligament of the knee is best viewed in sequences in the coronal plane. The ligament was completely characterized in 33.3% of the cases. The meniscal portion was the part most easily identified and the tibial portion was the part least encountered.

OBJETIVO: Avaliar a presença do ligamento anterolateral (LAL) do joelho em exames de ressonância magnética (RM). MÉTODOS: Foram avaliadas 33 RM de joelho de pacientes feitas por indicações não relacionadas a instabilidade ligamentar ou trauma. Foram obtidas imagens no plano sagital ponderadas em T1 e imagens nos planos axial, sagital e coronal ponderadas em T2 com saturação de gordura. As imagens foram avaliadas por dois radiologistas experientes em patologias musculoesqueléticas. Na avaliação da visualização, dividimos a análise do ligamento em três porções: origem femoral até o seu ponto de bifurcação, da bifurcação até a inserção meniscal e da bifurcação até a inserção tibial. Considerou-se com variável categórica dicotômica (sim ou não) a capacidade de visualizar o ligamento em cada uma das porções e no seu todo. RESULTADOS: O LAL foi visualizado com característica de sinal semelhante às demais estruturas ligamentares do joelho, com hipossinal em T2 com saturação de gordura. O principal plano em que o ligamento foi identificado foi o coronal. Alguma porção do ligamento foi visualizada com clareza em 27 (81,8%) joelhos. A porção meniscal ficou evidente em 25 (75,7%) dos joelhos, a porção femoral em 23 (69,6%) e a tibial em 13 (39,3%). As três porções foram visualizadas em conjunto em 11 (33,3%) joelhos. CONCLUSÃO: O ligamento anterolateral do joelho é mais bem visualizado em sequências no plano coronal. O ligamento foi caracterizado por completo em 33,3% dos casos. A porção meniscal foi a mais facilmente identificada e a tibial a menos encontrada.

Evaluation of the anterolateral ligament of the knee by means of magnetic resonance examination / Avaliação do ligamento anterolateral do joelho por meio de exame de ressonância magnética

OBJECTIVE: To evaluate the presence of the anterolateral ligament (ALL) of the knee in magnetic resonance imaging (MRI) examinations. METHODS: Thirty-three MRI examinations on patients' knees that were done because of indications unrelated to ligament instability or trauma were evaluated. T1-weighted images in the sagittal plane and T2-weighted images with fat saturation in the axial, sagittal and coronal planes were obtained. The images were evaluated by two radiologists with experience of musculoskeletal pathological conditions. In assessing ligament visibility, we divided the analysis into three portions of the ligament: from its origin in the femur to its point of bifurcation; from the bifurcation to the meniscal insertion; and from the bifurcation to the tibial insertion. The capacity to view the ligament in each of its portions and overall was taken to be a dichotomous categorical variable (yes or no). RESULTS: The ALL was viewed with signal characteristics similar to those of the other ligament structures of the knee, with T2 hyposignal with fat saturation. The main plane in which the ligament was viewed was the coronal plane. Some portion of the ligament was viewed clearly in 27 knees (81.8%). The meniscal portion was evident in 25 knees (75.7%), the femoral portion in 23 (69.6%) and the tibial portion in 13 (39.3%). The three portions were viewed together in 11 knees (33.3%). CONCLUSION: The anterolateral ligament of the knee is best viewed in sequences in the coronal plane. The ligament was completely characterized in 33.3% of the cases. The meniscal portion was the part most easily identified and the tibial portion was the part least encountered. .

OBJETIVO: Avaliar a presença do ligamento anterolateral (LAL) do joelho em exames de ressonância magnética (RM). MÉTODOS: Foram avaliadas 33 RM de joelho de pacientes feitas por indicações não relacionadas a instabilidade ligamentar ou trauma. Foram obtidas imagens no plano sagital ponderadas em T1 e imagens nos planos axial, sagital e coronal ponderadas em T2 com saturação de gordura. As imagens foram avaliadas por dois radiologistas experientes em patologias musculoesqueléticas. Na avaliação da visualização, dividimos a análise do ligamento em três porções: origem femoral até o seu ponto de bifurcação, da bifurcação até a inserção meniscal e da bifurcação até a inserção tibial. Considerou-se com variável categórica dicotômica (sim ou não) a capacidade de visualizar o ligamento em cada uma das porções e no seu todo. RESULTADOS: O LAL foi visualizado com característica de sinal semelhante às demais estruturas ligamentares do joelho, com hipossinal em T2 com saturação de gordura. O principal plano em que o ligamento foi identificado foi o coronal. Alguma porção do ligamento foi visualizada com clareza em 27 (81,8%) joelhos. A porção meniscal ficou evidente em 25 (75,7%) dos joelhos, a porção femoral em 23 (69,6%) e a tibial em 13 (39,3%). As três porções foram visualizadas em conjunto em 11 (33,3%) joelhos. CONCLUSÃO: O ligamento anterolateral do joelho é mais bem visualizado em sequências no plano coronal. O ligamento foi caracterizado por completo em 33,3% dos casos. A porção meniscal foi a mais facilmente identificada e a tibial a menos encontrada. .