A dynamic study of the anterior cruciate ligament of the knee using an open MRI
- 300 Downloads
Recent anatomical and radiological studies of the anterior cruciate ligament (ACL) suggest the ACL length and orientation change during knee flexion, and an open MRI sequencing during knee flexion enables a dynamic ACL analysis. This study’s goal is to describe a normal ACL using a 1T open MRI and, in particular, variations in length and insertion angles at different degrees of flexion. Twenty-one volunteers with clinically healthy knees received a dynamic MRI with their knees in hyperextension, neutral position, and flexed at 45° and 90° angles. For each position, two radiologists measured the ACL lengths and angles of the proximal insertion between the ACL’s anterior edge and the roof of the inter-condylar notch. Additionally, we measured the ACL’s and the tibial plateau’s distal angle insertion between their anterior edges and then compared these with the nonparametric Wilcoxon test. The ACL had a significant extension between the 90° flexion and all other positions (hyperextension: 31.75 ± 2.5 mm, neutral position: 32.5 ± 2.6 mm, 45°: 35.6 ± 1.6 mm, 90°: 35.6 ± 1.6 mm). There was also a significant increase of the angle insertion between the proximal 90° flexion and all other positions, as well as between hyperextension and bending to 45° (hyperextension: 2.45° ± 3.7°, neutral: 13.4° ± 9.7°, 45°: 33 25 ± 9.3, 90: 51.85° ± 9.3°). Additionally, there is a significant increase in the distal angle insertion for all positions (hyperextension: 133.2° ± 5.4°, neutral position: 134.95° ± 4.4°, 45°: 138.35° ± 5.9°, 90°: 149.15° ± 8.6°). Our study is the first to exhibit that a dynamic MRI has a significant ACL extension in vivo during bending. This concept opens the way for further studies to improve the diagnosis of traumatic ACL injuries using a dynamic MRI.
KeywordsDynamic MRI Anterior cruciate ligament Knee Open field Anatomy
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
- 2.Arnoldi AP, Weckbach S, Nussbickel C, Horng A, Nöbauer I, Zysk S, Reiser M, Glaser C (2011) MRI based volumetric assessment of knee cartilage after ACL-reconstruction, correlated with qualitative morphologic changes in the joint and with clinical outcome. Is there evidence for early posttraumatic degeneration? Rofo 183:1138–1144. doi: 10.1055/s-0031-1281685 CrossRefPubMedGoogle Scholar
- 14.Mink JH, Reicher MA, Crues JV III, Deutsh AL (1987) MRI of the knee, 2nd edn. Raven, New York, NY, pp 145–162Google Scholar
- 20.Sbihi A, Frank A, Dorfmann H (2006) Arthroscopie:genou, cheville, hanche, épaule, coude, poignet, extra-articulaire. Anatomie du ligament croisé antérieur et isométrie, 2nd edn. Elsevier, ParisGoogle Scholar