Assessment Micro-anatomy of the Menisci and Cartilage After Isolated Acute ACL Injury With MRI at 7T

Assessment of the Micro-anatomy of the Menisci and Cartilage in Patients With Presumed Isolated Acute Anterior Cruciate Ligament Injury With Ultrahigh Field MRI at 7T

Study population The investigator set the sample size to 200 patients.

Primary outcome

• Diagnostic accuracy of ultrahigh field MRI (T7) compared to high field MRI (T3 or less) for detection of meniscal injuries associated with acute ACL injury Secondary outcome
• Influence of 1) Location of injury and 2) meniscal tear pattern (modified WORMS18,19) on the sensitivity of high field MRI compared to ultrahigh field MRI for detection of meniscal tears

However, there is no evidence that ACL reconstruction can actually prevent the development of knee osteoarthritis. However, concomitant meniscal injuries, either at the time of the ACL injury or secondary to the ACL injury, significantly increase the risk of secondary knee osteoarthritis. Therefore, the treatment strategy for ACL injuries is strongly influenced by the presence of concomitant meniscal injuries on initial magnetic resonance imaging (MRI).

To achieve higher spatial resolution and faster image acquisition, there is a clear trend toward higher field strength MRI.

Meniscal injuries repeatedly occur during the course after isolated ACL ruptures, and the question is whether these injuries occurred during the original trauma or as a result of the torn ACL.

Therefore, the primary objective of the current study was to evaluate the potential utility of ultrahigh-field MRI (T7) in detecting occult meniscal tears or cartilage injuries associated with presumed isolated acute ACL injuries compared with high-field MRI (T3 or less). The secondary objective was to evaluate the influence of meniscal tear location and meniscal tear pattern on the sensitivity of high-field MRI compared with ultrahigh-field MRI in detecting meniscal tears. Subsequently, different orthopedic surgeons and radiologists will evaluate the images.

Inclusion Criteria:

• Presumed isolated, acute rupture of the anterior cruciate ligament (trauma not older than 4 weeks) diagnosed by high-field MRI (3 Tesla or less) at Balgrist.
• Written informed consent of the study participant
• Age 18 years or older

Exclusion Criteria:

• Previous knee surgery or trauma
• Presence of concomitant meniscal injury on high-field MRI (3 Tesla or less)
• Advanced gonarthrosis (Kellgren-Lawrence score greater than 2).
• Contraindication to the performance of MRI
• Unsigned informed consent
• Inability to follow study procedures (e.g., due to cognitive impairment) or inadequate knowledge of project language
• Pregnancy