Ultra-low-field magnetic resonance imaging of acute cruciate ligament tears

Ultra-low-field (0.04 T) magnetic resonance imaging (MRI) was evaluated in 15 patients with acute trauma to the knee and clinically suspected injuries of the cruciate ligaments. Subsequent arthroscopy was performed within 14 days (mean: 3 days) in 14 patients and after 3 mo in one patient. At arthroscopy/arthrotomy tears of the anterior cruciate ligament (ACL) were verified in 13 patients (11 complete, 2 partial tears). An additional tear of the posterior cruciate ligament (PCL) was found in one patient. All the tears could be demonstrated by MRI. There was one false positive MR diagnosis of ACL tear. It is possible with low-field MRI to diagnose injuries of the cruciate ligaments with good accuracy.