The Diagnostic Validity of Magnetic Resonance Imaging in Acute Knee Injuries With Hemarthrosis: A Single-Blinded Evaluation in 69 Patients Using High-Field MRI Before Arthroscopy

Abstract

Sixty-nine patients with traumatic knee hemarthrosis were evaluated an average of 3 days after trauma by high field (1.5T) magnetic resonance imaging (MRI) using sagittal T1, T2-weighted and coronal 3D-gradient echo images. All knees were arthroscopically examined shortly afterwards. The diagnostic validity of MRI for intraarticular pathology was determined using arthroscopy as golden standard. All patients had pathological findings on arthroscopy. The injuries were sports-related in 77% of the cases. MRI was highly sensitive (86%) and specific (92%) for diagnosis of anterior cruciate ligament tears. Diagnosis of medial meniscal tears showed a 74% sensitivity and 66% specificity. MRI detected lateral meniscal tears in 50% with an 84% specificity. As such, MRI missed 10 significant meniscus ruptures requiring surgical treatment. The sensitivity for partial or total medial collateral ligament tears was 56%, the specificity 93%. Rupture of the medial retinaculum in cases with patellar dislocation or significant damage of articular cartilage were only detected by MRI in a few cases (27% and 20% sensitivity, respectively). MRIs low diagnostic validity for intraarticular pathology with hemarthrosis may be attributed to the shifting paramagnetic properties of the blood remains and catabolic processes in meniscal and chondral tissues during the hemoglobin degradation process. Accordingly, MRI, with the technique used, could neither replace arthroscopy in the diagnosis and screening of acute knee injuries, nor select patients with need for immediate arthroscopic meniscal surgery.

Clinical, MRI, and arthroscopic correlation in meniscal and anterior cruciate ligament injuries

“…Jee et al concluded that MRI in the presence of ACL tears has lower sensitivity for detecting meniscal tears due to missed lateral meniscal tear [7]. Lundberg et al found sensitivity and specificity of 74% and 66%, respectively, for medial and 50% and 84% for lateral meniscus [10]. They found that MRI could not replace arthroscopy in diagnosis of acute knee injuries.…”

Efficacy of Magnetic Resonance Imaging Evaluation for Meniscal Tear in Acute Anterior Cruciate Ligament Injuries

“…17,18 Only a few studies were reported, and they were not comparative studies. Regarding the diagnostic validity of MRI in acute knee injuries, Lundberg et al 24 suggested that the low diagnostic accuracy of MRI for intra-articular pathologic conditions with hemarthrosis may be attributed to catabolic processes in meniscal and chondral tissues during the hemoglobin degradation process.…”

Traumatic knee extension deficit (the locked knee): can MRI reduce the need for arthroscopy?

“…Our results show that the sensitivity and specificity of MRI for diagnosing meniscus lesions (76%) [2,16,17]. A high NPV means that a negative MRI is reliable and this would justify an expecting approach instead of subacute surgery.…”

“…It is known to have high sensitivity and specificity for ACL-tears and lesions of the medial meniscus [2,10,11], although there are also false-positive results [12,13].…”