[Magnetic resonance arthrography indications and technique (II). Lower limb]

Area of Science:

• Radiology
• Orthopedics
• Medical Imaging

Context:

• Magnetic resonance (MR) is the primary imaging modality for articular pathology.
• Conventional MR imaging can present diagnostic challenges for certain joint conditions.
• MR arthrography (MRA) involves direct joint puncture with intra-articular contrast injection.

Purpose:

• To review the current utility of MR arthrography (MRA) in evaluating hip, knee, and ankle joints.
• To highlight MRA's role in improving diagnostic reliability for articular and periarticular pathologies.
• To discuss MRA's advantages over conventional MR imaging in specific clinical scenarios.

Summary:

• MRA improves diagnostic accuracy by distending the capsular recess and delineating intra-articular structures.
• It enhances the evaluation of difficult-to-assess annexed structures, improving reliability.
• MRA helps resolve diagnostic problems, potentially avoiding unnecessary diagnostic arthroscopy and guiding therapeutic plans.

Impact:

• MRA has established indications for major lower extremity joints, including hip labral tears, post-operative knee meniscus evaluation, and ankle impingement syndromes.
• The technique is valuable for diagnosing osteochondral injuries, loose intra-articular bodies, and synovial pathology across various joints.
• MRA enhances the diagnostic capability of MR imaging, leading to more precise patient management and treatment strategies.