MR Imaging Knee Synovitis and Synovial Pathology.

Area of Science:

• Radiology
• Orthopedics
• Medical Imaging

Background:

• Knee synovitis is a common MR imaging finding in patients with knee pain.
• Causes include post-traumatic, osteoarthritis, inflammatory, and infectious conditions.
• Synovial thickening, effusion, and enhancement are nonspecific across etiologies.

Purpose of the Study:

• To review synovial physiology and MR imaging of the normal synovium.
• To discuss MR imaging findings in synovitis.
• To identify specific pathologies and subtle signs differentiating diagnoses.

Main Methods:

• Review of current literature on knee synovitis and MR imaging.
• Discussion of synovial physiology and normal synovial appearance on MRI.
• Analysis of MR imaging features associated with various synovitis causes.

Main Results:

• Synovial thickening, joint effusion, and enhancement are common but undifferentiating features of synovitis.
• Intravenous contrast administration aids in differentiating synovial proliferation from joint fluid.
• Specific imaging findings may suggest certain underlying pathologies, but differentiation is often limited.

Conclusions:

• MR imaging is crucial for evaluating knee synovitis.
• While contrast-enhanced MRI helps assess synovial proliferation, differentiating specific causes of synovitis remains challenging.
• Further research may identify more specific imaging biomarkers for knee synovitis.