This is a 48-year-old man who fell nine months ago and now has swelling and pain in the right index finger.
- What do the paired arrows label in image 1?
- What does the single arrow label in image 1?
- What does the single vertical arrow label in image 2?
- What do the sets of three paired arrows label in image 2?
- With image three, what do you think is the patient’s story?
- The paired arrows point to a torn ulnar collateral ligament in the first image.
- The single long arrow points to periosteal perpendicular reaction (first image).
- The single vertical arrow (second image) points to an inflamed irregular destructive erosion.
- The multiple short-axis arrows on T1 coronal imaging (second image, three paired arrows) point to extensive periosteal reaction.
- The most plausible explanation for what has happened to this finger is a traumatic injury leading to instability, cartilage injury and collateral ligament injury resulting in chronic indolent infection of the joint space. To back this up, see short-axis axial T2 in which arrows point to a large proteinaceous palmar effusion (short-axis T2 arrows, third image).
- For more case review, head to MRI Online.