This 54-year-old male complains of chronic right index finger pain with no reported injury. Be sure to look at the three images without arrows before looking at the same images with arrows.
A. What has likely happened to this patient?
B. What does the red arrow on image 4 point to?
C. What does the green arrow on image 4 indicate?
D. What do the orange arrows on image 5 signify?
E. Finally, the pink arrows on image 6?
A. The patient dislocated his finger at the second metacarpophalangeal (MCP) joint resulting in significant capsular injury.
B. Volar subluxation of the second proximal phalanx.
C. Torn volar (palmar) plate proximally with disruption of the check rein ligaments.
D. Edema/partial tearing of the sagittal bands of the extensor hood.
E. Sprain of both the radial and ulnar collateral ligaments.
This is a complicated case which provides a good review of the MCP capsular anatomy, along with a healthy reminder to not be afraid to question the supplied history when the imaging findings are not concordant with that history. For more case review, check out MRI Online.