Presentation
Trauma to the left thumb one day before the presentation. Complaining of pain and swelling at the radial side of the thumb MCP joint.
Patient Data
There is a bony avulsion from the radial side of the thumb proximal phalanx base. There is no dislocation/bone lesion.
There is a bony avulsion of the radial collateral ligament from the phalanx base which shows a corresponding defect. The ligament shows edema at the distal end. The proximal part of the ligament shows a normal echopattern. The ulnar collateral ligament is normal.
The contralateral asymptomatic radial collateral ligament was examined for comparison which shows a normal echopattern.
Case Discussion
A female had thumb trauma followed by pain and swelling on the radial side of the thumb MCP joint. The radiograph shows a bony avulsion at the proximal phalanx base on the radial side. The ultrasound shows a bony avulsion of the radial collateral ligament which is lying deep to the aponeurosis. Radial collateral ligament injury is less common than ulnar collateral ligament of the thumb.