Mallet finger (illustration)

Case contributed by Andrew Murphy

Presentation

Forced flexion of the DIP

Bony avulsion mallet injury

Diagram

The following are a series of images depicting a forced flexion event of the DIP. The DIP is forced into sudden flexion resulting in an avulsion fragment at the insertion of the common extensor tendon on the dorsal aspect of the distal phalanx at the DIP joint.

Mid-tendon mallet injury

Diagram

The following are a series of images depicting a forced flexion event of the DIP. In this case, it is a mid-tendon injury, rather than a bony avulsion.

Case Discussion

Mallet finger is an injury to the extensor mechanism of the finger at the level of the distal interphalangeal joint, it occurs due to forced flexion of the DIP (stubbing your finger). Sometimes it can be bony (an avulsion at the insertion of the common extensor tendon) others it can be purely a mid tendon injury.

Clinically they both present with the finger in fixed flexion ( inability to extend the finger at the DIP joint).

Above is a simplified illustration of the mechanism leading to either a bony avulsion of mid-tendon injury,

How to use cases

You can use Radiopaedia cases in a variety of ways to help you learn and teach.

Creating your own cases is easy.

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.