Mallet Finger

The extensor tendon of the finger can become injured, usually through a sudden forced flexion of the distal interphalangeal joint (DIP), for example, when a ball hits the tip of a finger.

The common presentation of this injury is an individual who can not straighten (extend) the DIP joint of a finger. There may or may not be associated pain and swelling at the DIP joint. In fact, it is not uncommon for a person to remark how they didn’t know the finger had been injured until it was noticed that it could not be fully straightened.

On x-ray, there may be an associated avulsion fracture where the terminal extensor tendon joins onto the distal phalanx, known as a “bony mallet”. When there is no fracture, it is referred to as a “soft tissue mallet”.

The accepted treatment for either a bony or soft tissue mallet injury is positioning of the DIP joint of the finger in slight hyper-extension for a minimum of 6 uninterrupted weeks, but optimally 8 weeks uninterrupted. This is best achieved through provision of a custom fitted thermoplastic splint. Although the “stax splints” are readily available, the fit is often not acceptable, not extending the DIP joint sufficiently, or interfering with full PIP joint motion. The alumifoam splints can position the DIP more carefully, but can create skin maceration from excess moisture collection.

The Certified Hand Therapists at the Hand Therapy Centres (www.handtherapycentres.com) treat many clients with mallet injuries. Evidence shows that the following needs to be in place to result in the best outcome from this injury:
1. If patients are sufficiently educated about their injury they will be more likely to comply with the exacting splinting regime.
2. Custom splints need to be comfortable, adequately position the finger and allow for the individual to participate in work and leisure activities.
3. Finally, monitoring of the patient while they are weaning out of the splint minimizes the risk of the extensor lag from re-occurring.


Secondary complications of poor management include:
• Swan neck deformity;
• Continued pain;
• Patient unhappy with range of motion;

The best results occur when treatment is started promptly, within a few days of injury. However, full functional range of motion of the DIP has been restored in some patients even when treatment has been delayed for several months.

On average, patients attend three sessions for treatment of mallet finger injuries, (once for the initial splinting and patient education; at 6 or 8 weeks of splinting to start the weaning process and final visit during the end of the weaning process to ensure an excellent outcome). The total cost of these visits is reimbursable from most extended care insurance plans.

If you have any questions in regards to the treatment of Terminal Extensor Injuries, pleas feel free to contact us and speak to one of our Certified Hand Therapists.