What is it?
A mallet finger, also known as baseball or droop finger, happens when there is a direct blow to the fingertip or when the finger gets jammed and is forcefully bent. This common hand injury is often seen in ball sports, after a fall, or from something as simple as tucking sheets under a mattress. This results in damage to the tendon responsible for straightening the end joint of your finger. The deformity often appears very quickly, leaving you with the tip of your finger drooping down and the inability to straighten the end joint. The finger then looks like… a mallet.
There are two types of mallet fingers:
· Type 1 is caused by a ruptured or torn tendon
· Type 2 is caused by the tendon pulling off the bone and causing an avulsion fracture (small piece of bone pulling off the main bone)
As with most traumatic acute injuries, the finger will often swell up quickly and may be painful to touch or to move. Being such a small injury in terms of size of the affected body part, people often ignore it assuming it’s only a sprain that will fix itself. A mallet finger might look like a simple injury, but it can actually be tricky to treat.
What do I do about it?
Most mallet finger injuries can be treated conservatively (without surgery). The number one rule with this injury is that the fingertip must be kept perfectly straight for 6 to 8 weeks. This period of immobilization allows for the tendon (type 1) or the bone (type 2) to heal. The extensor tendon is very thin and fragile which is why strict immobilization is crucial. Just a few degrees of movement can undo any amount of tendon or bone healing that has occurred and can lead to poor outcomes.
Immobilization can be done in various ways including custom orthoses, over-the-counter splints and even the good old popsicle stick!
Custom orthoses offer the best positioning and fit as they are molded directly to your finger and can be adjusted as your swelling comes down. The immobilization method only needs to include the end joint of your finger. Most over-the-counter splints are too long for the average finger and can cause unnecessary stiffness to other joints. Regardless of the method you choose, make sure to remove your splint daily to clean your finger and remember to always keep it straight!
In some instances, the avulsion fracture might be too large or too displaced to heal conservatively. An assessment by a plastic surgeon is then needed to look at surgical options to restore proper bone alignment.
What if I don’t treat it?
The biggest issue is that your fingertip will always be bent and might end up fixed in that position. Think about trying to put your hand in your pocket or wiping a table with a droopy fingertip… it gets annoying and potentially dangerous. Imbalances may also develop in your finger creating further deformities. It’s also important to note that there is a timeframe within which a mallet finger can be treated. The longer you wait to have it treated, the lower the success rate is. You might as well do it right from the beginning by having a certified hand therapist assess your injury and determine the best course of action to get you back to what matters!
References
1. Lovy, A.J. Elhassan B.T (2021) Surgical Management of Extensor Tendon Injuries. Rehabilitation of the Hand and Upper Extremity (7th edition, Volume 1, pages 442-463). Philadelphia: Elsevier, Inc.
2. Cannon, N., Mart, S., et al. (2020) Diagnosis and Treatment Manual for Physicians & Therapists. 5th ed. Vol 3. Indiana Hand to Shoulder Institute