Ever jam your finger into something and it hurts for a while, but then the hurt goes away? It is likely because you sprained a ligament. Ever jam your finger and it hurts for a while, and then you realize you can’t straighten it all the way? If so, chances are you have Mallet Finger.
Mallet finger is a deformity that is associated with a fracture that happens at the tip of your finger. Common causes are being struck by a basketball, volleyball, softball, or something of a similar nature. It can even be caused by aggressively tucking in bed sheets. A direct strike or blow to the top of the finger or a more traumatic crush injury can be its cause.
The reason why the tip of the finger bends and can no longer straighten when this happens is because the fracture causes a disruption in the extensor mechanism of the hand and fingers. The particular part of the mechanism affected, in regards to Mallet finger, is the central slip. This piece of soft tissue connects the muscle that extends the tip of your finger to the bone known as the distal phalanx.
The common treatment for a mallet finger is continuous extension splinting. The idea is to reset the bones so that they can heal properly together again, giving the soft tissue a support structure for proper movement. Splinting of the involved finger can be for 6-10 weeks. The range given is a large period of time, because in a healthy middle aged individual it takes about 8 weeks for bone to heal. Factors such as age, nutrition, alcohol use, tobacco use, and diabetes are just some of the factors that can change the outcomes of tissue healing or the length of time required for healing.
What must be stressed is that with extension splinting for mallet finger, wearing the splint must be constant. If at 3 weeks a patient takes their splint off to do something, letting the finger bend, then that 6-10 week clock starts all over again, because they essentially let their distal phalanx bone re-fracture itself.
In some cases, an untreated mallet finger can cause another problem called a Swan Neck deformity. This deformity has more functional consequences because not only will the tip of the finger not straighten, but the middle part of the finger is stuck in hyperextension and will not bend. However, in most cases an untreated mallet finger primarily just causes what is called an extension lag. Basically, this means that the finger won’t straighten. This is largely a cosmetic issue and poses no functional consequence. With that note, why would you want to walk around with a finger that won’t straighten all the way if it is easily and non-invasively fixable?
If you find yourself in the predicament of noticing that the tip of your finger won’t straighten, go see your orthopaedist or come to PhysioDC where we can help you out.