Mallet finger

Definition

A mallet finger is the inability to straighten the distal phalange of a finger. This condition may lead to a deformity of the phalange, which remains permanently bent towards the palm.

Pathology

A mallet finger is the result of the rupture of the finger extensor tendon at the distal inter-phalangeal (DIP) joint. This condition is also called baseball finger, as it is common in baseball players. Sometimes the rupture of the finger extensor tendon occurs in combination with a fracture of the distal phalange. Consequently the patient is unable to completely straighten the finger.

Causes

A mallet finger is more commonly observed in ball sport injuries but can also arise from daily activities that do not require a strong force. It typically ensues when the ball hits the straight finger forcing it to bend forward.

Risk factors

A mallet finger is most common among players of ball games such as:

Baseball

Basketball

Netball

Football

Rugby

Daily activities

Symptoms

The symptoms arising from a mallet finger are:

Sudden pain at time of injury

Swelling around the DIP joint

Bruising

Blood accumulation within the nail bed

Nail loss

Finger stiffness

Inability to completely extend the finger

Typical finger deformity

Diagnosis

The medical history focuses on the mechanisms of injury leading to mallet finger. Medical examination is usually sufficient for the diagnosis and includes:

Detection of finger deformity

Palpation to the region of interest

Test changes in the range of movement of the finger distal phalanges, both passively and actively

X-rays in case of suspected avulsion fracture of the phalange.

Treatment

Nonoperative treatment

Management of the mallet finger is normally achieved conservatively if no fracture or other complications are present. Conservative treatment includes the immobilisation with a splint to keep the finger in full extension for up to 6 - 8 weeks and another 6 weeks of night use of the splint. Additional treatments include:

Ice pads

Administration of NSAIDs

Painkillers

Rehabilitation

A physical or occupational therapist guides the patient through an exercise plan to restore flexibility and strength of the finger affected by mallet pathology. Education will inform how to modify activities to avoid recurrent finger injuries. Additional rehabilitative therapy includes:

Joint mobilisation

Stretches  

Electrotherapy

Prevention

Prevention of a mallet finger aims at reducing the risk of future injuries to the extensor tendons by protecting fingers during physical activities and sport. Common strategies are:

Finger splinting

Finger taping