A mallet finger happens when the extensor tendon to the distal joint of the finger is stretched or torn. The extensor tendon is on the top of the finger. The distal joint is the last joint near the tip of the finger. This injury sometimes includes a small fracture of the finger.
Bones, Tendons, and Muscles of the Hand
The most common cause of a mallet finger is when the tip of a finger is forcibly jammed into flexion or hit against a solid object. It occurs often in sports, such as baseball and basketball, when a ball hits the end of an extended finger. This injury causes the tendon on the back of the finger to be partially or completely torn. The tendon can no longer fully extend the distal joint.
A risk factor is something that increases your chance of getting a disease or condition. The primary risk factor for developing mallet finger is playing a sport or activity that exposes the finger to injury.
Symptoms of mallet finger include:
- Pain and tenderness at the distal finger joint after injury
- Swelling and redness around the distal joint after the injury
- Inability to completely extend the finger
Your doctor may take an x-ray of the injured finger to look for a small fracture extending into the joint. This fracture helps diagnose a mallet finger.
Treatment for mallet finger includes:
For the first one to two days, an ice pack should be applied 15-20 minutes at a time every three to four hours to reduce swelling and tenderness. Place a towel between the ice pack and your skin.
A splint is usually applied to the outermost joint of the finger. It keeps the finger extended and prevents it from moving during healing. The splint should be worn for 4-6 weeks. If you move the injured distal joint, you have to restart the immobilization time period. Following instructions for splint use is important for this injury.
You may need physiotherapy after the splint is removed. These exercises will help improve strength, flexion, and extension of the injured finger.
In some cases, surgery may be required. This may be the case if there is a total tear of the extensor tendon. It may also be needed if there is a fracture extending into the joint where the tendon has pulled a piece of bone loose.
With or without surgery, mallet fingers often result in some minor drooping of the distal finger joint. However, you should have close to normal function and be able to play sports.
The only way to prevent mallet finger is to avoid injury to your finger.
American College of Sports Medicine
American Physical Therapy Association.
Canadian Orthopaedic Association
Canadian Rheumatology Association
Acute Finger Injuries: Part I. Tendons and Ligaments. American Family Physician. 2006 March 73(5):810-816.
Anderson D. Mallet finger—management and compliance. Aust Fam Physician. 2011 Jan–Feb;40(1-2):47-48.
Handoll HH, Vaghela MV. Interventions for treating mallet finger injuries. Cochrane Database Syst Rev. 2004;(3):CD004574.
Mallet finger. EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed. Updated May 6, 2014. Accessed August 18, 2014.
Last reviewed August 2015 by Warren A. Bodine, DO, CAQSM
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.