Massage therapy · Kitchener–WaterlooMallet Finger (Baseball Finger)
Elbow, Wrist & Hand
What It Is
Mallet finger is a finger deformity caused when the extensor tendon is damaged. This is the thin tendon responsible for straightening the end joint of the finger or thumb. When a ball or other hard object strikes the tip of the finger or thumb and forces it to bend further than it should, the force can tear the tendon or pull it away from the bone. Sometimes a small piece of bone is pulled away along with the tendon (AAOS, n.d.; Medway NHS Foundation Trust, 2019). The fingertip droops and cannot be straightened on its own; it will only straighten if you push it up with your other hand (AAOS, n.d.). It has also been termed baseball finger.
The finger will often be painful, bruised and swollen from the injury, and the tip of the finger will droop noticeably. Sometimes blood will collect beneath the nail, or the nail may come away from the skin underneath it (AAOS, n.d.).
The injury usually happens when something strikes the end of the finger directly, such as a baseball or other hard ball hitting it, or hitting the finger with a mallet.
Mallet Finger (Baseball Finger) Anatomy
All of the fingers have three bones in them, while the thumb only has two. At each of the joints, the bones are held in place by ligaments. Muscles in the forearm and hand turn into tendons, which attach to the finger bones, and it is the muscles that move the fingers by pulling on the tendons. The extensor tendons on the top of the hand straighten the fingers and thumb (AAOS, n.d.). The finger bones join onto the five metacarpal bones, the long bones in the palm of the hand.
Not a diagnosis — for more information, contact me or another trusted healthcare provider.
Treatment
Self-Care & Treatment
How to Treat Mallet Finger (Baseball Finger)
Treatments you may want to discuss with your family doctor or nurse practitioner
Tips
- To prevent the injury in the first place, take care whenever you take part in any activity, especially sport.
- If you have been given a splint, wear it exactly as instructed by your clinician. The fingertip must be kept straight at all times, including whenever the splint is taken off for washing or skin care, by supporting it with your other hand. If the fingertip droops, healing can be disrupted and you may need to wear the splint for longer (AAOS, n.d.; Medway NHS Foundation Trust, 2019).
- If you have a cut on the finger as well, cover it with a clean dressing and get it checked straight away (NHS, 2025; AAOS, n.d.).
- Your doctor may arrange extra appointments to check on your progress (AAOS, n.d.).
- In children, a mallet finger injury can involve the area that controls bone growth, so a doctor must check and treat it carefully (AAOS, n.d.).
- Take care when playing baseball to make sure a flying ball doesn't injure your finger and cause the condition.
Treatment
My Approach
A mallet finger heals while the fingertip is held straight in a splint, and your doctor or hand therapist decides how it's splinted and for how long. I work within their plan and don't take the splint off unless they've said it's safe. If you've had a pin or surgery, I need your surgeon's okay before any hands-on treatment.
Please bring any X-ray reports and notes from your medical team to your first visit. They're an important part of planning safe treatment for you.
I assess how your hand, wrist, forearm and shoulder are moving and coping, and check the skin around the splint.
While You're in the Splint
- Easing the hand, forearm, shoulder and neck, which tense up when you guard a sore finger
- Keeping your other joints moving, as your clinician allows
- Gentle lymphatic drainage and keeping your hand raised to help with swelling
- Going over how to keep the fingertip straight whenever the splint is off
Once It Has Healed
- Warm applications and gentle work along the tendon, never cross-fibre frictions on the healing tendon
- Scar work once any wound has fully healed
- Gentle, gradual bending of the fingertip; if it starts to droop again, we stop and check with your clinician
- Grip and pinch strength, then a return to sport with taping at first; I'll show you how to tape it yourself
What to Expect
Typical Course
What I Focus On
Please read
When to See a Doctor First
When to Get Help
A mallet finger needs medical treatment to help the finger regain as much function as possible, and most doctors recommend getting it treated within a week of the injury (AAOS, n.d.).
Go to the emergency room at your nearest hospital straight away (call 911 if you cannot get there safely) if there is blood beneath the nail or the nail has come away. This may be a sign of a cut in the nail bed, or that the bone is broken and the wound goes down to the bone (an open fracture), which puts you at risk of infection (AAOS, n.d.). Also get emergency help if the finger is pointing at an odd angle, looks blue or feels numb, or you can see bone through a cut (NHS, 2025).
Sources
References
- American Academy of Orthopaedic Surgeons (n.d.) Mallet finger (baseball finger). OrthoInfo. Available at: https://orthoinfo.aaos.org/en/diseases--conditions/mallet-finger-baseball-finger/ (Accessed: 7 October 2026).
- Medway NHS Foundation Trust (2019) Discharge advice following attendance with a 'mallet finger' injury. Available at: https://www.medway.nhs.uk/uploads/2024/04/Mallet-Finger-Patient-Information-Leaflet.pdf (Accessed: 7 October 2026).
- NHS (2025) Broken finger or thumb. Available at: https://www.nhs.uk/conditions/broken-finger/ (Accessed: 8 October 2026).