A smashed fingernail, medically known as a subungual hematoma, occurs when blood collects underneath the nail plate due to direct trauma. This common injury often results from incidents like slamming a finger in a door or hitting it with a hammer. While painful due to pressure from trapped blood, these injuries are typically not serious and can often be managed with home care.
First Aid for a Smashed Fingernail
Immediate action after smashing a fingernail can help reduce pain and swelling. Begin by applying a cold compress or ice pack wrapped in a cloth to the injured finger for about 20 minutes at a time, repeating every two hours on the day of the injury. This cold application helps to minimize bleeding and prevent a blood blister from forming under the nail. Elevating the injured hand above the level of the heart also reduces blood flow to the area, decreasing inflammation and throbbing pain.
If there is any broken skin around the nail, gently clean the wound with mild soap and water to prevent infection. Over-the-counter pain relievers, such as ibuprofen or acetaminophen, can help manage discomfort and reduce inflammation. Protect the injured finger with a loose bandage to prevent further trauma, ensuring it’s not wrapped too tightly to avoid impeding blood flow.
Understanding the Healing Process
Following a smashed fingernail injury, the nail will likely discolor (reddish, brownish, bluish, or black) due to trapped blood. This subungual hematoma causes pressure and pain, which typically subsides as the body reabsorbs the blood or the nail grows out. Over time, the pressure from accumulated blood may cause the nail plate to separate and eventually fall off, often within weeks.
A new fingernail grows from the nail matrix, the tissue at the base of the nail. Complete regrowth for a fingernail typically takes four to six months, but up to a year for toenails. If the nail detaches, keep the underlying nail bed clean and dry, covering it with a bandage for protection as the new nail emerges. Patience is important, as the new nail might initially exhibit irregularities if the nail bed was damaged.
When to See a Doctor
While many smashed fingernails can be treated at home, certain symptoms warrant medical attention. Seek professional care if:
- Severe pain that over-the-counter medication does not relieve.
- Signs of infection, such as increased redness, swelling, pus, warmth, or a fever.
- The nail is significantly detached from the nail bed, if there’s a deep cut, or if you suspect a bone fracture or deformity.
- The injury involves the nail matrix, which could lead to permanent nail deformity.
- Blood under the nail covers a large portion and causes persistent throbbing pain, which may require trephination to drain the blood and relieve pressure.
- The injury involves a child, who should be assessed by a medical professional.
Tips for Prevention
Preventing smashed fingernails involves mindfulness and precautions in situations where hand injuries are common. Being aware of your surroundings, especially when working with tools, heavy objects, or slamming doors, helps avoid accidents. Wearing appropriate protective gloves during activities like DIY projects or tasks involving machinery offers a barrier against impacts and crushes.
Tidy, clutter-free workspaces also reduce the risk of accidental impacts. Selecting properly fitting gloves suitable for the task (e.g., cut-resistant or impact-resistant) provides optimal protection without hindering dexterity. Consistent attention to hand safety significantly lowers the chances of such painful injuries.