A subungual hematoma refers to a collection of blood that forms underneath a fingernail or toenail. This condition typically arises from direct trauma to the nail, such as dropping a heavy object on the digit or a crushing injury like slamming a finger in a door. Repetitive stress, often seen in athletes due to ill-fitting footwear, can also cause blood vessels under the nail to rupture, leading to this accumulation. The blood becomes trapped in the confined space, resulting in discoloration and pressure.
Assessing Minor Cases and Self-Care
A minor subungual hematoma may present with mild pain and a small area of discoloration that does not cover a significant portion of the nail. If the blood collection is less than 25% of the nail area and pain is tolerable, self-care measures can often manage the symptoms.
Initial self-care involves applying the RICE method: Rest, Ice, Compression, and Elevation. Resting the affected finger or toe and avoiding further strain is important for healing. Applying an ice pack, wrapped in a cloth to prevent direct skin contact, for 10-15 minutes at a time can help reduce swelling and discomfort. Elevating the injured limb above the heart can also minimize blood pooling and swelling. Over-the-counter pain relievers, such as ibuprofen or acetaminophen, can be used to manage pain and inflammation.
When Professional Treatment Is Necessary
Professional medical attention becomes important when a subungual hematoma causes severe, throbbing pain or covers a large portion of the nail, typically exceeding 25% to 50% of its surface area. Indicators of a more serious injury include signs of infection like increasing redness, swelling, pus drainage, or fever, and suspected underlying damage such as a bone fracture or nail detachment.
For significant hematomas causing pain, a medical procedure called trephination may be performed to relieve pressure. This involves creating a small hole in the nail plate to allow the trapped blood to drain. Healthcare providers may use various sterile tools for this, including an electrocautery device, a needle, or a specialized trephine. This procedure, which should not be attempted at home, can offer immediate pain relief by decompressing the area.
What to Expect After Treatment
Following either self-care or professional drainage, recovery involves waiting for the injured nail to grow out. The discolored area will gradually move forward with new nail growth. This process can take several months, with fingernails typically growing out in about 6 to 9 months and toenails taking longer, sometimes 12 to 18 months, or even up to 2 years.
After professional drainage, it is important to keep the treated area clean and dry to prevent infection. Patients are often advised to avoid soaking the digit and to monitor for any signs of infection, such as increased warmth, redness, swelling, or purulent discharge. The nail may partially or completely detach due to the injury or pressure, and a new nail will regrow in its place. While the new nail is usually normal, severe damage to the nail bed could potentially lead to a malformed or thickened nail.
Preventing Future Hematomas
Preventing subungual hematomas involves protecting the fingers and toes from direct impact and repetitive stress. When working with heavy objects or in environments where foot injuries are common, wearing appropriate protective footwear, such as steel-toed boots, reduces risk. Exercising caution when closing doors or handling tools prevents crushing injuries.
For athletes, especially runners, ensuring shoes fit correctly prevents repetitive trauma to the nails. Shoes that are too tight can cause toes to repeatedly hit the front of the shoe, leading to bruising. Keeping toenails trimmed short and square minimizes friction and pressure within footwear.