Subungual hematomas most commonly resolve without complication. If you were not evaluated at the time of the subungual hematoma, especially if severe, you should see your physician to be evaluated appropriately.
Subungual hematomas are classically caused by trauma, such as something heavy falling on the toe, stubbing the toe or some other sort of trauma. If there is no trauma associated, it is important to be examined by a physician, as there are several mimickers of hematoma. These include benign moles under the toenail, acral melanoma, and other types of tumors.
If a trauma was the enciting factor, the rest of the toe should be evaluated for fracture
or trauma that can not be seen externally. Plain x-rays would be able to assess for fraacture, even if some time has passed since the trauma.
Hematoma is caused by damage to the small vessels supplying the cuticle and nail bed. If there is significant trauma to the cuticle, this may cause permanent disfiguration of the toe nail. The natural progression is for a new nail to grow beginning at the base of the nail bed, where the matrix is located. Thus the old toe nail may remain attached to this segment while the new nail grows from below. You may keep a bandage over the nail to prevent it from tearing off by trauma.
While infection is not common, signs to be aware of include worsening pain, warmth, redness or drainage from the site. If you had a procedure done at the time of the hematoma, the risk of infection may be increased. In addition, peripheral vascular disease, poor circulation to the foot such as in diabetes, may delay healing and increase risk of infection. Infection requires antibiotics. It is reasonable and recommended to have the toe physically examined to determine if it is healing appropriately. Please speak with your physician.