Damage to the nails due to accidents is a very common problem. Fortunately, it rarely requires medical treatment. The doctors who would be able to discuss this issue with you in greater detail include your
primary care doctor. When the nail and the tissue under it is damaged, say by dropping a heavy box, much of the damage is actually not to the nail but rather to the tissue under the nail. This is because the nail is actually dead, but the sensitive nail bed under it is alive. A 'bruised nail' is actually bruising of the tissue under the nail. Sometimes, if small blood vessels rupture, this can lead to leakage of blood into the space between the nail bed and the nail, leading to what is called a subungual hematoma. This looks like a purplish discoloration under the nail. Usually subungual hematomas do not need treatment. However, sometimes they cause pressure build-up, in which case a small hole can be made in the nail by your doctor to remove the pressure. As always, the diagnosis and the management of your specific concern may require a physical examination by your personal physician. If there is pain or other concerning symptoms, you may consider scheduling a visit with your primary care doctor.