What to know about a bruised big toenail

This is called a subungual haematoma. A small, comfortable bruise can often be protected while the nail grows, whereas strong throbbing pain, a major injury or an unstable nail needs professional assessment.

A direct blow can break tiny blood vessels under the hard nail plate. Repeated contact in tight shoes can do the same more gradually. The trapped blood may look red, purple, brown or black and should move outward as new nail grows from the base.

Not every dark nail is a bruise. Fungal change, pigment in the nail, a growth under the nail or another disorder can cause Nail Discoloration. A clinician should inspect colour that appeared without injury, forms a lengthwise band, changes shape or extends onto surrounding skin.

Rest from the activity that caused the injury, elevate the foot, and apply a cool pack wrapped in cloth for short periods. Choose open or roomy footwear that does not press on the nail. Keep any split skin clean and cover it with a light, non-stick dressing.

Do not burn, drill or pierce the nail at home; this can damage tissue and introduce infection. A trained clinician can decide whether relieving pressure is appropriate. If the nail loosens, do not pull it off. Trim only a free edge that catches, leaving attached portions in place.

Seek prompt care after a crushing injury, if pain is intense or worsening, the toe looks bent, walking is difficult, bleeding will not stop, or there is a deep cut. These findings can accompany a fracture or injury to the nail bed.

Redness spreading beyond the nail, increasing warmth, pus, fever or worsening swelling may indicate infection. Arrange assessment sooner if you have diabetes, poor circulation, reduced foot sensation or immune suppression. Unexplained or changing dark pigment also deserves a dermatology review.

Ask whether the toe needs imaging, whether pressure under the nail should be relieved, and how to dress any wound. If damage is extensive or recurrent, ask when Nail Surgery is considered and how footwear can prevent another episode.