Hello, four wks ago i hit my head on the car trunk lid. no blood but a week later i noticed a bump which now still has a raised scab. action needed?

Contusion: This is most likely soft tissue bruising (contusion) or a collection of blood under the skin (hematoma). It is common to get these after a head injury. They should settle on their own over a few months. There is nothing to be concerned about.

TD: If you broke the skin make sure your tetanus vaccination is updated. Have the wound examined to make sure it is cleansed and irrigated free of infection and that your scalp and skull are not in need of treatment. Good luck.