Can be a small hematoma
Thanks for posting your query.
A small bruise
with a white knot can be a small hematoma due to some injury
in the area. The white center can be suggestive of a resolving hematoma. In case there is pain and swelling in the area then an infection needs to be ruled out. Otherwise there is no need to worry. This is likely to subside on its own.
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Dr. Praveen Tayal.
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