Hello,
Thanks for posting your query.
You have provided with very small information regarding your problem. In order to guide you appropriately, I will need a few more details regarding your problem, so please answer the following questions in as much detail as possible.

Since when is the knot present ?

Is the knot smooth and rubbery or firm in consistency ? Are there any other such knots over your feet ?

Do you have any problem with walking? Any pain, infection in the foot ?

Any recent weight loss, fever ?

According to the history provided, it most probably is a plantar fibroma. These nodules may lay dormant for years only to rapidly increase in size in a very short period of time.
An MRI may be helpful to show the true extent of the fibroma and whether or not it is pressing on adjacent tissue.

If, however, there is pain conservative management is indicated. Conservative care involves orthopedic padding around the area via padding in the shoe to keep pressure off the area. Doing a hot fomentation might also help temporarily.

Kindly do respond to above queries.

I hope I have answered your query. I will be available to answer your follow up queries.

Please accept my answer in case you do not have further queries.
Wishing you good health.
Regards.
Dr. Praveen Tayal.

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